Title of Invention	"ENGINE ASSITOR SERVING AS ENGINE STARTER"
Abstract	An engine assistor serving as an engine starter, including a motor (M) having a rotor connected to a crank shaft of an engine and a stator having multi-phase windings and which performs both engine starting and engine torque assist by said motor (M), comprising: a rotational angle detector for detecting a rotational angle of said crank shaft and generating an angle signal; a brushless type energization controller for electrically switching the connection between each stator coil of said motor (M) and a power supply line (L1) on the basis of the angle signal detected by said rotational angle detector; a brush type energization controller for receiving the rotational motion of said crank shaft and mechanically switching the contact between each stator coil and the power supply line (L1) by means of brushes in accordance with the rotational angle of said crank shaft; and an assist controller for biasing said brushless type energization controller to drive said motor (M); wherein said brush type energization controller holds the contact between each stator coil and the power supply line (L1) upon engine starting and releases the contact between each stator coil and the power supply line (L1) not upon engine starting.

Title of Invention

"ENGINE ASSITOR SERVING AS ENGINE STARTER"

Abstract

An engine assistor serving as an engine starter, including a motor (M) having a rotor connected to a crank shaft of an engine and a stator having multi-phase windings and which performs both engine starting and engine torque assist by said motor (M), comprising: a rotational angle detector for detecting a rotational angle of said crank shaft and generating an angle signal; a brushless type energization controller for electrically switching the connection between each stator coil of said motor (M) and a power supply line (L1) on the basis of the angle signal detected by said rotational angle detector; a brush type energization controller for receiving the rotational motion of said crank shaft and mechanically switching the contact between each stator coil and the power supply line (L1) by means of brushes in accordance with the rotational angle of said crank shaft; and an assist controller for biasing said brushless type energization controller to drive said motor (M); wherein said brush type energization controller holds the contact between each stator coil and the power supply line (L1) upon engine starting and releases the contact between each stator coil and the power supply line (L1) not upon engine starting.

