JP2011031746A - Drive control device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drive control device for a vehicle capable of reducing any impact due to backlash even when the rotational direction of the gear of a reduction gear on a power transmission path is changed. <P>SOLUTION: The drive control device for a vehicle is provided with: a drive source capable of outputting drive power to a first axle which is one of the front and rear wheel axles; an electric motor capable of outputting a drive power to a second axle which is the other axle; a reduction gear installed on a power transmission path between a second axle and the electric motor; a unidirectional power transmitting unit for transmitting the vehicle drive power from the electric motor to the second axle; and a brake for transmitting a rotational power from the second axle to the electric motor when the regenerative drive of the electric motor is performed. The drive control device for a vehicle is also provided with: a vehicle speed detection means; a means for determining the target rotational speed of the electric motor on the basis of the speed of the vehicle; a means for detecting the rotational speed of the electric motor; and a control unit which, when starting the drive of the electric motor in the traveling state of the vehicle from the drive source, controls the electric motor so that the rotational speed of the electric motor is synchronized with the target rotational speed, and controls the output torque of the electric motor or the drive of the brake. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a drive control device for a vehicle using a plurality of drive sources in combination.

  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. 22, the driving device 100 includes an axle driving electric motor 102, a planetary gear type reduction gear 112 that decelerates the driving rotation of the electric motor 102, and outputs of the planetary gear type reduction gear 112 from 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 from the rotor 115 of the electric motor 102 to the sun gear 121 is set by the planetary gear type speed reducer 112. It is decelerated to the ratio and transmitted to the differential case 131 of the differential device 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 113. 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 application of the braking force by the hydraulic brake 128 is interrupted in a situation where the rotational speed of the axles 110A and 110B is faster than the drive request of the electric motor 102, the ring gear 124 is responded to the excess rotation on the axles 110A and 110B side. Runs idle in the reducer case 111, and the rotation on the axles 110A, 110B side is not input to the motor 102 side. Thereby, when driving or regeneration of the electric motor 102 is unnecessary, the application of the braking force by the hydraulic brake 128 is cut off to prevent the electric motor 102 from being accompanied and to improve fuel efficiency.

JP 2006-264647 A

  The driving device 100 described above applies a braking force by the hydraulic brake 128 to the ring gear 124 when the electric motor 102 needs to be driven or regenerated. In this state, since the ring gear 124 is fixed to the reduction gear case 111, the driving force is transmitted between the sun gear 121 and the planetary carrier 123 of the planetary gear type reduction gear 112. As a result, torque is transmitted between the axles 110A and 110B and the electric motor 102.

  On the other hand, the driving device 100 does not apply the braking force by the hydraulic brake 128 to the ring gear 124 when the driving and regeneration of the electric motor 102 are unnecessary. In this state, the ring gear 124 idles in the speed reducer case 111, so that no driving force is transmitted between the sun gear 121 and the planetary carrier 123. Accordingly, torque is not transmitted between the axles 110A and 110B and the electric motor 102.

  In the case of a vehicle in which the electric motor 102 is used as an auxiliary drive source of the vehicle and an internal combustion engine or the like is used as the main drive source, the drive device 100 switches to one of these two states according to the traveling state of the vehicle. . For example, when the vehicle is traveling at high speed, the vehicle travels only by the driving force from the internal combustion engine. At this time, if a torque transmission path is fastened between the axles 110A and 110B and the electric motor 102, the rotor of the electric motor 102 is forcibly rotated by the rotational force on the axles 110A and 110B. Therefore, the driving device 100 releases the application of the braking force to the ring gear 124 by the hydraulic brake 128. On the other hand, when the vehicle starts or decelerates, the driving force from the electric motor 102 is used. At this time, the driving device 100 applies a braking force by the hydraulic brake 128 to the ring gear 124.

  Thus, depending on the running state of the vehicle, the braking force by the hydraulic brake 128 is applied to or released from the ring gear 124, and the state between the sun gear 121 and the planetary carrier 123 changes each time. Torque transmitted between the sun gear 121 and the planetary carrier 123 is transmitted through at least two gears facing each other. As shown in FIG. 23, a gap called “backlash” is provided between the teeth of the two gears that are engaged with each other. This backlash allows the gears to move freely. However, when a gear that has been rotating in one direction is rotated in the opposite direction, or when the gear is rotated in a direction in which backlash exists from a non-rotating state, an impact occurs. This impact causes vibration and noise and also reduces the life of the machine.

  Therefore, even if the rotation direction of the gear existing between the sun gear 121 and the planetary carrier 123 is changed by applying or releasing the braking force to the ring gear 124, the control that can reduce the impact caused by the backlash is possible. It is desirable to be done.

  An object of the present invention is to provide a vehicle drive control device that can reduce the impact caused by backlash even if the rotation direction of the gear of the reduction gear on the power transmission path changes.

