JP3951138B2 - Hybrid vehicle power unit and hybrid vehicle - Google Patents

Description

  The present invention relates to a hybrid vehicle including an engine and a motor as a driving source for traveling and a power device for the hybrid vehicle.

There has been implemented a hybrid vehicle that includes an engine and a motor as a travel drive source and travels by switching the drive source according to the travel state (see, for example, Patent Document 1).
In the hybrid vehicle described in Patent Document 1, an output shaft of a motor is connected to a counter drive gear connected to a front wheel of the vehicle via an automatic transmission, and an output shaft of an engine including a generator is clutched. The power unit is configured by connecting to the counter drive gear via the. The hybrid vehicle during normal driving is operated at the best fuel consumption rate after the engine is disconnected from the front wheel side by clutch disconnection, and the motor is driven by the electric power generated by the generator.

Also, when high output is required or when the motor breaks down, etc., a clutch is connected, and by adding the driving force of the engine to the driving force of the motor, quick acceleration according to the required driving force can be realized, Instead of the motor, the front wheels are driven by the engine to continue running.
Japanese Unexamined Patent Publication No. 7-96759 (FIG. 1)

However, in the hybrid vehicle power unit disclosed in Patent Document 1, the engine and the motor are merely provided with the counter drive gear interposed, as is apparent from FIG. It takes space.
In addition, the overall configuration of the hybrid vehicle power unit is such that the engine is provided independently for the power transmission path from the motor to the front wheels, and the driving force of the engine is driven by a counter via a clutch as necessary. It can be regarded as transmitting to a gear (part of the power transmission path). Therefore, providing a member such as a clutch or clutch actuator for transmitting the engine driving force complicates the structure, and also requires a considerable space for installing a large-capacity clutch capable of transmitting the engine driving force. Therefore, there is a problem in that it is further disadvantageous in terms of the space efficiency.

  An object of the present invention is to provide a hybrid vehicle and a hybrid vehicle that can arbitrarily transmit two kinds of driving forces of an engine and a motor to driving wheels, can reduce manufacturing costs with a simple configuration, and can improve space efficiency. It is to provide a power unit.

To achieve the above object, a first aspect of the invention, at least one of the front and rear wheels as driven wheels, via the driving force and the differential mechanism of the motor mechanism engine of any driving force to left and right driving wheels In a hybrid vehicle that is driven by transmission, an outer shaft that is disposed between the differential mechanism and the left and right drive wheels, and is connected to either the differential mechanism side or the drive wheel side, and disposed in the outer shaft An inner shaft that is connected to the other of the differential mechanism side or the drive wheel side, a motor mechanism is provided between the outer shaft and the motor mechanism, and a torque in a relative rotational direction is applied to the outer shaft by the motor mechanism, and a motor mechanism In contrast, a power supply means for supplying electric power from the vehicle body side and a relative rotation restricting means for restricting the relative rotation of the outer shaft and the inner shaft are provided.

Therefore, when the outer shaft and the inner shaft are provided between the differential mechanism and the left and right drive wheels, and the relative rotation is restricted by the relative rotation restricting means, the outer shaft and the inner shaft function as one drive shaft. The driving force of the engine is transmitted to the driving wheel side, and the vehicle travels by driving the engine. On the other hand, when the motor mechanism is actuated by supplying power from the vehicle body side by the power feeding means, the driving force of the motor mechanism is driven to the driving wheel side. The vehicle is driven by the engine and motor drive while being transmitted to the driving wheel side along with the driving force of the engine while rotating the shaft connected to the motor.

