Title of Invention

A HYBRID MOTORCYCLE HAVING AN AUTOMATIC CENTRIFUGAL CLUTCH AND RUN BY POWER FROM ENGINE AND AUXILIARY POWER FROM MOTOR

Abstract

An automatic centrifugal clutch 16 is interposed in a power transmission system between an engine 12 and a driving wheel. A motor 13, which has a function to generate electricity and also is supplied with electricity from a battery 23 to generate auxiliary power, is connected to a crankshaft 36 of the engine 12. An acceleration data acquisition means is provided for acquiring the accelerator operation amount and the accelerator operation speed. A rotational speed detection means is provided for detecting the speed of the crankshaft 36. A rotational speed estimation means is provided for estimating the engagement completion rotational speed, which is a rotational speed at which the automatic centrifugal clutch 16 is completely engaged, according to the acceleration data acquired by the acceleration data acquisition means. A motor control means is provided for supplying the motor 13 with a magnitude of electricity in accordance with the acceleration data when the rotational speed detected by the rotational speed detection means has reached the engagement completion rotational speed estimated by the rotational speed estimation means.

Full Text

HYBRID MOTORCYCLE BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid motorcycle run by power from an engine and auxiliary power from a motor. 2. Description of the Related Art A conventional hybrid vehicle run by power from an engine and auxiliary power from a motor is disclosed in, for example, JP-A-2000-287306. The motor of the vehicle disclosed in JP-A-2000-287306 is connected to a crankshaft of the engine, and the operation of the motor is controlled by a control device. The auxiliary power from the motor and the power from the engine are added at the crankshaft, and transmitted to a driving wheel as a resultant force. A power transmission system between the engine and the driving wheel includes a manually operable clutch. The vehicle disclosed in JP-A-2000-287306 is run primarily by the power from the engine, to which the power from the motor is added, when the vehicle starts running, in order to increase the driving force. The control device for controlling the operation of the motor rotates the motor to generate a predetermined torque when predetermined starting conditions are satisfied. One of the starting conditions for this vehicle is that the clutch mentioned above is engaged. 1 This vehicle uses a clutch switch to detect whether or not the clutch is engaged. In general, in vehicles such as automobiles, a clutch is disengaged when the operator presses a clutch pedal, and the clutch switch detects displacement of the clutch pedal, or a detection element integrated with the clutch pedal. The present inventors thought of providing a scooter-type hybrid motorcycle utilizing the conventional technique for hybrid vehicles described above. However, the scooter-type motorcycle is provided with an automatic centrifugal clutch, rather than a manually operable clutch, in the power transmission system between the engine and the rear wheel, and thus it has not been easy to realize a scooter-type hybrid motorcycle. Different from the engine, the motor generates a large torque at relatively low speed. Thus, if the clutch is not completely engaged when applying auxiliary power from the motor when the motorcycle starts running, transmission of this large torque causes friction members in the clutch to slip, which makes it impossible for the motorcycle to start running. That is, if it is not possible to accurately detect the timing at which the automatic centrifugal clutch is completely engaged, that would be a problem in realizing a scooter-type hybrid motorcycle. The clutch switch used in JP-A-2000-287306 mentioned above 2 merely detects displacement of a manually operable member, and thus cannot detect the timing when the automatic centrifugal clutch is completely engaged. Even if the clutch switch could detect the engagement completion timing of the automatic centrifugal clutch, providing such a clutch switch would increase the cost, and if the clutch switch broke down, auxiliary power could not even be generated. SUMMARY OF THE INVENTION The present invention has been made to solve the foregoing problems, and therefore has an object to provide a hybrid motorcycle with excellent start and acceleration performance, in spite of including an automatic centrifugal clutch. In order to solve the above problems, a first aspect of the present invention provides a hybrid motorcycle having an automatic centrifugal clutch interposed in a power transmission system between an engine and a driving wheel, and a motor for auxiliary power connected to a crankshaft of the engine, the motor having a power generation function and also being supplied with electricity from a battery to rotate, the hybrid motorcycle including: an acceleration data acquisition means for acquiring as acceleration data at least an accelerator operation amount of an accelerator operating element, of accelerator operation amount and accelerator operation speed thereof; a rotational speed detection means for detecting a rotational speed of the 3 crankshaft or a rotary body for rotation in sync with the crankshaft; a rotational speed estimation means for estimating an engagement completion rotational speed, which is a rotational speed at which the automatic centrifugal clutch is completely engaged, according to the acceleration data acquired by the acceleration data acquisition means; and a motor control means for supplying the motor with a magnitude of electricity in accordance with the acceleration data when the rotational speed detected by the rotational speed detection means has reached the engagement completion rotational speed estimated by the rotational speed estimation means. The invention of a second aspect provides the hybrid motorcycle further including: an electricity supply restriction means for continuing supply of electricity to the motor for a predetermined electricity supply time and discontinuing the supply of electricity to the motor after the electricity supply time has elapsed. The invention of a third aspect provides the hybrid motorcycle further including: a charge level detection means for detecting a charge level of the battery, in which the electricity supply restriction means shortens the electricity supply time as the charge level detected by the charge level detection means becomes lower. The invention of a fourth aspect provides the hybrid motorcycle further including: a charging means for causing the 4 motor to generate electricity after the electricity supply time has elapsed and charging the battery with the generated electricity. The invention of a fifth aspect provides the hybrid motorcycle, in which the acceleration data acquisition means acquires the accelerator operation amount and the accelerator operation speed as the acceleration data, and the rotational speed estimation means estimates the engagement completion rotational speed based on a higher one of a first rotational speed and a second rotational speed, the first rotational speed being obtained based on the accelerator operation amount acquired by the acceleration data acquisition means, and the second rotational speed being obtained based on the accelerator operation speed acquired by the acceleration data acquisition means. The invention of a sixth aspect provides the hybrid motorcycle, in which the motor control means includes a prerotation means for rotating the motor in conjunction with rotation of the engine after an engine start and in an operating state in which power from the motor is not applied to the crankshaft. The invention of a seventh aspect provides the hybrid motorcycle, in which a rotation start timing, at which the prerotation means rotates the motor in conjunction with rotation of the engine, is set to a timing after an engine start 5 and when an engine speed is lower than an idling speed. The invention of an eighth aspect provides the hybrid motorcycle further including: a charge level determination means for determining whether or not the charge level of the battery is lower than a predetermined minimum charge level; and a precharging means for causing the motor to generate electricity and charging the battery with the generated electricity after an engine start and in an operating state in which power from the