JP2018193937A - Engine starting device - Google Patents

Abstract

To provide an engine starting device capable of securing engine startability in a simple construction and at a low cost by unifying methods for using a generator motor and a starter at starting an engine.SOLUTION: The engine starting device includes the generator motor connected to a crankshaft of the engine, and the starter having a pinion for engaging with a ring gear provided on the crankshaft at starting the engine. At initial start to start the engine with the starting operation of a driver, the combined cranking of the engine is performed using both the generator motor and the starter, and at restarting the engine, the cranking of the engine is performed using the generator motor.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an engine starter that includes a generator motor connected to a crankshaft of an engine and a starter that meshes a pinion with a ring gear when the engine is started, and cranks the engine by starting at least one of the generator motor and the starter. .

  Conventionally, a generator motor that performs engine cranking when starting an engine in a vehicle that performs engine automatic stop / restart control that automatically stops the engine when the engine stop condition is satisfied and then restarts the engine when the restart condition is satisfied And what is equipped with a starter is known.

  In such a vehicle, in cranking when starting the engine, the generator motor and the starter are selectively used according to the situation, or the generator motor and the starter are used together to start the engine.

  Here, based on information on the engine water temperature and the like, a first starter that is a starter that starts the engine via a gear transmission and a second generator that is a generator motor that starts the engine via a belt transmission 2. Description of the Related Art An engine start control device is known that cranks an engine by selecting whether the start device is used alone or in combination (see, for example, Patent Document 1).

  In the engine start control device described in Patent Document 1, when the engine is cranked using both the first start device and the second start device, the first start device is driven, and then the first start device is driven. The second starter is driven and then the second starter is continuously driven even after the first starter is stopped.

  In addition, in a vehicle that is started by a starter motor that is a starter when the engine is started by operating a key and is always assisted by a motor generator that is a generator motor, the starter motor and the motor generator are There is known a control device for a hybrid vehicle that cranks an engine by selecting whether to use it alone or in combination (see, for example, Patent Document 2).

  In the hybrid vehicle control device described in Patent Document 2, when the engine is cranked using both the starter motor and the motor generator, the starter motor is driven, and then the engine speed is equal to or higher than the set speed. When it becomes, the drive of the motor generator is started. When the engine is restarted with only the motor generator, the motor output value of the motor generator is set to a value exceeding the rated performance.

  Further, based on the requested cranking torque information, the engine is cranked by selecting whether to use the first motor as a generator motor and the second motor as a starter individually or in combination. In addition, the start control device for the internal combustion engine that determines the slip state of the belt after the start of cranking, selects one of the first electric motor and the second electric motor based on the slip state, and cranks the engine until the start is completed. Is known (see, for example, Patent Document 3).

JP 2000-161102 A JP 2002-048036 A JP 2014-134130 A

However, the prior art has the following problems.
That is, in the conventional engine starter, in each engine start situation, the engine cranking by the generator motor, the engine cranking by the starter, and the engine cranking by both the generator motor and the starter are combined with the engine water temperature. It is to be selected based on the power supply voltage or the like.

  For example, in the engine start control device described in Patent Document 1, an engine start method is selected according to the engine water temperature. In other words, even at the initial start when the engine is started by the driver's start operation, the engine water temperature is monitored and cranked with a generator motor, cranked with a starter, or a generator motor and a starter are used in combination. You will choose whether to crank.

  Therefore, it is necessary to perform control for determining a starting method before starting the engine, and a sensor for detecting a water temperature or the like as a determination material is required, which causes a problem that the engine starting device becomes complicated and the cost is increased. .

  In the hybrid vehicle control device described in Patent Document 2, in the case of initial start, the starter is started and the motor is always assisted by the generator motor. Whether the starter and the generator motor are used alone or in combination is selected based on the power supply voltage.

  For this reason, it is necessary to perform control for determining the starting method before restarting the engine, and a sensor for detecting the water temperature or the like as a determination material is required, which complicates the engine starting device and increases costs. is there.