Full Text	[0001] The present invention relates to an engine assisto serving as engine starter for performing engine starting and engine torque assist by means of a common motor, and particularly to an engine assistor serving as engine starter in which the motor substantially functions r' selectively as a brush motor or a brushless motor. [0002] —* [Prior Art] A vehicle improved from the viewpoint of environmental pollution measure and energy-saving has been disclosed, for example, in Japanese Patent Laid-open No. Hei 4-303030, which vehicle mounts an engine and a motor as drive sources and includes an engine assistor for compensating for an insufficient engine torque with the motor. [0003] ) [Problem to be Solved by the Invention] A torque assist motor does not require a large drive torque and receives a relatively small current, but it is driven for a relatively long period of time. A non-contact type brushless motor excellent in durability is used for such a torque assist motor. On the other hand, an engine starter is driven for a short period of time, but it requires a large drive torque. A brush motor suitable for control of a large current is used for such an engine starter. [0004] Accordingly, in the case where engine starting and engine torque assist are performed by a common motor, if a brushless motor is used as the common motor, the motor must be enlarged to obtain a sufficient drive torque upon starting of the engine. On the other hand, if a brush motor is used as the common motor, such a brush motor is effective to obtain a sufficient torque without increasing the size of the motor; however, since brushes are usually slid during running of the vehicle, the brush portion is significantly deteriorated. [0005] An object of the present invention is to solve the above problem of the prior art, and to provide an engine assistor serving as engine starter including a generator/motor which functions as a brush motor upon starting of the engine and which functions as a brushless motor upon torque assist other than upon starting of the engine, and upon power generation. [Means for Solving the Problem] According to the present invention there is provided an engine assistor serving as an engine starter, including a motor (M) having a rotor connected to a crank shaft of an engine and a stator having multi-phase windings and which performs both engine starting and engine torque assist by said motor (M a rotational angle detector for detecting a rotational angle of said crank shaft and generating an angle signal; a brushless type energization controller for electrically switching the connection between each stator coil of said motor (M) and a power supply line (LI) on the basis of the angle signal detected by said rotational angle detector; a brush type energization controller for receiving the rotational motion of said crank shaft and mechanically switching the contact between each stator coil and the power supply line (L1) by means of brushes in accordance with the rotational angle of said crank shaft; and an assist controller for biasing said brushless type energization controller to drive said motor (M); wherein said brush type energization controller holds the contact between each stator coil and the power supply line (L1) upon engine starting and releases the contact between each stator coil and the power supply line (L1) not upon engine starting. With this configuration, since the selection/switching of a stator coil to be excited is performed by the brush mechanism at a timing for controlling a relatively large exciting current, for example, upon starting of the engine, it is not required to increase the capacity of each switching means constituting the brushless type energization control means. On the other hand, the selection/switching of a stator coil to be excited is preformed by the brushless type energization control means at a timing in which the engine is rotated at a rotational speed equal to or more than a specific value, for example upon engine assist, that is, the brush mechanism can be kept in the non-contact state, it is possible to prevent occurrence of wear and deterioration of brushes. [Brief Description of the Drawings] [Fig. 1] A side view of the entire configuration of a scooter-type motorcycle mounted with an engine stopping/starting control system of the present invention. [Fig. 2] A plan view of an instrument and its neighborhood of the scooter-type motorcycle. [Figs. 3a and 3b] Views typically showing the structure of a hinge portion of the front portion of a seat. [Figs. 4a and 4b] Sectional views showing a main portion of a throttle grip. [Fig. 5] A sectional view, taken on line II-II of Fig. 1, showing an internal combustion engine. ,• [Fig. 6] A block diagram showing the entire configuration of one example of a starting/stopping control system. [Fig. 7] A block diagram showing the function of a main control unit. [Fig. 8] A diagram showing main operations of the main control unit. [Fig. 9] A block diagram showing the entire configuration of another example of a starting/stopping control system. [Fig. 10] A block diagram showing the configuration of an essential portion of a generator/motor functioning as an engine assistor serving as engine starter according to one embodiment of the present invention. [Fig. 11] A block diagram showing one example in which the engine assistor serving as engine starter is applied to a •single-phase/six-pole motor. [Fig. 12] A block diagram showing one example in which the engine assistor serving as engine starter is applied to a three-phase motor. [Figs. 13a to 13c] Diagrams showing one example of an assist control method. [Figs. 14a to 14c] Diagrams showing another example of the assist control method. [Fig. 15] A diagram showing an assist amount by the s~ generator/motor as functions of a throttle opening and a rotational number of the engine. [0008] [Embodiments of the Invention] Hereinafter, the present invention will be described in detail with reference to the drawings. Fig. 1 is a general side view of a scooter-type motorcycle 1 mounted with an engine stopping/starting control system according to one embodiment of the present invention. [0009] A body front 2 is connected to a body rear 3 via a low level floor 4. A body frame constituting a skeleton of a vehicular body is basically composed of a down tube 6 and a main pipe 7. A fuel tank and a containing box (both not shown) are supported by the main pipe 7, and a seat 8 is arranged over the fuel tank and containing box. [0010] At the body front 2, a handle bar 11 is rotatably supported by a steering head 5 in such a manner as to extend upward therefrom and a front fork 12 is rotatably supported by the steering head 5 in such a manner as to extend downward therefrom. A front wheel 13 is rotatably supported by the lower ends of the front fork 13. The upper portion of the handlebar 11 is covered with a handle cover 33 serving as an instrument board. A bracket 15 is projectingly provided on the lower end of a rising portion of the main pipe 7, and a swing unit 17 is swingably connected to and supported by the bracket 15 via a link member 16. [0011] A single-cylinder/two-stroke internal combustion engine 200 is mounted on the front portion of the swing unit 17. A belt type continuously variable transmission 35 provided extending rearward from the engine 200, a reduction mechanism 38 is provided on the rear portion of the transmission 35 via a centrifugal clutch. A rear wheel 21 is rotatably supported by the reduction mechanism 38. A rear cushion 22 is interposed between the upper end of the reduction mechanism 38 and the upper bend portion of the main pipe 7. A carburetor 24 connected to an intake pipe 23 extending from the upper portion of a cylinder head of the engine 200 and an air cleaner 25 connected to the carburetor 24 are arranged over the swing unit 17. [0012] A main stand 26 is pivotably mounted on a hanger bracket 18 projectingly provided on the lower portion of a unit swing case 31. The base end of a kick arm 28 is fixed to a kick shaft 27 projecting from a transmission case cover 36 of the belt type continuously variable transmission 35. A kick pedal 29 is provided at the leading end of the kick arm 28. [0013] Fig. 2 is a plan view of an instrument panel and its neighborhood of the motorcycle 1. A speed meter 91, a stand-by indicator 56, and a battery indicator 76 are provided in an instrument panel 90 mounted to the handle cover 33. As will be described in detail later, the stand-by indicator 56 flashes when the engine is stopped during control of stopping/starting of the engine for warning the driver of the fact that the present state is a state in which the engine will be started to move the vehicle directly after a throttle is opened. The battery indicator 76 is turned on if a battery voltage is lowered for warning the driver of the lack of charged power of the battery. [0014] The handle cover 33 is also provided with an idle switch 53 for permitting or restricting idling and a starter switch 58 for starting a starter motor. A throttle grip 92 and a brake lever 93 are provided at the right end portion of the handlebar 11. It should be noted that while a horn switch, a winker switch and the like are provided on the roots of the right and left throttle grips like the related art motorcycle, they are not shown in Fig. 2 . [0015] Figs. 3a and 3b typically show the structure of a hinge portion provided at the front of the seat 8, which hinge portion is designated by a round mark depicted by the broken line in Fig. 1. In this embodiment, a hinge member 81, which is fixed on the front of the back face of the seat 8, has an opening 82 elongated in the vertical direction. A hinge shaft 85 fixed on the vehicular body side passes through the elongated opening 82, so that the seat 8 is supported swingably around the hinge shaft 85 and movably in the vertical direction. A coil spring 83 for elastically biasing a pressing piece 83a and a sitting switch 54 are provided on the vehicular body side opposed to the back face of the hinge member 81. [0016] With this configuration, in the non-sitting state in which a driver is not sit in the seat 8, as shown in Fig. 3a, since the seat 8 is pushed up by the coil spring 83 until the hinge shaft 85 is brought in contact with the lower end of the elongated opening 82, the sitting switch 54 is turned into the OFF state. [0017] On the contrary, in the sitting state in which the driver is sit in the seat 8, as shown in Fig. 3b, since the seat 8 is pushed down against the elastic force of the coil spring 83, the sitting switch 54 is turned into the ON state. Accordingly, it can be confirmed whether or not the driver is sitting in the seat 8 by keeping watch on the ON/OFF state of the sitting switch 54. Also, in this embodiment, since the sitting switch 54 is provided on the front side of the seat 8, even if the driver is short in stature, it can be certainly detected whether or not he is sit in the seat 8. [0018] Fig. 4a is a sectional view showing a main portion of the throttle grip 92, and Fig. 4b is a sectional view taken on line I-I of Fig. 4a. As shown in Fig. 4a, a throttle grip main body 182 is turnably inserted around a handle pipe 181 and is covered with a grip cover 183. The throttle grip main body 182 has a flange 182a which projects from the circumference of the throttle grip main body 182. As shown in Fig. 4b, one end 185a of a throttle wire 185 is locked to the flange 182a. The throttle grip main body 182 is usually biased on the accelerator closing side by the elastic force of a spring 184. When the throttle grip main body 182 is twisted in the opening direction against the elastic force of the spring 184, the throttle wire 185 is twisted inward to open the throttle. [0019] In this embodiment, the throttle grip 92 has a throttle switch 52 which closes (or opens) a contact when the throttle grip is full closed and which opens (or closes) the contact when the throttle grip is opened by a predetermined angle. In other words, the throttle switch 52 opens (or closes) the contact in an angle range less than a play angle 9 , that is, before the' throttle actually begins to be opened. This allows the throttle switch 52 to be turned on without opening the throttle. Accordingly, the engine can be operated by the intention of the driver even in the stopping state of the vehicle. [0020] The throttle grip main body 182 is additionally applied with the elastic force of a throttle spring (not shown) when the opening angle of throttle grip main body 182 reaches an angle (> 0 ) at which the throttle actually begins to be opened, and accordingly, the opening/closing operation of the throttle switch 52 only in the angle range less than the play angle can be easily performed. [0021] Fig. 5 is a sectional view, taken on line II-II of Fig. 1, showing the engine 200. The engine 200 includes a crank case 202 divided into right and left crank cases 202R and 202L for rotatably supporting a crank shaft 201 extending from right to left in the horizontal direction, and a cylinder block 203 and a cylinder head 204 which are sequentially stacked on the crank case 202. The cylinder block 203 has an exhaust passage (not shown), and it also has scavenging passages 205 each having a scavenging port opened in a cylinder bore of the cylinder block 203 so that the cylinder block 203 is communicated to a crank chamber of the crank case 202. [0022] An ignition plug 206 is fitted in the cylinder head 204 in such a manner as to be directed toward a combustion chamber. The cylinder head 204 and the cylinder block 203 are covered with a fan shroud 207 except for the exposed portion of the ignition plug 206. The left crank case 202L serves as a belt-type continuously variable transmission chamber case. A belt drive pulley 210 is rotatably provided around the crank shaft 201 passing through the left crank case 202L. [0023] The belt drive pulley 210 has a fixed side pulley half 210L and a movable side pulley half 210R. The fixed side pulley half 210L is fixed to the left end portion of the crank shaft 201 via a boss 211. The movable side pulley half 210R, positioned on the right side of the fixed side pulley half 210L, is spline-fitted to the crank shaft 201 to be movable close to or apart from the fixed side pulley half 210L. A V-belt 212 is wound between both the pulley halves 210L and 210R. [0024] A cam plate 215, positioned on the. right side of the movable side pulley half 210R, is fixed to the crank shaft 201. A slide piece 215a provided at the outer peripheral end of the cam plate 215 is slidably engaged with a cam plate slide boss 210Ra which is axially formed at the outer peripheral end of the movable side pulley half 210R. The side surface, on the cam plate 215 side, of the movable side pulley half 210R is tapered toward the cam plate 215 side, and dry weight rollers 216 are contained in a state being held between the inner surface of the taper portion of the movable side pulley half 210R and the cam plate 215. [0025] As the rotational speed of the crank shaft 201 is increased, the dry weight rollers 216, which are held between the movable side pulley half 210R and the cam plate 215 and are rotated therewith, are moved in the centrifugal direction by the centrifugal force applied thereto. As a result, the movable side pulley half 210R is pushed by the dry weight rollers 216 to be moved leftward, that is, close to the fixed side pulley half 210L, so that the V-belt 212 held between both the pulley halves 210L and 210R is moved in the centrifugal direction. This increases the winding radius of the V-belt 212. The V-belt 212 is wound around' the belt drive pulley 210 and also around a belt driven pulley (not shown) provided on the rear side, so that a power is automatically adjusted and is transmitted to the reduction mechanism provided on the rear side via a centrifugal clutch, to thus drive a rear wheel. [0026] A transmission case cover 220, which extends rearward from the belt drive pulley 210 located on the front side, covers from left the belt-type continuously variable transmission chamber. The kick shaft 27 turnably passes through and is supported by the front portion of the transmission case cover 220. A drive helical gear 222 is fitted to the inner end portion of the kick shaft 27 and is biased by a return spring 223. A slide shaft 224 coaxial with the crank shaft 201 is rotatably, axially and slidably supported by the inner surface of the front portion of the transmission case cover 220. A driven helical gear 225 is formed around the slide shaft 224 and meshed with the drive helical gear 222. A ratchet wheel 226 is fixed at the right end of the driven helical gear 225. The ratchet wheel 226, drive helical gear 222, and driven helical gear 225 are biased leftward by a friction spring 227. [0027] A ratchet facing to the ratchet wheel 226 is formed on the boss 211 on the crank shaft 201 side. Both the ratchet and ratchet wheel 226 can be moved close to or apart from each other by sliding motion of the slide shaft 224. When the kick pedal 29 is actuated and the kick shaft 27 is rotated against the return spring 223, the drive helical gear 222 integrated with the kick shaft 27 is rotated, and the driven helical gear 225 meshed with the drive helical gear 222 is slid rightward against the biasing force of the friction spring 227 while being rotated together with the slide shaft 224, so that the ratchet wheel 226 is meshed with the ratchet of the boss 211 to forcibly rotate the crank shaft 201, thus starting the internal combustion engine 200. [0028] The right crank case 202R, formed into an approximately cylindrical shape, extends rightward from a main bearing 209 for rotatably supporting the crank shaft 201. The crank shaft 201 projects along the center axis of the right crank case 202R. An assistor/starter/generator 250 (hereinafter, sometimes referred to simply as "generator/motor") having a combination of a function as an assist motor, a function as a starter motor, and a function of an AC generator (ACG) is disposed in the cylinder of the right crank case 202R. [0029] An inner rotor (rotational inner magnetic type rotor) 251 is fitted around a taper portion formed at the leading end of the crank shaft 201 and is fixed thereto with a nut 253. The inner rotor 251 is thus rotated together with the crank shaft 201. Six grooves, each being formed in an arcuate shape in cross - section, are formed in the outer peripheral surface portion of the inner rotor 251. A magnet 271 made from a neodymium-iron-boron alloy is fitted in each of the six grooves. [0030] An outer stator 270 is arranged around the outer periphery of the inner rotor 251 in such a manner that the outer peripheral edge thereof is fastened to and supported by a cylindrical wall 202a of the crank case 202 with a bolt 279. A stator core of the outer stator 270 is composed of steel sheets laminated to each other, and a power generating coil 272 and a starting coil 273 as stator coils are wound around a plurality of teeth extending toward the center from the annular portion of the outer periphery of the stator core. The generating coil 272 and starting coil 273 are wound' around the teeth in such a manner as to be offset on the inner side in the direction toward the crank shaft. In other words, the amounts, projecting outward in the axial direction of the crank shaft 201, of the coils 272 and 273 are made small. [0031] The power generating coil 272 and the starting coil 273, which project inward rather than outward in the axial direction within the cylindrical wall 202a of the crank case 202, form an annular inner space in which a rectifying brush mechanism 263 is provided. A brush holder 262, through which the crank shaft 201 passes in the inner space, is fitted to the crank shaft 201 in such a manner as not to be permitted in its relative rotation in the circumferential direction and to be permitted only in its sliding motion in the axial direction. A spring 274 is interposed between the brush holder 262 and the inner rotor 251 for biasing the brush holder 262 inward in the axial direction. [0032] A plurality of brushes 261 are provided at specific positions on the inner surface of the brush holder 262 in such a manner as to project therefrom by the elastic forces of springs. A commutator holder 265 facing to the inner surface of the brush holder 262 is, provided in such a manner that its center is penetrated by the crank shaft 201 and its outer peripheral edge is fixedly supported by portions, largely projecting inward in the axial direction, of the power generating coil 272 and the starting coil 273. [0033] Commutator pieces 267 are concentrically arranged at specific positions on the surface, facing to the brush holder 262, of the commutator holder 265. The brush holder 262, which is rotated together with the crank shaft 201, is moved close to or apart from the fixed commutator holder 265. When the brush holder 262 is moved close to the commutator holder 265, each brush 261 is brought in contact with the corresponding commutator piece 267. [0034] The outer portion, in the axial direction of the crank shaft 201, of the inner rotor 251 has an inner cylindrical portion 231 covering the surroundings of the nut 253 screwed in the leading end of the crank shaft 201 and an outer cylindrical portion 232 concentrically covering the inner cylindrical portion 231. Both the cylindrical portions 231 and 232 extend axially outward, to constitute a governor mechanism 230. r-To be more specific, the inner peripheral surface of the outer cylindrical portion 232 is tapered to constitute a governor outer; a governor inner 233 is axially slidably fitted around the outer periphery of the inner cylindrical portion 231; and balls 234 as a governor weight are interposed between the governor inner 233 and the outer cylindrical portion 232. [0035] A connecting shaft, 235 with its one end fixed to the axially movable governor inner 233 of the governor mechanism 230 passes through the inner rotor 251 in parallel to the crank shaft 201, and the leading end