  In order to solve the above problems and achieve the object, a drive control device according to a first aspect of the present invention is a first axle that is one of the front and rear wheel shafts (for example, the main drive shaft in the embodiment). 8) a driving source capable of outputting driving force (for example, the internal combustion engine 4 and the electric motor 5 in the embodiment) and a second axle (for example, an axle in the embodiment) which is the other of the front and rear wheel shafts. 10A and 10B) (for example, motors 2A and 2B in the embodiment) and a reduction gear (for example, provided on a power transmission path between the second axle and the motor) The planetary gear type speed reducers 12A and 12B) in the embodiment are provided in series with the speed reducer on the power transmission path, and the power driving force from the electric motor is supplied to the second through the speed reducer. One-way power transmission part that transmits to the axle (for example, in the embodiment Directional clutch 50) is provided in parallel with the one-way power transmission unit on the power transmission path, and when the electric motor is regeneratively driven, the rotational power from the second axle is transmitted through the speed reducer through the speed reducer. A drive control device for a vehicle (for example, the vehicle 3 in the embodiment) including a brake (for example, the hydraulic brakes 60A and 60B in the embodiment) that transmits to the electric motor, A first detector that detects the rotational speed of the second axle (for example, the vehicle speed sensor 117 or the rotational speed sensors 117a and 117b in the embodiment), the speed of the vehicle detected by the detector, or the second speed Based on the rotational speed of the axle, a target rotational speed determination unit (for example, management ECU 9 in the embodiment) that determines the target rotational speed of the electric motor, and a second detection unit that detects the rotational speed of the electric motor (for example, When the driving of the electric motor is started in a state where the vehicle is running by the driving force from the resolver 20A, 20B and the management ECU 9) and the driving source in the embodiment, the rotational speed of the electric motor is set to the target And a control unit (for example, the management ECU 9 in the embodiment) that controls the electric motor so as to synchronize with the rotational speed and controls the output torque of the electric motor or the driving of the brake. .

  Furthermore, in the drive control device according to the second aspect of the present invention, when the motor is regeneratively driven, the control unit, when the rotational speed of the motor reaches a threshold rotational speed lower than the target rotational speed, The bidirectional power transmission unit is actuated.

  Furthermore, in the drive control device of the invention according to claim 3, the control unit, when the electric motor is driven by power running, when the rotational speed of the motor reaches a threshold rotational speed lower than the target rotational speed, The electric motor is controlled so as to output a predetermined torque.

  Furthermore, in the drive control apparatus according to the invention described in claim 4, the predetermined torque is a constant torque necessary for the rotational speed of the electric motor to synchronize with the target rotational speed.

  Furthermore, in the drive control device according to the fifth aspect of the present invention, the vehicle includes left and right wheels (for example, the left rear wheel LWr and the right rear wheel RWr in the embodiment) provided on the second axle side. Are provided with the electric motor, the speed reducer, the brake, and the second axle, and the control unit is in a state in which the vehicle is running while turning by the driving force from the driving source. When driving of the electric motor is started, the output torque of the electric motor or the driving of the brake corresponding to each of the left and right wheels is controlled independently.

  According to the drive control apparatus of the first to fifth aspects of the present invention, it is possible to reduce the impact caused by the backlash even if the rotation direction of the gear of the reduction gear on the power transmission path changes.

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 can be applied. Vertical section of the drive unit Partial enlarged view of the drive device shown in FIG. The perspective view which shows the state with which the drive device was mounted in the flame | frame. Collinear diagram of the drive unit when the vehicle is stopped Colinear chart of the drive unit when the drive unit is driven forward and travels forward Collinear diagram of the drive device when the drive device is traveling on the coast side and the motor stops A nomographic chart of the drive device when the drive device travels forward on the coast side and the motor regenerates Colinear chart of the drive device when the drive device is on the drive side and travels backward Colinear diagram of the drive unit when the drive unit is traveling on the coast side and traveling backward The figure which showed the state of electric motor 2A, 2B in the driving | running | working state of the vehicle 3, and the state of the separation mechanism The figure which shows schematic structure by the side of the left rear wheel LWr of the drive device 1. Timing chart showing various parameters when the vehicle 3 that has been decelerated at high speed cruise or naturally decelerates The flowchart which shows the content of the control which management ECU9 at the time of an acceleration request | requirement performs The flowchart which shows the content of the other control which management ECU9 at the time of an acceleration request | requirement performs Timing chart showing various parameters when the vehicle 3 shifts from high speed cruise or natural deceleration to deceleration regeneration The flowchart which shows the content of control which management ECU9 at the time of a deceleration request | requirement performs The flowchart which shows the content of the other control which management ECU9 at the time of the deceleration request | requirement performs The flowchart which shows the content of the other control which management ECU9 at the time of the deceleration request | requirement performs The flowchart which shows the control which the drive device 1 performs The block diagram which shows schematic structure of the hybrid vehicle which is other embodiment of the vehicle which can apply a drive device. Longitudinal sectional view of the driving device described in Patent Document 1 The figure which shows an example of the relationship between two gears and backlash which oppose

An embodiment of the present invention will be described below with reference to FIGS.
The drive device 1 according to the present invention uses the electric motors 2A and 2B as drive sources for driving the axles, and is used, for example, in a vehicle 3 having a drive system as shown in FIG.
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 of the vehicle. The power of the drive unit 6 is transmitted via a transmission 7 and a main drive shaft 8. While being transmitted to the front wheel Wf, the power of the drive device 1 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 via a PDU (power drive unit) (not shown), and power supply from the battery and energy regeneration to the battery are performed. This is done via a PDU. The management ECU (MG ECU) 9 controls each operation of the electric motors 2A, 2B and the hydraulic brakes 60A, 60B included in the drive device 1.

  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 3, which are arranged coaxially in the vehicle width direction. Has been. 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. Note that the arrows in FIG. 4 indicate the positional relationship when the drive device 1 is mounted on the vehicle 3.

  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. Resolvers 20A and 20B for feeding back the rotational position information of the rotors 15A and 15B to the management ECU 9 are provided on the outer circumferences on one end side of the cylindrical shafts 16A and 16B and on the end walls 17A and 17B of the speed reducer case 11. Is provided. The management ECU 9 can detect the rotational speeds of the electric motors 2A and 2B based on signals from the resolvers 20A and 20B.

