Title of Invention

"LAMP VOLTAGE REGULATOR"

Abstract

[OBJECT] To provide a lamp voltage regulator capable of suppressing magnetic friction [CONSTITUTION] A lamp voltage regulator comprises a switching means (91) inserted in a closed circuit having an ac generator (116) and a lamp load (30), a chargeable discharging means (92, 93) connected in parallel to the lamp load (30) so as to be charged by an output of the ac generator (116) when the switching means (91) is shorted and to self-discharge after being charged, and a control means for comparing a predetermined voltage based on an output voltage of the ac generator (116) and a charging voltage for charging the chargeable discharging means (92, 93), and opens the switching means (91) if the charging voltage is higher than the predetermined voltage or shorts the switching means (91) when the charging voltage drops due to discharge below the predetermined voltage. [SELECTED DRAWING]

Full Text

The present invention relates to a lamp voltage regulator. The present invention relates to a voltage regulator for regulating the voltage of power supplied to a lamp load by an ac generator combined with an internal combustion engine for a vehicle or the like. [Description of the Related Art] Power generated by an ac generator is used for charging a battery and for driving loads including lamps. The voltage of the power to be supplied to a lamp load is regulated to protect the lamps. A prior art disclosed in JP-B No. 4-63640 for such a purpose will be described with reference to Fig. 5. A series circuit of a lamp 02 and a lamp switch 03 is connected in parallel to a power generating coil 01. A thyristor 04 is connected in parallel to the power generating coil 01. A parallel circuit of a resistor 06 and a capacitor 07 is connected across the output terminals of a full-wave rectifier 05 connected across the power generating coil 01. One of the output terminals of the full-wave rectifier 05 is connected to the base terminal of a transistor 08, the other output terminal of the full-wave rectifier 05 is connected to the emitter terminal of the transistor 08. The collector terminal of the transistor 08 is connected through a resistor 09 to one end of the power generating coil 01 (the cathode terminal of the thyristor 04) and to the trigger terminal of the thyristor 04. When the lamp switch 03 is closed and the power generated by the power generating coil 01 is in a positive voltage cycle and the ac voltage is positive, the thyristor 04 is in the OFF state and a current flows through the lamp 02 to turn on the lamp 02. The thyristor 04 remains in the OFF state and a current flows through the lamp 02 in an initial stage of a negative voltage cycle of the power generated by the power generating coil 01. The waveform of the output voltage of the full-wave rectifier 05 is smoothed and delayed by the capacitor 07 and the transistor 08 becomes the ON state. Then, the a pulse is applied to the trigger terminal of the thyristor 04, the thyristor 04 become conductive and power supply to the lamp 02 is stopped. Thus, the current is limited while the power is in the negative voltage cycle to regulate the voltage applied to the lamp 02. [Problem to be Solved by the Invention] This prior art makes the switching means, i.e., the thyristor 04, conducive to regulate the voltage applied to the lamp 02 by making the current flowing through the lamp flow through the switching means. A closed circuit through which a current flows while the thyristor 04 is in the ON state has the power generating coil 01 and the thyristor 04 having very small resistances which consumes the power generated in the power generating coil 01. Therefore a high short-circuit current flows through the closed circuit. The high short-circuit current produces a magnetic friction which deteriorates fuel consumption. A power system included in a vehicle which stops its engine when the same stops and drives a starter motor when starting the engine employs a magnet having a high coercive force, such as a neodymium magnet, to produce a •necessary starter torque every time the engine is started and to enhance battery charging capacity, which increases the short-circuit current and magnetic friction to deteriorate fuel consumption. Uhe present invention has been made in view of the foregoing problems and it is an object of the present invention to provide a lamp voltage regulator capable of suppressing magnetic friction. [Means for solving the Problem,Function and Effect] With the foregoing object in view, the present invention provides §. lamp voltage regulator comprising: a switching means inserted in a closed circuit having an ac generator and a lamp load; a chargeable discharge