motor is not applied to the crankshaft, if the charge level determination means determines that the charge level of the battery is lower than the minimum charge level. The rotational speed of the rotary body when the automatic centrifugal clutch is completely engaged (engagement completion rotational speed) changes according to the accelerator operation amount (magnitude of the output torque from the engine) . That is, as the accelerator operation amount becomes larger, the output torque from the engine becomes larger and hence the engagement completion rotational speed becomes higher. According to the present invention, the engagement completion rotational speed is estimated by the rotational speed estimation means according to the acceleration data (operation amount of the accelerator operating element, accelerator operation speed). The motor is supplied with 6 electricity to generate power when the rotational speed of the rotary body is increased with the accelerator operation and has reached the engagement completion rotational speed. Therefore, according to the present invention, the auxiliary power from the motor can be applied to the automatic centrifugal clutch with the clutch completely engaged. Thus, the power from the engine and the auxiliary power from the motor can be efficiently transmitted via the automatic centrifugal clutch to the driving wheel. As a result, the present invention can provide a hybrid motorcycle with excellent start and acceleration performance. An existing sensor for use to control the rotation of the engine can be used to detect the operation amount and the operation speed of the accelerator operating element. Thus, it is not necessary to provide a new member for detection purposes, such as sensor or switch, in order to implement the present invention. In this way, the present invention can be implemented while reducing the cost. The hybrid motorcycle 1 according to the present invention does not include a sensor or a switch exclusively for detecting the completion of engagement of the automatic centrifugal clutch. Thus, according to the hybrid motorcycle, the operation to apply auxiliary power can be performed with high reliability compared to the case where a dedicated sensor or switch is used to detect the completion of engagement of the 7 clutch. According to the second aspect the invention, the supply of electricity to the motor is discontinued after the vehicle starts running or accelerates. Thus, the consumption of electricity in the battery can be reduced compared to the case where the supply of electricity to the motor is continued after the vehicle starts running or accelerates. According to the third aspect of the invention, the charge level of the battery is not lowered excessively. Thus, it is possible to secure electricity for use to cause the motor to generate auxiliary power next time. According to the fourth aspect of the invention, the battery can be charged after electricity in the battery has been consumed. Thus, it is possible to secure sufficient electricity to be supplied to the motor 13 next time. According to the fifth aspect of the invention, the rotational speed estimation means can estimate the engagement completion rotational speed to be higher as the accelerator operation speed is higher, even if the accelerator operation amount is constant. Thus, the power from the motor can be applied to the automatic centrifugal clutch at an appropriate timing in accordance with the accelerator operation speed, even in the case of a motorcycle which is often caused to start running or accelerate with the accelerator fully open, such as motorcycle incorporating a small-displacement engine. 8 Therefore, according to the present invention, the power from the engine and the auxiliary power from the motor can be more reliably transmitted to the rear wheel. According to the sixth aspect of the invention, it is possible to prevent the motor, which is not driving to generate auxiliary power, from serving as a load on the engine, which can stabilize the rotation of the engine in an idling state. According to the seventh aspect of the invention, the motor is rotated after an engine start and before the engine speed reaches an idling speed, which reduces a load on the engine. Thus, the engine shifts to an idling state while rotating stably after an engine start, even if the motor is connected to the crankshaft. Therefore, the present invention can provide a hybrid motorcycle in which the series of operations, including starting the engine and the vehicle starting running and accelerating, can be performed smoothly. According to the eighth aspect of the invention, if the charge level of the battery is low, the battery can be charged when auxiliary power from the motor is not necessary, for example when the vehicle is at a halt. Thus, according to the present invention, the battery can be prevented from being over-discharged, and it is possible to secure electricity for use to cause the motor to generate auxiliary power next time. BRIEF DESCRIPTION OF DRAWINGS 9 FIG. 1 is a side view of a hybrid motorcycle according to the present invention; FIG. 2 is a horizontal cross sectional view of a power unit; FIG. 3 is a block diagram showing the configuration of a control system of the hybrid motorcycle according to the present invention; FIG. 4 is a block diagram showing the configuration of a motor/generator control section; FIG. 5 shows graphs for explaining how to set the engagement completion rotational speed; FIG. 6 is a graph showing the relation between the APS angle and the driving current for a motor; FIG. 7 is a graph showing the relation between the charge level of a battery and the electricity supply time to the motor; FIG. 8 is a graph as a map for obtaining the charge level of the battery based on the open circuit voltage of the battery; FIG. 9 is a graph as a map for obtaining the charge level of the battery based on the battery current and the battery voltage; FIG. 10 is a graph as a map for setting the charge current and the discharge current for a charge level of the battery; FIG. 11 is a flowchart for explaining the operation of the hybrid motorcycle according to the present invention; FIG. 12 is a flowchart for explaining the operation of a control device after an engine start until auxiliary power is 10 generated by the driving of the motor; FIG. 13 is a time chart for explaining the operation of the hybrid motorcycle according to the present invention; and FIG. 14 is a time chart for explaining the operation of the hybrid motorcycle according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A description will hereinafter be made of an embodiment of the hybrid motorcycle according to the present invention with reference to FIGs. 1 to 14. FIG. 1 is a side view of the hybrid motorcycle according to the present invention. FIG. 2 is a horizontal cross sectional view of a power unit. FIG. 3 is a block diagram showing the configuration of a control system of the hybrid motorcycle according to the present invention. FIG. 4 is a block diagram showing the configuration of a motor/generator control section. FIG. 5 shows graphs for explaining how to estimate the engagement completion rotational speed, in which FIG. 5 (A) is a graph as a map for obtaining a first rotational speed based on the APS angle, FIG. 5(B) is a graph as a map for obtaining a second rotational speed based on the APS change rate, and FIG. 5 (C) is a graph showing changes in actual engagement completion rotational speed based on the first rotational speed and the second rotational speed. 