JP5317801B2 - Vehicle drive device - Google Patents

Description

  The present invention relates to a vehicle drive device.

  As a vehicle drive device, the left and right axles of a vehicle are connected to a differential device, and a driving force is transmitted to the differential device via a speed reduction mechanism by an electric motor coaxially arranged on the outer periphery of one axle. Has been devised (see, for example, Patent Document 1).

  As shown in FIG. 13, the driving device 100 includes an axle driving motor 102, a planetary gear type reduction device 112 that decelerates the driving rotation of the electric motor 102, and outputs of the planetary gear type reduction device 112 to the left and right sides of the vehicle. The planetary gear type reduction gear 112 and the electric motor 102 are coaxially arranged on the outer peripheral side of one axle 110B connected to the differential gear 113. The differential gear 113 is distributed to the two axles 110A and 110B. . The sun gear 121 and planetary carrier 123 of the planetary gear reducer 112 are connected to the rotor 115 of the electric motor 102 and the differential case 131 of the differential device 113, respectively, and the ring gear 124 of the planetary gear reducer 112 is fixed to the vehicle body. A hydraulic brake 128 is provided between the ring gear 124 and the speed reducer case 111 so as to engage the ring gear 124 and the speed reducer case 111 and apply a braking force to the ring gear 124. Is described.

  When a braking force is applied to the ring gear 124 by the hydraulic brake 128, the ring gear 124 is fixed to the speed reducer case 111, and the driving force input to the sun gear 121 from the rotor 115 of the electric motor 102 is set by the planetary gear type speed reducer 113. It is decelerated to the ratio and transmitted to the differential case 131 of the differential 113. The driving force transmitted to the differential case 131 is distributed to the left and right axles 110A and 110B by the differential device 112. Further, when the application of the braking force from the hydraulic brake 128 is interrupted, the ring gear 124 rotates freely with respect to the reducer case 111. Therefore, for example, when the braking force applied by the hydraulic brake 128 is interrupted in a situation where the rotational speeds of the axles 110A and 110B are faster than the drive request of the electric motor 102, the ring gear 124 is changed according to the excessive rotation on the axles 110A and 110B side. The engine rotates idly in the speed reducer case 111, and rotation on the axles 110A and 110B side is not input to the motor 102 side. Thereby, when driving or regeneration of the electric motor 102 is unnecessary, the braking force application by the hydraulic brake 128 is cut off to prevent the electric motor 102 from being accompanied and to improve the fuel consumption.

JP 2006-264647 A

However, in the driving device 100 described in Patent Document 1, since the electric motor 102 distributes to the left and right axles 110A and 110B of the vehicle by the differential device 113, the left and right wheels cannot be independently controlled.
In addition, when two electric motors capable of outputting driving force independently are provided on the left and right axles, there is a problem that the driving device becomes larger and the number of parts increases.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a drive device that can independently control both left and right wheels and that can be downsized.

In order to achieve the above object, the invention described in claim 1
A drive device (for example, an electric motor 2A, 2B in an embodiment described later) having two electric motors (for example, electric motors 2A, 2B in an embodiment described later) that can independently output a driving force to left and right drive shafts (for example, axles 10A, 10B in an embodiment described later). In the drive device 1) of the embodiment described later,
Reduction gears (for example, planetary gear type reduction gears 12A and 12B in the embodiments described later) are provided on the power transmission path between the drive shaft and the electric motor,
Each of the reduction gears is composed of three rotation elements (for example, sun gears 21A and 21B, planetary carriers 23A and 23B, and ring gears 24A and 24B in the embodiments described later), and one of the three rotation elements (for example, , Ring gears 24A and 24B) of the embodiments described later are connected to each other,
One- way power transmission means (for example, a one-way clutch 50 according to an embodiment described later) for transmitting one-way rotational power of the motor to the drive shaft to the connected rotating element, and bidirectional of the motor Bi-directional power transmission means (for example, a hydraulic brake 60 according to an embodiment described later) for transmitting the rotational power of the power to the drive shaft ,
The three rotating elements are a sun gear, a carrier, and a ring gear of a planetary gear reducer,
The carrier includes a first pinion (for example, first pinions 26A and 26B in an embodiment described later) that meshes with the sun gear, and a second pinion (for example, described later) that is smaller in diameter than the first pinion and meshes with the ring gear. Supporting the double pinion composed of the second pinion 27A, 27B) of the embodiment,
At least one of the bidirectional power transmission means and the one-way power transmission means wraps in the radial direction with the first pinion of the two-stage pinion of the speed reducer, and wraps in the axial direction with the second pinion. Arranged,
It is characterized by that.
Moreover, in addition to the structure of Claim 1, the invention of Claim 2 is
The bidirectional power transmission means is arranged to wrap in the radial direction with the first pinion of the two-unit pinion of one of the reduction gears, and wrap in the axial direction with the second pinion,
The one-way power transmission means is arranged to wrap in the radial direction with the first pinion out of the two-unit pinions of the other speed reducer, and wrap in the axial direction with the second pinion.
It is characterized by that.