As described above, since the motor mechanism is provided between the outer shaft and the inner shaft that function as a drive shaft between the differential mechanism and the left and right drive wheels, the installation space for the motor mechanism itself is not necessary, and the vehicle space efficiency is improved. improves. In addition, the driving force from the engine is transmitted to the driving wheel side without being obstructed by the motor mechanism, while the driving force generated by the motor mechanism is transmitted to the driving wheel side without any trouble. As a result, a member such as a clutch or a clutch actuator for connecting the motor mechanism to the power transmission mechanism from the engine of the vehicle to the driving wheel is not required, the configuration is simplified, and the installation of the clutch or the actuator is simplified. Space is not required.
Moreover, since the left and right drive wheels are provided with motor mechanisms, for example, if the driving force on the drive wheels of the motor mechanism outside the turn is increased when sudden steering is performed, The yaw moment can be applied to improve the turning ability, and if the driving force on the driving wheels of the motor mechanism on the inner side of the turn is increased when the posture of the vehicle becomes unstable during turning, The yaw moment can be applied and stabilized, and thus the turning control using the left and right motor mechanisms can be executed.

According to a second aspect of the present invention, in the first aspect of the present invention, the lock mechanism for fixing the shaft connected to the differential mechanism side is provided.
Therefore, when the motor mechanism is operated in a state where the shaft on the differential mechanism side is locked by the lock mechanism, the driving force of the motor mechanism is transmitted to the driving wheel side and the vehicle travels by driving the motor.

As a preferred aspect of claims 1 and 2 , a four-wheel drive hybrid vehicle that drives the front wheels by the engine and distributes the driving force of the engine to the rear wheels is driven by the engine and the motor mechanism with the rear wheels as drive wheels. It is desirable to make it so. In this case, even if the motor mechanism fails, the driving force of the engine can be distributed to the rear wheels and the four-wheel drive running can be continued.

According to hybrid vehicle of the invention of claim 1 as described above, it can be arbitrarily transmitted to the driving wheels the two drive force of the engine and the motor mechanism, and, the manufacturing cost can be reduced with a simple structure In addition, the space efficiency can be improved , and the turning performance of the vehicle can be improved by executing the turning control using the left and right motor mechanisms .

Hereinafter, an embodiment in which the present invention is embodied in a 4WD type hybrid vehicle will be described.
FIG. 1 is an overall configuration diagram showing a hybrid vehicle according to the present embodiment. An engine 1 is disposed horizontally as a driving source for driving at the front of the vehicle, and an output gear 2a of an automatic transmission 2 connected to the engine 1 is provided. Is engaged with a ring gear 3a of a front differential 3 (hereinafter referred to as a front differential). A pair of side gears 3d that mesh with the pinion gear 3c in the differential case 3b of the front differential 3 are connected to the left and right front wheels 5a via the drive shaft 4, respectively, and the driving force from the engine 1 is transmitted to the front wheels 5a via the front differential 3a. Is done.

A ring gear 6a of a power take-off unit 6 (hereinafter referred to as PTU) is connected to the differential case 3b of the front differential 3, and a pinion gear 7a provided at the front end of the front propeller shaft 7 is engaged with the ring gear 6a. . The automatic transmission 2, the front differential 3, and the PTU 6 are assembled in a common housing 8.
The rear end of the front propeller shaft 7 is connected to the front end of the rear propeller shaft 10 via the electromagnetic clutch 9a of the electronic control coupling 9, and the pinion gear 10a provided at the rear end of the rear propeller shaft 10 is connected to the rear differential 11 ( difference). a mechanism, hereinafter, and the ring gear 11a and meshing) of the rear differential. The rear differentials 11 are connected to the left and right rear wheels 5b (drive wheels) via drive shafts 12, respectively. The electronic control coupling 9 and the rear differential 11 are assembled in a common housing 13.

  The power transmitted from the front propeller shaft 7 side to the rear propeller shaft 10 side is adjusted according to the engagement force of the electromagnetic clutch 9a of the electronic control coupling 9, and as a result, distributed to the rear wheel 5b side via the PTU 6. The driving force of the engine 1 changes. By the action of the electronic control coupling 9, the distribution of the engine driving force to the front wheel 5a and the rear wheel 5b of the vehicle can be arbitrarily adjusted, for example, between 100: 0 to 50:50.