11 FIG. 6 is a graph showing the relation between the APS angle and the driving current for a motor. FIG. 7 is a graph showing the relation between the charge level of a battery and the electricity supply time to the motor. FIG. 8 is a graph as a map for obtaining the charge level of the battery based on the open circuit voltage of the battery. FIG. 9 is a graph as a map for obtaining the charge level of the battery based on the battery current and the battery voltage. FIG. 10 is a graph as a map for setting the charge current and the discharge current for a charge level of the battery. FIG. 11 is a flowchart for explaining the operation of the hybrid motorcycle according to the present invention. FIG. 12 is a flowchart for explaining the operation of a control device after an engine start until the motor generates auxiliary power. FIGs. 13 and 14 are each a time chart for explaining the operation of the hybrid motorcycle according to the present invention. FIG. 13 corresponds to the case where an accelerator is operated such that the accelerator operation amount increases generally in proportion to the time from start to end of the operation. FIG. 14 corresponds to the case where the accelerator is once reversed slightly at the middle of the starting operation and then the starting operation is performed again. In the drawings, reference numeral 1 denotes a hybrid motorcycle according to this embodiment. Reference numeral 2 denotes a front wheel of the motorcycle 1, 3a front fork, 4 12 steering handlebars, 5 a rear wheel as the driving wheel, 6 a power unit for driving the rear wheel 5, 7 a seat, and 8 a body cover. The front wheel 2 can be steered to the left and right by rotationally moving the steering handlebars 4. An accelerator grip 9 for increasing and decreasing the driving force of the power unit 6 and a front wheel brake lever (not shown) are provided at an end of the steering handlebars 4 on the right side of the vehicle body. The accelerator grip 9 constitutes the accelerator operating element of the present invention. As shown in FIG. 2, the accelerator grip 9 is supported for free rotational movement on the steering handlebars 4, although not shown. The accelerator grip 9 is provided with an accelerator operation amount detector 11 (hereinafter simply referred to as "APS" (accelerator position sensor)) for detecting the operation amount (rotational angle relative to the handlebars) of the accelerator grip 9. The rear wheel 5 is supported for free rotation at the rear end of the power unit 6 to be discussed later, in order to be rotated by the power from an engine 12 and the auxiliary power from a motor 13 provided in the power unit 6. The power unit 6 is a unit swing type, and supported for free vertical swinging movement on a body frame by a link mechanism (not shown) coupled to the front end. As shown in FIG. 1, a cushion unit 14 is interposed between the rear end 13 of the power unit 6 and the body frame (not shown). As shown in FIG. 2, the power unit 6 is made up of an engine 12 and a motor 13 provided at its end on the front side of the vehicle (on the right side in FIG. 2) , a belt-type continuously variable transmission 15 (hereinafter simply referred to as "CVT") extending longitudinally on the left side of the vehicle body, an automatic centrifugal clutch 16 provided at the rear end of the CVT 15, a gear-type speed reducer 18 provided between the automatic centrifugal clutch 16 and an axle 17 of the rear wheel 5, a control device 19 (see FIG. 3) for controlling the operation of the engine 12 and the motor 13, etc. A main switch 21, a start switch 22, a battery 23, etc., are connected to the control device 19. The start switch 22 is intended to start the engine 12, and in this embodiment uses the motor 13 to start the engine 12. At the time of starting, the motor 13 substantially functions as a starter motor. Alternatively, a dedicated starter motor may be used to start the engine 12, as in the case with common conventional motorcycles. The engine 12 is a 4-cycle engine including a crankcase 31 shown in FIG. 2, and a cylinder (not shown) provided in front of the crankcase 31 and extending upward. An intake system having a throttle valve 32 (see FIG. 3) and an exhaust system having a muffler 33 (see FIG. 1) are connected to the cylinder. The throttle valve 32 is connected to the accelerator grip 14 9 via a wire (not shown) , and opens and closes through operation of the accelerator grip 9. The throttle valve 32 is provided with a throttle valve opening sensor (not shown) for detecting the opening of the throttle valve 32. The throttle valve opening sensor is connected to an engine control section 34 of the control device 19 shown in FIG. 3 and to be discussed later, and sends to the engine control section 34 the opening of the throttle valve 32 as detected data. The engine 12 is arranged in such that the fuel injector 35 (see FIG. 3) injects fuel into an intake passage. The fuel injection amount from the fuel injector 35 is set by the engine control section 34 according to the opening of the throttle valve 32 and the speed of the engine 12. The speed of the engine 12 is calculated utilizing the number of ignition pulses generated by an ignition system having an ignition plug (not shown). The ignition timing of the engine 12 is set by the engine control section 34 based on the rotational angle of the crankshaft 36. The rotational angle of the crankshaft 36 is detected by an electromagnetic pickup 37 (see FIG. 2) attached to the crankcase 31. The electromagnetic pickup 37 is positioned to face a tooth 38a provided to a rotor 38 (see FIG. 2) of the motor 13 to be discussed later, and sends a detection signal to the engine control section 34 when it has detected the tooth 38a magnetically. 15 As shown in FIG. 2, the crankshaft 36 of the engine 12 is supported on the crankcase 31 by bearings 39, 40 for free rotation. The crankcase 31 is made up of a left half 41 and a right half 42. The left half 41 is formed integrally with a longitudinally extending portion 41a extending longitudinally on the left side of the rear wheel 5, to which a transmission case cover 43 is attached. The left half 41 of the crankcase 31 and the transmission case cover 43 constitute a transmission case 44 housing and also supporting the CVT 15, the automatic centrifugal clutch 16, the gear-type speed reducer 18, etc. A motor housing 45 for the motor 13 to be discussed later is attached to the right half 42 of the crankcase 31. As shown in FIG. 2, a driving pulley 4 6 of the CVT 15 is mounted to an end of the crankshaft 36 on the left side of the vehicle body. The driving pulley 4 6 is made up of a fixed sheave half 46a fixed to the crankshaft 36, a movable sheave half 46b supported on the crankshaft 36 so as to move freely axially thereof but not to rotate relative thereto, and a drive mechanism (not shown) for moving the movable sheave half 46b axially on the crankshaft 36. The CVT 15 is made up of the above driving pulley 46, a driven pulley 47 positioned on the rear side of the vehicle body, and a V-belt 48 wrapped around both the pulleys 46, 47. As conventionally well known, the CVT 15 continuously varies the 16 rotation of the crankshaft 36 for transmission to a rotary shaft 49 of the driven pulley 47. The driven pulley 47 is made up of a fixed sheave half 47a fixed to the rotary shaft 49, and a movable sheave half 47b supported on the rotary shaft 49 so as to be movable axially thereof and also be urged toward the fixed sheave half 47a by a compression coil spring (not shown) . The rotary shaft 4 9 is formed in the shape of a cylinder, and supported for free rotation through a bearing (not shown) on an intermediate shaft 50 passing through the hollow part of the rotary shaft 49. The intermediate shaft 50 is supported for free rotation on the transmission case 44 through bearings 51, 52. An input part 16a of the automatic centrifugal clutch 16 is connected to an end of the rotary shaft 4 9 on the left side of the vehicle body. The automatic centrifugal clutch 16 is made up of the above input part 16a having a clutch shoe 16b, and a clutch outer 16c housing the input part 16a. The clutch outer 16c is fixed to an end of the intermediate shaft 50 on the left side of the vehicle body. An end of the intermediate shaft 50 on the right side of the vehicle body is connected to the axle 17 of the rear wheel 5 via the gear-type speed reducer 18, which is a two-staged type. The axle 17 of the rear wheel 5 is supported for free rotation on the transmission case 44 through bearings 53, 54. With the thus constructed power unit 6, rotation of the 17 crankshaft 36 is transmitted from the driving pulley 46 via the V-belt 48 to the driven pulley 47 of the CVT 15, and then from the rotary shaft 4 9 to the input part 16a of the automatic centrifugal clutch 16. As the rotation of the crankshaft 36 increases, the rotation of the input part 16a increases. Then, a centrifugal force increases the diameter of the clutch shoe 16b, which causes the clutch shoe 16b to engage with the clutch outer 16c. This in turn causes the clutch outer 16c to rotate. This rotation is transmitted from the intermediate shaft 50 via the gear-type speed reducer 18 to the axle 17 (rear wheel 5) . As shown in FIG. 2, a rotor 38 of the motor 13 to be discussed later is mounted to an end of the