In addition to the configuration described in claim 1 or 2 , the invention described in claim 3
A reduction gear case (for example, a reduction gear case 11 in an embodiment described later) that houses the reduction gear and the electric motor,
The one-way power transmission means is a one-way clutch (for example, a one-way clutch 50 in an embodiment described later),
It said bidirectional power transmission means is a brake (e.g., hydraulic brake 60 in embodiment) for performing connection and disconnection between the reducer case and one rotary element connected to each other,
It is characterized by that.

Moreover, in addition to the structure of Claim 3 , the invention of Claim 4 adds to the structure of Claim 3 ,
The brake is a hydraulic brake that operates hydraulically (for example, a hydraulic brake 60 according to an embodiment described later),
A piston that operates the brake (for example, a piston 37 in an embodiment described later) is disposed between the one-way clutch and the brake.
It is characterized by that.

Moreover, in addition to the structure of Claim 4 , the invention of Claim 5 adds to the structure of Claim 4 ,
Bearings for rotatably supporting one rotary element which are connected to the reducer case (e.g., the bearing 43 of the embodiment) provided with,
The bearing is disposed between the reduction gears facing each other in the axial direction;
It is characterized by that.

Moreover, in addition to the structure of Claim 5 , the invention of Claim 6 is
On the radially outer side of the bearing, the piston of the hydraulic brake is disposed.
It is characterized by that.
Moreover, in addition to the structure in any one of Claims 1-6, the invention of Claim 7 is
Each of the reduction gears is connected to an output shaft of the electric motor (for example, cylindrical shafts 16A and 16B in the embodiments described later) to the sun gear.
It is characterized by that.
Moreover, in addition to the structure in any one of Claims 1-7, the invention of Claim 8 is
The electric motor and the speed reducer are arranged in this order from the outside in the axial direction, and the electric motor and the drive shaft are arranged coaxially,
The motors are also arranged on the same axis,
It is characterized by that.

The invention according to claim 9 is a vehicle (for example, a vehicle 3 according to an embodiment described later) including the drive device according to any one of claims 1 to 8 .

According to the first and ninth aspects of the invention, since the left and right drive shafts are provided with the electric motor and the speed reducer, respectively, the left and right wheels can be controlled independently to improve the steering stability (turning). . Therefore, compared with the case where the turning performance is improved with one motor and two friction materials, the loss due to heat generated by the slip control of the friction material can be suppressed. For example, the optimum specification when mounted on a hybrid vehicle can do.
In addition, by connecting one rotary element among the three rotary elements constituting the left and right speed reducers, a member for controlling the rotary element can be shared, and the drive unit can be downsized and the number of parts can be reduced. Reduction can be achieved.
Furthermore, the one-way power transmission means is arranged so that the power can be transmitted when the electric motor is driven and the vehicle travels forward, so that the one-way transmission means engages without using hydraulic pressure when the vehicle starts. Is transmitted, so that the responsiveness at the start of the vehicle can be improved.
In addition, when the electric motor needs to be driven or regenerated and the one-way power transmission means is opened, the motor can be driven or regenerated by being fixed by the bidirectional power transmission means. When driving and regeneration are unnecessary, it is possible to prevent the motor from being rotated by opening the bidirectional power transmission means. As a result, the electric motor can be operated with the minimum necessary, and fuel consumption can be improved.
Moreover, a large reduction ratio can be obtained with a simple configuration by configuring the reduction gear with a planetary gear type reduction gear.
In addition, by arranging the one-way power transmission means and the two-way power transmission means on the connected rotating elements, both the one-way power transmission means and the two-way power transmission means can be shared by the left and right units, The drive device can be downsized and the number of parts can be reduced.
Further, by using a double pinion as the planetary gear of the planetary gear type speed reducer, a large reduction ratio can be obtained and the electric motor can be miniaturized.
Furthermore, at least one of the bidirectional power transmission means and the one-way power transmission means is disposed so as to wrap in the radial direction with the first pinion of the double pinion of the speed reducer and wrap in the axial direction with the second pinion. Therefore, the length in the radial direction and the axial direction can be reduced, and the drive device can be downsized.
Further, according to the invention described in claim 2, the one-way power transmission means wraps in the radial direction with the large-diameter first pinion out of the double pinions of one of the reduction gears, and the small-diameter second pinion and the axial direction. The two-way power transmission means is arranged to wrap in the radial direction with the large-diameter first pinion out of the two-stage pinion of the other speed reducer and in the axial direction with the small-diameter second pinion. Therefore, the length in the radial direction and the axial direction can be reduced, and the drive device can be downsized.

Furthermore, according to the third aspect of the present invention, the one-way power transmission means is constituted by a one-way clutch, and the bidirectional power transmission means is constituted by a brake. Directional power transmission means can be configured.

Further, according to the invention described in claim 4 , the bidirectional power transmission means is constituted by a hydraulic brake, and the piston for operating the hydraulic brake is disposed between the one-way clutch and the hydraulic brake, whereby the one-way clutch and the hydraulic pressure are set. The space formed between the brakes can be used effectively, and the drive device can be reduced in size.

Furthermore, according to the invention described in claim 5, the bearing rotatably supporting a rotating element coupled to the reducer case, by arranging between the speed reducer facing axially, between the reduction gear Thus, it is possible to effectively use the space formed in the above, and to reduce the size of the driving device.