In the present embodiment, the left and right drive shafts 12 of the rear differential 11 function as a driving source for traveling as a motor. 2 is a cross-sectional view taken along the line II-II of FIG. 1 showing the internal structure of the left drive shaft 12, and the configuration around the left drive shaft 12 will be described with reference to FIG. Is the same configuration with left-right symmetry.
The right end of the differential side shaft 21 is connected to the side gear 11d that meshes with the pinion gear 11c in the differential case 11b of the rear differential 11, and the differential side shaft 21 is rotatably supported by a bearing 22 provided in the housing 13 of the rear differential 11. Has been. The left end of the differential shaft 21 protrudes outside the housing 13 and is connected to the right end of the outer shaft 24 via a joint portion 23. The outer shaft 24 has a cylindrical shape, and an inner shaft 25 is disposed inside the outer shaft 24 so as to have the same axial center. Both ends of the inner shaft 25 are rotatably supported by bearings 26 provided on the outer shaft 24.

  The left end of the inner shaft 25 protrudes outward from the outer shaft 24 and is connected to the right end of the hub side shaft 28 via a joint portion 27. The hub side shaft 28 is rotatably supported by a bearing 30 with respect to the shaft support portion 29. Has been. A hub 31 having a disc brake 34 is connected to the left end of the hub side shaft 28 so as to protrude leftward from the shaft support portion 29, and the rear wheel 5 a is fixed to the hub 31 via a wheel bolt (not shown). The ends of the upper arm 32 and the lower arm 33 of the suspension mechanism are connected to the shaft support portion 29, and both the arms 32 and 33 are swung while the joint portions 23 and 27 are bent to allow the rear wheel 5b to move up and down.

  A rotor 41 is provided on the outer periphery of the inner shaft 25, and the rotor 41 is formed of a large number of rotor cores made of permanent magnets arranged around the axis of the inner shaft 25. An annular stator 42 is press-fitted and fixed to the inner circumference of the outer shaft 24. Although not shown, the stator 42 has a large number of bobbins each having a coil wound around an annular stator core in which electromagnetic steel plates are laminated. It is formed in a row. The rotor 41 and the stator 42 are opposed to each other with a predetermined distance between the inner and outer circumferences and extend over the entire axial direction in the outer shaft 24. The rotor 41 and the stator 42 constitute a motor generator 43 (motor mechanism). Has been.

  Although not shown, the bobbins of the stator 42 are separated into three phases of U, V, and W and are alternately arranged, and bobbin coils are bound for each phase. The coils of each phase are connected via an electric wire 44 embedded in the outer shaft 24, a flexible electric wire 45 arranged around the joint portion 23, and an electric wire 46 embedded in the differential shaft 21. In the housing 13 of the rear differential 11, the three slip rings 47 formed on the outer peripheral surface of the differential shaft 21 are electrically connected to each other. Each slip ring 47 is in contact with a brush 48, and each brush 48 is connected to an inverter 49.

  The inverter 49 is connected to the traveling battery 50, and executes power running control for causing the motor generator 43 to function as a motor and regenerative control for causing the motor generator 43 to function as a generator by using electric power supplied from the battery 50. In the power running control, the inverter 49 sequentially energizes the coils of each phase via the brush 48, the slip ring 47, and the electric wires 44 to 46 according to the rotation angle of the rotor 41 (power feeding means), and the rotor is generated by the magnetic field generated in the stator core. A rotational force is applied to 41 to drive the rear wheel 5b to rotate. In addition, the inverter 41 during regenerative control converts the regenerative power generated in the coil into electric wires 44 to 46, slip rings when the rotor 41 is driven from the rear wheel 5b side due to traveling by engine driving, vehicle deceleration or the like. 47. The battery 50 for traveling is charged via the brush 48.

Further, the inverter 41 has a function of short-circuiting the U, V, and W phases of the stator 42. When each phase is short-circuited, relative rotation between the stator 42 and the rotor 41, that is, the outer shaft 24 and the inner shaft 25. Relative rotation is regulated (relative rotation regulating means).
A lock gear 51 is formed integrally with the differential shaft 21 adjacent to the slip ring 47, and a lock claw 53 is supported at a lower position of the lock gear 51 from the inner wall of the housing 13 via a solenoid 52. With the excitation of the solenoid 52, the lock claw 53 protrudes upward and can be engaged with the lock gear 51. The lock gear 51, the solenoid 52, and the lock claw 53 constitute a lock mechanism 54 (lock means).