means connected in parallel to the lamp load so as to be charged by an output of the ac generator when the switching means is shorted and to self-discharge after being charged characterized in that a control means for comparing a predetermined voltage based on an output voltage of the ac generator with a charging voltage for charging the chargeable discharge means, and opens the switching means if the charging voltage is higher than the predetermined voltage or shorts the switching means when the charging voltage drops due to discharge below the predetermined voltage. The closed circuit including the ac power generator and the lamp load is provided with the switching means, a current flows through the lamp load to turn on the light load when the switching means is shorted, and current supply to the lamp load is stopped when the switching means is open. The chargeable discharge means connected in parallel to the lamp load is charged while the switching means is shorted, and the chargeable discharge means discharges while the switching means is open, and the switching means is shorted when the charged voltage drops due to discharge below the predetermined voltage to supply power to the lamp load. Since a short-circuit current supplied by the ac generator flows through the lamp load when the switching means is shorted, the short-circuit current will not increase excessively, magnetic friction can be suppressed and fuel consumption will not be deteriorated. According to an invention stated in claim 2, in the lamp voltage regulator stated in claim 1, an output current of the ac generator flows through a predetermined resistor means while the charging voltage is higher than the predetermined voltage and the switching means is open. While the switching means is open, the output current of the ac generator flows through the predetermined resistor means so that an excessively high current may not flow to suppress magnetic friction while the switching means is open. According to an invention stated in claim 3, in the lamp voltage regulator stated in claim 1, the control means is provided with a constant-voltage means for maintaining the predetermined voltage on the basis of the output voltage of the ac generator. The constant-voltage means maintains the predetermined voltage on the basis of the output voltage of the ac generator, the charging voltage for charging the chargeable discharge means is lower than the predetermined voltage, and the voltage applied to the lamp load is regulated by regulating the timing of shorting the switching means. [BRIEF DESCRIPTION OF THE DRAWING] [Fig. 1] Fig. 1 is a general side view of a scooter type motorcycle provided with a lamp voltage regulator in a preferred embodiment according to the present invention, in which come components are omitted. [Fig. 2] Fig. 2 is a sectional view of an internal combustion engine included in the scooter type motorcycle of Fig. 1 taken on line II-II in Fig. 1. [Fig. 3] Fig. 3 is a circuit diagram of a start control system. [Fig. 4] Fig. 4 is a waveform diagram showing the waveform of a voltage to be applied to a lamp. [Fig. 5] Fig. 5 is a circuit diagram of a prior art lamp voltage regulating circuit. [Description of the Preferred Embodiment] A preferred embodiment of the present invention will be described hereinafter with reference to Figs. 1 to 4. Fig. 1 shows, in a general side view, a scooter type motorcycle provided with a lamp voltage regulator in the preferred embodiment. The scooter type motorcycle 1 is provided with a two-stroke cycle internal combustion engine. A front body part 2 and a rear body part 3 are interconnected by a low floor part 4. A body frame, i.e., a skeletal body, comprises, as principal components, a down tube 6 and a main pipe 7. A fuel tank and a parcel box are supported on the main pipe 7, and a seat 8 is disposed over the main pipe 7. In the front body part 2, a handlebar 11 is supported for turning in a steering head 5. A front fork 12 extends downward from the steering head 5, and a front wheel 13 is supported on the lower end of the front fork 12. A lamp unit provided with a lamp 30 is disposed in front of a middle part of the handlebar 11. A handgrip 61 (Fig. 3), i.e., an accelerator grip, is attached to a right end part of the handlebar 11. A bracket 15 is attached to a lower end part of a rising section of the main pipe 7, and a swing unit 17 is connected for swing motion to a link 16 pivotally joined to the bracket 15. The two-stroke cycle single-cylinder internal combustion engine 200 is mounted on a front part of the swing unit 17. A belt-drive continuously variable speed transmission 35 extends backward from the internal combustion engine 200, a reduction mechanism 