Furthermore, according to the invention described in claim 6 , by arranging the piston of the hydraulic brake on the outer side in the radial direction of the bearing, the drive device can be downsized by effectively using the space on the outer side in the radial direction of the bearing. Can do.
Furthermore, according to the seventh aspect of the invention, the power of the electric motor can be decelerated and transmitted to the wheels.
Furthermore, according to the invention described in claim 8, the electric motor and the speed reducer are arranged coaxially in this order from the outside in the axial direction, and the electric motors are also arranged coaxially so that the drive device is substantially cylindrical. can do. Thereby, vehicle mounting property can be improved.

1 is a block diagram showing a schematic configuration of a hybrid vehicle that is an embodiment of a vehicle to which a drive device according to the present invention can be applied. It is a longitudinal cross-sectional view of the drive device which concerns on this invention. FIG. 3 is a partially enlarged view of the drive device shown in FIG. 2. It is a perspective view which shows the state with which the drive device based on this invention was mounted in the flame | frame. It is an alignment chart of the drive device when the vehicle is stopped. It is a collinear diagram of the drive device when the drive device is on the drive side and travels forward. FIG. 6 is a collinear diagram of the drive device when the drive device travels forward on the coast side and the motor stops. FIG. 5 is a collinear diagram of the drive device when the drive device travels forward on the coast side and the motor is regenerated. It is an alignment chart of the drive device when the drive device is on the drive side and travels backward. It is a collinear diagram of the drive device when the drive device is traveling on the coast side and traveling backward. It is the figure which showed the state of the electric motor in the driving | running | working state of a vehicle, and the state of the separation mechanism. It is a driving force characteristic figure of the electric motor of a drive device. 2 is a longitudinal sectional view of a drive device described in Patent Document 1. FIG.

An embodiment of the present invention will be described below with reference to FIGS.
A drive device 1 according to the present invention uses electric motors 2A and 2B as drive sources for driving an axle, and is used for a vehicle 3 having a drive system as shown in FIG. 1, for example.
A vehicle 3 shown in FIG. 1 is a hybrid vehicle having a drive unit 6 in which an internal combustion engine 4 and an electric motor 5 are connected in series at the front part of the vehicle, and the power of the drive unit 6 is transmitted to a front wheel Wf via a transmission 7. On the other hand, the power of the drive device 1 according to the present invention provided at the rear of the vehicle separately from the drive unit 6 is transmitted to the rear wheels Wr (RWr, LWr). The electric motor 5 of the driving unit 6 and the electric motors 2A and 2B of the driving device 1 on the rear wheel Wr side are connected to the battery 9 via a PDU 8 (power drive unit), and supply of power from the battery 9 and energy regeneration to the battery 9 are performed. Is performed via the PDU 8.

  FIG. 2 is a longitudinal sectional view of the entire drive device 1. In FIG. 2, 10A and 10B are left and right axles on the rear wheel Wr side of the vehicle, and are arranged coaxially in the vehicle width direction. ing. The reduction gear case 11 of the drive device 1 is formed in a substantially cylindrical shape as a whole, and includes an axle driving motor 2A, 2B, and a planetary gear type reduction gear 12A for reducing the drive rotation of the motor 2A, 2B. , 12B are arranged coaxially with the axles 10A, 10B. The electric motor 2A and the planetary gear type reduction gear 12A control the left rear wheel LWr, and the electric motor 2B and the planetary gear type reduction gear 12B control the right rear wheel RWr, and the electric motor 2A, the planetary gear type reduction gear 12A, the electric motor 2B, The planetary gear type speed reducer 12B is disposed symmetrically in the vehicle width direction within the speed reducer case 11. As shown in FIG. 4, the speed reducer case 11 is supported by the support portions 13 a and 13 b of the frame member 13 that is a part of the frame that is the skeleton of the vehicle 3 and the frame of the drive device 1 (not shown). Yes. The support portions 13a and 13b are provided on the left and right with respect to the center of the frame member 13 in the vehicle width direction. In addition, the arrow in FIG. 4 has shown the positional relationship in the state in which the drive device 1 was mounted in the vehicle.

  The stators 14A and 14B of the electric motors 2A and 2B are respectively fixed inside the left and right ends of the speed reducer case 11, and annular rotors 15A and 15B are rotatably arranged on the inner peripheral sides of the stators 14A and 14B. . Cylindrical shafts 16A and 16B surrounding the outer periphery of the axles 10A and 10B are coupled to the inner peripheral portions of the rotors 15A and 15B, and the cylindrical shafts 16A and 16B are decelerated so as to be coaxially rotatable with the axles 10A and 10B. The machine case 11 is supported by end walls 17A and 17B and intermediate walls 18A and 18B via bearings 19A and 19B. In addition, the rotational position information of the rotors 15A and 15B is transmitted to the end walls 17A and 17B of the reduction gear case 11 on the outer periphery on one end side of the cylindrical shafts 16A and 16B, and the control controllers (not shown) of the motors 2A and 2B. Resolvers 20A and 20B are provided for feedback.

  The planetary gear speed reducers 12A and 12B include sun gears 21A and 21B, a plurality of planetary gears 22A and 22B meshed with the sun gear 21, planetary carriers 23A and 23B that support the planetary gears 22A and 22B, and planetary gears. Ring gears 24A and 24B meshed with the outer peripheral sides of 22A and 22B, and the driving forces of the electric motors 2A and 2B are input from the sun gears 21A and 21B, and the reduced driving force is output through the planetary carriers 23A and 23B. It is like that.