  On the other hand, an HV-4WD ECU 61 is installed in the interior of the vehicle, and the HV-4WD ECU 61 is a storage device (ROM, RAM, etc.) for storing an input / output device (not shown), a control program, a control map, and the like. ), A central processing unit (CPU), a timer counter, and the like. On the input side of the ECU 61 for EV-4WD, an accelerator sensor 62 for detecting the accelerator opening θacc, a wheel speed sensor 63 for detecting the wheel speed VH of the front and rear wheels 5a and 5b, and a throttle sensor and a rotational speed sensor (not shown) of the engine. Various sensors such as are connected. Further, on the output side of the EV-4WD ECU 61, there are various devices such as the electromagnetic clutch 9a of the electronic control coupling 9, the inverter 49, the solenoid 52 of the lock mechanism 54, and a throttle actuator and a fuel injection valve (not shown) of the engine 1. Is connected.

  In the hybrid vehicle of the present embodiment, the front wheel 5a is basically driven by the engine 1 by adjusting the distribution of the engine driving force to the front wheels 5a and the rear wheels 5b to 100: 0 by the electronic control coupling 9, and the rear wheels 5b is driven by the motor generator 43, and the HV-4WD ECU 61 performs drive control (HV control) of the engine 1 and the motor generator 43 based on various conditions such as the driver's required driving force and the SOC of the battery 50, The driving force distribution control (4WD control) of the front and rear wheels 5a and 5b of the vehicle is integratedly performed.

  For example, in the HV control, the driver's required driving force is calculated from a preset map based on the accelerator opening θacc and the vehicle speed obtained from the wheel speed VH. On the other hand, in the 4WD control, slip suppression and turning due to sudden acceleration are calculated. Distributing the driving force of the front and rear wheels 5a, 5b in accordance with the vehicle running state for the purpose of suppressing oversteer and understeering at the time (including not only the distribution of the engine driving force by the electronic control coupling 9 but also the driving force of the motor generator 43) The driving force distribution between the front and rear wheels 5a and 5b) is calculated, and the engine 1 on the front wheel 5a side and the motor on the rear wheel 5b side so as to satisfy these required driving forces and the driving force distribution of the front and rear wheels 5a and 5b. The driving force of the generator 43 is determined, and the engine 1 and the motor generator 43 are controlled to achieve each driving force.

Further, when the driving force of the motor generator 43 is insufficient with respect to the driving force determined from the required driving force and the driving force distribution of the front and rear wheels 5a and 5b, the engaging force of the electromagnetic clutch 9a of the electronic control coupling 9 is adjusted. Then, the driving force of the engine 1 is distributed to the rear wheel 5b side to compensate for the shortage.
In addition, the driving force of the motor generator 43 is also used for turning control of the vehicle. For example, the HV-4WD ECU 61 increases the driving force for the rear wheel 5b of the motor generator 43 outside the turning when the sudden steering is performed. Thus, the yaw moment in the oversteer direction is applied to the vehicle to improve the turning ability, and when the vehicle becomes unstable during turning, the driving force of the motor generator 43 inside the turning is increased, thereby Is stabilized by applying a yaw moment in the direction of understeer.

  On the other hand, the ECU for HV-4WD 61 sequentially calculates the SOC (charge level) by integrating the input / output currents of the traveling battery 50 detected by a current sensor (not shown), and when the SOC falls below a predetermined value, the rear wheel 5b is stopped by the motor generator 43, and the engine driving force is distributed to the rear wheels 5b via the electronic control coupling 9 to replace the motor generator 43, while the motor generator 43 is appropriately generated by regenerative control. And the battery 50 is charged. The regenerative control is also appropriately performed when the rotor 41 of the motor generator 43 is driven from the rear wheel 5b side as the vehicle decelerates. Further, when the motor generator 43 fails as well as the SOC decreases, the engine driving force is distributed to the rear wheel 5b side to replace the motor generator 43.