38 is interlocked with a rear part of the belt-drive continuously variable speed transmission 35 by a centrifugal clutch, and a rear wheel 21 is supported for rotation on the reduction mechanism 38. A rear shock absorber 22 is extended between the upper end of the reduction mechanism 38 and a bend formed in an upper part of the main pipe 7. A carburetor 24 connected to an intake pipe 23 connected to an upper part of the cylinder head of the internal combustion engine 200, and an air cleaner 25 connected to the carburetor 24 are disposed above the swing unit 17. A main stand 26 is pivotally joined to a hanger bracket 18 projecting from a unit swing case 31. A base end of a kick arm 28 is fixedly mounted on a kick shaft 27 projecting from a transmission case 36 of the belt-drive continuously variable speed transmission 35, and a kick pedal 29 is attached to the free end of the kick arm 28. Fig. 2 is a sectional view of the internal combustion engine 200 of Fig. 1 taken on line II-II in Fig. 1. The internal combustion engine 200 is assembled by combining right and left half cases supporting a crankshaft 201 for rotation in a horizontal position to construct a crankcase 202, attaching a cylinder block 203 to the crankcase 202, and attaching a cylinder head 204 to the cylinder block 203. The cylinder block 203 has an exhaust passage, not shown, a scavenging port, not shown, opening into a cylinder bore, and a scavenging passage 205 connecting the scavenging port to the crank chamber of the crankcase 202. A ignition plug 206 is attached to the cylinder head 204 so as to be directed toward the combustion chamber. The cylinder head 204 and the cylinder block 203 excluding an exposed part of the ignition plug 206 are covered with a fan shroud 207. The left half crankcase 202L serves also as a case for covering the belt-drive continuously variable speed transmission 35. A crankshaft 201 extends through the left half crankcase 202L, and a drive pulley 210 is fixedly mounted on the crankshaft 201 for rotation together with the crankshaft 201. The drive pulley 210 consists of an axially fixed part 210L and an axially movable part 21OR. A boss 211 formed on the axially fixed part 210L is fastened to a left end part of the crankshaft 201. The axially movable part 210R is interlocked with the crankshaft 201 by splines so as to be axially movable toward and away from the axially fixed part 210L. A V belt 212 is wound around the drive pulley 210 so as to be received in a groove formed between the parts 210L and 21 OR. A cam plate 215 is fixed to the crankshaft 201 at a position on the right side of the axially movable part 210R. A slide block 215a attached to a peripheral part of the cam plate 215 is in sliding engagement with a cam plate guide part 210Ra axially protruding from a peripheral part of the axially movable part 21OR. The axially movable part 210R has a conical side surface facing the cam plate 215 and tapered in a direction away from the cam plate 215. A dry weight roller 216 is disposed in a space between the conical side surface of the axially movable part 210R and the cam plate 215. As the rotating speed of the crankshaft 201 increases, the dry weight roller 216 interposed between the axially movable part 21 OR and the cam plate 215 is moved radially outward by centrifugal force, whereby the axially movable part 21OR is pushed toward the axially fixed part 210L, i.e., toward the left as viewed in Fig. 2, by the dry weight roller 216 to push the V belt 212 fitted in a space between the parts 21OR and 210L so that the pitch diameter of the drive pulley 210 is increased. The V belt 212 is extended between the drive pulley 210 and a driven pulley, not shown, to transmit automatically regulated power through a centrifugal clutch to the reduction mechanism to drive the rear wheel. A transmission case cover 220 covers the open left end of a belt-drive continuously variable transmission chamber and extends rearward from a position corresponding to the drive pulley 210. The kick shaft 27 is extended through and supported on a front part of the transmission case cover 220. A driving helical gear 222 is mounted on an inner end part of the kick shaft 27, and the kick shaft 27 is biased toward a starting position by a return spring 223. An axially movable shaft 224 is supported for rotation coaxially with the crankshaft 201 on the inner surface of a front part of the transmission case cover 220. A driven helical gear 225 formed integrally with the axially movable shaft 224 is in engagement with the driving helical gear 222. A ratchet wheel 226 is fixed to a right end part of the axially movable shaft 224. The axially movable shaft is biased toward the left, as viewed in Fig. 