  The sun gears 21A and 21B are formed integrally with the cylindrical shafts 16A and 16B. The planetary gears 22A and 22B are double pinions having first pinions 26A and 26B having large diameters directly meshed with the sun gears 21A and 21B, and second pinions 27A and 27B having smaller diameters than the first pinions 26A and 26B. The first pinions 26A and 26B and the second pinions 27A and 27B are integrally formed in a state of being coaxial and offset in the axial direction. The planetary gears 22A and 22B are supported by the planetary carriers 23A and 23B, and the planetary carriers 23A and 23B are supported so as to be integrally rotatable with the axially inner ends extending inward in the radial direction and being spline-fitted to the axles 10A and 10B. Along with the bearings 33A and 33B, the intermediate walls 18A and 18B are supported.

  The intermediate walls 18A and 18B separate the motor housing space for housing the motors 2A and 2B and the speed reducer space for housing the planetary gear type speed reducers 12A and 12B, and the axial distance from the outer diameter side to the inner diameter side. It is configured to bend so as to spread. Bearings 33A and 33B that support the planetary gears 22A and 22B are arranged on the inner diameter side of the intermediate walls 18A and 18B and on the planetary gear type speed reducers 12A and 12B, and the outer diameter side of the intermediate walls 18A and 18B. In addition, bus rings 41A and 41B for the stators 14A and 14B are arranged on the motors 2A and 2B side.

  The ring gears 24A and 24B are disposed opposite to each other at gears 28A and 28B whose inner peripheral surfaces are meshed with the second pinions 27A and 27B having a small diameter, and smaller in diameter than the gear parts 28A and 28B, at an intermediate position of the speed reducer case 11. Small-diameter portions 29A and 29B, and connecting portions 30A and 30B that connect the axially inner ends of the gear portions 28A and 28B and the axially outer ends of the small-diameter portions 29A and 29B in the radial direction. . In the case of this embodiment, the maximum radii of the ring gears 24A and 24B are set to be smaller than the maximum distance from the center of the axles 10A and 10B of the first pinions 26A and 26B. The small diameter portions 29 </ b> A and 29 </ b> B are rotatably supported via a bearing 43 on a cylindrical support portion 42 of the speed reducer case 11 facing radially outside and are connected by a retaining ring 44. The cylindrical support portion 42 extends from the radially inner end portion of the support wall 39 extending radially inward from the position deviated toward the planetary gear type speed reducer 12B to the planetary gear type speed reducer 12A side. It is extended.

  By the way, a cylindrical space is secured between the reduction gear case 11 and the ring gear 24A, and a hydraulic brake 60 constituting a braking means for the ring gears 24A and 24B is wrapped in the radial direction with the first pinion 26A in the space. The second pinion 27A is disposed so as to wrap in the axial direction. In the hydraulic brake 60, a plurality of fixed plates 35 that are spline-fitted to the inner peripheral surface of the speed reducer case 11 and a plurality of rotary plates 36 that are spline-fitted to the outer peripheral surface of the ring gear 24A are alternately arranged in the axial direction. These plates 35 and 36 are engaged and released by an annular piston 37. The piston 37 is accommodated in an annular cylinder chamber 38 formed between the speed reducer case 11, the support wall 39, and the cylindrical support portion 42, and the piston 37 is inserted into the cylinder chamber 38 by introduction of high-pressure oil. The piston 37 is moved backward by discharging the oil from the cylinder chamber 38. As shown in FIG. 4, the hydraulic brake 60 is connected to the oil pump 70 disposed between the support portions 13a and 13b of the frame member 13 described above.

In more detail, the piston 37 has a first piston wall 63 and a second piston wall 64 in the axial direction, and these piston walls 63, 64 are connected by a cylindrical inner peripheral wall 65. Therefore, an annular space that opens radially outward is formed between the first piston wall 63 and the second piston wall 64, and this annular space is a partition fixed to the inner peripheral surface of the outer wall of the cylinder chamber 38. The member 66 is partitioned forward and backward in the axial direction. A space between the support wall 39 of the reduction gear case 11 and the second piston wall 64 is a first working chamber into which high-pressure oil is directly introduced, and a space between the partition member 66 and the first piston wall 63 is formed on the inner peripheral wall 65. The second working chamber is connected to the first working chamber through the through hole. The second piston wall 64 and the partition member 66 are electrically connected to the atmospheric pressure.
In the hydraulic brake 60, high pressure oil is introduced into the first working chamber and the second working chamber, and the fixed plate 35 and the rotating plate 36 are mutually connected by the pressure of the oil acting on the first piston wall 63 and the second piston wall 64. It can be pressed. Therefore, since the large pressure receiving area can be gained by the first and second piston walls 63 and 64 in the front and rear in the axial direction, a large pressing force against the fixed plate 35 and the rotating plate 36 can be obtained while the radial area of the piston 37 is suppressed. Can be obtained.

  In the case of this hydraulic brake 60, since the fixed plate 35 is supported by the speed reducer case 11 and the rotating plate 36 is supported by the ring gear 24A, when both plates 35, 36 are pressed by the piston 37, both plates When the braking force is applied to the ring gears 24A and 24B connected to each other by frictional engagement between the pistons 37 and the piston 37 is released from this state, the ring gears 24A and 24B connected to each other are free. Rotation is allowed.