of the connecting shaft 235 is fitted to the brush holder 262. In this way, the connecting shaft 235 connecting the governor inner 233 to the brush holder 262 allows both the governor inner 233 and the brush holder 262 to be moved together with each other in the axial direction of the crank shaft 201. [0036] When the crank shaft 201 is stopped, the brush holder 262 is moved inward in the axial direction by the biasing force of the spring 223 to bring the brushes 261 in contact with the commutator pieces 267. In this state, if a current is supplied from the battery, it flows to the starting coil 273 by way of the contact between the Drushes 261 and the commutator pieces 267, to generate a rotational torque applied to the inner rotor 251. The rotation of the inner rotor 251 rotates the crank shaft 201, thereby starting the engine 200. That is to say, the generator/motor 250 functions as a brush motor with the starting coil 273 taken as the stator coil. [0037] As the rotational number of the engine is increased, the balls 234 are moved, by the centrifugal force, in the outer peripheral direction on the inner tapered surface of the outer cylindrical portion 232, so that the governor inner 233 is slid outward in the axial direction. At this time, the brush holder 262 integrated with the connecting shaft 235 is moved outward in the axial direction, and when the rotational number of the engine exceeds a specific value, the brushes 261 are automatically separated from the commutator pieces 267. After that, the charging to the battery is performed by the power generating coil 272. That is to say, the generator/motor 250 functions as a brushless motor with the starting coil 273 taken as the stator coil. [0038] An annular disk-like rotor 240 for" detecting a crank angle is provided on the outer cylindrical portion 232 constituting the main part of the governor mechanism 230 in such a manner that its inner peripheral edge is integrally fitted to the edge portion of the outer cylindrical portion 232. An angle sensor 49 is arranged at a specific position in the vicinity of the outer peripheral edge of the rotor 240. The angle sensor 49 detects serrations formed on the outer peripheral edge of the rotor 240 rotated integrally with the crank shaft 201 via the inner rotor 251, to determine the crank angle. The annular disk-like rotor 240 covers from outside the power generating coil 272 and the starting coil 273 of the outer stator 270. A fan member 280 for forcibly air-cooling the internal combustion engine is integrally provided on the outer side of the rotor 240 in the axial direction. [0039] The base of a central cone portion 280a of the fan member 280 is fixed on the outer cylindrical portion 232 of the inner rotor 251 with a bolt 246. A fan 280b provided on the outer periphery of the central cone portion 280a is erected outside the rotor 240. The fan member 280 is covered with a fan cover 281. [0040] According to the generator/motor for a vehicle in this embodiment, as described above, the rectifying brush mechanism 261 is disposed inward from the inner rotor 251 in the axial direction and the governor mechanism 230 separated from the rectifying brush mechanism 261 is disposed outward from the inner rotor 251 in the axial direction. Accordingly, the amount, protruded outward in the axial direction of the crank shaft, of the generator/starter can be suppressed. [0041] Further, since the power generating coil 272 and the starting coil 273 are wound around the yokes of the stator core of the outer stator 270 in such a manner as to be offset inward in the axial direction, that is, to make small the amounts, projecting outward in the axial direction, of the coils 272 and 273, the rotor 240 and the fan member 280 can be located relatively inward in the axial direction to thereby further make small the amount, projecting outward in the axial direction, of the generator/starter. [0042] Outside air introduced from an outside air suction port 281a of the fan cover 281 by rotation of the fan 280b is spread toward the outer periphery along the central cone portion 280a; however, since the rotor 240 cuts off the introduced air and prevents permeation of the outside air to the generator/motor 250 side, the outside air less permeates to the rectifying brush mechanism 261 located at the back of (axially inward from) the generator/motor 250. This prevents the rectifying brush mechanism 261 from being affected by dust contained in the outside air. [0043] Fig. 6 is a block diagram showing the entire configuration of a starting/stopping control system in the engine 200 including the generator/motor 250 for directly rotating the crank shaft 201 as described above. In this figure, the same symbols as those described above designate the same or similar parts. [0044] The engine stopping/starting system in this embodiment includes an operational mode in which idling is restricted and an operational mode in which idling is permitted. To be more specific, the system includes an "engine-stopping/vehicle-moving mode (idling restricting mode)" in which when the vehicle is stopped, the engine is automatically stopped, and when the throttle grip is actuated in the stopping state of the engine, the engine is automatically re-started to move the vehicle, and the system also includes an "engine-starting mode (idling permitting mode)" in which idling is permitted for warming-up upon starting of the engine. [0045] The generator/motor 250 is coaxially connected to the crank shaft 201 of the engine 200. The generator/motor 250 is composed of an assist motor 70, a starter motor 71 and an AC generator (ACG) 72. A power generated by the AC generator 72 is charged in a battery 68 via a regulator/rectifier 67. When a starter relay 62 is made conductive, the battery 68 supplies a drive current to the starter motor 71 and also supplies load currents to various electrical equipment 74 and a main control unit 60 via a main switch 73. [0046] To the main control unit 60 is connected an angle sensor 49 for detecting a rotational angle of the engine, a throttle sensor 50 for detecting the opening of the throttle, an Ne sensor 51 for detecting the rotational number Ne of the engine, the throttle switch 52 which closes the contact when the throttle opening exceeds a predetermined value, an idle switch 53 for permitting or restricting idling of the engine 200, the sitting switch 54 which closes the contact when a driver sits in the driver's seat, a vehicular speed sensor 55 for detecting a vehicular speed, the stand-by indicator 56 which flashes upon stopping of the vehicle in the engine-stopping/vehicle-moving mode to be described later, a headlamp switch 57 for turning on/off the headlamp 69, the starter switch 58 for driving the starter motor 71 of the generator/motor 250 to start the engine 200, a stop switch 59 which closes the contact in response to a braking operation, and the battery indicator 76 which is turned on when the voltage of the battery 68 is equal to or less than a predetermined value (for example, 10 V) for warning the driver of the lack of charging power in the battery. [0047] To the main control unit 60 are also connected an ignition control device (including an ignition coil) 61 for igniting the ignition plug 206, a control terminal of the starter relay 62 for supplying a power to the starter motor 71, a control terminal of a headlamp relay 63 for supplying a power to the headlamp 69, a control terminal of a by-starter relay 64 for supplying a power to the by-starter 65 mounted to the carburetor 66, and a buzzer 75 for generating an alarm for giving caution to the driver before the driver goes away from the vehicle without turning off the main switch 73 or the headlamp 69 is automatically turned off. [0048] Fig. 7 is a block diagram for concretely showing the configuration of the main control unit 60, in which the same symbols as those described above designate the same or similar parts. Fig. 8 is a diagram showing main operations of the main control unit 60. [0049] An operational mode switching unit 300 switches, the operational mode of the engine stopping/starting control system of the present invention into either the "engine-starting mode" in which idling is permitted or the "engine - stopping/vehicle-moving mode" in which idling is restricted, in accordance with the ON/OFF state of the idle switch 53 and the state of the vehicle. [0050] In the operational mode switching unit 300, a signal indicating the ON/OFF state of the idle switch 53 is inputted in both an operational mode signal outputting unit 301 and an inverter 302. The signal indicating the ON/OFF state of the idle switch 53 indicates an "L" level in the OFF state (restriction of idling) 'of the idle switch 53 and an "H" level in the ON state (permission of idling) of the idle switch 53. The inverter 302 reversely outputs the signal indicating the ON/OFF state of the idle switch 53. [0051] A vehicular speed continuation discriminating unit 303, which includes a timer 303a, outputs a signal of "H" level when a vehicular speed equal to or more than a predetermined value is detected for a predetermined time or more. An AND circuit 304 outputs a logical product of the output signal from the discriminating unit 303 and the output signal from the inverter 302 to the operational mode signal outputting unit 301. [0052] When the main switch 73 is turned on, the operational mode signal outputting unit 301 starts the "engine-starting mode" in which idling is permitted. If upon the "engine-starting mode", the output signal from the AND circuit 304 indicates the "H" level, that is, the idle switch 53 is turned off and the vehicular speed equal to or more than the predetermined value is detected for the predetermined time or more, the operational mode is shifted from the "engine-starting mode" to the "engine-stopping/vehicle-moving mode" in r-which idling is restricted. Also, if upon the "engine-stopping/vehicle-moving mode", the idle switch 53 is turned on again, the operational mode is shifted from the "engine-stopping/vehicle-moving mode" to the "engine-starting mode" . An operational mode signal S301 outputted from the operational mode signal outputting unit 301 indicates the "L" level during the "engine-starting mode" and the "H" level during the "engine-stopping/vehicle-moving mode". [0053] A starter relay control unit 400 allows manual or automatic starting of the starter relay 62 under a specific condition in accordance with the operational mode. In the starter relay control unit 400, a detection signal outputted from the Ne sensor 51 is supplied to an idling-or-less discriminating unit 401. When the rotational number of the engine is equal to or less than a specific idling rotational number (for example, 800 rpm) , the discriminating unit 401 outputs a signal of "H" level. An AND circuit 402 outputs a logical product of the output signal from the discriminating unit 401, the signal indicating the ON/OFF state of the stop switch 59, and the signal indicating the ON/OFF state of the starter switch 58. An AND circuit 403 outputs a logical product of the output signal from the AND circuit 402 and the reversal signal of the operational mode signal S301. [0054] An AND circuit 404 outputs a logical product of the output signal from the idling-or-less discriminating unit 401, the signal indicating the ON/OFF state of the throttle switch 52, and the signal indicating the ON/OFF state of the sitting switch 54. An AND circuit 405 outputs a logical product of the output signal from the AND circuit 404 and the operational mode signal S301. An OR circuit 406 outputs a logical sum of the output signals from the AND circuits 403 and 405 to the starter relay 62. [0055] With this configuration, since the operational mode signal S301 indicates the "L" level during the "engine-starting mode", the AND circuit 403 is turned into an enable state. Accordingly, if the starter switch 58 is turned on by the driver when the rotational number of the engine is equal to or less than the idling rotational number and the stop switch 59 is turned on (during braking operation), the starter relay 62 is made conductive to thereby start the starter motor 71. [0056] On the contrary, the AND circuit 4'05 is turned into an enable state during the "engine-stopping/vehicle-moving mode". Accordingly, if the rotational number of the engine is equal to or less than the idling rotational number and the sitting switch 54 is turned on (during sitting of the driver in the driver's seat) to open the throttle, the starter relay 62 is made conductive to start the starter motor 71. [0057] In a by-starter control unit 500, the output signal from the Ne sensor 51 is inputted in an Ne discriminating unit 501. The Ne discriminating unit 501 outputs a signal of "H". level if the rotational number of the engine is equal to or more than a predetermined value, to close the by-starter relay 64. With this configuration, even in either of the above operational modes, it is possible to make rich the fuel when the rotational number of the engine is equal to or more than the predetermined value. [0058] In an indicator control unit 600, the output signal from the Ne sensor 51 is inputted in an Ne discriminating unit 601. The Ne discriminating unit 601 outputs a signal of "H" level if the rotational number of the engine is equal to or less than a predetermined value. An AND circuit 602 outputs a logical product of,-the signal indicating the ON/OFF state of the sitting switch 54 and the output signal from the Ne discriminating unit 601. An AND circuit 603 outputs a logical product of the output signal from the AND circuit 602 and the operational mode signal S301 to the stand-by indicator 56. The stand-by indicator 56 is turned off if the input signal indicates the "L" level, and flashes if the input signal indicates the "H" level. [0059] To be more specific, the stand-by indicator 56 flashes upon stopping of the vehicle during the "engine-stopping/vehicle-moving mode", and accordingly, if the stand-by indicator 56 flashes, the driver can recognize that he is able to immediately move vehicle by actuating the accelerator even if the engine is stopped. [0060] An ignition control unit 700 permits or prohibits the ignition operation performed by the ignition control device 61 under a specific condition in accordance with each operational mode. In the ignition control unit 700, a detection signal outputted from the vehicular speed sensor 55 is inputted in a running discriminating unit 701. The running discriminating unit 701 outputs a signal of "H" level if it discriminates that the vehicle is in the running state on the basis of the detection signal. An OR circuit 702 outputs a logical sum of the output signal from the running discriminating unit 701 and the signal indicating the ON/OFF state of the throttle switch 52. An OR circuit 703 outputs a logical sum of the output signal from the OR circuit 702 and the reversal signal of the operational mode signal S301 to the ignition control device 61. The ignition control device 61 executes, if the input signal indicates the "H" level, the igniting operation for each specific timing, and it interrupts the igniting operation if the input signal indicates the "L" level. [0061] With this configuration, since the reversal signal of the operational mode signal S301 indicates the "H" level in the "engine-starting mode", the OR circuit 703 usually outputs a signal of "H" level. Accordingly, the ignition control device 61 usually executes the igniting operation in the "engine-starting mode". On the contrary, in the "engine-stopping/vehicle-moving mode", the igniting operation is executed under such a condition that the vehicle is on running or the throttle is opened, while the igniting operation is prohibited if the vehicle is in the stopping state and the throttle is closed. [0062] A headlamp/buzzer control unit 800 automatically turns on/off the headlamp on the basis of the running state -of the vehicle or the driver sitting state in accordance with each operational mode, and generates as a buzzer sound an alarm for giving caution to the driver. [0063] A non-sitting continuation discriminating unit 801 receives the signal indicating the ON/OFF state of the sitting switch 54. The non-sitting continuation discriminating unit 801 includes two timers 8011 and 8012 for counting a driver non-sitting time. When the timers 8011 and 8012 each count a specific time-out period, the non-sitting continuation discriminating unit 801 outputs a signal S9011 or S8012 of "H" level. In this embodiment, the time-out period set in the timer 8011 is 3 sec, and the time-out period set in the timer 8012 is 1 sec. [0064] A non-ignition continuation discriminating unit 802 includes two timers 8021 and 8022 for counting a non-ignition time. In the non-ignition state, the discriminating unit 802 immediately outputs a signal S8023 of "H" level. When the timers 8021 and 8022 each count a specific time-out period, the discriminating unit 802 outputs a signal S8021 or S8022 of "H" level. In this embodiment, the time-out period set in the timer 8021 is 3.5 min, and the time-out period set in the timer 8022 is 3 min. [0065] An AND circuit 812 outputs a logical product of the output signal S8011 from the non-sitting continuation discriminating unit 801 and the output signal S8023 from the non-ignition continuation discriminating unit 802. An OR circuit 804 outputs a logical sum of the output signal S8021 from the non-ignition continuation discriminating unit 802 and the output signal from the AND circuit 812. An AND circuit 805 outputs a logical product of the output signal from the OR circuit 804 and the operational mode signal S301 to a reset terminal R of a flip-flop 810. [0066] An AND circuit 807 outputs a logical product of the signal indicating the ON/OFF state of the throttle switch 52 and the operational mode signal S301. An Ne discriminating unit 806 receives the output signal from the Ne sensor 51, and outputs a signal of "H" level if the rotational number of the engine is equal to or less than a predetermined value. An AND circuit 808 outputs a logical product of the output signal from the Ne discriminating unit 806 and the reversal signal of the operational mode signal S301. An OR circuit 809 outputs a logical sum of the output signals form the AND circuits 807 and 808 to a set terminal S of the flip-flop 810. An AND circuit 811 outputs a logical product of the output signal from a terminal Q of the flip-flop 810 and the signal indicating the ON/OFF state of the headlamp switch 57 to the headlamp relay 63. The headlamp relay 63 turns on the, headlamp 69 if it receives a signal of "H" level, and turns off the headlamp 69 if it receives a signal of "L" level. [0067] With this configuration, in the "engine-starting mode", since the reversal signal of the operational mode signal S301 indicates the "H" level, the AND circuit 808 is turned into the enable state. Accordingly, if the rotational number of the engine is equal to or more than the predetermined value, the flip-flop 810 is set, so that the headlamp is turned on if the headlamp switch 57 is turned on. [0068] In the "engine-stopping/vehicle moving mode", since the operational mode signal S301 indicates the "H" level, each of the AND circuits 805 and 807 is turned into the enable state. Accordingly, if the output signal from the OR circuit 804 indicates the "H" level, the flip-flop 810 is reset, to automatically turn off the headlamp. [0069] That is to say, the headlamp in the "engine-stopping/vehicle-moving mode" is turned off if the non-ignition state is continued for a time-out period (3.5 min in this embodiment) of the timer 8021 or more so that the output signal S8021 indicates the "H" level, or if the non-sitting state in the non-ignition state is continued for a time-out period (3 sec in this embodiment) of the timer 8011 or more so that the output signal from the AND circuit 812 indicates the "H" level. [0070] As a result of examination by the present inventors, it is revealed that a vehicle stopping time for waiting for a signal light (blue) or a chance for right-turning in an intersection is substantially in a range of 30 sec to 2 min. Accordingly, a vehicle stopping state after an elapse of the above vehicle stopping time ranging from 30 sec to 2 min is highly estimated as a vehicle stopping state other than that for waiting for a signal light (blue) or a chance for right-turning, that is, as a vehicle stopping state in which the headlamp is not required to be left turned on. As a result, just as in this embodiment, by allowing the headlamp to be left turned on until the non-ignition state is continued for more than a predetermined time (for example, 3.5 min), it is possible to leave the headlamp turned on in the vehicle stopping state for waiting for a signal light (blue) or a chance for right-turning, and also to suppress the wasteful power consumption of the battery because the headlamp is automatically turned off when the vehicle stopping time exceeds 3.5 min. [0071] The state in which the driver non-sitting state is detected after stopping of the vehicle is also highly estimated as a vehicle stopping state other than that for waiting for a signal light (blue) or a chance for right-turning. On the basis of the experience, however, it is highly estimated that a driver temporarily stands up while straddling the vehicle directly after stoppage of the vehicle at an intersection, and therefore, it may be undesirable to automatically turn off the headlamp simultaneously with detection of the driver non-sitting state. For this reason, in this embodiment, the control system is configured such that the non-sitting time in the non-ignition state is counted, and the headlamp is automatically turned off if the above non-sitting time exceeds a predetermined time (3 sec in this embodiment) estimated as an elapsed time after a driver goes apart from the vehicle. [0072] In addition, when the throttle is opened in the vehicle-stopping state in the "engine - stopping/vehicle-moving mode", the output from the AND circuit 