  In the internal combustion engine start control device described in Patent Document 3, it is selected whether the generator motor and the starter are used individually or in combination, according to the required cranking torque. Therefore, it is necessary to perform control for determining a starting method before starting the engine, and a sensor for detecting a water temperature or the like as a determination material is required, which causes a problem that the engine starting device becomes complicated and the cost is increased. .

  The present invention has been made to solve the above-described problems. By unifying the method of using the generator motor and starter at the time of starting the engine, the engine startability can be secured with a simple structure and at a low cost. It is an object of the present invention to obtain an engine starter that can be used.

  The engine starter according to the present invention is mounted on a vehicle that performs engine automatic stop / restart control for automatically stopping the engine when the engine stop condition is satisfied and restarting the engine when the restart condition is satisfied. The generator motor connected to the crankshaft of the engine and a starter that meshes a pinion with a ring gear provided on the crankshaft when the engine is started, and the engine is started by a driver's starting operation. Then, the engine is cranked together with both the generator motor and the starter, and when the engine is restarted, the engine is cranked with the generator motor.

According to the engine starter according to the present invention, in the initial start in which the engine is started by the driver's start operation, the engine is cranked together with both the generator motor and the starter. Crank.
Therefore, by unifying the usage methods of the generator motor and the starter at the time of starting the engine, the engine startability can be ensured with a simple configuration and low cost.

1 is a block diagram showing a schematic configuration of a vehicle equipped with an engine starter according to Embodiment 1 of the present invention. It is sectional drawing which shows the starter of the engine starting apparatus which concerns on Embodiment 1 of this invention. It is a block diagram which shows the one-way clutch of the starter shown in FIG.

  Hereinafter, preferred embodiments of an engine starter according to the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts will be described with the same reference numerals.

Embodiment 1 FIG.
1 is a block diagram showing a schematic configuration of a vehicle on which an engine starter according to Embodiment 1 of the present invention is mounted. In FIG. 1, the engine 1 includes a function of determining engine stop or engine restart of engine automatic stop / restart control, and is driven and controlled by an engine control device 5 that controls the engine 1. Hereinafter, the engine control device 5 is referred to as an engine ECU 5.

  A generator motor 2 is always connected to the crankshaft 11 of the engine 1 via a belt 12. Further, the pinion 31 serving as an output part of the rotational torque of the starter 3 is provided in a detachable state on the ring gear 13 integrated with the crankshaft 11 and transmits the rotational torque.

  A power converter 21 is connected to the generator motor 2. The power converter 21 is connected to the battery 4 and a generator motor control circuit 22 that controls regeneration and power running of the generator motor 2. Hereinafter, the generator motor control circuit 22 is referred to as an MG control circuit 22.

  The starter 3 includes an electromagnetic switch 32 having an electrical contact opening / closing function for supplying power to the starter 3. The electromagnetic switch 32 is connected to the battery 4. A signal for starting the engine is input to the input terminal of the MG control circuit 22 and the excitation terminal of the electromagnetic switch 32, respectively.

  Further, the engine 1 includes a crank angle sensor (not shown) that detects the rotation angle of the crankshaft 11, and a crank angle signal from the crank angle sensor is transmitted to the engine ECU 5 and calculated, and the crankshaft 11 of the engine 1 is calculated. The rotational speed of is derived.

  Next, the function of the generator motor 2 will be described. The generator motor 2 has two functions: a power generation function that is regenerative and a motor drive function that is power running. Here, the regeneration is a case where the engine 1 is in an operating state, and the generator motor 2 is constantly rotating from the crankshaft 11 via the belt 12 by the rotational torque of the engine 1, and the MG control circuit 22. The battery 4 is charged by rectifying the generated power by the power converter 21 controlled by the above.

  The power running is a case where rotational torque is supplied to the engine 1, and the generator motor 2 uses the power of the battery 4 and receives power supply via the power converter 21 controlled by the MG control circuit 22. Driven as a motor. Further, the rotational torque is transmitted to the crankshaft 11 via the belt 12, and the engine 1 is driven.