  A cylindrical space is also secured between the reduction gear case 11 and the ring gear 24B, and only one direction of power is transmitted to the ring gears 24A and 24B and the power in the other direction is cut off in the space. A clutch 50 is arranged. The one-way clutch 50 has a large number of sprags 53 interposed between an inner race 51 and an outer race 52, and the inner race 51 is configured integrally with the gear portion 28B of the ring gear 24B. The outer race 52 is positioned by the inner peripheral surface of the speed reducer case 11 and is prevented from rotating. The one-way clutch 50 is configured to engage and lock the rotation of the ring gears 24A and 24B when the vehicle moves forward. More specifically, the one-way clutch 50 is configured to lock or disconnect the ring gears 24A and 24B depending on the direction of the torque acting on the ring gears 24A and 24B, and the rotation of the sun gears 21A and 21B when the vehicle moves forward. When the direction is the forward rotation direction, the rotation of the ring gears 24A and 24B is locked when the torque in the reverse rotation direction acts on the ring gears 24A and 24B.

  In the drive device 1 configured as described above, the planetary gear speed reducers 12A and 12B face each other in the axial direction at the center, and the ring gear 24A of the planetary gear speed reducer 12A and the ring gear 24B of the planetary gear speed reducer 12B are connected. The ring gears 24 </ b> A and 24 </ b> B are rotatably supported by a cylindrical support portion 42 of the reduction gear case 11 via a bearing 43. Further, a hydraulic brake 60 is provided in a space between the outer diameter side of the planetary gear speed reducer 12A and the speed reducer case 11, and a space between the outer diameter side of the planetary gear speed reducer 12B and the speed reducer case 11 is provided. A one-way clutch 50 is provided, and a piston 37 that operates the hydraulic brake 60 is disposed between the hydraulic brake 60 and the one-way clutch 50 and on the outer diameter side of the bearing 34.

  Next, control of the drive device 1 configured as described above will be described. 5 to 10 show collinear diagrams in each state, and S and C on the left side are a sun gear 21A of a planetary gear type reduction gear 12A connected to the electric motor 2A and a planetary carrier 23A connected to the axle 10A, respectively. S and C on the right side are the sun gear 21B of the planetary gear type speed reducer 12B connected to the electric motor 2B, the planetary carrier 23B connected to the axle 10B, R is the ring gears 24A and 24B, BRK is the hydraulic brake 60, and OWC is one-way. The clutch 50 is represented. In the following description, the rotation direction of the sun gears 21A and 21B during forward movement is defined as the forward rotation direction. Further, in the figure, from the stationary state, the upper direction is the rotation in the forward direction, the lower direction is the rotation in the reverse direction, and the arrow indicates the torque in the normal direction, and the lower side indicates the torque in the reverse direction.

  FIG. 5 is an alignment chart when the vehicle is stopped. At this time, since the electric motors 2A and 2B are stopped and the axles 10A and 10B are stopped, no torque acts on any of the elements.

  FIG. 6 is a collinear diagram when the vehicle travels forward by the motor torque of the electric motors 2A and 2B of the drive device 1, that is, when the vehicle moves forward with the drive device 1 on the drive side. When the electric motors 2A and 2B are driven, torque in the forward rotation direction is applied to the sun gears 21A and 21B. At this time, as described above, the ring gears 24A and 24B are locked by the one-way clutch 50, and a lock torque in the forward direction is applied to the ring gears 24A and 24B that are about to rotate in the reverse direction. As a result, the planetary carriers 23A, 23B rotate in the forward rotation direction and travel forward. Note that the running resistance from the axles 10A and 10B acts in the reverse direction on the planetary carriers 23A and 23B. Thus, when the vehicle is traveling, the ignition is turned on and the torque of the electric motors 2A and 2B is increased, whereby the one-way clutch 50 is mechanically engaged and the ring gears 24A and 24B are locked. The vehicle can be started without operating the oil pump 70 that operates the. Thereby, the responsiveness at the time of vehicle start can be improved.

  FIG. 7 shows a case where the electric motors 2A and 2B are stopped in a state where the vehicle is traveling forward by the drive unit 6 or pulled forward by another vehicle or the like, that is, the driving device 1 is on the coast side and the electric motor It is an alignment chart in case 2A and 2B stop. When the motors 2A and 2B are stopped from the state shown in FIG. 6, the forward rotation torque is applied to the planetary carriers 23A and 23B from the axles 10A and 10B, so that the forward rotation is applied to the ring gears 24A and 24B. The one-way clutch 50 is released by the action of the torque. Accordingly, the ring gears 24A and 24B idle at a higher speed than the planetary carriers 23A and 23B. As a result, when it is not necessary to regenerate with the electric motors 2A and 2B, if the ring gears 24A and 24B are not fixed by the hydraulic brake 60, the electric motors 2A and 2B are stopped, and the accompanying rotation of the electric motors 2A and 2B can be prevented. it can. At this time, the cogging torque in the forward direction acts on the electric motors 2A and 2B, and the total torque that balances the cogging torque and the friction of the ring gears 24A and 24B becomes the axle loss of the axles 10A and 10B.

