JP2017140934A - Drive force control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly transmit drive forces to wheels while properly cooling a rotating electric machine when a temperature of the rotating electric machine is high, in a vehicle having the rotating electric machine which is arranged so as to transmit the drive forces to the wheels.SOLUTION: This drive force control device for a vehicle is employed in the vehicle having: a rotating electric machine MG2 which is arranged so as to transmit drive forces to wheels W; a fluid joint 40 arranged between the wheels and the rotating electric machine; an engagement device CL which can select a full engagement state for connecting an input shaft side and an output shaft side of the fluid joint and a non-full engagement state; and a cooling device for cooling the rotating electric machine by using oil. When a temperature of the rotating electric machine becomes higher than a first prescribed temperature, the drive force control device controls the engagement device to the non-full engagement state, and controls an operation of the rotating electric machine or the other prime motor (for example, an engine 1) so as to prevent the lowering of the drive forces to the wheels from the prime motor caused by the non-full engagement state.SELECTED DRAWING: Figure 1

Description

  The present invention directly connects a rotating electrical machine provided to a wheel so as to be able to transmit a driving force, a fluid coupling disposed between the wheel and the rotating electrical machine, and an input shaft side and an output shaft side of the fluid coupling. The present invention relates to a driving force control device for a vehicle including an engaging device.

  In a vehicle provided with an electric motor provided to transmit a driving force to a wheel and a clutch device capable of interrupting and connecting a power transmission path between the wheel and the electric motor, the power of the motor is high when the temperature of the electric motor is high. It has been proposed to suppress the temperature rise of the electric motor by interrupting the transmission path with a clutch device. For example, Patent Document 1 discloses a vehicle including a rotating electric machine (motor generator) as such an electric motor. The vehicle includes a cooling device configured to supply cooling oil to the rotating electrical machine using an oil pump. In this vehicle, when the temperature of the rotating electrical machine exceeds a predetermined temperature, the rotating electrical machine functions as an electric motor in a state where oil is pumped after the power transmission path between the wheel and the rotating electrical machine is interrupted by the clutch device. It is rotated by being made. As a result, the pumping action caused by the rotation (for example, centrifugal force) of the rotor of the rotating electrical machine increases the amount of oil supplied to the interior of the rotating electrical machine as compared with the case where there is no such pumping action, and the cooling effect of the rotating electrical machine. To increase.

International Publication No. 2012/026044

  In the configuration of the vehicle described in Patent Document 1, the cooling effect by oil can be enhanced by the rotation of the rotating electrical machine. However, since the configuration of Patent Document 1 rotates the rotating electrical machine in a state where the power transmission path between the wheel and the rotating electrical machine is blocked by the clutch device, the driving force is transmitted from the rotating electrical machine to the wheel during the cooling. I can't.

  Accordingly, an object of the present invention is to provide a vehicle equipped with a rotating electrical machine that is capable of transmitting a driving force to a wheel, while appropriately cooling the rotating electrical machine when the temperature of the rotating electrical machine is high and appropriately driving the wheel. Is to communicate.

According to one aspect of the invention,
Direct connection between a prime mover including at least a rotating electrical machine provided to transmit a driving force to a wheel, a fluid coupling disposed between the wheel and the rotating electrical machine, and an input shaft side and an output shaft side of the fluid coupling A driving force control device for a vehicle, comprising: an engaging device that can be selectively set to a fully engaged state and a non-completely engaged state; and a cooling device for cooling the rotating electrical machine using oil. ,
A temperature acquisition unit for acquiring the temperature of the rotating electrical machine;
A non-complete engagement control unit configured to control the engagement device to the non-complete engagement state when the acquired temperature of the rotary electric machine is higher than a first predetermined temperature; 2 a non-complete engagement control unit that controls a non-complete engagement amount of the engagement device so as to be equal to or lower than a predetermined temperature;
When the engagement device is in a non-completely engaged state by the incomplete engagement control unit, the operation of the prime mover is controlled so as to prevent a decrease in driving force from the prime mover to the wheels due to the incomplete engagement. A prime mover operation control unit,
A driving force control apparatus for a vehicle is provided.