  The generator motor 2 is switched from power running to regeneration after the start of the engine 1 is completed. In addition, when the rotational torque is supplied to the engine 1, only the generator motor 2 is used when the engine 1 is cranked, when the torque assist is made up for the generated torque of the engine 1 in an operating state, and even when the engine 1 is stopped. There are times when the vehicle travels electrically.

  Subsequently, the function of the starter 3 will be described with reference to FIGS. 2 and 3. FIG. 2 is a cross-sectional view showing starter 3 of the engine starting device according to Embodiment 1 of the present invention, and FIG. 3 is a configuration diagram showing one-way clutch 33 of starter 3 shown in FIG.

  The starter 3 is used at the time of cranking the engine 1. When a voltage is applied to the excitation terminal of the electromagnetic switch 32, the electrical contact of the electromagnetic switch 32 is closed and power is supplied to the motor unit of the starter 3. At the same time, the pinion 31 moves to the ring gear 13 side. Thereafter, when the ring gear 13 and the pinion 31 are engaged with each other, the rotational torque generated in the motor portion of the starter 3 is transmitted to the crankshaft 11 to drive the engine 1.

  The pinion moving body including the shaft 7 and the pinion 31 that is the output shaft of the motor unit is an angle at which the propion moving body generates a propulsive force from the stationary position toward the ring gear 13 when the motor unit is driven to rotate. Engage with a helical spline. Here, the pinion moving body has a one-way clutch 33 and a pinion 31 connected to an end of the one-way clutch 33.

  The one-way clutch 33 includes a cylindrical clutch outer 33a provided on the shaft 7, a cylindrical clutch inner 33b that is connected to the pinion 31 and rotates together with the pinion 31, and a clutch outer 33a and a clutch inner 33b. And a predetermined load that presses the roller 33c in the direction of the transmission position where the rotational torque is transmitted between the clutch inner 33b and the clutch outer 33a. And a spring 33d.

  Further, the one-way clutch 33 includes a plate-shaped annular clutch plate 33e that prevents the rollers 33c from being detached from between the clutch outer 33a and the clutch inner 33b, and a clutch cover 33f that holds the clutch plate 33e on the clutch outer 33a. And a space where the roller 33c and the spring 33d are disposed is filled with grease for reducing friction.

  In the one-way clutch 33, when the rotational speed of the ring gear 13 is higher than the rotational speed of the pinion 31 of the starter 3, the clutch inner 33b is driven by the ring gear 13 via the pinion 31.

  Further, when the rotational speed of the clutch inner 33b that rotates with the pinion 31 is higher than that of the clutch outer 33a that rotates with the shaft 7, the driving force from the ring gear 13 is applied to the motor unit that generates the rotational torque of the starter 3. However, each roller 33c moves in the direction of the non-transmission position while idling each spring 33d so as not to be transmitted via the clutch outer 33a and the shaft 7 and rotates idle.

  The force that deflects the spring 33d at this time is called idling torque, and when viewed from the ring gear 13, it becomes a load of rotational torque.

  Thereafter, when the rotational torque of the starter 3 becomes unnecessary on the engine 1 side, the application of the voltage at the excitation terminal is canceled. As a result, the state in which the pinion 31 is engaged with the ring gear 13 is eliminated, and the electrical contact of the electromagnetic switch 32 is opened, so that power supply to the motor portion of the starter 3 is lost.

  Next, in the engine starter according to Embodiment 1 of the present invention, a series of operations in an initial start in which the engine 1 is started by a driver's start operation will be described.

  When the start operation is performed by the driver, a voltage is applied to the excitation terminal of the electromagnetic switch 32 by a predetermined electrical signal, and the electromagnetic switch 32 is driven to close the electrical contact. As a result, when the motor circuit is energized, an electric current is supplied to the motor unit of the starter 3, and rotational torque is generated in the motor unit to start the starter 3.