crankshaft 36 on the right side of the vehicle body. The motor 13 is intended to apply auxiliary power to the crankshaft 36, and has a function to generate electricity by being driven by the engine 12. The motor 13 includes the above rotor 38 and a stator 61 fixed to the motor housing 45, and as shown in FIG. 3, is connected to a motor/generator control section 62 of the control device 19. The rotor 38 is made up of a boss 38b fixed to the crankshaft 36, a disk 38c extending radially from an end of the boss 38b on the left side of the vehicle body, a cylinder 38d housing the disk 38c, and a permanent magnet 63 secured to an end surface of the disk 38c on the right side of the vehicle body. The tooth 38a to be detected by the electromagnetic pickup 37 is formed 18 on the outer periphery of the cylinder 38d. The motor 13 directly drives the crankshaft 36. The stator 61 incorporates a coil 64, and is fixed to the motor housing 45 in such a manner as to be partially inserted into the cylinder 38d and face the permanent magnet 63. The stator 61 is provided on a circumference centered on the axis of the crankshaft 36. The stator 61 of the motor 13 also incorporates an encoder 65 (see FIG. 3) for detecting the speed of the rotor 38 (speed of the crankshaft 36). The motor/generator control section 62 is intended to control the timing for supplying the motor 13 with electricity and the magnitude of the electricity, and also switch the motor 13 to function as a generator. As shown in FIG. 4, the motor/generator control section 62 includes an acceleration data acquisition means 71, a rotational speed detection means 72, a rotational speed estimation means 73, a motor control means 74, a charge level detection means 75, a charging means 76, a charge level determination means 77, a precharging means 78 and a timer 79. The acceleration data acquisition means 71 acquires the accelerator operation amount (operation angle of the accelerator grip 9) detected by the APS 11 and the accelerator operation speed (speed at the time when the accelerator grip 9 is operated) as acceleration data. 19 The rotational speed detection means 72 detects the speed of the engine 12. According to this embodiment, the rotational speed detection means 72 is arranged to obtain the speed of the crankshaft 36 using the encoder 65. Instead of the speed of the crankshaft 36, the rotational speed detection means 72 may detect the speed of the rotor 38 of the motor 13. Also, the rotational speed detection means 72 may detect the rotational speed of a rotary body directly connected to the crankshaft 36, the rotor 38 or the like for rotation in sync therewith, or that of a rotary body (not shown) connected to the crankshaft 36, the rotor 38 or the like via a transmission means (not shown) such as gear or chain for rotation in sync therewith. To detect the speed of the rotor 38, the electromagnetic pickup 37 may be used. The rotational speed estimation means 73 estimates the speed of the engine 12 at which the motor 13 is caused to generate auxiliary power, in a manner to be described later. Here, estimation is made in such that the estimated rotational speed is the rotational speed at which the automatic centrifugal clutch is completely engaged (engagement completion rotational speed). For example, in the case where the accelerator grip 9 is operated greatly and rapidly, the power from the engine 12 to be applied to the automatic centrifugal clutch 16 becomes relatively large, which makes the rotational speed at which the 20 automatic centrifugal clutch 16 is completely engaged relatively high. Thus, the engagement completion rotational speed is estimated to be relatively high. In the case where the engagement completion rotational speed is not estimated and the motor 13 is supplied with electricity in conjunction with the accelerator operation, auxiliary power is generated by the driving of the motor 13 right at the start of the accelerator operation, and too large a torque is applied before the automatic centrifugal clutch 16 has been completely engaged. Thus, the clutch shoe 16b may slip to prevent the vehicle from starting running. The rotational speed estimation means 73 estimates the engagement completion rotational speed based on a higher one of a provisional rotational speed estimated based on the accelerator operation amount (hereinafter referred to as "first rotational speed") and a provisional rotational speed estimated based on the accelerator operation speed (hereinafter referred to as "second rotational speed"). Now, a detailed description will be made of how to estimate the engagement completion rotational speed. The rotational speed estimation means 73 according to this embodiment estimates the final engagement completion rotational speed using the maps shown in FIGs. 5 (A) to 5 (C) . FIG. 5 (A) is a graph as a map for obtaining a set value A, which is equivalent to the first rotational speed in accordance with the accelerator 21 operation amount. FIG. 5 (B) is a graph as a map for obtaining a set value B, which is equivalent to the second rotational speed in accordance with the accelerator operation speed. FIG. 5(C) is a graph as a map for estimating the final engagement completion rotational speed based on the set value A and the set value B. As shown in FIG. 5 (A) , the set value A is set in such that the rotational speed becomes higher as the accelerator operation amount becomes larger until the accelerator operation amount reaches a predetermined upper limit, and in such that the rotational speed maintains a constant maximum speed, even if the accelerator operation amount increases, after the accelerator operation amount has reached the upper limit. As shown in FIG. 5(B), the set value B is set in such that the rotational speed becomes higher as the accelerator operation speed becomes higher until the accelerator operation speed reaches a predetermined upper limit, and in such that the rotational speed maintains a constant maximum speed, even if the accelerator operation speed increases, after the accelerator operation speed has reached the upper limit. The rotational speed estimation means 73 reads a set value A in accordance with the accelerator operation amount acquired by the acceleration data acquisition means 71, from the map shown in FIG. 5 (A) . The rotational speed estimation means 73 also reads a set value B in accordance with the accelerator 22 operation speed acquired by the acceleration data acquisition means 71, from the map shown in FIG. 5 (B) . The rotational speed estimation means 73 then compares the set value A and the set value B, applies the larger one of the set values A, B to the map shown in FIG. 5 (C) , and reads the final engagement completion rotational speed as a set value from the drawing. The motor control means 74 includes an electricity supply restriction means 81 and a prerotation means 82 to be discussed later, and supplies the motor 13 with a magnitude of electricity in accordance with the accelerator operation amount after the accelerator grip 9 in an idling state is operated and the speed of the engine 12 has reached the engagement completion rotational speed. Whether or not the accelerator grip 9 is in an idling state is detected using the accelerator operation amount acquired by the acceleration data acquisition means 71. That is, the accelerator grip 9 is determined to be in an idling state if the accelerator operation amount is 0. Whether or not the accelerator grip 9 has been operated is detected by determining whether or not the accelerator operation amount has changed from 0. In supplying the motor 13 with a magnitude of electricity in accordance with the accelerator operation amount, the motor control means 74 reads a magnitude of driving current in accordance with the accelerator operation amount, from the map 23 shown in FIG. 6, and controls the voltage such that the magnitude of driving current flows through the motor 13. The motor control means 74 supplies the motor 13 with electricity only when the charge level of the battery 23 is above a minimum charge level to be discussed later. The electricity supply restriction means 81 restricts the length of time for the motor control means 74 to supply the motor 13 with electricity, to a predetermined electricity supply time. The electricity supply time is set by an electricity supply time setting means 83 to be discussed later. That is, the electricity supply restriction means 81 continues the supply of