2 by a friction spring 227. Ratchets are formed in a surface of the boss 211 fixed to the crankshaft 201 facing the ratchet wheel 226. The ratchet wheel 226 and ratchets of the boss 211 are engaged when the axially movable shaft 224 is forced toward the boss 211 and are disengaged when the axially movable shaft 224 is moved away from the boss 211. When the kick pedal 29 is stepped on to turn the kick shaft 27 against the resilience of the return spring 223, the driving helical gear 222 fixed to the kick shaft 27 and engaged with the driven helical gear 225 turns the axially movable shaft 224 fixed to the driven helical gear 225 and forces the same toward the right against the resilience of the spring 227. Consequently, the ratchet wheel 226 and ratchets of the boss 211 are engaged, whereby the crankshaft 201 is driven for rotation to start the internal combustion engine 200. A substantially cylindrical right half crankcase 202R extends on the right side of main bearings 209 supporting the crankshaft 201 for rotation, and a right part of the crankshaft 201 projects into the right half crankcase 202R coaxially with the latter. A starter dynamotor 110 is disposed in a cylindrical space defined by the right half crankcase 202R. An inner rotor (magnet rotor) 111 is put on a tapered end part of the crankshaft 201 and is fixedly held in place with a nut 113 for rotation together with the crankshaft 201. Six grooves having a circular cross section are formed in the outer circumference of the inner rotor 111, and magnets 112 of neodymium-iron-boron are fitted in the grooves, respectively. A cylindrical outer stator 115 is disposed so as to surround the inner rotor 111, and is fastened to the cylindrical wall 202a of the crankcase 202 with bolts 119. The stator core of the outer stator 115 is constructed by laminating thin steel plates, and a power generating coil 116 and a starting coil 117 are wound on a plurality of yokes projecting radially inward from the annular wall of the stator core. The power generating coil 116 and the starting coil 117 projecting axially inward in the cylindrical wall 202a of the crankcase 202 form an annular coil structure, and a commutator brush mechanism 120 is disposed in a space defined by the annular coil structure. In the space defined by the annular coil structure, a brush holder 121 is put on the crankshaft 201 for axial movement and is restrained from turning relative to the crankshaft 201. A spring 123 is disposed between the inner rotor 111 and the brush holder 121 to bias the brush holder 121 axially inward. A plurality of brushes 122 are supported at predetermined positions on the brush holder 121 and are biased by springs so as to project from the inner side surface of the brush holder 121. A commutator holder 125 is disposed opposite to the inner side surface of the brush holder 121. The outer periphery of the commutator holder 125 is fixedly held on the power generating coil 116 and the starting coil 117 projecting axially inward. The crankshaft 201 extends through the respective central holes of the brush holder 121 and the commutator holder 125. Commutator bars 126 are disposed at predetermined positions on concentric circles on the surface of the commutator holder 125 facing the brush holder 121. The brush holder 121 which rotates together with the crankshaft 201 moves toward and away from the fixed commutator holder 125. When the brush holder 121 approaches the commutator holder 125, the brushes 122 come into contact with the corresponding commutator bars 126. An axially outer part of the inner rotor 111 has an inner cylindrical part 131 extending axially outward so as to surround the nut 113 screwed on the end part of the crankshaft 201, and an outer cylindrical part 132 coaxial with and surrounding the inner cylindrical part 131. A governor mechanism 130 is constructed there. The outer cylindrical part 132 has a tapered inner surface and serves as an outer governor disk. An axially movable inner governor disk 133 is fitted on the inner cylindrical part 131. A ball 134 serving as a governor weight is placed in a space between the outer cylindrical part 132 and the inner governor disk 133. A connecting bar 135 extending in parallel to the crankshaft 201 through the inner rotor 111 has one end fixed to the axially movable inner governor disk 133 of the governor mechanism 130, and the other end attached to the brush holder 121. The connecting bar 135 connects the inner governor disk 133 and the brush holder 121 for axial movement in parallel to the crankshaft 201. As shown in Fig. 2, the brush holder 121 is biased axially inward by the spring 123 and the brushes 122 are in contact with the commutator bars 126 while the