  Further, by driving the electromagnetic switch 32, the pinion 31 moves to a position where it engages with the ring gear 13. As a result, the rotational torque of the motor unit is transmitted to the crankshaft 11 through the meshed pinion 31 and the ring gear 13, and the engine 1 is cranked. Thereafter, fuel injection is started.

  Further, when the start operation is performed by the driver, an activation electric signal is transmitted to the MG control circuit 22, and the MG control circuit 22 uses the power of the battery 4 to activate the generator motor 2 by powering. The power is supplied to the generator motor 2 via the power converter 21 that is used and controlled by the MG control circuit 22.

  As a result, the generator motor 2 is driven by power running and transmits the rotational torque to the crankshaft 11 via the belt 12 to crank the engine 1. That is, the generator motor 2 and the starter 3 are activated and crank the engine 1 in conjunction with an electric signal generated by the driver's starting operation.

  At this time, the activation electric signal may be transmitted during a period in which the driver is performing the starting operation, or any predetermined time has elapsed after the driver has completed the starting operation by the timer. It is good also as a transmission cut off at the time.

  Here, when it is decided that the electric signal is transmitted during the period in which the driver is performing the starting operation, when the engine 1 is determined to be started by the driver and the starting operation is stopped, When the electric signal disappears, the starter 3 is stopped. That is, the state in which the pinion 31 is meshed with the ring gear 13 is eliminated, and the electrical contact of the electromagnetic switch 32 is opened, so that power supply to the motor unit of the starter 3 is lost. At the same time, the power supply to the generator motor 2 by the MG control circuit 22 is stopped, and the power running is stopped.

  In addition, when the electric signal is transmitted by the timer after an arbitrary predetermined time has elapsed after the driver finishes the starting operation, the engine ECU 5 receives the crank angle signal from the crank angle sensor. Based on the current crank angle obtained by the above and the cycle of the crank angle signal, the rotational speed of the engine 1, that is, the rotational speed of the ring gear 13 is calculated and monitored.

  Further, the engine ECU 5 determines whether or not the engine 1 has reached a predetermined rotation speed or more based on the rotation speed of the engine 1 and the engine 1 has completely exploded, that is, the engine 1 is in an operating state and started. It is determined whether or not it has been completed. If the engine 1 is not completely exploded, the engine ECU 5 stands by while maintaining the state until the determination of the complete explosion of the engine 1 is made.

  On the other hand, as a result of the determination, when the engine 1 is completely exploded, the engine ECU 5 stops the starter 3. That is, the state in which the pinion 31 is meshed with the ring gear 13 is eliminated, and the electrical contact of the electromagnetic switch 32 is opened, so that power supply to the motor unit of the starter 3 is lost. At the same time, the engine ECU 5 stops the power supply to the generator motor 2 by the MG control circuit 22 and stops the power running.

  With these series of operations, in the initial start in which the engine 1 is started by the start operation of the driver, the engine 1 is cranked together with both the generator motor 2 and the starter 3, and the process for starting the engine 1 is completed.

  Next, a series of operations in restarting the engine 1 in the engine starter according to Embodiment 1 of the present invention will be described.

  When the fuel supply to the engine 1 is stopped by the engine automatic stop / restart control and then the restart condition is satisfied, the engine ECU 5 transmits an electric signal for starting to the MG control circuit 22. The MG control circuit 22 that has received the activation electrical signal uses the power of the battery 4 and supplies power to the generator motor 2 via the power converter 21. As a result, the generator motor 2 is driven by power running and transmits the rotational torque to the crankshaft 11 via the belt 12 to crank the engine 1.

  During the cranking of the engine 1, the engine ECU 5 determines the rotational speed of the engine 1, that is, the ring gear 13 based on the current crank angle obtained from the crank angle signal from the crank angle sensor and the cycle of the crank angle signal. The rotation speed is calculated and monitored.