807 indicates the "H" level and the flip-flop 810 is set, and consequently the headlamp is automatically turned on. [0073] An AND circuit 813 of the headlamp control unit 800 outputs, to a buzzer drive unit 814, a logical product of the output signal S8012 from a non-sitting continuation discriminating unit 801, the output signal S9023 from a non-ignition continuation discriminating unit 802, and the operational mode signal S301. The AND circuit 815 outputs, to the buzzer drive unit 814, a logical product of the output signal S8022 from the non-ignition continuation discriminating unit 802, the operational mode signal S301, and the signal indicating the state of the headlamp switch 57. [0074] When the output signal from the AND circuit 813 indicates the "H" level, that is, when the non-sitting in the non-ignition state in the "engine - stopping/vehicle-moving mode" is continued for a time-out period (1 sec in this embodiment) of a timer 8012 or more, the buzzer drive unit 814 outputs a buzzer drive signal for repeatedly generating alarm sound at a cycle of ON-time (0.2 sec)/OFF-time (1.5 sec). At this time, the output of the buzzer drive signal is continued until the main switch 73 is turned off or the driver rides again on the vehicle. [0075] When the output signal from the AND circuit 815 indicates the "H" level, that is, the headlamp switch 57 is in the ON state in the "engine-stopping/vehicle-moving mode" and also the non-ignition state is continued for a time-out period (3 min in this embodiment) of the timer 8022, the buzzer drive unit 814 outputs the same buzzer drive signal until the timer 8141 counts a predetermined time-out period. With this configuration, the operation for stopping the buzzer becomes unnecessary. [0076] In this embodiment, if the non-sitting state continued for 1 sec or more with the main switch left turned on is detected when the engine is automatically stopped, it is discriminated that the driver goes away from the vehicle without turn-off of the main switch, with a result that the buzzer 75 is actuated. Accordingly, the driver can recognize the fact that the main switch is left turned-on. [0077] In this embodiment, the buzzer 75 is actuated before the headlamp automatic turn-off condition upon vehicle stopping state (the non-ignition state is continued for 3.5 sec or more) is established, for example, after the non-ignition state is continued for 3 min or more, so that the driver can previously recognize the automatic turn-off of the headlamp. That is to say, it is possible to prevent the headlamp from being automatically turned off without recognition of the driver. [0078] In the above embodiment, the configuration has been described that when it is detected that the non-sitting state is continued for 1 sec or more with the main power source left turned on after the engine is automatically stopped, the buzzer is continuously actuated until the main switch 73 is turned off or the driver rides again on the vehicle; however, in the case where it is supposed that the driver goes away from the vehicle without cut¬off of the main switch 73, for example, in the case where the vehicle is used for delivery service or bill collection service, the buzzer may be automatically stopped after an elapse of a predetermined time. [0079] Further, in the above embodiment, the configuration has been described that the headlamp is automatically turned off when the ignition-off state or the non-sitting state of the driver is continued for a predetermined time or more; however, the light of the headlamp may be weakened by reducing the supplied current in place of turn-off of the headlamp, or the headlamp may be turned off and instead a position lamp may be turned on. [0080] Fig. 9 is a block diagram showing the entire configuration of an engine starting/stopping control system according to another embodiment of the present invention, in which the same symbols as those described above designate the same or similar parts. In this embodiment, a power generated by the AC generator 72 is charged in two batteries 68A and 68B via the regulator/rectifier 67. The battery 68A, which is specialized for starting an engine, supplies a drive current to the starter motor 71 if a starter relay 62 is made conductive. The battery 68B supplies load currents via the main switch 73 to the various electrical equipment 74, the main control unit 60 and the like. [0081] In this way, since the battery 68A specialized for starting the engine is very small in power consumption and is usually kept in a full-charge state, it is possible to usually desirably start the engine irrespective of the charged amount of the battery 68B. [0082] Fig. 10 is a block diagram showing the configuration of an essential portion of the generator/motor 250 functioning as an engine assistor serving as engine starter which is one embodiment of the present invention. In this figure, the same symbols as described above designate the same or similar parts. [0083] A motor M of the generator/motor 250 has a rotor (not shown) connected to a crank shaft 201 of an engine 200. The rotational angle of the crank shaft 201 is detected by an angle sensor 49 and is supplied to a main control unit 60. The motor M includes, as described above, a generating coil 272 and a starting coil' 273 as stator coils; however, the operation in the case of using the starting coil 273 as the stator coil will be described in this embodiment. [0084] A brush type energization control means 902 receives the rotational motion of the crank shaft 201 and mechanically switches the contact between each stator coil (starting coil 273) of the motor M and a power supply line LI by means of brushes in accordance with the rotational angle of the crank shaft 201. As described in detail with reference to Fig. 5, the contact between each stator coil of the motor M and the power supply line is held upon starting of the engine and is released not upon starting of the engine by a governor mechanism 230. A brushless type energization control means 901 electrically switches the connection between each stator coil of the motor M and the power supply line LI in response to a control signal supplied from the main control unit 60. [0085] The main control unit 60 has a generation control unit 601 adapted to control the brushless type energization control means 901 for allowing the motor M to function as the generator, and an assist control unit 602 adapted to control the brushless type energization control means 901 for allowing the motor M to function as the engine assistor. [0086] When the engine 200 requires a torque assist, the assist control unit 602 controls the brushless type energization control means 901 in response to the rotational angle of the crank shaft 201 for carrying out the torque assist of the engine 200. At this time, the assist control unit 602 selects the stator coil to be excited, of the motor M on the basis of the rotational angle of the crank shaft 201 detected by the angle sensor 49, and determines the energization time thereof on the basis of the throttle opening detected by a throttle sensor 50. The brushless type energization control means 901 supplies an exciting current from a battery 68 to the stator coil selected by the assist control unit 602 for the determined energization time. [0087] Fig. 11 is a diagram showing the circuit configuration of one embodiment using a single-phase/six-pole motor as the motor M. In this figure, the same symbols as described above designate the same or similar parts. [0088] In a brushless type energization control means 901A, six pairs of power FETs, in each pair of which two power FETs are connected in series, are connected in parallel. The common connection portions of the FET pairs are respectively connected to one-ends of stator coils LI to L6 and commutator segments 267 of a commutator holder 265. An annular positive commutator segment 298 of the commutator holder 265 is connected to a positive electrode of the battery 68 via a starter relay 62, and an annular negative commutator segment 299 is directly connected to a negative electrode of the battery 68. [0089] With this configuration, if the rotational number of the engine, that is, the rotational number of the crank shaft 201 is low, as described above, a brush holder 262 is pushed on the commutator holder 265 side by the governor mechanism 230, so that the commutator segment 267 on one end side of the stator coil selected in accordance with the rotational angle of the crank shaft 201 and the commutator segment 267 on the other end side of the stator coil are sequentially connected to the positive commutator segment 298 and the negative commutator segment 299 by brushes 261 of the brush holder 262. Accordingly, the motor M functions substantially as a brush motor. [0090] On the other hand, if the rotational number of the crank shaft 201 becomes high after termination of the starting of the engine, the brush holder 262 is separated from the commutator holder 265. In such a state, if the assist control begins by the assist control unit 602 of the main control unit 60, each FET of the brushless type energization control means 901A is subjected to chopping control based on a duty ratio corresponding to the throttle opening detected by the throttle sensor 50 so that an exciting current is selectively supplied from the battery 68 to the stator coil selected in accordance with the rotational angle of the crank shaft 201 detected by the angle sensor 49. It should be noted that the inverter action by the brushless type energization control means 901A for the single-phase/six-pole motor is known and therefore the description thereof is omitted. [0091] In this embodiment, since the current is supplied to the stator coil by the brush mechanism at a timing for controlling a relatively large exciting current, for example, upon starting of the engine, it is not required to increase the capacities of the FETs of the brushless type energization control means 901A. Further, since the current is supplied to the stator coil by the power FETs of the brushless type energization control means 901A at a timing for controlling a relatively small exciting V current, for example, upon engine assist, that is, the brush mechanism can be kept in a non-contact state, it is possible to prevent occurrence of wear and deterioration of the brushes 261. [0092] Incidentally, a general brushless motor requires a high accurate angle sensor because the absolute angle must be detected upon starting of the brushless motor. In this embodiment, however, when the motor is started as the brushless motor, the rotor of the motor has been already rotated, and accordingly, the rotor does not require accurate angle detection, that is, it does not require a high accurate angle sensor. That is to say, it is sufficient for the motor functioning as the brushless motor in this embodiment to be provided with an inexpensive angle sensor with a simple structure. [0093] Fig. 12 is a diagram showing the circuit configuration of another embodiment using a three-phase motor as the motor M. In this figure, the same symbols as described above designate the same or similar parts. [0094] In a brushless type energization control means 901B, three pairs of power FETs, in each pair of which two power FETs are connected in series, are connected in parallel. The common connection portions of the FET pairs are connected to one-ends of stator coils LI to L3 and commutator segments 267 of a commutator holder 265, respectively. An annular positive commutator segment 298 is connected to a positive electrode of a battery 68 via a starter relay 62, and an annular negative commutator segment 299 is directly connected to a negative electrode of the battery 68. [0095] With this configuration, if the rotational number of the engine, that is, the rotational number of the crank shaft 201 is low, as described above, a brush holder 262 is pushed on the commutator holder 265 side by a governor mechanism 230, so that the commutator segment 267 on one end side of the stator coil selected on the basis of the rotational angle of the crank shaft 201 and the commutator segment 267 on the other end side of the stator coil are sequentially connected to the positive commutator segment 298 and the negative commutator segment 299 by brushes 261 of a brush holder 262. [0096] On the other hand, if the rotational number of the crank shaft 201 becomes high, the brush holder 262 is separated from the commutator holder 265. In such a state, each FET of the brushless type energization control means 901B is subjected to chopping control based on a duty ratio corresponding to the throttle opening so that an exciting current is supplied from the battery 68 to the specified stator coil in accordance with the detected rotational angle of the crank shaft 201. It should be noted that the inverter action by the brushless type energization control means 901B for the three-phase motor is also known and therefore the description thereof is omitted. [0097] In this embodiment, since the current is supplied to the stator coil by the brush mechanism at a timing for controlling a relatively large exciting current, for example, upon starting of the engine, it is not required to increase the capacities of the FETs of the brushless type energization control means 901B. Further, since the current is supplied to the stator coil b£ the power FETs of the brushless type energization control means 901B at a timing for controlling a relatively small exciting current, for example, upon engine assist, that is, the brush mechanism can be kept in a non-contact state, it is possible to prevent occurrence of wear and deterioration of the brushes 261. [0098] In this embodiment, the generator/motor 250 includes the generating coil 272 and the starting coil 273 as the stator coils, wherein the function as the starter motor 71 can be achieved by the brush motor using the starting coil 273 as the stator coil, the function as the assist motor 70 can be achieved by the brushless motor using the starting coil 273 as the stator coil, and the function as the ACG 72 can be achieved by the brushless motor using the generating coil 272 as the stator coil. [0099] However, if the main control unit 60 controls the switching timing of each FET of the brushless type energizatin control means 901B to allow the starting coil 273 to function as the generating coil during running of the vehicle in which the generator/motor 250 does not function as the assist motor 70, the generating coil 272 can be omitted. At this time, the main control unit 60 detects a terminal voltage of the battery 68 by a suitable means, and controls the duty ratio of a pulse signal for chopping control of each FET in such a manner that the output voltage from the generator/motor 250 exceeds the terminal voltage of the battery 68 by a specific value. [0100] The assist control by the assist control unit 602 will be described with reference to Fig. 13. [0101] As described above, in the vehicle on which the engine stopping/starting control unit is mounted, when the driver opens the throttle grip at a time to, the generator/motor 250 functions as the starter motor to start the engine. After that, as the rotational number Ne of the engine increases up to a rotational number Nin for clutch engagement at a time t2, the vehicle moves and at the same time the assist control unit 602 starts the control of the brushless type energization control means 901 to start the engine assist by the generator/motor 250. As a result, the drive wheel receives a total torque (TE + TM) of a torque TE generated by the engine and a torque TM generated by the generator/motor 250.' [0102] As the rotational number of the engine further increases, the engine can generate a sufficient torque, and accordingly, in this embodiment, the assist amount by the generator/motor 250 is gradually decreased with the increased rotational number of the engine, and the assist control is terminated when the rotational number of the engine reaches a predetermined reference rotational number Nref. [0103] As described above, in this embodiment, since the torque assist is performed until the rotational number of the engine reaches the reference rotational number Nref at which the engine can generate a sufficient torque after clutch engagement, it is possible to improve the movement feeling in combination with energy-saving. [0104] In the above embodiment, description is made by example of the vehicle including the engine stopping/starting control function; however, the present invention can be applied to a related art vehicle including no engine stopping/starting control function. In this case, as shown in Fig. 14, it may be desirable to perform the assist control after the rotational number of the engine reaches the rotational number Nin for clutch engagement. [0105] Fig. 15 is a diagram showing a target assist torque Ttag generated by the generator/motor 250 with a throttle opening  th and a rotational number Ne of the engine taken as parameters. The target torque Ttag is set to be increased with the throttle opening  th. [0106] The torque TM generated by the generator/motor 250 is dependent on the duty ratio of a pulse signal for switching control of each FET of the brushless type energization control means 901. Accordingly, by controlling the duty ratio of a pulse signal for switching control of each FET as a function of the throttle opening  th and the rotational number Ne of the engine in place of the above target torque, it is possible to obtain a desired engine assist. [0107] [Effect of the Invention] According to the present invention, since the current is supplied to a stator coil by a brush mechanism at a timing for controlling a relatively large exciting current, for example, upon starting of the engine, it is not required to increase the capacities of power FETs for switching. Further, since the current is supplied to a stator coil by the power FETs for switching at a timing for controlling a relatively small exciting current, for example, upon engine assist, that is, the brush mechanism can be kept in the non-contact state, it is possible to prevent occurrence of wear and deterioration of brushes. [Explanation of Symbols] 2: body front, 3: body rear, 4: floor portion, 6: down tube, 7: main pipe, 8: seat, 11: handlebar, 12: front fork, 13: front wheel, 15: bracket, 16: link member, 17: swing unit, 18: hanger bracket, 21: rear wheel, 22: rear cushion, 23: intake pipe, 24: carburetor, 25: air cleaner, 26: main stand, 27: kick shaft, 28: kick arm, 29: kick pedal, 200: engine, 201: crank shaft, 202: crank case, 203: cylinder block, 204: cylinder head, 206: ignition plug, 210: belt drive pulley, 211: boss, 212: V-belt, 250: generator/motor, 251: inner rotor, 300: operational mode switching unit, 400: starter relay control unit, 500: by-starter control unit, 600: indicator control unit, 700: ignition control unit, 800: headlamp control unit WE CLAIM: 1. An engine assistor serving as an engine starter, including a motor (M) having a rotor (251) connected to a crank shaft (201) of an engine (200) and a stator (270) having multi-phase windings and which performs both engine starting and engine torque assist by said motor (M), comprising: a rotational angle detector (49) for detecting a rotational angle of said crank shaft (201) and generating an angle signal; a brushless type energization controller (901) for electrically switching the connection between each stator coil (273) of said motor (M) and a power supply line (L1) on the basis of the angle signal detected by said rotational angle detector (49); a brush type energization controller (902) for receiving the rotational motion of said crank shaft (201) and mechanically switching the contact between each stator coil (273) and the power supply line (L1) by means of brushes in accordance with the rotational angle of said crank shaft (201); and an assist controller (602) for biasing said brushless type energization controller (901) to drive said motor (M); wherein said brush type energization controller (902) holds the contact between each stator coil (273) and the power supply line (L1) upon engine starting and releases the contact between each stator coil (273) and the power supply line (L1) not upon engine starting. 2. An engine assistor serving an engine starter as claimed in claim 1, wherein said brush type energization controller (902) comprises: a commutator holder (265) for holding commutator segments (267) which are connected to respective stator coil (273) and the power supply line (L1) and which are arranged around said crank shaft (201), said commutator holder (265) being rotatable in synchronization with said crank shaft (201); a brush holder (262) for holding brushes (261) arranged around said crank shaft (201), said brushes (261) being adapted to connect said commutator segment (267) of said stator coil (273) selected in accordance with the rotational angle of said crank shaft (201) to said commutator segment (267) of the power supply line (L1); and a governor mechanism (230) for bringing said commutator segments (267) of said commutator holder (265) in contact with said brushes (261) of said brush holder (262) by an elastic force during a period in which said crank shaft (201) is rotated at a speed less than a specific value, and separating said commutator segments (267) from said brushes (261) against the elastic force when said crank shaft (201) is rotated at a speed equal to or more than the specific value. 3. An engine assistor serving as an engine starter as claimed in claim 1 or 2, wherein said brushless type energization controller (901) is adapted to be biased by a power generation controller (610) so as to allow said motor (250) to function as a generator. 4. An engine assistor serving as an engine starter as claimed in claim 1, for use in a vehicle having a belt type continuously variable transmission and a centrifugal clutch. 5. An engine assistor serving as an engine starter substantially as herein described with reference to the accompanying drawings.