crankshaft 201 is stationary. Accordingly, a current supplied from a battery flows through the brushes 122, the commutator bars 126 and the starting coil 117, a torque is applied to the inner rotor 111 to rotate the crankshaft 201, so that the internal combustion engine 200 is started. As the engine speed increases, centrifugal force acting on the ball 134 increases to move the ball 134 radially outward along the tapered inner surface of the outer cylindrical part 132, so that the inner governor disk 133 is forced axially outward. Consequently, the brush holder 121 connected by the connecting bar 135 to the inner governor disk 133 is moved axially outward. When the engine speed increases beyond a predetermined engine speed, the brushes 122 are separated automatically from the commutator bars 126 and, thereafter, power generated in the power generating coil 116 is used for charging the battery and for lighting the lamp. A rotor 140 for crank angle sensing having the shape of an annular plate is fixedly fitted on the circumference of the outer cylindrical part 132. A pulser 141 disposed at a predetermined position close to the outer circumference of the rotor 140 is fixed to the crankcase 202. The pulser 141 detects a notch formed in the outer circumference of the rotor 140 rotating together with the inner rotor 111 and the crankshaft 201 to find a crank angle. The rotor 140 having the shape of an annular plate covers the outer side surfaces of the power generating coil 116 and the starting coil 117 mounted on the outer stator 115. A fan 145 of a blower for the forced air-cooling of the internal combustion engine is attached to the axially outer side surface of the rotor 140. The skirt of the central conical part 145a of the fan 145 is fastened to the outer cylindrical part 132 of the inner rotor 111 with bolts 146. Blades 145b arranged around the central conical part 145a extend on the outer side of the rotor 140. The fan 145 is covered with a cover 148. The cover 148 is provided with an air inlet opening 148a on the outer side of the fan 145, and has a guide wall 148b for guiding air taken in through the air inlet opening 148a toward the cylinder block 203 and the cylinder head 204. The starter dynamotor 110 relating to the embodiment of the present invention is thus constructed; the commutator brush mechanism 120 is disposed on the axially inner side of the inner rotor 111, and the governor mechanism 130 is disposed on the axially outer side of the inner rotor 111. A start control system for the internal combustion engine 200 provided with the starter dynamotor 250 for directly driving the crankshaft 201 for rotation will be described with reference to Fig. 3. Shown also in Fig. 3 are a charging circuit 80 for charging the battery 50, and a lamp voltage regulating circuit 90 for regulating voltage applied to the lamp 30, which will be described later. The positive terminal of the battery 50 is connected through a combination switch 51 to an ignition stop unit 70, a stationary contact 62a of a throttle switch 62 included in a power feed unit 60, and a contact 63a of a starter solenoid switch 63 included in the power feed unit 60. The throttle switch 62 is formed on the handgrip 61, and has the stationary contact 62a and a circular contact 62b attached to the handgrip 61. The contacts 62a and 62b are always in contact with each other except when the throttle valve is fully closed. The circular contact 62b is connected to one end of the solenoid 63c of the starter solenoid switch 63, and the other end of the solenoid 63c is grounded through a brake switch 64. Another contact 63b of the starter solenoid switch 63 is connected to a conductor of the starter dynamotor 110 and one of the input terminals of a NOR circuit 71 included in the ignition stopping unit 70. When the handgrip 61 is turned to open the throttle valve in a state where the combination switch 51 is closed, the brake is applied and the brake switch 64 is closed, a current flows through the solenoid 63c of the power feed unit 60, the starter solenoid switch 63 is closed, power is supplied to the starter dynamotor 110 to drive the starter dynamotor 110 for operation as a starter motor, and an H signal, i.e., a signal of a high level, is applied to the input terminal of the NOR circuit 71 of the ignition stopping unit 70. The internal combustion engine 200 can be started simply by turning the handgrip 61 in a state where the brake is applied without operating any starting device, such as a starter button. A signal indicating whether or not the rear wheel 21 is rotating, i.e., whether or not the traveling speed is zero, is applied to the other input terminal of the NOR circuit 71 of the ignition stopping unit 