  At this time, the engine ECU 5 starts based on the rotational speed of the engine 1 to determine whether or not the rotational speed of the engine 1 is equal to or higher than a predetermined rotational speed and the engine 1 has completely exploded, that is, the engine 1 is in an operating state and started. It is determined whether or not is completed. If the engine 1 is not completely exploded, the engine ECU 5 stands by while maintaining the state until the determination of the complete explosion of the engine 1 is made.

  On the other hand, as a result of the determination, when the engine 1 is completely exploded, the engine ECU 5 stops the power supply to the generator motor 2 by the MG control circuit 22 and stops the power running.

  By the series of operations, when the engine 1 is restarted, the process of cranking the engine 1 with the generator motor 2 and starting the engine 1 is completed.

  According to the engine starter configured as described above, in the initial start in which the driver performs the start operation, only the combined cranking using both the generator motor 2 and the starter 3 is performed, and the restart after the automatic engine stop is performed. At the start, only cranking with the generator motor 2 is performed.

  That is, by not selecting the starting method before the initial starting of the engine 1 and the restarting of the engine 1, a complicated control for selecting the starting method and a sensor as a judgment material are not required, and the low Engine startability can be ensured at a low cost.

  In addition, in the initial start of the engine 1 at a low temperature when the belt 12 is slippery, the combined cranking using both the generator motor 2 and the starter 3 is performed, and the engine 1 is cranked only by the generator motor 2 is warm. The engine startability can be ensured only by restarting the engine 1 that is in the machine state and in which the belt 12 is difficult to slip.

  Further, since the driving force at the time of starting is fixed in the initial starting of the engine 1 and the restarting of the engine 1, a sense of incongruity to the driver and passengers is reduced. Furthermore, since only the generator motor 2 is restarted when the engine 1 is restarted, complicated control becomes unnecessary, and the engine 1 can be restarted quickly.

As described above, according to the first embodiment, in the initial start in which the engine 1 is started by the driver's start operation, the engine 1 is cranked together by both the generator motor 2 and the starter 3, and the engine 1 is restarted. Then, the engine 1 is cranked by the generator motor 2.
Therefore, by unifying the usage methods of the generator motor 2 and the starter 3 when starting the engine, it is possible to ensure engine startability with a simple configuration and low cost.

Embodiment 2. FIG.
In the second embodiment of the present invention, the function of the one-way clutch 33 of the starter 3 will be described.

  In the first embodiment described above, in the combined cranking, the generator motor 2 and the starter 3 crank the engine 1 at the same time, but each cylinder of the engine 1 performs the steps of intake → compression → expansion → exhaust. Repeatedly, the load increases in the compression process and decreases in the expansion stroke. Therefore, a pulsation in which the cranking rotation speed repeatedly decreases and increases occurs.

  Further, in the generator motor 2 connected to the crankshaft 11 by the belt 12, the reduction ratio between the output shaft of the generator motor 2 and the crankshaft 11 of the engine 1 is about 2 to 3. The starter 3 that is detachably connected by a gear has a reduction mechanism with a reduction ratio of about 4 to 6 inside the starter 3, and the reduction ratio between the pinion 31 that is the output shaft and the crankshaft 11 is about Since it is set at about 10, the reduction ratio between the motor part of the starter 3 and the crankshaft 11 is about 40-60. Therefore, the generator motor 2 is advantageous in that rotation at a high rotation is advantageous as compared to the starter 3, but torque at a low rotation is disadvantageous.

  Since the generator motor 2 and the starter 3 are configured as described above, in the cranking region where the load of the compression process is large, the proportion depending on the output torque of the starter 3 is large, and the cranking region where the load of the expansion stroke is small. Then, the ratio depending on the output torque of the generator motor 2 may increase.

  In particular, when there is a margin in the output torque of the generator motor 2 in the cranking region where the load of the expansion stroke is small, the one-way clutch 33 is used when the cranking rotational speed exceeds the no-load rotational speed of the starter 3. Runs idle, and the starter 3 does not contribute to the cranking at all.