  FIG. 8 shows a case where the vehicle is driven forward by the drive unit 6 and is regenerated by the electric motors 2A and 2B in a natural deceleration state with the accelerator off and a braking deceleration by the brake. It is a collinear diagram in case the motors 2A and 2B are regenerated on the side. When the motors 2A and 2B are regenerated from the state shown in FIG. 6, the forward rotation torque is applied to the planetary carriers 23A and 23B from the axles 10A and 10B, so that the forward rotation is applied to the ring gears 24A and 24B. The one-way clutch 50 is released by the action of the torque. At this time, by engaging the hydraulic brake 60 and applying a lock torque in the reverse direction to the ring gears 24A and 24B, the ring gears 24A and 24B are fixed and a regenerative torque in the reverse direction acts on the motors 2A and 2B. . Thereby, regenerative charging can be performed by the electric motors 2A and 2B.

  FIG. 9 is a collinear diagram when the vehicle travels backward by the motor torque of the electric motors 2A and 2B of the drive device 1, that is, when the drive device 1 moves backward on the drive side. When the motors 2A, 2B are driven in the reverse direction, torque in the reverse direction is applied to the sun gears 21A, 21B. At this time, forward torque acts on the ring gears 24A and 24B, and the one-way clutch 50 is released. At this time, by engaging the hydraulic brake 60 and applying a locking torque in the reverse direction to the ring gears 24A and 24B, the ring gears 24A and 24B are fixed and the planetary carriers 23A and 23B rotate in the reverse direction and travel backward. Made. Note that running resistance from the axles 10A and 10B acts in the forward direction on the planetary carriers 23A and 23B.

  FIG. 10 is a collinear diagram of the drive device 1 on the coast side when the vehicle is traveling backward by the drive unit 6 or when the vehicle is being pulled in the backward direction by another vehicle or the like, that is, when traveling backward. At this time, torque in the reverse direction to continue the reverse travel from the axles 10A and 10B acts on the planetary carriers 23A and 23B. Therefore, the ring gears 24A and 24B are locked by the one-way clutch 50 to rotate in the reverse direction. The forward rotation direction lock torque is applied to the ring gears 24A and 24B, and the motors 2A and 2B generate back electromotive force in the forward rotation direction.

  FIG. 11 is a diagram showing the states of the electric motors 2A and 2B and the state of the separation mechanism (one-way clutch 50 and hydraulic brake 60) in the traveling state of the vehicle. Note that the front means the drive unit 6 that drives the front wheel Wf, the rear means the drive device 1 that drives the rear wheel Wr, ○ means activation (including drive and regeneration), and x means non-operation (stop). Further, the MOT state means the state of the electric motors 2A and 2B of the driving device 1. Furthermore, OWC means the one-way clutch 50, and the brake means the hydraulic brake 60.

  While the vehicle is stopped, the electric motors 2A and 2B of the driving device 1 are stopped, the driving unit 6 on the front wheel Wf side and the driving device 1 on the rear wheel Wr side are both stopped, and the separation mechanism is also inoperative. ing.

  Then, after the ignition is turned on, the electric motors 2A and 2B of the driving device 1 for the rear wheel Wr are driven when the EV starts. At this time, as described with reference to FIG. 6, the separation mechanism is locked by the one-way clutch 50, and the power of the electric motors 2A and 2B is transmitted to the axles 10A and 10B.

  Subsequently, during acceleration, the four-wheel drive of the drive unit 6 on the front wheel Wf side and the drive device 1 on the rear wheel Wr side is performed, and also at this time, the separation mechanism is locked by the one-way clutch 50, as described in FIG. The power of the electric motors 2A and 2B is transmitted to the axles 10A and 10B.

  In the EV cruise in the low / medium speed range, since the motor efficiency is good, the driving unit 6 on the front wheel Wf side is inactive and the driving device 1 on the rear wheel Wr side performs rear wheel driving. Also at this time, as described with reference to FIG. 6, the separation mechanism is locked by the one-way clutch 50, and the power of the electric motors 2A, 2B is transmitted to the axles 10A, 10B.

  On the other hand, in high-speed cruise in the high speed region, the engine efficiency is good, so that the front wheel drive is performed by the drive unit 6 on the front wheel Wf side. At this time, as described with reference to FIG. 7, the one-way clutch 50 of the separation mechanism is disengaged (OWC free) and the hydraulic brake 60 is not operated, so the electric motors 2A and 2B are stopped.

  In the case of natural deceleration, as described with reference to FIG. 7, the one-way clutch 50 of the disengaging mechanism is disengaged (OWC free) and the hydraulic brake 60 is not operated, so that the electric motors 2A and 2B are stopped.

  On the other hand, when decelerating and regenerating, for example, when driving by the driving force of the driving unit 6 on the front wheel Wf side, the one-way clutch 50 of the disengaging mechanism is disconnected (OWC free) as described with reference to FIG. By engaging the brake 60, regenerative charging is performed by the electric motors 2A and 2B.

  In normal driving, the motor 2A, 2B regenerates and recovers the traveling energy in cooperation with the vehicle brake braking control. However, when emergency braking is required (ABS operation), the regeneration of the motors 2A, 2B is prohibited and the vehicle brake is disabled. Prioritize. In this case, the one-way clutch 50 is disconnected (OWC free), and the electric motors 2A and 2B are stopped by not operating the hydraulic brake 60.