  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. Further, for example, as shown in FIG. 3, the planetary gears 22A and 22B include large-diameter first pinions 26A and 26B that are directly meshed with the sun gears 21A and 21B, and a second pinion having a smaller diameter than the first pinions 26A and 26B. The first and second pinions 26A and 26B and the second pinions 27A and 27B are integrally formed in a state of being coaxially 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 side of the electric motors 2A and 2B (see FIG. 2).

  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 29A and 29B are spline-fitted to an inner race 51 of a one-way clutch (one-way clutch) 50, which will be described later, and the ring gears 24A and 24B are configured to rotate integrally with the inner race 51 of the one-way clutch 50. Yes.

  By the way, a cylindrical space is secured between the speed reducer case 11 and the ring gears 24A and 24B, and hydraulic brakes 60A and 60B that constitute braking means for the ring gears 24A and 24B are provided in the space portions in the first pinion 26A, It wraps in the radial direction with 26B and wraps in the axial direction with the second pinions 27A and 27B. The hydraulic brakes 60A and 60B include a plurality of fixed plates 35A and 35B that are spline-fitted to the inner peripheral surface of a cylindrical outer diameter side support portion 34 that extends in the axial direction on the inner diameter side of the speed reducer case 11, a ring gear 24A, A plurality of rotating plates 36A, 36B that are spline-fitted to the outer peripheral surface of 24B are alternately arranged in the axial direction, and these plates 35A, 35B, 36A, 36B are engaged and released by the annular pistons 37A, 37B. It has become so. The pistons 37 </ b> A and 37 </ b> B are formed between the left and right dividing walls 39 extending from the intermediate position of the reduction gear case 11 to the inner diameter side, and the outer diameter side support portion 34 and the inner diameter side support portion 40 connected by the left and right division walls 39. The pistons 37A and 37B are moved forward by introducing high pressure oil into the cylinder chambers 38A and 38B, and the oil is discharged from the cylinder chambers 38A and 38B. The pistons 37A and 37B are moved backward. The hydraulic brakes 60A and 60B are connected to an oil pump 70 disposed between the support portions 13a and 13b of the frame member 13 described above, as shown in FIG.

More specifically, the pistons 37A and 37B have first piston walls 63A and 63B and second piston walls 64A and 64B in the axial direction, and the piston walls 63A, 63B, 64A and 64B are cylindrical. Are connected by inner peripheral walls 65A and 65B. Therefore, an annular space that opens radially outward is formed between the first piston walls 63A and 63B and the second piston walls 64A and 64B. This annular space is formed on the inner periphery of the outer wall of the cylinder chambers 38A and 38B. It is partitioned forward and backward in the axial direction by partition members 66A and 66B fixed to the surface. A space between the left and right dividing walls 39 of the reduction gear case 11 and the second piston walls 64A and 64B is a first working chamber into which high-pressure oil is directly introduced, and between the partition members 66A and 66B and the first piston walls 63A and 63B. The second working chamber communicates with the first working chamber through the through holes formed in the inner peripheral walls 65A and 65B. The second piston walls 64A and 64B and the partition members 66A and 66B are electrically connected to the atmospheric pressure.
In the hydraulic brakes 60A and 60B, high pressure oil is introduced into the first working chamber and the second working chamber, and the fixing plate 35A and the fixing plate 35A and the second piston walls 64A and 64B are pressurized by the oil pressure acting on the first piston walls 63A and 63B and the second piston walls 64A and 64B. 35B and the rotating plates 36A and 36B can be pressed against each other. Therefore, since the large pressure receiving area can be gained by the first and second piston walls 63A, 63B, 64A, 64B in the front and rear in the axial direction, the fixed plates 35A, 35B A large pressing force against the rotating plates 36A and 36B can be obtained.

  In the case of the hydraulic brakes 60A and 60B, the fixed plates 35A and 35B are supported by the outer diameter side support portion 34 extending from the reduction gear case 11, while the rotation plates 36A and 36B are supported by the ring gears 24A and 24B. When the plates 35A, 35B, 36A, and 36B are pressed by the pistons 37A and 37B, the frictional engagement between the plates 35A, 35B, 36A, and 36B causes a braking force to act on the ring gears 24A and 24B, and the state is fixed. When the engagement by the pistons 37A and 37B is released, the ring gears 24A and 24B are allowed to freely rotate.

  Also, a space is secured between the coupling portions 30A and 30B of the ring gears 24A and 24B facing each other in the axial direction, and only power in one direction is transmitted to the ring gears 24A and 24B in the space to transmit power in the other direction. A one-way clutch 50 is arranged to be shut off. The one-way clutch 50 has a large number of sprags 53 interposed between an inner race 51 and an outer race 52. The inner race 51 is connected to the small diameter portions 29A, 29B of the ring gears 24A, 24B by spline fitting. It is configured to rotate integrally. The outer race 52 is positioned by the inner diameter side support portion 40 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 3 moves forward. More specifically, the one-way clutch 50 is configured to lock or disconnect the ring gears 24A and 24B according to the direction of the torque acting on the ring gears 24A and 24B, and the sun gears 21A and 21B when the vehicle 3 moves forward. When the rotation 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.

  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 reduction gear 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 brakes 60A, 60B, and OWC are A one-way 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 3 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 3 travels forward by the motor torque of the electric motors 2A and 2B of the drive device 1, that is, when the vehicle 3 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 3 is traveling, the ignition is turned on to increase the torque of the electric motors 2A and 2B, whereby the one-way clutch 50 is mechanically engaged and the ring gears 24A and 24B are locked. The vehicle 3 can be started without operating the oil pump 70 that drives 60B. Thereby, the responsiveness at the time of vehicle start can be improved.