  At this time, the idling torque necessary for idling the one-way clutch 33 becomes a load on the generator motor 2 that rotates the ring gear 13 via the belt 12 as described above.

  Further, when the output torque of the generator motor 2 has a margin, the cranking rotation speed increases in the cranking region where the load of the expansion stroke is small, and the torque of the output torque of the generator motor 2 is insufficient in the next compression process. Therefore, the cranking rotational speed is reduced to a value below the no-load rotational speed of the starter 3. For this reason, the cranking rotation speed repeatedly increases and decreases, and this increase and decrease makes the belt 12 slip easily beyond the transmission capacity of the belt 12.

  Even when the engine 1 is cranked using only the conventional starter 3, the cranking rotational speed increases in the cranking region where the load of the expansion stroke is small and exceeds the no-load rotational speed of the starter 3. However, in the combined cranking, the generator motor 2 further increases the cranking rotation speed.

  Therefore, the idling torque of the one-way clutch 33 of the starter 3 according to the second embodiment of the present invention is more than the idling torque that can suppress the acceleration of the cranking rotational speed to be increased and lowered to the extent that the belt 12 does not slip. Is set.

  That is, the idling torque generated by the load of the spring 33d can appropriately reduce the rotational speed on the high rotation side of the cranking pulsation, and can moderate the acceleration of the cranking speed increase and decrease. The load of the spring 33d is set.

  At this time, in the rotation speed region on the low rotation side of the cranking pulsation, the output torque of the generator motor 2 becomes insufficient, so the starter 3 transmits the output torque to the ring gear 13 and no idling torque is generated. There is no effect on the rotation speed.

  In other words, since only the cranking pulsation speed on the high speed side of the cranking pulsation can be reduced, the cranking pulsation amplitude is suppressed and the cranking speed on the high speed side is reduced. Since the rotation speed is decreased and the period is extended, the acceleration of the cranking rotation speed can be moderated.

  Here, the torque value of the idling torque may be set in accordance with the environment in which the combined cranking is performed. For example, the idling torque may be set to a high rotation speed at which the belt 12 does not slip at −30 ° C. For example, the combined cranking can be performed even when the engine is started at a low temperature.

  However, when the torque value of the idling torque is set at a low temperature at which the belt 12 is slippery, the load of the spring 33d becomes higher and the idling torque becomes higher than in the conventional case, so that the belt 12 is difficult to slip in a warm-up state or the like. In a high temperature state, the slippage of the belt 12 is cranked with an idling torque more than necessary. However, even in this state, since the temperature of the engine 1 is high and the friction torque necessary for cranking is small, the engine 1 can be started without any problem.

  Here, by using a material having high temperature dependency for the spring 33d, the torque value of the idling torque may be increased at a low temperature. For example, it is conceivable to use an elastic member made of an elastic material such as resin or rubber and hardened at a low temperature. In this case, since the idling torque becomes high at a low temperature, the slip of the belt 12 is suppressed, and in a high temperature state where the belt 12 is difficult to slip, the idling torque does not become unnecessarily large, so the startability can be improved.

  Further, in order to reduce the rotational speed on the high rotation side of the cranking pulsation, the viscosity of the grease may be used, and the torque value of the idling torque can be increased by the viscosity of the grease.

  Specifically, by actively using the viscosity of grease that normally increases in viscosity at low temperatures and decreases in viscosity at high temperatures, the idling torque increases at low temperatures, and the idling torque decreases at high temperatures. It is possible to perform idling torque suitable for the temperature environment against slipping. Furthermore, by combining with the load of the spring 33d described above, the degree of freedom in setting the idling torque can be improved.

  According to the starter 3 configured in this manner, the starter 3 transmits torque to the ring gear 13 on the low rotation side due to pulsation during cranking of the engine 1, and no idling torque of the one-way clutch 33 is generated. Street rotation speed is obtained.