Full Text

[0001]
The present invention relates to an engine assisto serving as engine starter for performing engine starting and engine torque assist by means of a common motor, and particularly to an engine assistor serving as engine starter in which the motor substantially functions
r'
selectively as a brush motor or a brushless motor.

[0002]
—*
[Prior Art]
A vehicle improved from the viewpoint of environmental pollution measure and energy-saving has been disclosed, for example, in Japanese Patent Laid-open No. Hei 4-303030, which vehicle mounts an engine and a motor as drive sources and includes an engine assistor for compensating for an insufficient engine torque with the motor.
[0003] )
[Problem to be Solved by the Invention]
A torque assist motor does not require a large
drive torque and receives a relatively small current, but it is driven for a relatively long period of time. A non-contact type brushless motor excellent in durability is used for such a torque assist motor. On the other hand, an engine starter is driven for a short period of time, but it requires a large drive torque. A brush motor suitable for control of a large current is used for such an engine starter.
[0004]
Accordingly, in the case where engine starting and engine torque assist are performed by a common motor, if a brushless motor is used as the common motor, the motor must be enlarged to obtain a sufficient drive torque upon starting of the engine. On the other hand, if a brush motor is used as the common motor, such a brush motor is effective to obtain a sufficient torque without increasing the size of the motor; however, since brushes are usually slid during running of the vehicle, the brush portion is significantly deteriorated.
[0005]
An object of the present invention is to solve the above problem of the prior art, and to provide an engine assistor serving as engine starter including a generator/motor which functions as a brush motor upon

starting of the engine and which functions as a brushless motor upon torque assist other than upon starting of the engine, and upon power generation.
[Means for Solving the Problem]
According to the present invention there is provided an engine assistor
serving as an engine starter, including a motor (M) having a rotor connected to a crank shaft of an engine and a stator having multi-phase windings
and which performs both engine starting and engine torque assist by
said motor (M
a rotational angle detector for detecting a rotational angle of said crank shaft and generating an angle signal;
a brushless type energization controller for electrically switching the connection between each stator coil of said motor (M) and a power supply line (LI) on the basis of the angle signal detected by said rotational angle detector;
a brush type energization controller for receiving the rotational motion of said crank shaft and mechanically switching the contact

between each stator coil and the power supply line (L1) by means of brushes in accordance with the rotational angle of said crank shaft; and
an assist controller for biasing said brushless type energization controller to drive said motor (M);
wherein said brush type energization controller holds the contact between each stator coil and the power supply line (L1) upon engine starting and releases the contact between each stator coil and the power supply line (L1) not upon engine starting.
With this configuration, since the selection/switching of a stator coil to be excited is performed by the brush mechanism at a timing for controlling a relatively large exciting current, for example, upon starting of the engine, it is not required to increase the capacity of each switching means constituting the brushless type energization control means. On the other hand, the selection/switching of a stator coil to be excited is preformed by the brushless type energization control means at a timing in which the engine is rotated at a rotational speed equal to or more than a specific value, for example upon engine assist, that is, the brush mechanism can be kept in the non-contact state, it is possible to prevent occurrence of wear and deterioration of brushes.

[Brief Description of the Drawings] [Fig. 1]
A side view of the entire configuration of a scooter-type motorcycle mounted with an engine stopping/starting control system of the present invention. [Fig. 2]
A plan view of an instrument and its neighborhood of the scooter-type motorcycle. [Figs. 3a and 3b]

Views typically showing the structure of a hinge portion of the front portion of a seat. [Figs. 4a and 4b]
Sectional views showing a main portion of a throttle grip. [Fig. 5]
A sectional view, taken on line II-II of Fig. 1, showing an internal combustion engine. ,• [Fig. 6]
A block diagram showing the entire configuration of one example of a starting/stopping control system. [Fig. 7]
A block diagram showing the function of a main control unit. [Fig. 8]
A diagram showing main operations of the main control unit. [Fig. 9]
A block diagram showing the entire configuration of another example of a starting/stopping control system. [Fig. 10]
A block diagram showing the configuration of an essential portion of a generator/motor functioning as an engine assistor serving as engine starter according to

one embodiment of the present invention. [Fig. 11]
A block diagram showing one example in which the
engine assistor serving as engine starter is applied to a
•single-phase/six-pole motor. [Fig. 12]
A block diagram showing one example in which the engine assistor serving as engine starter is applied to a three-phase motor. [Figs. 13a to 13c]
Diagrams showing one example of an assist control method.
[Figs. 14a to 14c]
Diagrams showing another example of the assist control method. [Fig. 15]
A diagram showing an assist amount by the
s~
generator/motor as functions of a throttle opening and a rotational number of the engine.

[0008]
[Embodiments of the Invention]
Hereinafter, the present invention will be described in detail with reference to the drawings. Fig. 1 is a general side view of a scooter-type motorcycle 1 mounted with an engine stopping/starting control system according to one embodiment of the present invention. [0009]
A body front 2 is connected to a body rear 3 via a low level floor 4. A body frame constituting a skeleton
of a vehicular body is basically composed of a down tube

6 and a main pipe 7. A fuel tank and a containing box (both not shown) are supported by the main pipe 7, and a seat 8 is arranged over the fuel tank and containing box. [0010]
At the body front 2, a handle bar 11 is rotatably supported by a steering head 5 in such a manner as to extend upward therefrom and a front fork 12 is rotatably supported by the steering head 5 in such a manner as to extend downward therefrom. A front wheel 13 is rotatably supported by the lower ends of the front fork 13. The upper portion of the handlebar 11 is covered with a handle cover 33 serving as an instrument board. A bracket 15 is projectingly provided on the lower end of a rising portion of the main pipe 7, and a swing unit 17 is swingably connected to and supported by the bracket 15 via a link member 16.

[0011]
A single-cylinder/two-stroke internal combustion engine 200 is mounted on the front portion of the swing unit 17. A belt type continuously variable transmission 35 provided extending rearward from the engine 200, a reduction mechanism 38 is provided on the rear portion of the transmission 35 via a centrifugal clutch. A rear wheel 21 is rotatably supported by the reduction mechanism 38. A rear cushion 22 is interposed between the upper end of the reduction mechanism 38 and the upper bend portion of the main pipe 7. A carburetor 24 connected to an intake pipe 23 extending from the upper portion of a cylinder head of the engine 200 and an air cleaner 25 connected to the carburetor 24 are arranged over the swing unit 17.
[0012]
A main stand 26 is pivotably mounted on a hanger bracket 18 projectingly provided on the lower portion of a unit swing case 31. The base end of a kick arm 28 is fixed to a kick shaft 27 projecting from a transmission case cover 36 of the belt type continuously variable transmission 35. A kick pedal 29 is provided at the leading end of the kick arm 28.
[0013]

Fig. 2 is a plan view of an instrument panel and its neighborhood of the motorcycle 1. A speed meter 91, a stand-by indicator 56, and a battery indicator 76 are provided in an instrument panel 90 mounted to the handle cover 33. As will be described in detail later, the stand-by indicator 56 flashes when the engine is stopped during control of stopping/starting of the engine for warning the driver of the fact that the present state is a state in which the engine will be started to move the vehicle directly after a throttle is opened. The battery indicator 76 is turned on if a battery voltage is lowered for warning the driver of the lack of charged power of the battery.
[0014]
The handle cover 33 is also provided with an idle switch 53 for permitting or restricting idling and a starter switch 58 for starting a starter motor. A throttle grip 92 and a brake lever 93 are provided at the right end portion of the handlebar 11. It should be noted that while a horn switch, a winker switch and the like are provided on the roots of the right and left throttle grips like the related art motorcycle, they are not shown in Fig. 2 .
[0015]

Figs. 3a and 3b typically show the structure of a hinge portion provided at the front of the seat 8, which hinge portion is designated by a round mark depicted by the broken line in Fig. 1. In this embodiment, a hinge member 81, which is fixed on the front of the back face of the seat 8, has an opening 82 elongated in the vertical direction. A hinge shaft 85 fixed on the vehicular body side passes through the elongated opening 82, so that the seat 8 is supported swingably around the hinge shaft 85 and movably in the vertical direction. A coil spring 83 for elastically biasing a pressing piece 83a and a sitting switch 54 are provided on the vehicular body side opposed to the back face of the hinge member 81. [0016]
With this configuration, in the non-sitting state in which a driver is not sit in the seat 8, as shown in Fig. 3a, since the seat 8 is pushed up by the coil spring 83 until the hinge shaft 85 is brought in contact with the lower end of the elongated opening 82, the sitting switch 54 is turned into the OFF state.
[0017]
On the contrary, in the sitting state in which the driver is sit in the seat 8, as shown in Fig. 3b, since the seat 8 is pushed down against the elastic force of

the coil spring 83, the sitting switch 54 is turned into the ON state. Accordingly, it can be confirmed whether or not the driver is sitting in the seat 8 by keeping watch on the ON/OFF state of the sitting switch 54. Also, in this embodiment, since the sitting switch 54 is provided on the front side of the seat 8, even if the driver is short in stature, it can be certainly detected whether or not he is sit in the seat 8.
[0018]
Fig. 4a is a sectional view showing a main portion of the throttle grip 92, and Fig. 4b is a sectional view taken on line I-I of Fig. 4a. As shown in Fig. 4a, a throttle grip main body 182 is turnably inserted around a handle pipe 181 and is covered with a grip cover 183. The throttle grip main body 182 has a flange 182a which projects from the circumference of the throttle grip main body 182. As shown in Fig. 4b, one end 185a of a throttle wire 185 is locked to the flange 182a. The throttle grip main body 182 is usually biased on the accelerator closing side by the elastic force of a spring 184. When the throttle grip main body 182 is twisted in the opening direction against the elastic force of the spring 184, the throttle wire 185 is twisted inward to open the throttle.

[0019]
In this embodiment, the throttle grip 92 has a throttle switch 52 which closes (or opens) a contact when the throttle grip is full closed and which opens (or closes) the contact when the throttle grip is opened by a predetermined angle. In other words, the throttle switch 52 opens (or closes) the contact in an angle range less than a play angle 9 , that is, before the' throttle actually begins to be opened. This allows the throttle switch 52 to be turned on without opening the throttle. Accordingly, the engine can be operated by the intention of the driver even in the stopping state of the vehicle. [0020]
The throttle grip main body 182 is additionally applied with the elastic force of a throttle spring (not shown) when the opening angle of throttle grip main body 182 reaches an angle (> 0 ) at which the throttle actually begins to be opened, and accordingly, the opening/closing operation of the throttle switch 52 only in the angle range less than the play angle can be easily performed. [0021]
Fig. 5 is a sectional view, taken on line II-II of Fig. 1, showing the engine 200. The engine 200 includes a

crank case 202 divided into right and left crank cases 202R and 202L for rotatably supporting a crank shaft 201 extending from right to left in the horizontal direction, and a cylinder block 203 and a cylinder head 204 which are sequentially stacked on the crank case 202. The cylinder block 203 has an exhaust passage (not shown), and it also has scavenging passages 205 each having a scavenging port opened in a cylinder bore of the cylinder block 203 so that the cylinder block 203 is communicated to a crank chamber of the crank case 202.
[0022]
An ignition plug 206 is fitted in the cylinder head 204 in such a manner as to be directed toward a combustion chamber. The cylinder head 204 and the cylinder block 203 are covered with a fan shroud 207 except for the exposed portion of the ignition plug 206. The left crank case 202L serves as a belt-type continuously variable transmission chamber case. A belt drive pulley 210 is rotatably provided around the crank shaft 201 passing through the left crank case 202L.
[0023]
The belt drive pulley 210 has a fixed side pulley half 210L and a movable side pulley half 210R. The fixed side pulley half 210L is fixed to the left end portion of

the crank shaft 201 via a boss 211. The movable side pulley half 210R, positioned on the right side of the fixed side pulley half 210L, is spline-fitted to the crank shaft 201 to be movable close to or apart from the fixed side pulley half 210L. A V-belt 212 is wound between both the pulley halves 210L and 210R. [0024]
A cam plate 215, positioned on the. right side of the movable side pulley half 210R, is fixed to the crank shaft 201. A slide piece 215a provided at the outer peripheral end of the cam plate 215 is slidably engaged with a cam plate slide boss 210Ra which is axially formed at the outer peripheral end of the movable side pulley half 210R. The side surface, on the cam plate 215 side, of the movable side pulley half 210R is tapered toward the cam plate 215 side, and dry weight rollers 216 are contained in a state being held between the inner surface of the taper portion of the movable side pulley half 210R and the cam plate 215.
[0025]
As the rotational speed of the crank shaft 201 is increased, the dry weight rollers 216, which are held between the movable side pulley half 210R and the cam plate 215 and are rotated therewith, are moved in the

centrifugal direction by the centrifugal force applied thereto. As a result, the movable side pulley half 210R is pushed by the dry weight rollers 216 to be moved leftward, that is, close to the fixed side pulley half 210L, so that the V-belt 212 held between both the pulley halves 210L and 210R is moved in the centrifugal direction. This increases the winding radius of the V-belt 212. The V-belt 212 is wound around' the belt drive pulley 210 and also around a belt driven pulley (not shown) provided on the rear side, so that a power is automatically adjusted and is transmitted to the reduction mechanism provided on the rear side via a centrifugal clutch, to thus drive a rear wheel.
[0026]
A transmission case cover 220, which extends rearward from the belt drive pulley 210 located on the front side, covers from left the belt-type continuously variable transmission chamber. The kick shaft 27 turnably passes through and is supported by the front portion of the transmission case cover 220. A drive helical gear 222 is fitted to the inner end portion of the kick shaft 27 and is biased by a return spring 223. A slide shaft 224 coaxial with the crank shaft 201 is rotatably, axially and slidably supported by the inner surface of the front