  The embodiments of the HV control and the 4WD control are not limited to those described above, and can be variously changed. For example, the vehicle is basically driven by the rear wheel drive by the motor generator 43, and the driving force of the motor generator 43 is insufficient. Sometimes the engine 1 may drive the front wheels 5a or the front and rear wheels 5a, 5b to compensate for the shortage, or the engine 1 basically drives the front wheels 5a, 5b and the driving force of the rear wheels 5b is insufficient. In doing so, the rear portion 5b may be driven by the motor generator 43 to compensate for the shortage.

As described above, the rear wheel 5a is normally driven by the motor generator 43 alone, and is driven by the engine 1 alone when the SOC of the battery 50 is lowered or the motor generator 43 fails, and when the driving power of the motor generator 43 is insufficient, The generator 43 and the engine 1 are used in combination and will be described in detail below.
First, when the motor generator 43 is driven alone, the HV-4WD ECU 61 excites the left and right solenoids 52 to engage the lock claws 53 with the lock gear 51, and then the motor generator by the inverter 49 while the engine 1 is stopped and held. 43 power running control is started. Since the outer shaft 24 together with the left and right differential shafts 21 is restricted from rotating with respect to the housing 13 of the rear differential 11 by the engagement of the lock pawls 53 with the lock gear 51, the magnetic field of the stator 42 of the outer shaft 24 directly It acts in the direction in which the rotor 41 is rotated, and is transmitted as a driving force from the inner shaft 25 to the rear wheel 5b via the hub side shaft 28.

  Further, when switching from the drive of the motor generator 43 alone to the drive of the engine 1 alone, the HV-4WD ECU 61 demagnetizes the left and right solenoids 52 to release the engagement of the lock claws 53, and then performs power running control on the motor generator 43. And the inverter 49 causes the U, V, and W phases of the stator 42 to be short-circuited. Since the engine driving force distributed to the rear wheel 5b via the PTU 6 is input to the rear differential 11 and the relative rotation between the outer shaft 24 and the inner shaft 25 is restricted by the short circuit of the stator 42, the drive shaft 12 is normally Functions as a single drive shaft and transmits engine driving force from the rear differential 11 to the rear wheel 5b.

  Further, at the time of switching from the driving of the engine 1 alone to the combined driving of the motor generator 43 and the engine 1, the HV-4WD ECU 61 stops the short circuit of the stator 42 and starts the power running control of the motor generator 43 by the inverter 49. . As in the case of the engine 1 alone, the drive shaft 12 transmits an engine driving force and simultaneously functions as a motor to generate a driving force. The driving force of the engine 1 and the motor generator 43 is transmitted to the rear wheel 5b. Is done.

  As described above, in the 4WD type hybrid vehicle of the present embodiment, the power device for the rear wheel 5b is configured so that the two types of driving forces of the engine 1 and the motor generator 43 can be arbitrarily transmitted to the rear wheel 5b. The driving of the front wheel 5a by the motor generator 43 and the driving of the rear wheel 5b by the motor generator 43 are basically used, and the shortage of the driving force of the motor generator 43 with respect to the rear wheel 5b is compensated by the engine driving force, or the left and right motor generators 43 are used. Turning control can be performed, so that the running state of the vehicle can always be appropriately controlled. In addition, when driving by the motor generator 43 becomes impossible due to a decrease in the SOC of the battery 50 or a failure of the motor generator 43, the engine driving force is distributed to the rear wheels 5b and replaced with the motor generator 43. Four-wheel drive traveling can be continued.

  Since the motor generator 43 that is one of the drive sources is incorporated in the drive shaft 12, the installation space for the motor generator 43 is not required at all because the drive shaft 12 itself is slightly thicker than a normal one. Therefore, for example, it is possible to prevent problems such as the motor generator 43 being installed in the engine room and squeezing the engine 1, the automatic transmission 2, etc., thereby improving the space efficiency of the vehicle and expanding the vehicle compartment. Can be used effectively.