  Further, when the starter 3 does not transmit torque to the ring gear 13 on the high rotation side of the cranking pulsation, the idling torque of the one-way clutch 33 is applied to the generator motor 2 due to the load of the spring 33d and the viscosity of the grease. On the other hand, it becomes a load. As a result, an increase in the rotational speed is suppressed, so that a change in rotational speed during cranking, that is, a situation where the belt 12 is slippery, that is, an acceleration / deceleration gradient can be moderated, and the belt 12 is prevented from slipping. be able to.

  For this reason, there is no need to select a starting method before starting the engine 1 in consideration of slipping of the belt 12, and a complicated control and a sensor that is a judgment material for selecting the starting method are not required. Further, even when the combined cranking using both the generator motor 2 and the starter 3 is performed at a low temperature at which the belt 12 is slippery, the engine 1 can be cranked with the belt 12 not slipping more. Engine startability can be ensured at a low cost.

Embodiment 3 FIG.
In the second embodiment, the method of adjusting the idling torque of the one-way clutch 33 in order to suppress the rotational speed on the high rotation side of the cranking pulsation has been described. However, in the third embodiment of the present invention, the embodiment is described. In order to obtain the same effect as 2, a method for reducing the output torque of the generator motor 2 will be described.

  The configuration in Embodiment 3 and the series of operations related to engine start are the same as those in Embodiment 1 above. Further, the combined cranking according to Embodiment 3 of the present invention is characterized in that cranking is performed by reducing the output torque of the generator motor 2 from the beginning.

  In conventional engine starting, an extremely low temperature such as −30 ° C. can be considered, but in order to start in a short time, there is little restriction on the output, and cranking is performed at the rated output or the maximum output. Many.

  In the third embodiment of the present invention, the output torque of the generator motor 2 is deliberately reduced in order to take advantage of the characteristics of both the starter 3 advantageous for low rotational torque and the generator motor 2 advantageous for high rotational torque. . Here, according to the cranking pulsation, the output torque of the rated output or the maximum output may be output on the low rotation side and the output torque may be reduced on the high rotation side, but the output torque of the generator motor 2 may be reduced from the initial stage. By reducing it, an engine starter with simple motor control of the generator motor 2 can be obtained.

  According to the engine starter configured as described above, the starter 3 transmits torque to the ring gear 13 on the low rotation side due to the pulsation during cranking of the engine 1, and the idling torque of the one-way clutch 33 is not generated. A rotation speed close to the conventional one can be obtained.

  In addition, when the starter 3 does not transmit torque to the ring gear 13 on the high rotation side of the cranking pulsation, the increase in the rotational speed is suppressed by the amount that the output torque of the generator motor 2 is reduced. The change in the rotational speed during cranking, that is, the state in which the belt 12 is slippery, that is, the acceleration / deceleration gradient can be made gentle, and the slip of the belt 12 can be suppressed.

  Therefore, there is no need to select a starting method before starting the engine 1 in consideration of slipping of the belt 12, and a complicated control or a sensor for determining the starting method is not required. Further, even when the combined cranking using both the generator motor 2 and the starter 3 is performed at a low temperature at which the belt 12 is slippery, the engine 1 can be cranked with the belt 12 not slipping more. Engine startability can be ensured at a low cost.

  Here, the setting and grease of the spring 33d of the one-way clutch 33 shown in the second embodiment may be combined with the method for reducing the output torque of the generator motor 2 shown in the third embodiment. In this case, the change in rotational speed during cranking, which is a situation where the belt 12 is slippery, that is, the acceleration / deceleration gradient can be set so as to be more gradual.

  At this time, the method shown in the second and third embodiments is a method that controls the output torque of the generator motor 2 in accordance with the tensioner that can adjust the tension of the belt 12 or the cranking pulsation. And may be combined.

  In the first to third embodiments, if an electric start signal is transmitted to the generator motor 2 and the starter 3 at the same time, the engine start system is not complicated, and complicated start control is not required. An engine starter can be obtained.