  FIG. 7 is a collinear diagram when the motors 2A and 2B are stopped while the vehicle 3 is traveling forward by the drive unit 6, that is, when the drive device 1 is on the coast side and the motors 2A and 2B are stopped. . 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 brakes 60A and 60B, the electric motors 2A and 2B are stopped and the rotation of the electric motors 2A and 2B is prevented. be able to. 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 3 travels 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 coast 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 brakes 60A and 60B and applying the reverse rotation lock torque to the ring gears 24A and 24B, the ring gears 24A and 24B are fixed and the electric motors 2A and 2B have regenerative torque in the reverse rotation direction. Works. Thereby, regenerative charging can be performed by the electric motors 2A and 2B.

  FIG. 9 is a collinear diagram when the vehicle 3 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 brakes 60A and 60B and applying a reverse locking torque 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 move backward. Driving is done. 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 3 is traveling backward by the drive unit 6. 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 state of the electric motors 2A and 2B and the state of the separation mechanism (one-way clutch 50 and hydraulic brakes 60A and 60B) when the vehicle 3 is running. Note that “front” represents the drive unit 6 that drives the front wheel Wf, and “rear” represents the drive device 1 that drives the rear wheel Wr, where ○ is activated (including drive and regeneration), and x is not activated (stopped). Means. The “MOT state” means the state of the electric motors 2 </ b> A and 2 </ b> B of the driving device 1. Furthermore, “OWC” means the one-way clutch 50 and “BRK” means the hydraulic brakes 60A and 60B.

  While the vehicle is stopped, the motors 2A and 2B of the driving device 1 are stopped, and 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 are separated as described with reference to FIG. The mechanism is also inactive.

  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 brakes 60A and 60B are not operated, so the 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 brakes 60A and 60B are 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 brakes 60A and 60B, regenerative charging is performed by the electric motors 2A and 2B.

  In the case of reverse travel (RVS), 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 the rear wheel Wr are driven. This is the four-wheel drive of the side drive device 1. In the case of rear wheel drive, as described in FIG. 9, the motors 2A and 2B rotate in the reverse direction, and the one-way clutch 50 of the separation mechanism is disconnected (OWC free), but the hydraulic brakes 60A and 60B are connected. Thus, the power of the electric motors 2A and 2B is transmitted to the axles 10A and 10B. On the other hand, in the case of four-wheel drive, as described with reference to FIG. 10, 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.

  The motors 2A and 2B of the driving apparatus 1 in the vehicle state shown in FIG. 11 have four types of states: “MOT drive”, “MOT reverse rotation”, “MOT stop”, and “MOT regeneration”. The torque transmission path in each state will be described below. A schematic configuration of the drive device 1 described above on the left rear wheel LWr side is shown in FIG.

(A) When the motors 2A and 2B are in the “MOT drive” state or “MOT reverse rotation” state When the motors 2A and 2B are in “MOT drive”, as shown in FIGS. 6 and 10, the ring gears 24A and 24B Locked by directional clutch 50. When the motors 2A and 2B are “MOT reverse rotation”, the ring gears 24A and 24B are locked by the hydraulic brakes 60A and 60B as shown in FIG. Therefore, torque (drive torque) from the electric motors 2A and 2B is transmitted through the following path. A path in parentheses in the following path indicates a reaction force (reaction) generated because the ring gears 24A and 24B are locked.

“Electric motors 2A, 2B → sun gears 21A, 21B → first pinions 26A, 26B → second pinions 27A, 27B → ring gears 24A, 24B (→ second pinions 27A, 27B) → planetary carriers 23A, 23B → Axle 10A, 10B → rear wheel Wr "

  Thus, during “MOT drive” or “MOT reverse rotation”, torque is transmitted from the sun gears 21A, 21B to the first pinions 26A, 26B of the planetary gears 22A, 22B.

(B) When the motors 2A and 2B are in the “MOT stop” state When the motors 2A and 2B are in the “MOT stop” state, the ring gears 24A and 24B are hydraulically operated by the one-way clutch 50 as shown in FIGS. The brakes 60A and 60B are not locked. Therefore, the torque from the rear wheel Wr of the vehicle 3 is transmitted through the following route.

“Rear wheel Wr → axes 10A, 10B → planetary carriers 23A, 23B → second pinions 27A, 27B of planetary gears 22A, 22B → ring gears 24A, 24B”
Since the ring gears 24A and 24B are not locked, the ring gears 24A and 24B rotate with a very small force. Therefore, most of the torque from the rear wheel Wr is not transmitted to the first pinions 26A and 26B of the planetary gears 22A and 22B, but is transmitted to the ring gears 24A and 24B.

  Thus, during “MOT stop”, torque from the rear wheel Wr is not transmitted to the motors 2A and 2B. Accordingly, the torque is free between the sun gears 21A and 21B and the first pinions 26A and 26B of the planetary gears 22A and 22B.

(C) When the motors 2A, 2B are in the “MOT regeneration” state When the motors 2A, 2B are in “MOT regeneration”, the ring gears 24A, 24B are locked by the hydraulic brakes 60A, 60B as shown in FIG. Therefore, torque (regenerative torque) from the electric motors 2A and 2B is transmitted through the following path. A path in parentheses in the following path indicates a reaction force (reaction) generated because the ring gears 24A and 24B are locked.

“Rear Wheel Wr → Axle 10A, 10B → Planetary Carriers 23A, 23B → Secondary Pinions 27A, 27B of Planetary Gears 22A, 22B → Ring Gears 24A, 24B (→ Second Pinions 27A, 27B) → First Pinions 26A, 26B → Sun Gears 21A, 21B → Motors 2A, 2B "

  Thus, during “MOT regeneration”, torque is transmitted from the first pinions 26A, 26B of the planetary gears 22A, 22B in the direction of the sun gears 21A, 21B.