70. The signal is L (low) if the traveling speed is zero or H (high) if the traveling speed is not zero. The output of the NOR circuit 71 is applied to one of the input terminal of a NAND circuit 72. A signal indicating the condition of a by-starter 54 incorporated into the carburetor 24, i.e., a signal indicating whether or not the internal combustion engine 200 has been warmed up. This signal is L if the internal combustion engine 200 has not been warmed up or H if the internal combustion engine 200 has been warmed up. The output terminal of the NAND circuit 72 is connected to the base terminal of a transistor 73. The collector terminal of the transistor 73 of the ignition stopping unit 70 is connected to the combination switch 51, and the emitter terminal of the same is connected to the power input terminal of a GDI unit (capacitive discharge ignition unit) 52. The output terminal of the GDI unit 52 is connected to an ignition coil 53 for applying a high voltage to the ignition plug 206. The signals applied to the two input terminals of the NOR circuit 71 go L, so that the signal applied to one of the input terminals of the NAND circuit 72 goes H if the throttle valve is fully closed and the traveling speed is zero, and, if the internal combustion engine 200 has been warmed up, the signal applied to the other input terminal of the NAND circuit 72 goes H. Consequently, the output signal of the NAND circuit 72 goes L, the signal applied to the base terminal of the transistor 73 goes L, and hence the transistor 73 is turned off. Consequently, any current is not supplied to the GDI unit 52 and ignition is stopped. When any one of the conditions that the throttle valve is fully closed, the traveling speed is zero and the internal combustion engine 200 has been warmed up is not met, the output of the NAND circuit 72 goes H, and the transistor 73 is turned on to enable ignition. Since the start control system is thus constructed, the ignition stopping unit 70 stops ignition to stop the internal combustion engine 200 when the motorcycle I stops traveling because the traveling speed drops to zero when the throttle valve is fully closed and the brake is applied, and the internal combustion engine 200 is warmed up. Thus, even if the motorcycle is stopped temporarily in conformity to a traffic signal, the internal combustion engine 200 is stopped to avoid wasting fuel. If the handgrip 61 is turned to increase throttle opening in a state where the brake is applied (the brake switch 64 is closed), the starter solenoid switch 63 is closed to supply power to the starting coil 117 of the starter dynamotor 110, the starter dynamotor 110 functions as a starter motor, the signal applied to the input terminal of the NOR circuit 71 of the ignition stopping unit 70 goes H, the transistor 73 is turned on, the ignition plug 206 is energized to start the internal combustion engine 200. Since the starter dynamotor 110 drives the crankshaft 201 directly to start the internal combustion engine 200, the crankshaft 201 can be instantly rotated without generating any noise, so that the internal combustion engine 200 can be smoothly started. When the rotating speed of the crankshaft 201 increases beyond a predetermined rotating speed after the internal combustion engine 200 has been started, the supply of power to the starter dynamotor 110 is stopped by the governor mechanism 130, so that the engine speed increases in an instant to a level corresponding to a throttle opening determined by operating the handgrip 61. Thus the internal combustion engine 200 can be started simply by operating the handgrip 61 after the motorcycle 1 has been temporarily stopped, and the engine speed increases according to throttle opening. Consequently, the centrifugal clutch interlocked with the rear wheel 21 is engaged and the motorcycle I can be immediately started when the brake is released. Thus the motorcycle can be smoothly and instantly started by a simple operation even though the operation of the internal combustion engine 200 is stopped when the motorcycle is stopped temporarily to avoid wasting fuel. The ignition stopping unit 70 stops ignition when the motorcycle 1 is stopped temporarily during traveling, in which throttle valve is fully closed, the traveling speed of the motorcycle 1 is zero and the internal combustion engine 200 is warmed up. However, if the internal combustion engine 200 needs a warm-up, the ignition stopping unit 70 does not stop ignition until the internal combustion engine 200 is warmed up. The start control system needs to drive the starter dynamotor 110 every time the motorcycle 1 is started and hence the starter dynamotor 110 must have a high charging capacity sufficient for