portion of the transmission case cover 220. A driven helical gear 225 is formed around the slide shaft 224 and meshed with the drive helical gear 222. A ratchet wheel 226 is fixed at the right end of the driven helical gear 225. The ratchet wheel 226, drive helical gear 222, and driven helical gear 225 are biased leftward by a friction spring 227. [0027]
A ratchet facing to the ratchet wheel 226 is formed on the boss 211 on the crank shaft 201 side. Both the ratchet and ratchet wheel 226 can be moved close to or apart from each other by sliding motion of the slide shaft 224. When the kick pedal 29 is actuated and the kick shaft 27 is rotated against the return spring 223, the drive helical gear 222 integrated with the kick shaft 27 is rotated, and the driven helical gear 225 meshed with the drive helical gear 222 is slid rightward against the biasing force of the friction spring 227 while being rotated together with the slide shaft 224, so that the ratchet wheel 226 is meshed with the ratchet of the boss 211 to forcibly rotate the crank shaft 201, thus starting the internal combustion engine 200.
[0028]
The right crank case 202R, formed into an
approximately cylindrical shape, extends rightward from a main bearing 209 for rotatably supporting the crank shaft 201. The crank shaft 201 projects along the center axis of the right crank case 202R. An
assistor/starter/generator 250 (hereinafter, sometimes referred to simply as "generator/motor") having a combination of a function as an assist motor, a function as a starter motor, and a function of an AC generator (ACG) is disposed in the cylinder of the right crank case 202R.
[0029]
An inner rotor (rotational inner magnetic type rotor) 251 is fitted around a taper portion formed at the leading end of the crank shaft 201 and is fixed thereto with a nut 253. The inner rotor 251 is thus rotated together with the crank shaft 201. Six grooves, each being formed in an arcuate shape in cross - section, are formed in the outer peripheral surface portion of the inner rotor 251. A magnet 271 made from a neodymium-iron-boron alloy is fitted in each of the six grooves.
[0030]
An outer stator 270 is arranged around the outer periphery of the inner rotor 251 in such a manner that the outer peripheral edge thereof is fastened to and

supported by a cylindrical wall 202a of the crank case 202 with a bolt 279. A stator core of the outer stator 270 is composed of steel sheets laminated to each other, and a power generating coil 272 and a starting coil 273 as stator coils are wound around a plurality of teeth extending toward the center from the annular portion of the outer periphery of the stator core. The generating coil 272 and starting coil 273 are wound' around the teeth in such a manner as to be offset on the inner side in the direction toward the crank shaft. In other words, the amounts, projecting outward in the axial direction of the crank shaft 201, of the coils 272 and 273 are made small. [0031]
The power generating coil 272 and the starting coil 273, which project inward rather than outward in the axial direction within the cylindrical wall 202a of the crank case 202, form an annular inner space in which a rectifying brush mechanism 263 is provided. A brush holder 262, through which the crank shaft 201 passes in the inner space, is fitted to the crank shaft 201 in such a manner as not to be permitted in its relative rotation in the circumferential direction and to be permitted only in its sliding motion in the axial direction. A spring 274 is interposed between the brush holder 262 and the
inner rotor 251 for biasing the brush holder 262 inward
in the axial direction.
[0032]
A plurality of brushes 261 are provided at specific positions on the inner surface of the brush holder 262 in such a manner as to project therefrom by the elastic forces of springs. A commutator holder 265 facing to the inner surface of the brush holder 262 is, provided in such a manner that its center is penetrated by the crank shaft 201 and its outer peripheral edge is fixedly supported by portions, largely projecting inward in the axial direction, of the power generating coil 272 and the starting coil 273.
[0033]
Commutator pieces 267 are concentrically arranged at specific positions on the surface, facing to the brush holder 262, of the commutator holder 265. The brush holder 262, which is rotated together with the crank shaft 201, is moved close to or apart from the fixed commutator holder 265. When the brush holder 262 is moved close to the commutator holder 265, each brush 261 is brought in contact with the corresponding commutator piece 267.
[0034]

The outer portion, in the axial direction of the crank shaft 201, of the inner rotor 251 has an inner cylindrical portion 231 covering the surroundings of the nut 253 screwed in the leading end of the crank shaft 201 and an outer cylindrical portion 232 concentrically covering the inner cylindrical portion 231. Both the cylindrical portions 231 and 232 extend axially outward, to constitute a governor mechanism 230. r-To be more specific, the inner peripheral surface of the outer cylindrical portion 232 is tapered to constitute a governor outer; a governor inner 233 is axially slidably fitted around the outer periphery of the inner cylindrical portion 231; and balls 234 as a governor weight are interposed between the governor inner 233 and the outer cylindrical portion 232.
[0035]
A connecting shaft, 235 with its one end fixed to the axially movable governor inner 233 of the governor mechanism 230 passes through the inner rotor 251 in parallel to the crank shaft 201, and the leading end of the connecting shaft 235 is fitted to the brush holder 262. In this way, the connecting shaft 235 connecting the governor inner 233 to the brush holder 262 allows both the governor inner 233 and the brush holder 262 to be

moved together with each other in the axial direction of
the crank shaft 201.
[0036]
When the crank shaft 201 is stopped, the brush holder 262 is moved inward in the axial direction by the biasing force of the spring 223 to bring the brushes 261 in contact with the commutator pieces 267. In this state, if a current is supplied from the battery, it flows to the starting coil 273 by way of the contact between the Drushes 261 and the commutator pieces 267, to generate a rotational torque applied to the inner rotor 251. The rotation of the inner rotor 251 rotates the crank shaft 201, thereby starting the engine 200. That is to say, the generator/motor 250 functions as a brush motor with the starting coil 273 taken as the stator coil.
[0037]
As the rotational number of the engine is increased, the balls 234 are moved, by the centrifugal force, in the outer peripheral direction on the inner tapered surface of the outer cylindrical portion 232, so that the governor inner 233 is slid outward in the axial direction. At this time, the brush holder 262 integrated with the connecting shaft 235 is moved outward in the axial direction, and when the rotational number of the engine

exceeds a specific value, the brushes 261 are automatically separated from the commutator pieces 267. After that, the charging to the battery is performed by the power generating coil 272. That is to say, the generator/motor 250 functions as a brushless motor with the starting coil 273 taken as the stator coil. [0038]
An annular disk-like rotor 240 for" detecting a crank angle is provided on the outer cylindrical portion 232 constituting the main part of the governor mechanism 230 in such a manner that its inner peripheral edge is integrally fitted to the edge portion of the outer cylindrical portion 232. An angle sensor 49 is arranged at a specific position in the vicinity of the outer peripheral edge of the rotor 240. The angle sensor 49 detects serrations formed on the outer peripheral edge of the rotor 240 rotated integrally with the crank shaft 201 via the inner rotor 251, to determine the crank angle. The annular disk-like rotor 240 covers from outside the power generating coil 272 and the starting coil 273 of the outer stator 270. A fan member 280 for forcibly air-cooling the internal combustion engine is integrally provided on the outer side of the rotor 240 in the axial direction.

[0039]
The base of a central cone portion 280a of the fan member 280 is fixed on the outer cylindrical portion 232 of the inner rotor 251 with a bolt 246. A fan 280b provided on the outer periphery of the central cone portion 280a is erected outside the rotor 240. The fan member 280 is covered with a fan cover 281. [0040]
According to the generator/motor for a vehicle in this embodiment, as described above, the rectifying brush mechanism 261 is disposed inward from the inner rotor 251 in the axial direction and the governor mechanism 230 separated from the rectifying brush mechanism 261 is disposed outward from the inner rotor 251 in the axial direction. Accordingly, the amount, protruded outward in the axial direction of the crank shaft, of the generator/starter can be suppressed. [0041]
Further, since the power generating coil 272 and the starting coil 273 are wound around the yokes of the stator core of the outer stator 270 in such a manner as to be offset inward in the axial direction, that is, to make small the amounts, projecting outward in the axial direction, of the coils 272 and 273, the rotor 240 and

the fan member 280 can be located relatively inward in the axial direction to thereby further make small the amount, projecting outward in the axial direction, of the generator/starter. [0042]
Outside air introduced from an outside air suction port 281a of the fan cover 281 by rotation of the fan 280b is spread toward the outer periphery along the central cone portion 280a; however, since the rotor 240 cuts off the introduced air and prevents permeation of the outside air to the generator/motor 250 side, the outside air less permeates to the rectifying brush mechanism 261 located at the back of (axially inward from) the generator/motor 250. This prevents the rectifying brush mechanism 261 from being affected by dust contained in the outside air. [0043]
Fig. 6 is a block diagram showing the entire configuration of a starting/stopping control system in the engine 200 including the generator/motor 250 for directly rotating the crank shaft 201 as described above. In this figure, the same symbols as those described above designate the same or similar parts.
[0044]

The engine stopping/starting system in this embodiment includes an operational mode in which idling is restricted and an operational mode in which idling is permitted. To be more specific, the system includes an "engine-stopping/vehicle-moving mode (idling restricting mode)" in which when the vehicle is stopped, the engine is automatically stopped, and when the throttle grip is actuated in the stopping state of the engine, the engine is automatically re-started to move the vehicle, and the system also includes an "engine-starting mode (idling permitting mode)" in which idling is permitted for warming-up upon starting of the engine.
[0045]
The generator/motor 250 is coaxially connected to the crank shaft 201 of the engine 200. The generator/motor 250 is composed of an assist motor 70, a starter motor 71 and an AC generator (ACG) 72. A power generated by the AC generator 72 is charged in a battery 68 via a regulator/rectifier 67. When a starter relay 62 is made conductive, the battery 68 supplies a drive current to the starter motor 71 and also supplies load currents to various electrical equipment 74 and a main control unit 60 via a main switch 73.
[0046]

To the main control unit 60 is connected an angle sensor 49 for detecting a rotational angle of the engine, a throttle sensor 50 for detecting the opening of the throttle, an Ne sensor 51 for detecting the rotational number Ne of the engine, the throttle switch 52 which closes the contact when the throttle opening exceeds a predetermined value, an idle switch 53 for permitting or restricting idling of the engine 200, the sitting switch 54 which closes the contact when a driver sits in the driver's seat, a vehicular speed sensor 55 for detecting a vehicular speed, the stand-by indicator 56 which flashes upon stopping of the vehicle in the engine-stopping/vehicle-moving mode to be described later, a headlamp switch 57 for turning on/off the headlamp 69, the starter switch 58 for driving the starter motor 71 of the generator/motor 250 to start the engine 200, a stop switch 59 which closes the contact in response to a braking operation, and the battery indicator 76 which is turned on when the voltage of the battery 68 is equal to or less than a predetermined value (for example, 10 V) for warning the driver of the lack of charging power in the battery.
[0047]
To the main control unit 60 are also connected an

ignition control device (including an ignition coil) 61 for igniting the ignition plug 206, a control terminal of the starter relay 62 for supplying a power to the starter motor 71, a control terminal of a headlamp relay 63 for supplying a power to the headlamp 69, a control terminal of a by-starter relay 64 for supplying a power to the by-starter 65 mounted to the carburetor 66, and a buzzer 75 for generating an alarm for giving caution to the driver before the driver goes away from the vehicle without turning off the main switch 73 or the headlamp 69 is automatically turned off. [0048]
Fig. 7 is a block diagram for concretely showing the configuration of the main control unit 60, in which the same symbols as those described above designate the same or similar parts. Fig. 8 is a diagram showing main operations of the main control unit 60.
[0049]
An operational mode switching unit 300 switches, the operational mode of the engine stopping/starting control system of the present invention into either the "engine-starting mode" in which idling is permitted or the "engine - stopping/vehicle-moving mode" in which idling is restricted, in accordance with the ON/OFF state of the

idle switch 53 and the state of the vehicle. [0050]
In the operational mode switching unit 300, a signal indicating the ON/OFF state of the idle switch 53 is inputted in both an operational mode signal outputting unit 301 and an inverter 302. The signal indicating the ON/OFF state of the idle switch 53 indicates an "L" level in the OFF state (restriction of idling) 'of the idle switch 53 and an "H" level in the ON state (permission of idling) of the idle switch 53. The inverter 302 reversely outputs the signal indicating the ON/OFF state of the idle switch 53. [0051]
A vehicular speed continuation discriminating unit 303, which includes a timer 303a, outputs a signal of "H" level when a vehicular speed equal to or more than a predetermined value is detected for a predetermined time or more. An AND circuit 304 outputs a logical product of the output signal from the discriminating unit 303 and the output signal from the inverter 302 to the operational mode signal outputting unit 301.
[0052]
When the main switch 73 is turned on, the operational mode signal outputting unit 301 starts the