  As described above, when the motors 2A, 2B are changed from the “MOT stop” state to the “MOT drive” state, the “MOT reverse rotation” state, or the “MOT regeneration” state, the sun gears 21A, 21B and the Torque is transmitted in either direction between the pinions 26A and 26B. When the motors 2A and 2B change from the “MOT drive” state or the “MOT reverse rotation” state to the “MOT regeneration” state, the torque transmission direction between the sun gears 21A and 21B and the first pinions 26A and 26B changes in the reverse direction. . Similarly, when the motors 2A and 2B change from the “MOT regeneration” state to the “MOT drive” state or the “MOT reverse rotation” state, the torque transmission direction between the sun gears 21A and 21B and the first pinions 26A and 26B is reversed. change.

  Engagement between the sun gears 21A and 21B and the first pinions 26A and 26B indicated by dotted ellipses in FIG. 2 is realized by gears facing each other. As described above, a gap called “backlash” is provided between the teeth of the two opposing gears engaged with each other, as shown in FIG. The drive device 1 of the present embodiment performs control so that an impact caused by backlash does not occur when the torque transmission direction changes or when torque is transmitted in any direction from the torque-free state. . Note that torque is transmitted in the same direction (second pinion 27A, 27B → ring gear 24A, 24B) between the second pinions 27A, 27B of the planetary gears 22A, 22B and the ring gears 24A, 24B in any state. There is no need to perform this control.

  Hereinafter, the control performed by the driving device 1 when the electric motors 2A and 2B change from the “MOT stop” state to the “MOT drive” state will be described. (A) When the stopped vehicle 3 starts EV, (b) When the vehicle 3 that has been performing high-speed cruise further accelerates, or (c) When the vehicle 3 that has been naturally decelerated accelerates The electric motors 2A and 2B change from the “MOT stop” state to the “MOT drive” state. The drive device 1 according to the present embodiment performs the control described below when the vehicle 3 is traveling as in (b) and (c) above.

  FIG. 13 is a timing chart showing various parameters at the time when the vehicle 3 that has been speedily cruised or naturally decelerated is accelerating. As shown in FIG. 11, when the vehicle 3 is at high speed cruise or during natural deceleration, the electric motors 2A and 2B of the drive device 1 are stopped. Since the motors 2A and 2B are stopped, the one-way clutch 50 of the separation mechanism is disconnected (OWC free). Further, the hydraulic brakes 60A and 60B are not operated. When the driver makes an acceleration request in this state, the management ECU 9 issues a command to increase the rotation speed (motor rotation speed) of the electric motors 2A and 2B to the target rotation speed Nmr (rotation speed synchronization command).

  Whether or not there is an acceleration request by the driver is determined by the management ECU 9 based on the accelerator pedal opening Ap shown in FIG. Further, the management ECU 9 determines the target rotational speed Nmr based on the vehicle speed or the rotational speeds of the axles 10A and 10B. Further, the vehicle speed is determined by the management ECU 9 based on the signal from the vehicle speed sensor 117 shown in FIG. 1, and the rotational speeds of the axles 10A and 10B are based on the signals from the rotational speed sensors 117a and 117b shown in FIG. The management ECU 9 determines.

  The management ECU 9 controls the electric motors 2A and 2B to output a constant torque when the motor rotational speed increases to a value (Nmr-A) lower than the target rotational speed Nmr by a predetermined value. The management ECU 9 determines that the rotation speed synchronization of the electric motors 2A and 2B has been completed after the electric motors 2A and 2B start control for outputting a constant torque. The timing at which the management ECU 9 determines that the rotation speed synchronization of the electric motors 2A and 2B has been completed is the time when the rotation speed of the electric motors 2A and 2B reaches the target rotation speed Nmr, or the electric motors 2A and 2B output a constant torque. This is the time when a predetermined time has elapsed since the start of control.

  The ring gears 24A and 24B of the planetary gear speed reducers 12A and 12B are locked by the one-way clutch 50 before the management ECU 9 determines that the rotation speed synchronization of the electric motors 2A and 2B has been completed. At this time, the electric motors 2A and 2B output driving torque in a direction in which the one-way clutch 50 is engaged. When the management ECU 9 determines that the rotation speed synchronization of the electric motors 2A and 2B has been completed, the management ECU 9 controls the electric motors 2A and 2B to output the required torque. Thus, the output torque from the electric motors 2A and 2B is transmitted to the rear wheels Wr, and the vehicle 3 is accelerated.

  The control performed by the management ECU 9 described above for the electric motors 2A and 2B of the drive device 1 will be described based on a flowchart. FIG. 14 is a flowchart showing the contents of control performed by the management ECU 9 at the time of acceleration request. As shown in FIG. 14, the management ECU 9 determines whether or not there is an acceleration request from the driver based on the accelerator pedal opening Ap (step S101). If there is an acceleration request, the process proceeds to step S103.

  In step S103, the management ECU 9 detects the rotational speeds of the axles 10A and 10B based on signals from the rotational speed sensors 117a and 117b. Next, the management ECU 9 determines the target rotational speed Nmr based on the rotational speed (step S105). Next, the management ECU 9 issues a command (rotational speed synchronization command) for increasing the rotational speed (motor rotational speed) Nmf of the electric motors 2A and 2B to the target rotational speed Nmr (step S107). The management ECU 9 determines whether the motor rotation speed Nmf has reached a value (Nmr-A) lower than the target rotation speed Nmr by a predetermined value (step S109).