electricity to the motor 13 for the electricity supply time, and discontinues the supply of electricity to the motor 13 after the electricity supply time has elapsed. The electricity supply time is counted by the timer 79. The electricity supply time setting means 83 changes the electricity supply time according to the charge level of the battery 23 detected by the charge level detection means 75 to be discussed later. In changing the electricity supply time, the electricity supply time setting means 83 uses the map shown in FIG. 7. FIG. 7 is a graph showing the driving time for a charge level of the battery 23 (battery SOC). As shown in the graph, the electricity supply time is set to be shorter as the charge level of the battery 23 becomes lower. The electricity supply time setting means 83 reads an electricity supply time 24 in accordance with the present charge level of the battery 23, from the map shown in FIG. 7, and sends the electricity supply time to the electricity supply restriction means 81. That is, the electricity supply restriction means 81 shortens the electricity supply time as the charge level detected by the electricity supply time setting means 83 becomes lower. The prerotation means 82 is intended to prevent the motor 13 not generating auxiliary power from serving as a load on the engine 12, and arranged to start energization in order to rotate the motor 13 when the speed of the engine 12 has reached a predetermined prerotation speed. In this embodiment, the prerotation speed is set to be lower than the speed of the engine 12 in an idling state (idling speed). That is, in the hybrid motorcycle 1 according to this embodiment, the prerotation means 82 rotates the motor 13 in conjunction with the rotation of the engine 12 after an engine start and when the engine speed has reached the prerotation speed lower than the idling speed. The speed of the engine 12 is detected by the rotational speed detection means 72. The charge level detection means 75 obtains a charge level (SOC) of the battery 23 in accordance with the release voltage of the battery 23 using a map as the graph shown in FIG. 8, and then adds, to this charge level, the current amount while the battery 23 is charging and the current amount while the battery 23 is discharging to obtain the present charge level. The 25 battery release voltage is detected by the charge level detection means 75 while electricity in the battery 23 is not consumed or while the battery 23 is not charged, for example when the engine is stopped. The battery 23 is charged by the charging means 7 6 to be discussed later. The current while charging and the current while the battery 23 is discharging are measured by a current detector 84 (see FIG. 3) provided in the circuit connecting the battery 23 and the motor/generator control section 62. Instead of measuring and adding the charge current and the discharge current each time as discussed above, a map as shown in FIG. 9 may be used to detect the charge level of the battery 23 during engine operation. In the map shown in FIG. 9, the charge level (SOC) of the battery 23 is defined by the battery current and the battery voltage. The map shows the relation between the voltage between the terminals of the battery 23 and the current flowing through the battery 23 at each charge level from 0% to 100%. In the case of using this map to obtain the charge level of the battery 23, the charge level detection means 75 detects the present values of the current flowing through the battery 23 and the voltage between the terminals of the battery 23, and reads a charge level (SOC) in accordance with these current and voltage values from the map. The charging means 76 causes the motor 13 to function as a generator and to generate electricity after the above 26 electricity supply time has elapsed, and charges the battery 23 with the generated electricity. The charging means 76 also changes the amount of electricity to be generated according to the charge level detected by the charge level detection means 75. That is, the charging means 76 reduces the charge current when the charge level of the battery 23 is relatively high, and increases the charge current when the charge level of the battery 23 is relatively low. The charge level determination means 77 compares the charge level of the battery 23 detected by the charge level detection means 75 and the predetermined minimum charge level if auxiliary power is not generated by the driving of the motor 13. The charge level determination means 77 also sends a control signal to the prerotation means 82 to discontinue the supply of electricity to the motor 13, and sends a control signal to the precharging means 78 to be discussed later to start charging, when the charge level of the battery 23 is lower than the minimum charge level. On receiving the control signal, the prerotation means 82 stops the supply of electricity to the motor 13. When the control signal is sent from the charge level determination means 77, the precharging means 77 causes the motor 13 to function as a generator and to generate electricity if auxiliary power is not generated by the driving of the motor 13. The charge current while generating electricity is read from the map shown in FIG. 10 and set. The map shows the charge 27 current and the discharge current of the battery 23 for a charge level (SOC) of the battery 23. As can be understood from this map, the precharging means 78 according to this embodiment increases the charge current as the charge level of the battery 23 becomes lower when the charge level is between the minimum charge level Cl and a limit value C2 lower than that. Also, the precharging means 78 performs charging at a constant maximum charge current when the charge level is lower than the limit value C2. When the motor 13 is caused to function as a generator while the engine 12 in low-speed operation, the engine control section 34 of the hybrid motorcycle 1 increases the fuel injection amount from the injector 35 so as to stabilize the rotation of the engine 12. At this time, for example when the accelerator grip 9 is in an idling position, the fuel injection amount is controlled such that the engine speed reaches the idling speed during normal operation. When the accelerator operation amount is increased from the idling state, the engine control section 34 increases the fuel injection amount according to the increase in accelerator operation amount. Thus, since the fuel injection amount is increased according to an increase in load due to electricity generation by the motor 13, the engine 12 can be prevented from stalling because of such an increase in load due to electricity generation. Now, a description will be made of the operation of the 28 motor/generator control section 62 constructed as described above using the flowcharts shown in FIGs. 11 and 12 and the time chart shown in FIG. 13. The engine 12 is started by turning ON the main switch 21 and then turning ON the start switch 22 in steps Pi to P3 of the flowchart shown in FIG. 11. The timing of turning ON the main switch 21 is indicated as time Tl in FIG. 13, and the timing of turning ON the start switch 22 is indicated as time T2 in FIG. 13. After an engine start, the acceleration data acquisition means 71 acquires acceleration data (accelerator operation amount and accelerator operation speed) in step P4, and the charge level determination means 77 determines in step P5 whether or not the charge level of the battery 23 is lower than the minimum charge amount. If the charge level of the battery 23 is equal to minimum charge level or lower, the precharging means 7 8 reads a charge current for the motor 13 from the map shown in FIG. 10 in step P6, and causes the motor 13 to function as a generator and to generate electricity so as to obtain the charge current in step P7. Then, the process returns to step P4 to repeat the above processes. The timing at which electricity generation is started in step P7 is indicated as time T3 in FIG. 13. On the other hand, if it is determined in step P5 that the charge level of the battery 23 is higher than the minimum charge 29 level, the process proceeds to step P8, where the driving current for the motor 13 is set. Here, the operation performed in step P8 is described with reference to the flowchart shown in FIG. 12. First of all, the speed of the engine 12 is detected in step SI of the flowchart shown in FIG. 12, and energization is started to rotate the motor 13 