charging the battery 50. Therefore, the starter dynamotor 110 employs the neodymium-iron-boron magnets 112 having a high coercive force. The power generating coil 116 of the starter dynamotor 110 has one end connected to a ground and the other end connected to a thyristor 81 of the charging circuit 80 for charging the battery 50 by power generated in the power generating coil 116 of the starter dynamotor 110. The thyristor 81 is connected to the terminal of the combination switch 51. A series circuit of a diode 82 and a resistor 83 is connected to the gate of the thyristor 81, and the joint of the diode 82 and the resistor 83 is connected through a diode 84 and a Zener diode 85 to the ground. When the combination switch 51 is closed, the charging circuit 80 regulates the voltage of ac power generated in the power generating coil 116 at a predetermined voltage, rectifies the ac power in a half-wave rectification mode, and charges the battery 50 while the ac power is in the positive voltage cycle. The lamp voltage regulating circuit 90 for regulating voltage applied to the lamp 30 will be described hereinafter. A thyristor 91 has an anode terminal connected to the ground and a cathode terminal connected to one of the terminals of the lamp 30. The other terminal of the lamp 30 is connected to the power generating coil 116 of the starter dynamotor 110. The power generating coil 116, the thyristor 91 and the lamp 30 constitute a closed circuit. A chargeable discharge circuit is formed by connecting a resistor 92 and a capacitor 93 in parallel. A circuit formed by connecting a resistor 94 and a diode 95 to the opposite ends of the chargeable discharge circuit, respectively, is connected in parallel to the lamp 30. A Zener diode 96, a diode 97 and a resistor 98 are connected in that order to the anode terminal of the diode 95, and the resistor 98 has one end connected to the grounded. The other end of the resistor 98 is connected through a diode 99 to the gate terminal of the thyristor 91. The operation of the lamp voltage regulating circuit 90 will be described with reference to Fig. 4 showing the variation of ac power generated in the power generating coil 116. When the ac power is in the positive voltage cycle, the thyristor 91 is in the OFF state and any current is supplied to the lamp 30. The diode 95 is in the OFF state and hence the chargeable discharge circuit formed by connecting the resistor 92 and the capacitor 93 in parallel is not charged. In the first negative voltage cycle of the ac power (a shaded section LI in Fig. 4), a forward voltage is applied to the thyristor 91 to apply a trigger voltage through the resistor 98 and the diode 99 to the gate terminal of the thyristor 91. Consequently, the thyristor 91 is turned on to supply power to the lamp 30. When the thyristor 91 is switched to the ON state, a current is supplied to the chargeable discharge circuit formed by connecting the resistor 92 and the capacitor 93 in parallel, and the capacitor 93 is charged. In the next positive voltage cycle, the thyristor 91 is switched to the OFF state and any power is not supplied to the lamp 30. The positive current is intercepted by the diode 95 and does not affect the chargeable discharge circuit, and the capacitor 93 discharges through the resistor 92. In the next negative voltage cycle, a reverse voltage is applied to the thyristor 91 to keep the thyristor 91 in the OFF state while the voltage of the capacitor 93 of the chargeable discharge circuit is higher than a predetermined voltage of the Zener diode 96. In this state, a current flows through the resistor 98, the diode 97, the Zener diode 96 and the diode 95 in that order. This current flows through the resistor 98 having a relatively large resistance, and hence the magnitude of the current is small and power consumption is very small. When the voltage of the capacitor 93 of the chargeable discharge circuit drops due to discharge below the predetermined voltage of the Zener diode 96, a trigger voltage is applied through the resistor 98 and the diode 99 to the gate terminal of the thyristor 91, so that the thyristor 91 is switched to the ON state to supply power to the lamp 30 (shaded section L2 in Fig. 4). The lamp voltage regulating circuit 90 supplies power to the lamp 30 to turn on the lamp 30 when the thyristor 91 is in the ON state, and regulates the voltage through the control of the timing of switching the thyristor 91 to the ON state by the chargeable discharge circuit and the Zener diode 96. This scooter type motorcycle 1 employs the start control system which stops the internal combustion engine when the motorcycle 1 stops traveling and drives the starter dynamotor every time the motorcycle 1 is