  According to the one aspect of the present invention, first, when the temperature of the rotating electrical machine becomes higher than the first predetermined temperature, the engagement device disposed between the wheel and the rotating electrical machine is controlled to the incompletely engaged state. Is done. Therefore, the operating point of the rotating electrical machine can be changed, the heat generation state of the rotating electrical machine itself can be changed, and the rotating electrical machine can be rotated to effectively supply oil to the rotating electrical machine to cool the rotating electrical machine. Further, when the engagement device is in the non-complete engagement state, the operation of the prime mover is controlled so as to prevent the driving force from being reduced from the prime mover to the wheels. However, the driving force can be appropriately transmitted to the wheels. Since the incomplete engagement amount of the engagement device is controlled so that the temperature of the rotating electrical machine becomes equal to or lower than the second predetermined temperature, the rotating electrical machine can be suitably cooled by such a cooling action. Thus, according to the above-described aspect of the present invention, in a vehicle including a rotating electrical machine provided to be able to transmit a driving force to a wheel, the wheel is appropriately cooled when the temperature of the rotating electrical machine is high. An excellent effect that the driving force can be appropriately transmitted to is exhibited.

It is a schematic diagram showing the gear train of the hybrid vehicle which concerns on 1st Embodiment of this invention. It is a control block diagram of the principal part in the vehicle shown in FIG. It is a schematic diagram of the cooling device of the 2nd rotary electric machine of the vehicle shown in FIG. 2 is an operation engagement table showing a relationship between each travel mode and an operation state of each engagement element in the vehicle shown in FIG. 1. FIG. 2 is a collinear diagram related to a single motor EV mode in the vehicle shown in FIG. 1. FIG. 2 is a collinear diagram related to a both-motor EV mode in the vehicle shown in FIG. 1. FIG. 2 is a collinear diagram related to a low-state HV running mode in a parallel mode in the vehicle shown in FIG. 1. FIG. 2 is a collinear diagram related to a high state HV traveling mode in a parallel mode in the vehicle illustrated in FIG. 1. FIG. 2 is a collinear diagram related to an HV traveling mode in a series mode in the vehicle illustrated in FIG. 1. 2 is a flowchart for controlling a clutch that is an engagement device in the vehicle shown in FIG. 1. FIG. 1 is a graph showing the relationship between the temperature of the second rotating electrical machine and the incomplete engagement amount of the clutch in the vehicle. It is a time chart in the vehicle of FIG. 1 in one Example. It is a schematic diagram showing the gear train of the hybrid vehicle which concerns on 2nd Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[First Embodiment]
A first embodiment of the present invention will be described with reference to FIGS. The present embodiment relates to a vehicle driving force control device and is applied to a vehicle as described below.

  As shown in FIG. 1, the vehicle 100 according to the present embodiment is a hybrid (HV) vehicle having an engine 1, a first rotating electrical machine MG1, and a second rotating electrical machine MG2 as a power source, that is, a prime mover. Vehicle 100 may be a plug-in hybrid (PHV) vehicle that can be charged by an external power source. As shown in FIGS. 1 and 2, the vehicle 100 includes an engine 1, a first planetary gear mechanism 10, a second planetary gear mechanism 20, a first rotating electrical machine MG1, a second rotating electrical machine MG2, and a clutch (first clutch) C1. , A clutch (second clutch) CS, a brake B1, a differential gear 30, a fluid coupling 40, a lockup clutch CL as an engagement device, an HV_ECU 50, an MG_ECU 60, and an engine_ECU 70. In particular, a power transmission device TM is incorporated between the engine 1 and the two rotary electric machines MG1 and MG2 and the drive wheels W. The power transmission device TM includes the first planetary gear mechanism 10 and the second planetary gear mechanism 20. , Differential 30, fluid coupling 40, and lockup clutch CL.

  In the vehicle 100 according to the present embodiment, a transmission unit is configured including the first planetary gear mechanism 10, the first clutch C1, and the brake B1. Further, a differential unit is configured including the second planetary gear mechanism 20.