when the engine speed has reached the prerotation speed as shown in steps S2 to S3. The prerotation speed is indicated as symbol R in FIG. 13. Also, the timing at which the motor 13 rotates in conjunction with the rotation of the engine 12 is indicated as time T4 in FIG. 13. Subsequently, acceleration data are acquired again in step S4, and it is determined in step S5 whether or not an accelerator operation has been performed. If an accelerator operation has not been performed, the process returns to step S1. If an accelerator operation has been performed, a set value A (first rotational speed) in accordance with the accelerator operation amount at that time is read from the map shown in FIG. 5 (A) in step S6, and a set value B (second rotational speed) in accordance with the accelerator operation speed at that time is read from the map shown in FIG. 5(B) in step S7. The timing at which the accelerator operation has been performed is indicated as time T5 in FIG. 13. Then, in step S8, based on the larger one of the set value 30 A and the set value B (the one that brings about a higher rotational speed), the final engagement completion rotational speed is read as a set value from the map shown in FIG. 5(C). After the engagement completion rotational speed is estimated in this way, it is determined in step S9 whether or not the speed of the engine 12 has reached the engagement completion rotational speed. If the speed of the engine 12 has not reached the engagement completion rotational speed, the process returns to step S4. After the speed of the engine 12 has reached the engagement completion rotational speed, the driving current for the motor 13 is read from the map shown in FIG. 6 in step S10, and the electricity supply time is read from the map shown in FIG. 7 in step Sll. The electricity supply time becomes shorter as the charge level of the battery 23 becomes lower. After preparations have been made to cause the motor 13 to generate auxiliary power, the driving current is passed to the motor 13 to generate auxiliary power by the driving of the motor 13 in step P9 of the flowchart shown in FIG. 11. The timing of generating auxiliary power is indicated as time T6 in FIG. 13. At this time, the timer 7 9 starts counting the time. At this time, the speed of the engine 12 has increased to the engagement completion rotational speed since the start of the accelerator operation (T5), and the automatic centrifugal clutch 16 has completely been engaged. Thus, the resultant 31 force of the power from the engine 12 and the auxiliary power from the motor 13 is transmitted from the automatic centrifugal clutch 16 via the gear-type speed reducer 18 and the axle 17 to the rear wheel 5. As a result, the acceleration at which this vehicle starts running is large compared to common motorcycles that run only on the power from the engine 12. Meanwhile, if the charge level of the battery 23 is lower than the minimum charge level, the electricity generation amount is increased from an electricity generation amount for idling L to an electricity generation amount for running H after the speed of the engine 12 has reached the engagement completion rotational speed, as shown in FIG. 13. After auxiliary power is generated by the driving of the motor 13 as discussed above, it is determined in step P10 whether or not the electricity supply time has elapsed from the start of the driving of the motor 13. If the electricity supply time has not elapsed, the process returns to step P9. If the electricity supply time has elapsed, the supply of electricity to the motor 13 is discontinued in step Pll. The timing of stopping the supply of electricity is indicated as time T7 in FIG. 13. After the supply of electricity to the motor 13 is discontinued, the motor 13 is caused to function as a generator and to generate electricity in steps P6, P7. The timing of 32 starting the generation of electricity is indicated as time T8 in FIG. 13. The amount of electricity generated at this time is also increased and decreased according to the charge level of the battery 23. Aside from when the vehicle starts running as discussed above, the motor 13 is also caused to generate auxiliary power for example when the accelerator grip 9 is returned to an idling position while the vehicle is running and then operated to increase the running speed from a coasting state. Thus, also at this time, the automatic centrifugal clutch 16 does not slip and high acceleration performance can be achieved by the auxiliary power by the driving of the motor 13. In the operation example shown in FIG. 13, the operation amount of the accelerator grip 9 is continuously increased from the start of the operation until the vehicle starts running. In the case where the accelerator is operated irregularly, an operation similar to the above example where only the engagement completion rotational speed is different is performed. For example, in the case where the accelerator grip 9 is once reversed slightly at the middle of the starting operation and then the starting operation is performed again, the operation as shown in FIG. 14 is performed. In FIG. 14, the timing of starting the reversing operation of the accelerator grip 9 at the middle of the starting operation is indicated as time T10, and the timing at which the accelerator 33 grip 9 is completely reversed and the starting operation is started again is indicated as time T11. As shown in FIG. 14, the estimated value, which represents the engagement completion rotational speed, is reduced by reversing the accelerator grip 9, and increased by operating the accelerator grip 9 again. Also in this case, the motor 13 is caused to generate auxiliary power when the speed of the engine 12 has reached the engagement completion rotational speed (T6) after the start of the accelerator operation (T5). In the hybrid motorcycle 1 constructed as described above, the auxiliary power from the motor 13 is applied to the automatic centrifugal clutch 16 with the automatic centrifugal clutch 16 completely engaged. Thus, the resultant force of the power from the engine 12 and the auxiliary power from the motor 13 can be efficiently transmitted from the automatic centrifugal clutch 16 to the rear wheel 5 side without any loss of power in the automatic centrifugal clutch 16. Therefore, according to this embodiment, a hybrid motorcycle 1 with excellent start and acceleration performance can be manufactured. Also, in this embodiment, an existing APS 11 for use to control the rotation of the engine 12 is used to detect the operation amount and the operation speed of the accelerator grip 9. Thus, it is not necessary to provide a new member for detection purposes, such as sensor or switch, in order to 34 manufacture the hybrid motorcycle 1, which contributes to cost reduction. In the hybrid motorcycle 1 according to this embodiment, a sensor or a switch for detecting the completion of engagement of the automatic centrifugal clutch 16 is not exclusively used. Thus, according to the hybrid motorcycle 1, the operation to apply auxiliary power can be performed with high reliability compared to the case where a dedicated sensor or switch is used to detect the completion of engagement of the automatic centrifugal clutch. In the hybrid motorcycle 1 according to this embodiment, the supply of electricity to the motor 13 is discontinued after the vehicle starts running or accelerates and when a predetermined electricity supply time has elapsed. Thus, the consumption of electricity in the battery 23 can be reduced compared to the case where the supply of electricity to the motor 13 is continued after the vehicle starts running or accelerates . In the hybrid motorcycle 1 according to this embodiment, the electricity supply time becomes shorter as the charge level of the battery 23 becomes lower. Thus, the charge level of the battery 23 is not lowered excessively. Therefore, according to the hybrid motorcycle 1, it is possible to secure electricity for use to cause the motor 13 to generate auxiliary power next time. In the hybrid motorcycle 1 according to this embodiment, 35 the motor 13 generates electricity after the electricity supply time has elapsed, and the battery 23 is charged with the generated electricity In this way, according to the hybrid motorcycle 1, the battery 23 can be charged after electricity in the battery 23 has been consumed. Thus, it is possible to secure sufficient electricity to be supplied to the motor 13 next