  If the relationship of Nmf ≧ Nmr−A is satisfied, the management ECU 9 controls the motors 2A and 2B so as to output a constant torque T (step S111). Next, the management ECU 9 determines whether the motor rotation speed Nmf has reached the target rotation speed Nmr (step S113). If the relationship of Nmf = Nmr is satisfied, the management ECU 9 determines that the rotation speed synchronization of the electric motors 2A and 2B has been completed (step S115). When the management ECU 9 determines that the rotation speed synchronization of the electric motors 2A and 2B has been completed, the management ECU 9 controls the electric motors 2A and 2B to output the required torque. Therefore, the output torque from the electric motors 2A and 2B is transmitted to the rear wheels Wr, and the vehicle 3 is accelerated.

  In the flowchart of FIG. 14 described above, in step S113, the management ECU 9 determines whether the motor rotational speed Nmf has reached the target rotational speed Nmr. However, as shown in FIG. 15, instead of step S113, the management ECU 9 counts an elapsed time t from the start of control (step S111) in which the electric motors 2A and 2B output a constant torque T (step S214). It may be determined whether the elapsed time t has reached the predetermined time B (step S213).

  As described above, in the present embodiment, when the motors 2A and 2B in a stopped state are driven while the vehicle is running, the rotation speed synchronization control of the motors 2A and 2B is performed, and the motors 2A and 2B The ring gears 24A and 24B are locked by the one-way clutch 50 while a constant torque is being output. When the ring gears 24A and 24B are locked while the output torque of the electric motors 2A and 2B is increasing, the torque (drive torque) is suddenly transmitted from the sun gears 21A and 21B to the first pinions 26A and 26B of the planetary gears 22A and 22B. . In this case, the impact caused by the backlash between the sun gears 21A and 21B and the first pinions 26A and 26B is large. However, as described above, in the present embodiment, since the output torque of the motors 2A and 2B when the ring gears 24A and 24B are locked by the one-way clutch 50 is constant, the sun gears 21A and 21B and the first pinion 26A, The impact due to backlash between 26B is very small.

  When the electric motors 2A and 2B change from the “MOT regeneration” state to the “MOT drive” state, the ring gears 24A and 24B are switched from the lock by the hydraulic brakes 60A and 60B to the lock by the one-way clutch 50, and the sun gears 21A and 21B The direction of torque transmission between the first pinions 26A and 26B is reversed. Similarly at this time, the driving device 1 of the present embodiment performs the control shown in FIG.

  When the stopped vehicle travels backward, the electric motors 2A and 2B change from the “MOT stop” state to the “MOT reverse rotation” state. At this time, an impact caused by backlash may occur. However, as described above, the control performed by the drive device 1 of the present embodiment is performed when the vehicle is traveling. Therefore, when the stopped vehicle travels backward, the drive device 1 does not perform the control.

  Next, the control performed by the drive device 1 when the motors 2A and 2B are changed from the “MOT stop” state to the “MOT regeneration” state will be described. The motors 2A and 2B are switched from the “MOT stop” state to “MOT regeneration” when (a) the vehicle that has been performing high-speed cruise is decelerated and regenerated, or (b) the vehicle that has been naturally decelerated is decelerated and regenerated. It becomes a state.

  FIG. 16 is a timing chart showing various parameters when the vehicle 3 shifts from high-speed cruise or natural deceleration to deceleration regeneration. As shown in FIG. 11, when the vehicle 3 is at high speed cruise or during natural deceleration, the electric motors 2A and 2B of the drive device 1 are stopped. Since the motors 2A and 2B are stopped, the one-way clutch 50 of the separation mechanism is disconnected (OWC free). Further, the hydraulic brakes 60A and 60B are not operated. When the driver makes a deceleration request in this state, the management ECU 9 issues a command to increase the rotation speed (motor rotation speed) of the electric motors 2A and 2B to the target rotation speed Nmr (rotation speed synchronization command).

  The management ECU 9 determines whether or not there is a deceleration request from the driver based on the brake pedal depression force Br shown in FIG. Further, the management ECU 9 determines the target rotational speed Nmr based on the vehicle speed or the rotational speeds of the axles 10A and 10B. Further, the vehicle speed is determined by the management ECU 9 based on the signal from the vehicle speed sensor 117 shown in FIG. 1, and the rotational speeds of the axles 10A and 10B are based on the signals from the rotational speed sensors 117a and 117b shown in FIG. The management ECU 9 determines.

  When the motor rotational speed increases to a value (Nmr-A) lower than the target rotational speed Nmr by a predetermined value, the management ECU 9 issues a drive command for the hydraulic brakes 60A and 60B. In response to the drive command, oil is supplied from the oil pump 70 to the hydraulic brakes 60A and 60B, and the ring gears 24A and 24B of the planetary gear type speed reducers 12A and 12B are locked by the hydraulic brakes 60A and 60B.

  It should be noted that the timing of driving commands of the hydraulic brakes 60A and 60B by the management ECU 9 and the timing at which the ring gears 24A and 24B are locked by the hydraulic brakes 60A and 60B are not simultaneous. That is, it takes time until the ring gears 24A and 24B are locked due to the time required to supply oil from the oil pump 70 to the hydraulic brakes 60A and 60B, the viscosity of the oil, and the like. Therefore, the management ECU 9 determines that the rotation speed synchronization of the electric motors 2A and 2B has been completed after issuing a drive command for the hydraulic brakes 60A and 60B. The timing at which the management ECU 9 determines that the rotation speed synchronization of the electric motors 2A and 2B has been completed is that when the rotation speed of the electric motors 2A and 2B reaches the target rotation speed Nmr, the hydraulic pressure of the hydraulic brakes 60A and 60B has reached a predetermined value. This is the point in time or when a predetermined time has elapsed from the drive command for the hydraulic brakes 60A and 60B.