  The engine 1, which is an internal combustion engine, converts the combustion energy of the fuel into a rotational motion of the output shaft and outputs it. The output shaft of the engine 1 is connected to the input shaft 2 of the power transmission device TM. The input shaft 2 is disposed coaxially with the output shaft of the engine 1 and on an extension line of the output shaft. The input shaft 2 is connected to the first carrier 14 of the first planetary gear mechanism 10.

  The first planetary gear mechanism 10 is connected to the engine 1 and is mounted on the vehicle 100 as a first differential mechanism that transmits the rotation of the engine 1. The first planetary gear mechanism 10 is an input-side differential mechanism that is disposed closer to the engine 1 than the second planetary gear mechanism 20. The first planetary gear mechanism 10 is capable of shifting and outputting the rotation of the engine 1. The first planetary gear mechanism 10 is a single pinion type and includes a first sun gear 11, a first pinion gear 12, a first ring gear 13, and a first carrier 14.

  The first ring gear 13 is coaxial with the first sun gear 11 and is disposed on the radially outer side of the first sun gear 11. The first pinion gear 12 is disposed between the first sun gear 11 and the first ring gear 13 and meshes with the first sun gear 11 and the first ring gear 13, respectively. The first pinion gear 12 is rotatably supported by the first carrier 14. The first carrier 14 is connected to the input shaft 2 and rotates integrally with the input shaft 2. Therefore, the first pinion gear 12 can rotate (revolve) around the central axis of the input shaft 2 together with the input shaft 2, and is supported by the first carrier 14 and rotated around the central axis of the first pinion gear 12 ( Rotation) is possible.

  The first clutch C <b> 1 is a clutch device that can connect the first sun gear 11 and the first carrier 14. The first clutch C1 can be, for example, a friction engagement clutch, but is not limited thereto. In the present embodiment, the first clutch C1 is controlled by hydraulic pressure to engage (including complete engagement) or release. The fully engaged first clutch C1 connects the first sun gear 11 and the first carrier 14 and can rotate the first sun gear 11 and the first carrier 14 together. The fully engaged first clutch C <b> 1 regulates the differential of the first planetary gear mechanism 10. On the other hand, the released first clutch C <b> 1 separates the first sun gear 11 and the first carrier 14 and allows relative rotation between the first sun gear 11 and the first carrier 14. That is, the released first clutch C1 allows the differential of the first planetary gear mechanism 10. The first clutch C1 can be controlled to a slip state that is a semi-engaged state. The first clutch C <b> 1 in the slip state allows the differential of the first planetary gear mechanism 10.

  The brake B <b> 1 is a brake device that can regulate the rotation of the first sun gear 11. The brake B1 has an engagement element connected to the first sun gear 11, and an engagement element connected to the vehicle body side, for example, a case of the power transmission device. The brake B1 may be a friction engagement type clutch device similar to the first clutch C1, but is not limited thereto. In the present embodiment, the brake B1 is controlled by hydraulic pressure to engage (including complete engagement) or release. The fully engaged brake B <b> 1 connects the first sun gear 11 and the vehicle body side and can regulate the rotation of the first sun gear 11. On the other hand, the released brake B <b> 1 separates the first sun gear 11 from the vehicle body side and allows the first sun gear 11 to rotate. The brake B1 can be controlled to a slip state that is a semi-engaged state. The brake B1 in the slip state allows the first sun gear 11 to rotate.

  The second planetary gear mechanism 20 of the present embodiment is mounted on the vehicle 100 as a second differential mechanism that connects the first planetary gear mechanism 10 and the drive wheels W. The second planetary gear mechanism 20 is an output-side differential mechanism that is disposed closer to the drive wheel W than the first planetary gear mechanism 10. The second planetary gear mechanism 20 is a single pinion type and includes a second sun gear 21, a second pinion gear 22, a second ring gear 23, and a second carrier 24. The second planetary gear mechanism 20 is disposed coaxially with the first planetary gear mechanism 10 and faces the engine 1 with the first planetary gear mechanism 10 interposed therebetween.