started. Therefore, the starter dynamotor 110 employs the neodymium-iron-boron magnets 112 having a high coercive force, which has tendency to increase the short current of the power generating coil 116 and to increase magnetic friction. However, since the lamp voltage regulating circuit 90 supplies a short current which flows when the thyristor 91 is switched to the ON state to the lamp 30, the short current will not increase excessively and the magnetic friction can be suppressed to prevent the deterioration of fuel consumption. When the thyristor 91 is in the OFF state, only a small current flows through the resistor 98 of the lamp voltage regulating circuit 90, and hence the magnetic friction is low and does not affect fuel consumption significantly. The lamp voltage regulating circuit 90 is very effective for a vehicle provided with the start control system which drives the starter dynamotor every time the vehicle is to be started. [REFERENCE CHARACTERS] 1 ... Scooter type motorcycle, 2 ... Front body part, 3 ... Rear body part, 4 ... Floor part, 6 ... Down tube, 7 ... Main pipe, 8 ... Seat, 11 ... Handlebar, 12 .. Front fork, 13 ... Front wheel, 15 ... Bracket, 16 ... Link, 17 ... Swing unit, 18 ... Hanger bracket, 21 ... Rear wheel, 22 ... Rear shock absorber, 23 ... Intake pipe, 24 ... Carburetor, 25 ... Air cleaner, 26 ... Main stand, 27 ... Kick shaft, 28 ... Kick arm, 29 ... Kick pedal, 30 ... Lamp, 50 ... Battery, 51 ... Combination switch, 52 ... GDI unit, 53 ... Ignition coil, 54 ... By-starter, 60 ... Power feed unit, 61 ... Handgrip, 62 ... Throttle switch, 63 ... Starter solenoid switch, 64 ... Brake switch, 70 ... Ignition stopping unit, 71 ... NOR circuit, 72 ... NAND circuit, 73 ... Transistor, 80 ... Charging circuit, 81 ... Thyristor, 82 ... Diode, 83 ... Resistor, 84 ... Diode, 85 ... Zener diode, 90 ... Lamp voltage regulating circuit, 91 ... Thyristor, 92 ... Resistor, 93 ... Capacitor, 94 ... Resistor, 95 ... Diode, 96 ... Zener diode, 97 — Diode, 98 ... Resistor, 99 ... Diode, 110 ... Starter dynamotor, 111 — Inner rotor, 112 ... Magnet, 113 ... Nut, 115 Outer stator, 116 ... Power generating coil, 117 ...Starting coil, 120 ... Commutator brush mechanism, 121 ... Brush holder, 122 ... Brush, 123 ... Spring, 125 ... Commutator holder, 126 ... Commutator bar, 130 ... Governor mechanism, 131 ... Inner cylindrical part, 132 ... Outer cylindrical part, 133 ... Inner governor disk, 134 ... Ball, 135 ... Connecting bar, 140 ... Rotor, 141 — Pulser, 145 — Fan, 146 — Bolt, 148 — Cover, 200 ... Internal combustion engine, 201 . . . Crankshaft, 202 ... Crankcase, 203 ... Cylinder block, 204 ... Cylinder head, 205 ... Scavenging passage, 206 ... Ignition plug, 210 ... Drive pulley, 211 ... Boss, 212 ... V belt, 215 ... Cam plate, 216 — Dry weight roller, 220 ... Transmission case cover, 222 ... Driving helical gear, 223 ... Return spring, 224 ... Axially movable shaft, 225 ... Driven helical gear, 226 ... Ratchet wheel, 227 — Spring WE CLAIM : 1. A lamp voltage regulator comprising: a switching means inserted in a closed circuit having an ac generator and a lamp load; a chargeable discharge means connected in parallel to the lamp load so as to be charged by an output of the ac generator when the switching means is shorted and to self-discharge after being charged characterized in that a control means for comparing a predetermined voltage based on an output voltage of the ac generator with a charging voltage for charging the chargeable discharge means, and opens the switching means if the charging voltage is higher than the predetermined voltage or shorts the switching means when the charging voltage drops due to discharge below the predetermined voltage. 2. The lamp voltage regulator as claimed in claim 1, wherein an output current of the ac generator flows through a predetermined resistor means when the charging voltage is higher than the predetermined voltage and the switching means is open. 3. The lamp voltage regulator as claimed in claim 1, wherein the control means is provided with a constant-voltage means for maintaining the predetermined voltage on the basis of the output voltage of the ac generator. 4. A lamp voltage regulator substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

Documents:

1758-del-1998-abstract.pdf

1758-del-1998-claims.pdf

1758-del-1998-correspondence-others.pdf

1758-del-1998-correspondence-po.pdf

1758-del-1998-description (complete).pdf

1758-del-1998-drawings.pdf

1758-del-1998-form-1.pdf

1758-del-1998-form-13.pdf

1758-del-1998-form-19.pdf

1758-del-1998-form-2.pdf

1758-del-1998-form-3.pdf

1758-del-1998-form-4.pdf

1758-del-1998-form-6.pdf

1758-del-1998-gpa.pdf

1758-del-1998-petition-138.pdf

abstract.jpg