  When the management ECU 9 determines that the rotation speed synchronization of the electric motors 2A and 2B has been completed, the regenerative torque is applied to the electric motors 2A and 2B in a direction in which the one-way clutch 50 is not engaged. Therefore, in order to maintain the lock of the ring gears 24A and 24B, the management ECU 9 continues to issue a drive command for the hydraulic brakes 60A and 60B even after the determination. Thus, since the locks of the ring gears 24A and 24B by the hydraulic brakes 60A and 60B are maintained, regenerative braking is performed by the electric motors 2A and 2B, and the vehicle 3 decelerates.

  The control performed by the management ECU 9 described above for the electric motors 2A, 2B and the hydraulic brakes 60A, 60B of the drive device 1 will be described based on a flowchart. FIG. 17 is a flowchart showing the contents of control performed by the management ECU 9. As shown in FIG. 17, the management ECU 9 determines whether or not there is a deceleration request from the driver based on the brake pedal depression force Br (step S121). If there is a deceleration request, the process proceeds to step S123.

  In step S123, the management ECU 9 detects the rotational speeds of the axles 10A and 10B based on signals from the rotational speed sensors 117a and 117b. Next, the management ECU 9 determines a target rotational speed Nmr based on the rotational speed (step S125). Next, the management ECU 9 issues a command (rotational speed synchronization command) for increasing the rotational speed (motor rotational speed) Nmf of the electric motors 2A and 2B to the target rotational speed Nmr (step S127). The management ECU 9 determines whether the motor rotation speed Nmf has reached a value (Nmr-A) lower than the target rotation speed Nmr by a predetermined value (step S129). If the relationship of Nmf ≧ Nmr−A is satisfied, the management ECU 9 issues a drive command for the hydraulic brakes 60A and 60B (step S131).

  Next, the management ECU 9 determines whether the motor rotation speed Nmf has reached the target rotation speed Nmr (step S133). If the relationship of Nmf = Nmr is satisfied, the management ECU 9 determines that the rotation speed synchronization of the electric motors 2A and 2B has been completed (step S135). When the management ECU 9 determines that the rotation speed synchronization is completed in step S135, the regenerative torque is applied to the motors 2A and 2B in the direction in which the one-way clutch 50 is not engaged. For this reason, the management ECU 9 continues to issue driving commands for the hydraulic brakes 60A and 60B even after the determination. Therefore, regenerative braking is performed by the electric motors 2A and 2B, and the vehicle 3 is decelerated.

  In the flowchart of FIG. 17 described above, in step S133, the management ECU 9 determines whether the motor rotation speed Nmf has reached the target rotation speed Nmr. However, as shown in FIG. 18, instead of step S133, the management ECU 9 may determine whether the hydraulic pressure Pf of the hydraulic brakes 60A and 60B has reached a predetermined value Pr (step S233). As shown in FIG. 19, instead of step S113, the management ECU 9 counts the elapsed time t from the drive command (step S131) of the hydraulic brakes 60A and 60B (step S334), and the elapsed time t is predetermined. It may be determined whether the time B has been reached (step S333).

  As described above, in the present embodiment, when the motors 2A and 2B in a stopped state are regeneratively driven while the vehicle is running, the rotational speed synchronization control of the motors 2A and 2B is performed, and the hydraulic brakes 60A and 60B. The ring gears 24A and 24B are gradually locked. For this reason, the regenerative torque is gradually transmitted from the first pinions 26A, 26B of the planetary gears 22A, 22B to the sun gears 21A, 21B. The impact caused by backlash between the first pinions 26A and 26B and the sun gears 21A and 21B is very small.

  When the motors 2A and 2B change from the “MOT drive” state to the “MOT regeneration” state, the ring gears 24A and 24B are switched from the lock by the one-way clutch 50 to the lock by the hydraulic brakes 60A and 60B, and the sun gears 21A and 21B. The direction of torque transmission between the first pinions 26A and 26B is reversed. Similarly, at this time, the driving apparatus 1 of the present embodiment performs the control shown in FIG.

  In the present embodiment, the electric motor 2A and the planetary gear type reduction gear 12A of the driving device 1 control the left rear wheel LWr, and the electric motor 2B and the planetary gear type reduction device 12B of the driving device 1 control the right rear wheel RWr. Therefore, when the electric motors 2A and 2B need to be driven while the vehicle 3 is turning, the management ECU 9 makes different torque requests to the left and right electric motors 2A and 2B. That is, the management ECU 9 calculates the required torque for the left and right electric motors 2A, 2B based on the traveling state of the vehicle 3 at this time.

  However, when the vehicle 3 turns, there may be a case where one of the required torques for the left and right electric motors 2A is drive torque and the other is regenerative torque. In this case, the management ECU 9 performs the control shown in FIG. 13 for the electric motor for which the driving torque is requested, and performs the control shown in FIG. 16 for the electric motor for which the regenerative torque is requested. Further, when the management ECU 9 determines that the rotation speed synchronization of the electric motors 2A and 2B has been completed, the management ECU 9 determines whether or not the total value of these two required torques is 0 or more.

  When the total value is 0 or more, the management ECU 9 stops the drive command for the hydraulic brake on the motor side for which the regenerative torque is requested. At this time, regenerative torque is applied to the electric motor in the direction in which the one-way clutch 50 is engaged. For this reason, the ring gear is locked by the one-way clutch 50 even if the lock by the hydraulic brake is released. Therefore, the output torque from the electric motors 2A and 2B is transmitted to the rear wheels Wr, and the vehicle 3 is accelerated. On the other hand, when the total value is less than 0, the management ECU 9 maintains the drive command for the hydraulic brake on the motor side for which the regenerative torque is requested in order to keep the ring gear locked.