  The second ring gear 23 is coaxial with the second sun gear 21 and is disposed on the radially outer side of the second sun gear 21. The second pinion gear 22 is disposed between the second sun gear 21 and the second ring gear 23 and meshes with the second sun gear 21 and the second ring gear 23, respectively. The second pinion gear 22 is rotatably supported by the second carrier 24. The second carrier 24 is connected to the first ring gear 13 and rotates integrally with the first ring gear 13. The second pinion gear 22 can rotate (revolve) around the central axis of the input shaft 2 together with the second carrier 24, and is supported by the second carrier 24 to rotate (rotate) around the central axis of the second pinion gear 22. It is possible. The first ring gear 13 is an output element of the first planetary gear mechanism 10, and can output the rotation input from the engine 1 to the first planetary gear mechanism 10 to the second carrier 24.

  A rotation shaft 33 of the first rotating electrical machine MG1 is connected to the second sun gear 21. The rotating shaft 33 of the first rotating electrical machine MG1 is disposed coaxially with the input shaft 2 and rotates integrally with the second sun gear 21. A counter drive gear 25 is connected to the second ring gear 23. The counter drive gear 25 is an output gear that rotates integrally with the second ring gear 23. The second ring gear 23 is an output element that can output the rotation input from the first rotating electrical machine MG1 or the first planetary gear mechanism 10 to the drive wheels W.

  The second clutch CS includes the input shaft 2 of the power transmission device TM (that is, the output shaft of the engine 1) coupled to the first carrier 14 of the first planetary gear mechanism 10 and the rotation shaft 33 of the first rotating electrical machine MG1. In other words, the clutch device can be coupled to the rotor of the first rotating electrical machine MG1. The second clutch CS can be, for example, a friction engagement clutch, but is not limited thereto. In the present embodiment, the second clutch CS is controlled by hydraulic pressure to engage (including complete engagement) or release. The fully engaged second clutch CS couples the input shaft 2 and the rotating shaft 33 of the first rotating electrical machine MG1, connects the input shaft 2, the first carrier 14 of the first planetary gear mechanism 10, and the first rotation. The rotating shaft 33 of the electric machine MG1 and the second sun gear 21 can be integrally rotated. On the other hand, the released second clutch CS enables separate driving of the engine 1 and the first rotating electrical machine MG1. The second clutch CS can be controlled to a slip state that is a semi-engaged state.

  The counter drive gear 25 meshes with the counter driven gear 26. The counter driven gear 26 is connected to a drive pinion gear 28 via a fluid coupling 40 to which an input shaft 41 as a counter shaft is connected. The counter driven gear 26 and the drive pinion gear 28 rotate integrally when the lockup clutch CL is engaged. The counter driven gear 26 is engaged with a reduction gear 35. The reduction gear 35 is connected to the rotating shaft 34 of the second rotating electrical machine MG2. That is, the rotation of the second rotating electrical machine MG2 is transmitted to the counter driven gear 26 via the reduction gear 35. The reduction gear 35 has a smaller diameter than the counter driven gear 26, and reduces the rotation of the second rotating electrical machine MG <b> 2 and transmits it to the counter driven gear 26.

  The drive pinion gear 28 meshes with the diffring gear 29 of the differential device 30. The differential device 30 is connected to the drive wheels W via left and right drive shafts 31.

  Here, the above-described fluid coupling 40 and the friction clutch CL included in the power transmission device TM of the present embodiment will be further described.

  An input shaft 41 of the fluid coupling 40 is connected to the counter driven gear 26. An output shaft 42 of the fluid coupling 40 is connected to the drive pinion gear 28. The fluid coupling 40 has a coupling characteristic with respect to the bidirectional rotation of the rotating electrical machines 10 and 20.

  The pump impeller 45 provided on the input shaft 41 of the fluid coupling 40 and the turbine runner 46 provided on the output shaft 42 are connected via a lock-up clutch CL which is an engagement device in the present invention. In the present embodiment, the lockup clutch CL is a friction engagement clutch, but is not limited thereto. The lock-up clutch CL is supplied with pressure oil (hereinafter referred to as lock-up hydraulic pressure) for maintaining the lock-up clutch CL in a fully engaged state except for a predetermined operation state. When in the fully engaged state, the lockup clutch CL directly connects the input shaft 41 side of the fluid coupling 40 and the output shaft 42 side of the fluid coupling 40 to bring the fluid coupling 40 into a directly coupled state. The predetermined operation state described above in the present embodiment includes the time when the temperature of the second rotating electrical machine MG2 is higher than the predetermined temperature, as will be described later, so that the temperature is lowered. For example, when the thermal load of the second rotating electrical machine MG2 is large, the lockup clutch CL is controlled from the fully engaged state to the slip state (out of the incompletely engaged state).