"engine-starting mode" in which idling is permitted. If upon the "engine-starting mode", the output signal from the AND circuit 304 indicates the "H" level, that is, the idle switch 53 is turned off and the vehicular speed equal to or more than the predetermined value is detected for the predetermined time or more, the operational mode is shifted from the "engine-starting mode" to the "engine-stopping/vehicle-moving mode" in r-which idling is restricted. Also, if upon the "engine-stopping/vehicle-moving mode", the idle switch 53 is turned on again, the operational mode is shifted from the "engine-stopping/vehicle-moving mode" to the "engine-starting mode" . An operational mode signal S301 outputted from the operational mode signal outputting unit 301 indicates the "L" level during the "engine-starting mode" and the "H" level during the "engine-stopping/vehicle-moving mode". [0053]
A starter relay control unit 400 allows manual or automatic starting of the starter relay 62 under a specific condition in accordance with the operational mode. In the starter relay control unit 400, a detection signal outputted from the Ne sensor 51 is supplied to an idling-or-less discriminating unit 401. When the rotational number of the engine is equal to or less than

a specific idling rotational number (for example, 800 rpm) , the discriminating unit 401 outputs a signal of "H" level. An AND circuit 402 outputs a logical product of the output signal from the discriminating unit 401, the signal indicating the ON/OFF state of the stop switch 59, and the signal indicating the ON/OFF state of the starter switch 58. An AND circuit 403 outputs a logical product of the output signal from the AND circuit 402 and the reversal signal of the operational mode signal S301. [0054]
An AND circuit 404 outputs a logical product of the output signal from the idling-or-less discriminating unit 401, the signal indicating the ON/OFF state of the throttle switch 52, and the signal indicating the ON/OFF state of the sitting switch 54. An AND circuit 405 outputs a logical product of the output signal from the AND circuit 404 and the operational mode signal S301. An OR circuit 406 outputs a logical sum of the output signals from the AND circuits 403 and 405 to the starter relay 62. [0055]
With this configuration, since the operational mode signal S301 indicates the "L" level during the "engine-starting mode", the AND circuit 403 is turned into an

enable state. Accordingly, if the starter switch 58 is turned on by the driver when the rotational number of the engine is equal to or less than the idling rotational number and the stop switch 59 is turned on (during braking operation), the starter relay 62 is made conductive to thereby start the starter motor 71. [0056]
On the contrary, the AND circuit 4'05 is turned into an enable state during the "engine-stopping/vehicle-moving mode". Accordingly, if the rotational number of the engine is equal to or less than the idling rotational number and the sitting switch 54 is turned on (during sitting of the driver in the driver's seat) to open the throttle, the starter relay 62 is made conductive to start the starter motor 71. [0057]
In a by-starter control unit 500, the output signal from the Ne sensor 51 is inputted in an Ne discriminating unit 501. The Ne discriminating unit 501 outputs a signal of "H". level if the rotational number of the engine is equal to or more than a predetermined value, to close the by-starter relay 64. With this configuration, even in either of the above operational modes, it is possible to make rich the fuel when the rotational number of the

engine is equal to or more than the predetermined value. [0058]
In an indicator control unit 600, the output signal from the Ne sensor 51 is inputted in an Ne discriminating unit 601. The Ne discriminating unit 601 outputs a signal of "H" level if the rotational number of the engine is equal to or less than a predetermined value. An AND circuit 602 outputs a logical product of,-the signal indicating the ON/OFF state of the sitting switch 54 and the output signal from the Ne discriminating unit 601. An AND circuit 603 outputs a logical product of the output signal from the AND circuit 602 and the operational mode signal S301 to the stand-by indicator 56. The stand-by indicator 56 is turned off if the input signal indicates the "L" level, and flashes if the input signal indicates the "H" level. [0059]
To be more specific, the stand-by indicator 56 flashes upon stopping of the vehicle during the "engine-stopping/vehicle-moving mode", and accordingly, if the stand-by indicator 56 flashes, the driver can recognize that he is able to immediately move vehicle by actuating the accelerator even if the engine is stopped.
[0060]
An ignition control unit 700 permits or prohibits the ignition operation performed by the ignition control device 61 under a specific condition in accordance with each operational mode. In the ignition control unit 700, a detection signal outputted from the vehicular speed sensor 55 is inputted in a running discriminating unit 701. The running discriminating unit 701 outputs a signal of "H" level if it discriminates that the vehicle is in the running state on the basis of the detection signal. An OR circuit 702 outputs a logical sum of the output signal from the running discriminating unit 701 and the signal indicating the ON/OFF state of the throttle switch 52. An OR circuit 703 outputs a logical sum of the output signal from the OR circuit 702 and the reversal signal of the operational mode signal S301 to the ignition control device 61. The ignition control device 61 executes, if the input signal indicates the "H" level, the igniting operation for each specific timing, and it interrupts the igniting operation if the input signal indicates the "L" level.
[0061]
With this configuration, since the reversal signal of the operational mode signal S301 indicates the "H" level in the "engine-starting mode", the OR circuit 703 usually

outputs a signal of "H" level. Accordingly, the ignition control device 61 usually executes the igniting operation in the "engine-starting mode". On the contrary, in the "engine-stopping/vehicle-moving mode", the igniting operation is executed under such a condition that the vehicle is on running or the throttle is opened, while the igniting operation is prohibited if the vehicle is in the stopping state and the throttle is closed.
[0062]
A headlamp/buzzer control unit 800 automatically turns on/off the headlamp on the basis of the running state -of the vehicle or the driver sitting state in accordance with each operational mode, and generates as a buzzer sound an alarm for giving caution to the driver. [0063]
A non-sitting continuation discriminating unit 801 receives the signal indicating the ON/OFF state of the sitting switch 54. The non-sitting continuation discriminating unit 801 includes two timers 8011 and 8012 for counting a driver non-sitting time. When the timers 8011 and 8012 each count a specific time-out period, the non-sitting continuation discriminating unit 801 outputs a signal S9011 or S8012 of "H" level. In this embodiment, the time-out period set in the timer 8011 is 3 sec, and

the time-out period set in the timer 8012 is 1 sec. [0064]
A non-ignition continuation discriminating unit 802 includes two timers 8021 and 8022 for counting a non-ignition time. In the non-ignition state, the discriminating unit 802 immediately outputs a signal S8023 of "H" level. When the timers 8021 and 8022 each count a specific time-out period, the discriminating unit 802 outputs a signal S8021 or S8022 of "H" level. In this embodiment, the time-out period set in the timer 8021 is 3.5 min, and the time-out period set in the timer 8022 is 3 min. [0065]
An AND circuit 812 outputs a logical product of the output signal S8011 from the non-sitting continuation discriminating unit 801 and the output signal S8023 from the non-ignition continuation discriminating unit 802. An OR circuit 804 outputs a logical sum of the output signal S8021 from the non-ignition continuation discriminating unit 802 and the output signal from the AND circuit 812. An AND circuit 805 outputs a logical product of the output signal from the OR circuit 804 and the operational mode signal S301 to a reset terminal R of a flip-flop 810.
[0066]
An AND circuit 807 outputs a logical product of the signal indicating the ON/OFF state of the throttle switch 52 and the operational mode signal S301. An Ne discriminating unit 806 receives the output signal from the Ne sensor 51, and outputs a signal of "H" level if the rotational number of the engine is equal to or less than a predetermined value. An AND circuit 808 outputs a logical product of the output signal from the Ne discriminating unit 806 and the reversal signal of the operational mode signal S301. An OR circuit 809 outputs a logical sum of the output signals form the AND circuits 807 and 808 to a set terminal S of the flip-flop 810. An AND circuit 811 outputs a logical product of the output signal from a terminal Q of the flip-flop 810 and the signal indicating the ON/OFF state of the headlamp switch 57 to the headlamp relay 63. The headlamp relay 63 turns on the, headlamp 69 if it receives a signal of "H" level, and turns off the headlamp 69 if it receives a signal of "L" level. [0067]
With this configuration, in the "engine-starting mode", since the reversal signal of the operational mode signal S301 indicates the "H" level, the AND circuit 808 is turned into the enable state. Accordingly, if the

rotational number of the engine is equal to or more than the predetermined value, the flip-flop 810 is set, so that the headlamp is turned on if the headlamp switch 57 is turned on.
[0068]
In the "engine-stopping/vehicle moving mode", since the operational mode signal S301 indicates the "H" level, each of the AND circuits 805 and 807 is turned into the enable state. Accordingly, if the output signal from the OR circuit 804 indicates the "H" level, the flip-flop 810 is reset, to automatically turn off the headlamp.
[0069]
That is to say, the headlamp in the "engine-stopping/vehicle-moving mode" is turned off if the non-ignition state is continued for a time-out period (3.5 min in this embodiment) of the timer 8021 or more so that the output signal S8021 indicates the "H" level, or if the non-sitting state in the non-ignition state is continued for a time-out period (3 sec in this embodiment) of the timer 8011 or more so that the output signal from the AND circuit 812 indicates the "H" level.
[0070]
As a result of examination by the present inventors, it is revealed that a vehicle stopping time for waiting

for a signal light (blue) or a chance for right-turning in an intersection is substantially in a range of 30 sec to 2 min. Accordingly, a vehicle stopping state after an elapse of the above vehicle stopping time ranging from 30 sec to 2 min is highly estimated as a vehicle stopping state other than that for waiting for a signal light (blue) or a chance for right-turning, that is, as a vehicle stopping state in which the headlamp is not required to be left turned on. As a result, just as in this embodiment, by allowing the headlamp to be left turned on until the non-ignition state is continued for more than a predetermined time (for example, 3.5 min), it is possible to leave the headlamp turned on in the vehicle stopping state for waiting for a signal light (blue) or a chance for right-turning, and also to suppress the wasteful power consumption of the battery because the headlamp is automatically turned off when the vehicle stopping time exceeds 3.5 min.
[0071]
The state in which the driver non-sitting state is detected after stopping of the vehicle is also highly estimated as a vehicle stopping state other than that for waiting for a signal light (blue) or a chance for right-turning. On the basis of the experience, however, it is

highly estimated that a driver temporarily stands up while straddling the vehicle directly after stoppage of the vehicle at an intersection, and therefore, it may be undesirable to automatically turn off the headlamp simultaneously with detection of the driver non-sitting state. For this reason, in this embodiment, the control system is configured such that the non-sitting time in the non-ignition state is counted, and the headlamp is automatically turned off if the above non-sitting time exceeds a predetermined time (3 sec in this embodiment) estimated as an elapsed time after a driver goes apart from the vehicle. [0072]
In addition, when the throttle is opened in the vehicle-stopping state in the "engine - stopping/vehicle-moving mode", the output from the AND circuit 807 indicates the "H" level and the flip-flop 810 is set, and consequently the headlamp is automatically turned on. [0073]
An AND circuit 813 of the headlamp control unit 800 outputs, to a buzzer drive unit 814, a logical product of the output signal S8012 from a non-sitting continuation discriminating unit 801, the output signal S9023 from a non-ignition continuation discriminating unit 802, and

the operational mode signal S301. The AND circuit 815 outputs, to the buzzer drive unit 814, a logical product of the output signal S8022 from the non-ignition continuation discriminating unit 802, the operational mode signal S301, and the signal indicating the state of the headlamp switch 57.
[0074]
When the output signal from the AND circuit 813 indicates the "H" level, that is, when the non-sitting in the non-ignition state in the "engine - stopping/vehicle-moving mode" is continued for a time-out period (1 sec in this embodiment) of a timer 8012 or more, the buzzer drive unit 814 outputs a buzzer drive signal for repeatedly generating alarm sound at a cycle of ON-time (0.2 sec)/OFF-time (1.5 sec). At this time, the output of the buzzer drive signal is continued until the main switch 73 is turned off or the driver rides again on the vehicle.
[0075]
When the output signal from the AND circuit 815 indicates the "H" level, that is, the headlamp switch 57 is in the ON state in the "engine-stopping/vehicle-moving mode" and also the non-ignition state is continued for a time-out period (3 min in this embodiment) of the timer

8022, the buzzer drive unit 814 outputs the same buzzer drive signal until the timer 8141 counts a predetermined time-out period. With this configuration, the operation for stopping the buzzer becomes unnecessary.
[0076]
In this embodiment, if the non-sitting state continued for 1 sec or more with the main switch left turned on is detected when the engine is
automatically stopped, it is discriminated that the driver goes away from the vehicle without turn-off of the main switch, with a result that the buzzer 75 is actuated. Accordingly, the driver can recognize the fact that the main switch is left turned-on.
[0077]
In this embodiment, the buzzer 75 is actuated before the headlamp automatic turn-off condition upon vehicle stopping state (the non-ignition state is continued for 3.5 sec or more) is established, for example, after the non-ignition state is continued for 3 min or more, so that the driver can previously recognize the automatic turn-off of the headlamp. That is to say, it is possible to prevent the headlamp from being automatically turned off without recognition of the driver.

[0078]
In the above embodiment, the configuration has been described that when it is detected that the non-sitting state is continued for 1 sec or more with the main power source left turned on after the engine is automatically stopped, the buzzer is continuously actuated until the main switch 73 is turned off or the driver rides again on the vehicle; however, in the case where it is supposed that the driver goes away from the vehicle without cut¬off of the main switch 73, for example, in the case where the vehicle is used for delivery service or bill collection service, the buzzer may be automatically stopped after an elapse of a predetermined time.
[0079]
Further, in the above embodiment, the configuration has been described that the headlamp is automatically turned off when the ignition-off state or the non-sitting state of the driver is continued for a predetermined time or more; however, the light of the headlamp may be weakened by reducing the supplied current in place of turn-off of the headlamp, or the headlamp may be turned off and instead a position lamp may be turned on.
[0080]
Fig. 9 is a block diagram showing the entire
configuration of an engine starting/stopping control system according to another embodiment of the present invention, in which the same symbols as those described above designate the same or similar parts.
In this embodiment, a power generated by the AC generator 72 is charged in two batteries 68A and 68B via the regulator/rectifier 67. The battery 68A, which is specialized for starting an engine, supplies a drive current to the starter motor 71 if a starter relay 62 is made conductive. The battery 68B supplies load currents via the main switch 73 to the various electrical equipment 74, the main control unit 60 and the like. [0081]
In this way, since the battery 68A specialized for starting the engine is very small in power consumption and is usually kept in a full-charge state, it is possible to usually desirably start the engine irrespective of the charged amount of the battery 68B. [0082]
Fig. 10 is a block diagram showing the configuration of an essential portion of the generator/motor 250 functioning as an engine assistor serving as engine starter which is one embodiment of the present invention. In this figure, the same symbols as

described above designate the same or similar parts. [0083]
A motor M of the generator/motor 250 has a rotor (not shown) connected to a crank shaft 201 of an engine 200. The rotational angle of the crank shaft 201 is detected by an angle sensor 49 and is supplied to a main control unit 60. The motor M includes, as described above, a generating coil 272 and a starting coil' 273 as stator coils; however, the operation in the case of using the starting coil 273 as the stator coil will be described in this embodiment.
[0084]
A brush type energization control means 902 receives the rotational motion of the crank shaft 201 and mechanically switches the contact between each stator coil (starting coil 273) of the motor M and a power supply line LI by means of brushes in accordance with the rotational angle of the crank shaft 201. As described in detail with reference to Fig. 5, the contact between each stator coil of the motor M and the power supply line is held upon starting of the engine and is released not upon starting of the engine by a governor mechanism 230. A brushless type energization control means 901 electrically switches the connection between each stator