  Further, a motor generator 43 is incorporated in the drive shaft 12 which is a part of the power transmission path from the engine 1 to the rear wheel 5b, and the outer shaft 24 (stator 42) is connected to the engine 1 side, and the inner shaft 25 (rotor 41) is connected to the rear wheel 5b, so that the driving force from the engine 1 is transmitted to the rear wheel 5b without being obstructed by the motor generator 43, while the motor generator 43 is generated during power running control. The driving force is naturally transmitted to the rear wheel 5b side, and the driving force from the rear wheel 5b side during regenerative control is naturally transmitted to the motor generator 43, so that the functions as a motor and a generator can be achieved without hindrance.

  That is, when the system configuration similar to that of the hybrid vehicle power device disclosed in Patent Document 1 is adopted, the motor generator 43 is connected to a part of the power transmission path from the engine 1 to the rear wheel 5b via the clutch. Therefore, members such as a clutch and an actuator for the clutch are required, but in the present embodiment, these members are not necessary, so that the configuration of the power device for the rear wheel 5b can be greatly simplified, and the clutch, the actuator, etc. The space efficiency of the vehicle can be further improved by the installation space.

  In this embodiment, a lock mechanism 54 that restricts the rotation of the differential shaft 21 is necessary in place of the clutch and the actuator disclosed in Patent Document 1. The lock mechanism 54 restricts the rotation of the differential shaft 21 by a lock claw 53. Therefore, even if the lock mechanism 54 is installed, there is no possibility that the effects of simplification of the configuration and improvement in space efficiency are impaired.

  This is the end of the description of the embodiment, but the aspect of the present invention is not limited to this embodiment. For example, in the above embodiment, the power device of the 4WD type hybrid vehicle is embodied, but the type of the vehicle to be applied is not limited to this, and the front wheel is driven by the engine 1 and the motor generator 43 as in the hybrid vehicle disclosed in Patent Document 1. 5a may be driven. Specifically, this can be realized by transmitting the driving force of the engine 1 from the front differential 3 to the left and right front wheels 5 a via the drive shaft 4 and providing the motor generator 43 in the left and right drive shafts 4.

  In the above embodiment, the motor generator 43 that functions as a motor and a generator is incorporated in the drive shaft 12. However, only the motor is incorporated in the drive shaft 12, and a generator is attached to the engine 1 or the like separately from the motor. Also good. Further, regarding the configuration of the motor generator 43, the outer shaft 24 is connected to the rear differential 11 side and the inner shaft 25 is connected to the rear wheel 5b side in the above embodiment, but the arrangement of both may be reversed.

1 is an overall configuration diagram showing a hybrid vehicle of an embodiment. It is the II-II sectional view taken on the line of FIG. 1 which shows the internal structure of the left drive shaft.

Explanation of symbols

1 Engine 5b Rear wheel (drive wheel)
11 rear differential (differential mechanism)
24 Outer shaft 25 Inner shaft 43 Motor generator (motor mechanism)
47 Slip ring (power supply means)
48 brush (power supply means)
49 Inverter (power supply means, relative rotation restriction means)
54 Locking mechanism (locking means)

Claims (2)

At least one of the front and rear wheels as driving wheels, the hybrid vehicle is driven by arbitrarily transmits the driving force of the engine through a driving force and differential mechanism of the motor mechanism with respect to left and right drive wheels,
An outer shaft disposed between the differential mechanism and the left and right drive wheels, respectively, connected to either the differential mechanism side or the drive wheel side;
The motor mechanism is provided between the outer shaft and disposed on the outer shaft and connected to the other of the differential mechanism side or the drive wheel side, and the motor mechanism provides a relative rotational direction relative to the outer shaft. An inner shaft to which a torque of
Power supply means for supplying power from the vehicle body side to the motor mechanism;
A hybrid vehicle comprising: a relative rotation restricting means for restricting relative rotation between the outer shaft and the inner shaft. 2. The hybrid vehicle according to claim 1, further comprising lock means for fixing the shaft connected to the differential mechanism side.

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