time. The hybrid motorcycle 1 according to this embodiment is arranged to use a higher one of the first rotational speed obtained based on the accelerator operation amount and the second rotational speed obtained based on the accelerator operation speed. Thus, according to the hybrid motorcycle 1, the power from the motor 13 can be applied to the automatic centrifugal clutch 16 at an appropriate timing in accordance with the accelerator operation speed, even if the accelerator grip 9 is operated to fully open the throttle valve 32 in order for the vehicle to start running or accelerate. As a result, in the hybrid motorcycle 1, the power from the engine 12 and the auxiliary power from the motor 13 can be more reliably transmitted to the rear wheel 5. The hybrid motorcycle 1 according to this embodiment is arranged to rotate the motor 13 in conjunction with the rotation of the engine 12 after an engine start and in an operating state where the power from the motor 13 is not applied to the crankshaft 36. Thus, according to the hybrid motorcycle 1, it is possible 36 to prevent the motor 13 not generating auxiliary power from serving as a load on the engine 12, which stabilizes the rotation of the engine 12 in an idling state. In the hybrid motorcycle 1 according to this embodiment, the motor 13 is rotated after the start of the engine 12 and before the speed of the engine 12 reaches an idling speed, which reduces a load on the engine 12. Thus, the engine 12 shifts to an idling state while rotating stably after an engine start, even if the motor 13 is connected to the crankshaft 36. As a result, according to the hybrid motorcycle 1, the series of operations, including starting the engine 12 and the vehicle starting running and accelerating, can be performed smoothly. In the hybrid motorcycle 1 according to this embodiment, if the charge level of the battery 23 is low, the battery 23 can be charged when auxiliary power from the motor 13 is not necessary, for example when the vehicle is at a halt. Thus, according to the hybrid motorcycle 1, the battery 23 can be prevented from being over-discharged, and it is possible to secure electricity for use to cause the motor 13 to generate auxiliary power next time. In the above embodiment, the rotor 38 of the motor 13 is mounted on the crankshaft 36. However, the motor 13 may be formed separately from the engine 12 . In such a case, the rotary shaft of the motor 13 and the crankshaft 36 may be connected directly or via a transmission means that can maintain the ratio 37 between the speeds of both the shafts to a constant value. In the above embodiment, both the accelerator operation amount and the accelerator operation speed are used to set the engagement completion rotational speed. However, only the accelerator operation amount may be used to set the engagement completion rotational speed. Also, in the above embodiment, the driving current supplied to the motor 13 in order to cause the motor 13 to generate auxiliary power is increased and decreased in proportion to the accelerator operation amount. However, the driving current may be increased and decreased in consideration of the accelerator operation speed as well. In the above embodiment, the present invention is applied to a scooter. However, the present invention is not limited thereto, and may be applied to other types of motorcycle. 38 WHAT IS CLAIMED IS: 1. A hybrid motorcycle having an automatic centrifugal clutch interposed in a power transmission system between an engine and a driving wheel, and a motor for auxiliary power connected to a crankshaft of the engine, the motor having a power generation function and also being supplied with electricity from a battery to rotate, the hybrid motorcycle comprising: an acceleration data acquisition means for acquiring as acceleration data at least an accelerator operation amount of an accelerator operating element, of accelerator operation amount and accelerator operation speed thereof; a rotational speed detection means for detecting a rotational speed of the crankshaft or a rotary body for rotation in sync with the crankshaft; a rotational speed estimation means for estimating an engagement completion rotational speed, which is a rotational speed at which the automatic centrifugal clutch is completely engaged, according to the acceleration data acquired by the acceleration data acquisition means; and a motor control means for supplying the motor with a magnitude of electricity in accordance with the acceleration data when the rotational speed detected by the rotational speed detection means has reached the engagement completion rotational speed estimated by the rotational speed estimation means. 39 2. The hybrid motorcycle as claimed in Claim 1, further comprising: an electricity supply restriction means for continuing supply of electricity to the motor for a predetermined electricity supply time and discontinuing the supply of electricity to the motor after the electricity supply time has elapsed. 3. The hybrid motorcycle as claimed in Claim 2, further comprising: a charge level detection means for detecting a charge level of the battery, wherein the electricity supply restriction means shortens the electricity supply time as the charge level detected by the charge level detection means becomes lower. 4. The hybrid motorcycle as claimed in Claim 2, further comprising: a charging means for causing the motor to generate electricity after the electricity supply time has elapsed and charging the battery with the generated electricity. 5. The hybrid motorcycle as claimed in Claim 1, wherein the acceleration data acquisition means acquires 40 the accelerator operation amount and the accelerator operation speed as the acceleration data, and the rotational speed estimation means estimates the engagement completion rotational speed based on a higher one of a first rotational speed and a second rotational speed, the first rotational speed being obtained based on the accelerator operation amount acquired by the acceleration data acquisition means, and the second rotational speed being obtained based on the accelerator operation speed acquired by the acceleration data acquisition means. 6. The hybrid motorcycle as claimed in Claim 1, wherein the motor control means comprises a prerotation means for rotating the motor in conjunction with rotation of the engine after an engine start and in an operating state in which power from the motor is not applied to the crankshaft. 7. The hybrid motorcycle as claimed in Claim 6, wherein a rotation start timing, at which the prerotation means rotates the motor in conjunction with rotation of the engine, is set to a timing after an engine start and when an engine speed is lower than an idling speed. 8. The hybrid motorcycle as claimed in Claim 6, further comprising: 41 a charge level determination means for determining whether or not the charge level of the battery is lower than a predetermined minimum charge level; and 42 a precharging means for causing the motor to generate electricity and charging the battery with the generated electricity after an engine start and in an operating state in which power from the motor is not applied to the crankshaft, if the charge level determination means determines that the charge level of the battery is lower than the minimum charge level. An automatic centrifugal clutch 16 is interposed in a power transmission system between an engine 12 and a driving wheel. A motor 13, which has a function to generate electricity and also is supplied with electricity from a battery 23 to generate auxiliary power, is connected to a crankshaft 36 of the engine 12. An acceleration data acquisition means is provided for acquiring the accelerator operation amount and the accelerator operation speed. A rotational speed detection means is provided for detecting the speed of the crankshaft 36. A rotational speed estimation means is provided for estimating the engagement completion rotational speed, which is a rotational speed at which the automatic centrifugal clutch 16 is completely engaged, according to the acceleration data acquired by the acceleration data acquisition means. A motor control means is provided for supplying the motor 13 with a magnitude of electricity in accordance with the acceleration data when the rotational speed detected by the rotational speed detection means has reached the engagement completion rotational speed estimated by the rotational speed estimation means.