  FIG. 20 is a flowchart showing the control performed by the drive device 1. As shown in FIG. 20, the management ECU 9 determines whether or not there is a drive request for the electric motors 2A and 2B (step S151). If there is a drive request, the process proceeds to step S153. In step S153, the management ECU 9 determines whether the traveling of the vehicle 3 is turning based on the steering operation information of the vehicle 3. If the vehicle is turning, the process proceeds to step S171. If the vehicle is traveling straight instead of turning, the process proceeds to step S155.

  In step S155, the management ECU 9 calculates the required torque Tmr for the left and right electric motors 2A, 2B based on the traveling state of the vehicle 3. Next, the management ECU 9 determines whether the required torque Tmr is a power running drive request for the electric motors 2A, 2B (step S157). If it is a power running drive request, the process proceeds to step S159. If it is not a power running drive request but a regenerative drive request, the process proceeds to step S161. In step S159, the management ECU 9 performs the control described with reference to FIG. On the other hand, in step S161, the management ECU 9 performs the control described with reference to FIG. Finally, the management ECU 9 sets the required torque Tmr to the instruction torque Tm (step S163).

  On the other hand, in step S171, the management ECU 9 calculates the required torques Trmr and Tlmr for the left and right electric motors 2A and 2B based on the traveling state of the vehicle 3. Next, the management ECU 9 determines whether both of the required torques Trmr and Tlmr are powering drive requests (step S173). If both the requested torques Trmr and Tlmr are power running drive requests, the process proceeds to step S175. If at least one of them is not a power running drive request but a regenerative drive request, the process proceeds to step S179.

  In step S175, the management ECU 9 performs the control described in FIG. On the other hand, in step S177, the management ECU 9 performs either the control described with reference to FIG. 13 or the control described with reference to FIG. 16 according to the required torque of each electric motor. Next, in step S179, the management ECU 9 determines whether or not the sum of the required torques Trmr and Tlmr is equal to or greater than 0. If the sum is equal to or greater than 0, the management ECU 9 proceeds to step S181. In step S181, the management ECU 9 releases the lock of the hydraulic brake. Finally, in step S183, the management ECU 9 sets the required torques Trmr and Tlmr to the command torques Trm and Tlm.

  The drive device 1 of the present embodiment is provided with two electric motors 2A and 2B and two planetary gear speed reducers 12A and 12B respectively corresponding to the left and right rear wheels Wr. However, as shown in FIG. 21, a configuration in which one electric motor 2 and planetary gear type speed reducer 12 common to the left and right rear wheels Wr may be provided. However, in this case, a differential gear 118 is provided between the electric motor 2 and the axle so that the vehicle 3 can turn.

DESCRIPTION OF SYMBOLS 1 Drive device 2A Electric motor 2B Electric motor 4 Internal combustion engine 5 Electric motor 6 Drive unit 7 Transmission 9 Management ECU
117 Vehicle speed sensors 117a, 117b Rotational speed sensor 10A Axle 10B Axle 11 Reducer case 12A Planetary gear type reducer 12B Planetary gear type reducer 13 Frame member 13a Support part 13b Support parts 16A, 16B Cylindrical shafts 18A, 18B Intermediate wall 20A, 20B Resolver 21A, 21B Sun gear 23A, 23B Planetary carrier 24A, 24B Ring gear 26A, 26B First pinion 27A, 27B Second pinion 33A, 33B Bearing 41A, 41B Bus ring 50 One-way clutch 60A Hydraulic brake 60B Hydraulic brake 70 Oil pump Wf Front wheel LWr Left rear wheel RWr Right rear wheel

Claims (5)

A driving source capable of outputting driving force to the first axle which is one of the front and rear wheel shafts;
An electric motor capable of outputting a driving force to a second axle which is the other of the front and rear wheel shafts;
A speed reducer provided on a power transmission path between the second axle and the electric motor;
A one-way power transmission unit that is provided in series with the speed reducer on the power transmission path, and that transmits a power running driving force from the electric motor to the second axle via the speed reducer;
A brake provided in parallel with the one-way power transmission unit on the power transmission path, and transmitting rotational power from the second axle to the motor via the speed reducer when the motor is driven to regenerate; A vehicle drive control device comprising:
A first detector for detecting the speed of the vehicle or the rotational speed of the second axle;
A target rotational speed determination unit that determines a target rotational speed of the electric motor based on the speed of the vehicle detected by the detection unit or the rotational speed of the second axle;
A second detector for detecting the rotational speed of the electric motor;
When the driving of the electric motor is started in a state where the vehicle is running by the driving force from the driving source, the electric motor is controlled so that the rotational speed of the electric motor is synchronized with the target rotational speed, and the electric motor A control unit for controlling the output torque of the motor or the driving of the brake;
A drive control device comprising: The drive control device according to claim 1,
When the electric motor regeneratively drives the control unit,
When the rotational speed of the electric motor reaches a threshold rotational speed lower than the target rotational speed, the bidirectional power transmission unit is operated. The drive control device according to claim 1 or 2,
When the electric motor drives the power running, the control unit
A drive control device that controls the electric motor to output a predetermined torque when the rotational speed of the electric motor reaches a threshold rotational speed lower than the target rotational speed. The drive control device according to claim 3,
The drive control apparatus according to claim 1, wherein the predetermined torque is a constant torque necessary for the rotation speed of the electric motor to synchronize with the target rotation speed. The drive control device according to any one of claims 1 to 4,
The vehicle is provided with the electric motor, the speed reducer, the brake, and the second axle for each of the left and right wheels provided on the second axle side,
When the control unit starts driving the electric motor in a state where the vehicle is turning and running by the driving force from the driving source, the output torque of the electric motor corresponding to each wheel of the left and right wheels or the A drive control device that controls the drive of a brake independently.

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