  In the case of reverse travel, the driving unit 6 on the front wheel Wf side stops and the driving device 1 on the rear wheel Wr side is driven to perform rear wheel driving, or the driving unit 6 on the front wheel Wf side and driving on the rear wheel Wr side are driven. The four-wheel drive of the device 1 is performed. At this time, as described with reference to FIG. 9, the motors 2A and 2B rotate in the reverse direction, and the one-way clutch 50 of the disengagement mechanism is disconnected (OWC free), but by connecting the hydraulic brake 60, the motor 2A 2B power is transmitted to the axles 10A and 10B.

  In the case of being pulled in the forward direction (FWD towed), as described with reference to FIG. 7, the one-way clutch 50 of the separation mechanism is disconnected (OWC free) and the hydraulic brake 60 is not operated. 2B stops. In the case of regenerating the motors 2A, 2B in the case of FWD towing, the hydraulic brake 60 is connected in the same manner as during deceleration regeneration.

  Further, when the motors 2A and 2B cannot be driven due to a high voltage system failure such as a failure of a PDU or the like, the front wheel drive is performed by the drive unit 6 on the front wheel Wf side. At this time, as described with reference to FIG. 7, the one-way clutch 50 of the separation mechanism is disengaged (OWC free) and the hydraulic brake 60 is not operated, so the electric motors 2A and 2B are stopped.

FIG. 12 is a driving force characteristic diagram during forward travel (FWD drive), forward travel regeneration (FWD regeneration), and reverse travel (RVS drive) by the electric motors 2A and 2B of the drive device 1. In the figure, the upper right represents the axle torque during forward travel (FWD drive), the lower right represents the axle torque during forward travel regeneration (FRD regeneration), and the upper left represents the axle torque during reverse travel (RVS drive).
As shown in FIG. 12, the axle torque during FWD regeneration and RVS drive in the drive device 1 of the present invention is set lower than the axle torque during FWD drive. As a result, during FWD regeneration and RVS driving, braking is performed by the hydraulic brake 60 as described with reference to FIGS. 8 and 9. However, since the regenerative torque and reverse torque are set low, the brake capacity can be reduced. Therefore, the fixed plates 35A and 35B and the rotating plates 36A and 36B can be reduced, and the pump loss can be reduced by setting a low hydraulic pressure.

As described above, according to the driving apparatus 1 according to the present embodiment described above, the left and right wheels LWr and RWr are independent from each other because the motors 2A and 2B and the planetary gear type speed reducers 12A and 12B are provided on the left and right drive shafts 10A and 10B, respectively. It is possible to improve the steering stability (turning) by controlling. Therefore, compared with the case where the turning performance is improved with one motor and two friction materials, the loss due to heat generated by the slip control of the friction material can be suppressed. For example, the optimum specification when mounted on a hybrid vehicle can do.
Further, by connecting the ring gears 24A and 24B, which are one of the three rotating elements constituting the left and right planetary gear speed reducers 12A and 12B, to control the rotation of the ring gears 24A and 24B, For example, the one-way clutch 50 and the hydraulic brake 60 can be shared, and the drive unit 1 can be reduced in size and the number of parts can be reduced.

Furthermore, according to the drive device 1 according to the present embodiment, the hydraulic pressure is increased when the vehicle starts by disposing the one-way clutch 50 so that power can be transmitted when the motors 2A and 2B are driven to travel forward. Since power is transmitted by engaging the one-way clutch 50 without using it, the responsiveness at the time of vehicle start can be improved.
In addition, when the electric motors 2A and 2B need to be driven and regenerated, and the one-way clutch 50 is released, the electric motors 2A and 2B can be driven and regenerated by engaging the hydraulic brake 60. In addition, when it is not necessary to drive or regenerate the electric motors 2A and 2B, it is possible to prevent the electric motors 2A and 2B from being rotated by opening the hydraulic brake 60. As a result, the electric motors 2A and 2B can be operated with the minimum necessary, and fuel consumption can be improved.

  Furthermore, according to the drive device 1 according to the present embodiment, the one-way clutch 50 and the hydraulic brake 60 are both arranged on the left and right units by arranging the one-way clutch 50 and the hydraulic brake 60 on the ring gears 24A and 24B connected to each other. Can be shared.

  Furthermore, according to the drive device 1 according to the present embodiment, the common one-way clutch 50 and the hydraulic brake 60 are respectively connected to one side and the other in the axial direction, that is, the planetary gear type speed reducer 12B side and the planetary gear type speed reducer. By disposing on the 12A side, the length in the radial direction can be reduced and the drive device 1 can be downsized.

  Furthermore, according to the drive device 1 according to the present embodiment, the one-way power transmission means is constituted by the one-way clutch 50, and the bidirectional power transmission means is constituted by a brake. And a bi-directional power transmission means.

  Furthermore, according to the drive device 1 according to the present embodiment, the bidirectional power transmission means is configured by the hydraulic brake 60, and the piston 37 that operates the hydraulic brake 60 is disposed between the one-way clutch 50 and the hydraulic brake 60. The space formed between the one-way clutch 50 and the hydraulic brake 60 can be used effectively, and the drive device 1 can be reduced in size.