Documents:

01028-kol-2007-abstract.pdf

01028-kol-2007-claims.pdf

01028-kol-2007-correspondence others 1.1.pdf

01028-kol-2007-correspondence others 1.2.pdf

01028-kol-2007-correspondence others 1.3.pdf

01028-kol-2007-correspondence others.pdf

01028-kol-2007-description complete.pdf

01028-kol-2007-drawings.pdf

01028-kol-2007-form 1.pdf

01028-kol-2007-form 18.pdf

01028-kol-2007-form 2.pdf

01028-kol-2007-form 3.pdf

01028-kol-2007-form 5.pdf

01028-kol-2007-others.pdf

01028-kol-2007-pa.pdf

01028-kol-2007-priority document.pdf

1028-KOL-2007-(13-07-2012)-CORRESPONDENCE.pdf

1028-KOL-2007-(24-10-2011)-ABSTRACT.pdf

1028-KOL-2007-(24-10-2011)-AMANDED CLAIMS.pdf

1028-KOL-2007-(24-10-2011)-DESCRIPTION (COMPLETE).pdf

1028-KOL-2007-(24-10-2011)-DRAWINGS.pdf

1028-KOL-2007-(24-10-2011)-EXAMINATION REPORT REPLY RECIEVED.pdf

1028-KOL-2007-(24-10-2011)-FORM 1.pdf

1028-KOL-2007-(24-10-2011)-FORM 3.pdf

1028-KOL-2007-(24-10-2011)-OTHERS.pdf

1028-KOL-2007-(25-01-2012)-PETITION UNDER RULE 137.pdf

1028-KOL-2007-CORRESPONDENCE 1.1.pdf

1028-KOL-2007-CORRESPONDENCE.pdf

1028-KOL-2007-EXAMINATION REPORT.pdf

1028-KOL-2007-FORM 3.pdf

1028-KOL-2007-FORM 5.pdf

1028-KOL-2007-GRANTED-ABSTRACT.pdf

1028-KOL-2007-GRANTED-CLAIMS.pdf

1028-KOL-2007-GRANTED-DESCRIPTION (COMPLETE).pdf

1028-KOL-2007-GRANTED-DRAWINGS.pdf

1028-KOL-2007-GRANTED-FORM 1.pdf

1028-KOL-2007-GRANTED-FORM 2.pdf

1028-KOL-2007-GRANTED-LETTER PATENT.pdf

1028-KOL-2007-GRANTED-SPECIFICATION.pdf

1028-KOL-2007-OTHERS.pdf

1028-KOL-2007-PA.pdf

1028-KOL-2007-PRIORITY DOCUMENT.pdf

1028-KOL-2007-REPLY TO EXAMINATION REPORT.pdf

1028-KOL-2007-TRANSLATED COPY OF PRIORITY DOCUMENT.pdf