coil of the motor M and the power supply line LI in response to a control signal supplied from the main control unit 60.
[0085]
The main control unit 60 has a generation control unit 601 adapted to control the brushless type energization control means 901 for allowing the motor M to function as the generator, and an assist control unit 602 adapted to control the brushless type energization control means 901 for allowing the motor M to function as the engine assistor.
[0086]
When the engine 200 requires a torque assist, the assist control unit 602 controls the brushless type energization control means 901 in response to the rotational angle of the crank shaft 201 for carrying out the torque assist of the engine 200. At this time, the assist control unit 602 selects the stator coil to be excited, of the motor M on the basis of the rotational angle of the crank shaft 201 detected by the angle sensor 49, and determines the energization time thereof on the basis of the throttle opening detected by a throttle sensor 50. The brushless type energization control means 901 supplies an exciting current from a battery 68 to the

stator coil selected by the assist control unit 602 for
the determined energization time.
[0087]
Fig. 11 is a diagram showing the circuit
configuration of one embodiment using a single-phase/six-pole motor as the motor M. In this figure, the same symbols as described above designate the same or similar parts. [0088]
In a brushless type energization control means 901A, six pairs of power FETs, in each pair of which two power FETs are connected in series, are connected in parallel. The common connection portions of the FET pairs are respectively connected to one-ends of stator coils LI to L6 and commutator segments 267 of a commutator holder 265. An annular positive commutator segment 298 of the commutator holder 265 is connected to a positive electrode of the battery 68 via a starter relay 62, and an annular negative commutator segment 299 is directly connected to a negative electrode of the battery 68.
[0089]
With this configuration, if the rotational number of the engine, that is, the rotational number of the crank shaft 201 is low, as described above, a brush

holder 262 is pushed on the commutator holder 265 side by the governor mechanism 230, so that the commutator segment 267 on one end side of the stator coil selected in accordance with the rotational angle of the crank shaft 201 and the commutator segment 267 on the other end side of the stator coil are sequentially connected to the positive commutator segment 298 and the negative commutator segment 299 by brushes 261 of the brush holder 262. Accordingly, the motor M functions substantially as a brush motor. [0090]
On the other hand, if the rotational number of the crank shaft 201 becomes high after termination of the starting of the engine, the brush holder 262 is separated from the commutator holder 265. In such a state, if the assist control begins by the assist control unit 602 of the main control unit 60, each FET of the brushless type energization control means 901A is subjected to chopping control based on a duty ratio corresponding to the throttle opening detected by the throttle sensor 50 so that an exciting current is selectively supplied from the battery 68 to the stator coil selected in accordance with the rotational angle of the crank shaft 201 detected by the angle sensor 49. It should be noted that the inverter

action by the brushless type energization control means 901A for the single-phase/six-pole motor is known and therefore the description thereof is omitted. [0091]
In this embodiment, since the current is supplied to the stator coil by the brush mechanism at a timing for controlling a relatively large exciting current, for example, upon starting of the engine, it is not required to increase the capacities of the FETs of the brushless type energization control means 901A. Further, since the current is supplied to the stator coil by the power FETs of the brushless type energization control means 901A at a timing for controlling a relatively small exciting
V
current, for example, upon engine assist, that is, the brush mechanism can be kept in a non-contact state, it is possible to prevent occurrence of wear and deterioration of the brushes 261.
[0092]
Incidentally, a general brushless motor requires a high accurate angle sensor because the absolute angle must be detected upon starting of the brushless motor. In this embodiment, however, when the motor is started as the brushless motor, the rotor of the motor has been already rotated, and accordingly, the rotor does not

require accurate angle detection, that is, it does not require a high accurate angle sensor. That is to say, it is sufficient for the motor functioning as the brushless motor in this embodiment to be provided with an inexpensive angle sensor with a simple structure.
[0093]
Fig. 12 is a diagram showing the circuit configuration of another embodiment using a three-phase motor as the motor M. In this figure, the same symbols as described above designate the same or similar parts.
[0094]
In a brushless type energization control means 901B, three pairs of power FETs, in each pair of which two power FETs are connected in series, are connected in parallel. The common connection portions of the FET pairs are connected to one-ends of stator coils LI to L3 and commutator segments 267 of a commutator holder 265, respectively. An annular positive commutator segment 298 is connected to a positive electrode of a battery 68 via a starter relay 62, and an annular negative commutator segment 299 is directly connected to a negative electrode of the battery 68.
[0095]
With this configuration, if the rotational number

of the engine, that is, the rotational number of the crank shaft 201 is low, as described above, a brush holder 262 is pushed on the commutator holder 265 side by a governor mechanism 230, so that the commutator segment 267 on one end side of the stator coil selected on the basis of the rotational angle of the crank shaft 201 and the commutator segment 267 on the other end side of the stator coil are sequentially connected to the positive commutator segment 298 and the negative commutator segment 299 by brushes 261 of a brush holder 262.
[0096]
On the other hand, if the rotational number of the crank shaft 201 becomes high, the brush holder 262 is separated from the commutator holder 265. In such a state, each FET of the brushless type energization control means 901B is subjected to chopping control based on a duty ratio corresponding to the throttle opening so that an exciting current is supplied from the battery 68 to the specified stator coil in accordance with the detected rotational angle of the crank shaft 201. It should be noted that the inverter action by the brushless type energization control means 901B for the three-phase motor is also known and therefore the description thereof is omitted.

[0097]
In this embodiment, since the current is supplied
to the stator coil by the brush mechanism at a timing for controlling a relatively large exciting current, for example, upon starting of the engine, it is not required to increase the capacities of the FETs of the brushless type energization control means 901B. Further, since the current is supplied to the stator coil b£ the power FETs of the brushless type energization control means 901B at a timing for controlling a relatively small exciting current, for example, upon engine assist, that is, the brush mechanism can be kept in a non-contact state, it is possible to prevent occurrence of wear and deterioration of the brushes 261.
[0098]
In this embodiment, the generator/motor 250 includes the generating coil 272 and the starting coil 273 as the stator coils, wherein the function as the starter motor 71 can be achieved by the brush motor using the starting coil 273 as the stator coil, the function as the assist motor 70 can be achieved by the brushless motor using the starting coil 273 as the stator coil, and the function as the ACG 72 can be achieved by the brushless motor using the generating coil 272 as the
stator coil. [0099]
However, if the main control unit 60 controls the switching timing of each FET of the brushless type energizatin control means 901B to allow the starting coil 273 to function as the generating coil during running of the vehicle in which the generator/motor 250 does not function as the assist motor 70, the generating coil 272 can be omitted. At this time, the main control unit 60 detects a terminal voltage of the battery 68 by a suitable means, and controls the duty ratio of a pulse signal for chopping control of each FET in such a manner that the output voltage from the generator/motor 250 exceeds the terminal voltage of the battery 68 by a specific value. [0100]
The assist control by the assist control unit 602 will be described with reference to Fig. 13.
[0101]
As described above, in the vehicle on which the engine stopping/starting control unit is mounted, when the driver opens the throttle grip at a time to, the generator/motor 250 functions as the starter motor to start the engine. After that, as the rotational number Ne

of the engine increases up to a rotational number Nin for clutch engagement at a time t2, the vehicle moves and at the same time the assist control unit 602 starts the control of the brushless type energization control means 901 to start the engine assist by the generator/motor 250. As a result, the drive wheel receives a total torque (TE + TM) of a torque TE generated by the engine and a torque TM generated by the generator/motor 250.'
[0102]
As the rotational number of the engine further increases, the engine can generate a sufficient torque, and accordingly, in this embodiment, the assist amount by the generator/motor 250 is gradually decreased with the increased rotational number of the engine, and the assist control is terminated when the rotational number of the engine reaches a predetermined reference rotational number Nref.
[0103]
As described above, in this embodiment, since the torque assist is performed until the rotational number of the engine reaches the reference rotational number Nref at which the engine can generate a sufficient torque after clutch engagement, it is possible to improve the movement feeling in combination with energy-saving.

[0104]
In the above embodiment, description is made by example of the vehicle including the engine stopping/starting control function; however, the present invention can be applied to a related art vehicle including no engine stopping/starting control function. In this case, as shown in Fig. 14, it may be desirable to perform the assist control after the rotational number of the engine reaches the rotational number Nin for clutch engagement. [0105]
Fig. 15 is a diagram showing a target assist torque Ttag generated by the generator/motor 250 with a throttle opening  th and a rotational number Ne of the engine taken as parameters. The target torque Ttag is set to be increased with the throttle opening  th.
[0106]
The torque TM generated by the generator/motor 250 is dependent on the duty ratio of a pulse signal for switching control of each FET of the brushless type energization control means 901. Accordingly, by controlling the duty ratio of a pulse signal for switching control of each FET as a function of the throttle opening  th and the rotational number Ne of the

engine in place of the above target torque, it is possible to obtain a desired engine assist.
[0107]
[Effect of the Invention]
According to the present invention, since the current is supplied to a stator coil by a brush mechanism at a timing for controlling a relatively large exciting current, for example, upon starting of the engine, it is not required to increase the capacities of power FETs for switching. Further, since the current is supplied to a stator coil by the power FETs for switching at a timing for controlling a relatively small exciting current, for example, upon engine assist, that is, the brush mechanism can be kept in the non-contact state, it is possible to prevent occurrence of wear and deterioration of brushes.
[Explanation of Symbols]
2: body front, 3: body rear, 4: floor portion, 6: down tube, 7: main pipe, 8: seat, 11: handlebar, 12: front fork, 13: front wheel, 15: bracket, 16: link member, 17: swing unit, 18: hanger bracket, 21: rear wheel, 22: rear cushion, 23: intake pipe, 24: carburetor, 25: air cleaner, 26: main stand, 27: kick shaft, 28: kick arm, 29: kick pedal, 200: engine, 201: crank shaft, 202: crank case, 203: cylinder block, 204: cylinder head,
206: ignition plug, 210: belt drive pulley, 211: boss, 212: V-belt, 250: generator/motor, 251: inner rotor, 300: operational mode switching unit, 400: starter relay control unit, 500: by-starter control unit, 600: indicator control unit, 700: ignition control unit, 800: headlamp control unit

WE CLAIM:
1. An engine assistor serving as an engine starter, including a motor (M) having a rotor (251) connected to a crank shaft (201) of an engine (200) and a stator (270) having multi-phase windings and which performs both engine starting and engine torque assist by said motor (M), comprising:
a rotational angle detector (49) for detecting a rotational angle of said crank shaft (201) and generating an angle signal;
a brushless type energization controller (901) for electrically switching the connection between each stator coil (273) of said motor (M) and a power supply line (L1) on the basis of the angle signal detected by said rotational angle detector (49);
a brush type energization controller (902) for receiving the rotational motion of said crank shaft (201) and mechanically switching the contact between each stator coil (273) and the power supply line (L1)
by means of brushes in accordance with the rotational angle of said
crank shaft (201); and
an assist controller (602) for biasing said brushless type energization controller (901) to drive said motor (M);
wherein said brush type energization controller (902) holds the contact between each stator coil (273) and the power supply line (L1) upon engine starting and releases the contact between each stator coil (273) and the power supply line (L1) not upon engine starting.
2. An engine assistor serving an engine starter as claimed in claim 1, wherein said brush type energization controller (902) comprises:
a commutator holder (265) for holding commutator segments (267) which are connected to respective stator coil (273) and the power supply line (L1) and which are arranged around said crank shaft (201), said commutator holder (265) being rotatable in synchronization with said crank shaft (201);
a brush holder (262) for holding brushes (261) arranged around said crank shaft (201), said brushes (261) being adapted to connect said commutator segment (267) of said stator coil (273) selected in accordance with the rotational angle of said crank shaft (201) to said commutator segment (267) of the power supply line (L1); and
a governor mechanism (230) for bringing said commutator segments (267) of said commutator holder (265) in contact with said brushes (261) of said brush holder (262) by an elastic force during a period in which said crank shaft (201) is rotated at a speed less than a specific value, and separating said commutator segments (267) from said brushes (261) against the elastic force when said crank shaft (201) is rotated at a speed equal to or more than the specific value.
3. An engine assistor serving as an engine starter as claimed in claim
1 or 2, wherein said brushless type energization controller (901) is
adapted to be biased by a power generation controller (610) so as to allow
said motor (250) to function as a generator.
4. An engine assistor serving as an engine starter as claimed in claim
1, for use in a vehicle having a belt type continuously variable
transmission and a centrifugal clutch.
5. An engine assistor serving as an engine starter substantially as herein described with reference to the accompanying drawings.

Documents:

558-del-1999-abstract.pdf

558-del-1999-claims.pdf

558-del-1999-correspondence-others.pdf

558-del-1999-correspondence-po.pdf

558-del-1999-description (complete).pdf

558-DEL-1999-Description Complete.pdf

558-del-1999-drawings.pdf

558-del-1999-form-1.pdf

558-del-1999-form-13.pdf

558-del-1999-form-19.pdf

558-del-1999-form-2.pdf

558-del-1999-form-3.pdf

558-del-1999-form-4.pdf

558-del-1999-form-6.pdf

558-del-1999-gpa.pdf

558-del-1999-petition-138.pdf

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Patent Number

220149

Indian Patent Application Number

558/DEL/1999

PG Journal Number

30/2008

Publication Date

25-Jul-2008

Grant Date

15-May-2008

Date of Filing

12-Apr-1999

Name of Patentee

HONDA GIKEN KOGYO KABUSHIKI KAISHA

Applicant Address

Inventors:

#	Inventor's Name	Inventor's Address
1	SATOSHI HONDA
2	SHOJI MOTODATE
3	MASAYUKI TORIYAMA

PCT International Classification Number

F02N 011/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	10-193734	1998-06-24	Japan