  Furthermore, according to the drive device 1 which concerns on this embodiment, a big reduction ratio can be obtained with a simple structure by comprising a reduction gear by planetary gear type reduction gears 12A and 12B.

  Furthermore, according to the drive device 1 according to the present embodiment, by using the double pinion as the planetary gears 22A and 22B of the planetary gear speed reducers 12A and 12B, the reduction ratio can be increased, and the electric motors 2A and 2B can be It can be downsized. The one-way clutch 50 is arranged to wrap in a radial direction with a large-diameter first pinion 26B of two planetary pinions of the planetary gear type speed reducer 12B, and wrap in an axial direction with a small-diameter second pinion 27B. Since the brake 60 is arranged to wrap in the radial direction with the large-diameter first pinion 26A of the two-stage pinion of the planetary gear type speed reducer 12A and axially wrap with the small-diameter second pinion 27A, The length in the axial direction can be reduced, and the drive device 1 can be downsized.

  Furthermore, according to the drive device 1 according to the present embodiment, the electric motors 2A and 2B and the planetary gear type speed reducers 12A and 12B are arranged coaxially in this order from the outside in the axial direction, and the electric motors 2A and 2B are coaxial. The drive device 1 can be formed in a substantially cylindrical shape. Thereby, vehicle mounting property can be improved.

  Furthermore, according to the drive device 1 according to the present embodiment, the planetary gear type speed reducers 12A and 12B that are axially opposed to the bearings 43 that rotatably support the ring gears 24A and 24B connected to the speed reducer case 11 are provided. By disposing them in between, the space formed between the planetary gear speed reducers 12A and 12B can be used effectively, and the drive device 1 can be miniaturized.

  Furthermore, according to the drive device 1 according to the present embodiment, the piston 37 of the hydraulic brake 60 is disposed on the radially outer side of the bearing 43, thereby effectively using the space on the radially outer side of the bearing 43. 1 can be reduced in size.

  In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.

1 Drive device (drive device)
2A Electric motor 2B Electric motor 10A Axle (drive shaft)
10B Axle (drive shaft)
11 Reduction gear case 12A Planetary gear type reduction gear (reduction gear)
12B Planetary gear reducer (reduction gear)
16A, 16B Cylindrical shaft (output shaft)
21A, 21B Sun gear (first rotating element)
23A, 23B Planetary carrier (carrier, second rotating element)
24A, 24B Ring gear (third rotating element)
26A, 26B First pinion 27A, 27B Second pinion 37 Piston 43 Bearing 50 One-way clutch (one-way power transmission means)
60 Hydraulic brake (brake, bidirectional power transmission means)
Wf Front wheel LWr Left rear wheel RWr Right rear wheel

Claims (9)

In a drive device comprising two electric motors capable of outputting drive force independently to the left and right drive shafts,
Reducers are respectively provided on the power transmission paths between the drive shaft and the electric motor,
Each of the reduction gears is composed of three rotating elements, and one rotating element among the three rotating elements is connected to each other,
One- way power transmission means for transmitting the one-way rotational power of the electric motor to the drive shaft to the connected one rotary element, and two- way power for transmitting the two-way rotational power of the motor to the drive shaft and transmission means, been arranged,
The three rotating elements are a sun gear, a carrier, and a ring gear of a planetary gear reducer,
The carrier supports a double pinion composed of a first pinion that meshes with the sun gear and a second pinion that is smaller in diameter than the first pinion and meshes with the ring gear;
At least one of the bidirectional power transmission means and the one-way power transmission means wraps in the radial direction with the first pinion of the two-stage pinion of the speed reducer, and wraps in the axial direction with the second pinion. Arranged,
A drive device characterized by that.   The bidirectional power transmission means is arranged to wrap in the radial direction with the first pinion of the two-unit pinion of one of the reduction gears, and wrap in the axial direction with the second pinion,
  The one-way power transmission means is arranged to wrap in the radial direction with the first pinion out of the two-unit pinions of the other speed reducer, and wrap in the axial direction with the second pinion.
  The drive device according to claim 1. A speed reducer case that houses the speed reducer and the electric motor;
The one-way power transmission means is a one-way clutch;
It said bidirectional power transmission means is a brake to perform disengagement between the reducer case and one rotary element that is the connecting,
The drive device according to claim 1 , wherein the drive device is provided. The brake is a hydraulic brake that operates hydraulically,
A piston for operating the brake is disposed between the one-way clutch and the brake;
The drive device according to claim 3 . Comprising a bearing for rotatably supporting one rotary element which are connected to the reducer case,
The bearing is disposed between the reduction gears facing each other in the axial direction;
The drive device according to claim 4 . On the radially outer side of the bearing, the piston of the hydraulic brake is disposed.
The drive device according to claim 5 . The speed reducer, the output shaft of each of the electric motor to the sun gear is connected, the drive shaft is coupled to the carrier,
The drive device according to any one of claims 1 to 6 , wherein The electric motor and the speed reducer are arranged in this order from the outside in the axial direction, and the electric motor and the drive shaft are arranged coaxially,
The motors are also arranged on the same axis,
The drive device according to any one of claims 1 to 7 , wherein A vehicle provided with the drive device of any one of Claims 1-8 .

Images