  Here, if the rotation start of the generator motor 2 is accelerated when the electrical signals are transmitted simultaneously, the operation of the starter 3 is performed after the mechanically stable time has elapsed, so the MG control circuit 22 Thus, it is possible to incorporate control for starting the rotation of the generator motor 2 after a predetermined time has elapsed.

  Further, if the timing for transmitting the electric signal to the generator motor 2 and the starter 3 can be made simultaneously, the voltage applied to the electromagnetic switch 32 of the starter 3 can be used as the electric signal even in the initial start of starting the engine 1 by the driver's starting operation. By transmitting to the MG control circuit 22 without passing through other control functions, the combined cranking can be performed.

  Further, a tooth chamfered portion is provided as a curved surface shape along the tooth surface between the end surface on the ring gear 13 side of the pinion 31 and the tooth surface on the non-torque transmission side, and the tooth tip outer diameter portion of the pinion 31 is further provided. The mechanism may be provided with a chamfered portion of the tooth tip along the outer diameter of the tooth tip. In this case, since the tooth chamfered portion is formed by a curved surface along the tooth surface on the non-torque transmission side, when viewed in a cross section perpendicular to the axial direction, the teeth of the ring gear 13 and the teeth of the pinion 31 are Is always the same as the engaged state.

  When the teeth are not the same as the meshed state, the tooth speed vectors of the ring gear 13 and the pinion 31 are different. As a result, the contact position swings in the axial direction, and not only a stable rotational force cannot be transmitted, but also a repelling force may occur, resulting in an unstable meshing state.

  That is, by providing a tooth chamfered portion as a curved surface shape along the tooth surface between the ring gear 13 side end surface of the pinion 31 and the tooth surface on the non-torque transmission side, the generator motor 2 starts rotating first. However, stable meshing is possible.

  In the first to third embodiments, the generator motor 2 is always connected to the crankshaft 11 of the engine 1 by the belt 12 and has been described as the generator motor 2 having the functions of regeneration and power running. As long as it is connected to the crankshaft 11, the same effect can be obtained even in other forms. The same effect can be obtained even with an electric motor having no regeneration function.

  1 engine, 2 generator motor, 3 starter, 4 battery, 5 engine control device (engine ECU), 11 crankshaft, 12 belt, 13 ring gear, 21 power converter, 22 generator motor control circuit (MG control circuit), 31 pinion 32, electromagnetic switch, 33 one-way clutch, 33a clutch outer, 33b clutch inner, 33c roller, 33d spring, 33e clutch plate, 33f clutch cover.

Claims (3)

An engine starter mounted on a vehicle that performs engine automatic stop / restart control for automatically stopping the engine when an engine stop condition is satisfied and then restarting the engine when a restart condition is satisfied,
A generator motor coupled to the crankshaft of the engine;
A starter that meshes a pinion with a ring gear provided on the crankshaft when the engine is started,
In the initial start to start the engine by the start operation of the driver, the engine is combined with both the generator motor and the starter,
An engine starter that cranks the engine with the generator motor when restarting the engine. The engine starter according to claim 1, wherein, in the combined cranking, the generator motor cranks the engine at an output smaller than a rated output or a maximum output. The starter is
A motor unit that generates rotational torque;
An output shaft that is rotated by rotational torque generated in the motor unit;
A pinion provided on the output shaft so as to be movable in the axial direction, and meshed with a ring gear provided on the crankshaft when starting the engine;
Provided between the output shaft and the pinion, and when the rotational speed on the output shaft side is faster than the rotational speed on the pinion side, the rotational torque generated in the motor unit is transmitted to the pinion, A one-way clutch that is rotationally driven from the ring gear, and in which the pinion side rotational speed is higher than the output shaft side rotational speed to generate an idling torque and enter an idle state,
The engine starting device according to claim 1 or 2, wherein in the one-way clutch, an idling torque at a low temperature is larger than an idling torque at a high temperature.

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