  Thus, the second ring gear 23 is connected to the drive wheel W via the counter drive gear 25, the counter driven gear 26, the fluid coupling 40 with the lock-up clutch CL, the drive pinion gear 28, the differential device 30 and the drive shaft 31. It is connected. The second rotating electrical machine MG2 is connected to a transmission path for driving force between the second ring gear 23 and the driving wheel W, and power (driving force) is applied to the second ring gear 23 and the driving wheel W, respectively. ) Can be transmitted. In particular, the second rotating electrical machine MG <b> 2 is connected to the drive wheel W through the fluid coupling 40, and can transmit a driving force to the drive wheel W through the fluid coupling 40.

  The first rotating electrical machine MG1 and the second rotating electrical machine MG2 each have a function as a motor (electric motor) and a function as a generator. First rotating electrical machine MG1 and second rotating electrical machine MG2 are connected to a battery via an inverter. The first rotating electrical machine MG1 and the second rotating electrical machine MG2 can convert the electric power supplied from the battery into mechanical power and output it, and are driven by the input power to convert the mechanical power into electric power. Can be converted. The electric power generated by the rotating electrical machines MG1 and MG2 can be stored in the battery. As the first rotating electrical machine MG1 and the second rotating electrical machine MG2, for example, an AC synchronous motor generator can be used.

  In the vehicle 100 of the present embodiment, the brake B1, the first clutch C1, the first planetary gear mechanism 10, the counter drive gear 25, the second planetary gear mechanism 20, A first rotating electrical machine MG1 is arranged. The vehicle power transmission device TM of the present embodiment is a multi-shaft type in which the input shaft 2 and the rotation shaft 34 of the second rotating electrical machine MG2 are arranged on different axes.

  Furthermore, in this embodiment, the cooling device 48 for cooling 2nd rotary electric machine MG2 using oil is provided. The cooling device 48 is schematically shown in FIG. The cooling device 48 includes a control valve 48b for controlling the flow of oil to the oil passage 48a formed in the rotating shaft 34 of the rotor MG2_1 of the second rotating electrical machine MG2, and the oil pumped from the oil pump 48c is supplied to the rotor. The MG2_1 and the stator MG2_2 can be supplied. The control valve 48b of the cooling device 48 is controlled to open at least when the second rotating electrical machine MG2 is in a predetermined high temperature state, and its opening degree is lowered to a predetermined temperature range (including a predetermined temperature). Can be controlled. Then, when the control valve 48b is controlled to open as described above, the second rotating electrical machine MG2 is brought into an operating state. Therefore, the oil supplied to the oil passage 48a of the rotating shaft 34 when the control valve 48b is opened flows through the oil passage 48a to reach the rotor MG2_1, and is further connected to the oil passage and formed on the inner peripheral surface of the rotor MG2_1. The axial groove (not shown) flows in the axial direction, and further flows to the stator MG_2 via the radial groove (not shown) of the rotor MG2_1 connected to the axial groove. At this time, since the second rotating electrical machine MG2 is in an operating state, the oil more effectively reaches the rotor MG2_1 and further reaches the stator MG2_2 by the rotational force (centrifugal force) of the rotor MG2_1. Can be cooled. However, the oil pump 48c is, for example, an electric oil pump that operates with electric power supplied from a battery, but may be a mechanical oil pump (for example, operated with the rotation of the wheel W). The detailed configuration of such a cooling device 48 will be apparent to those skilled in the art from Patent Document 1, and variations thereof will be apparent from Patent Document 1.

  As shown in FIG. 2, vehicle 100 includes HV_ECU 50, MG_ECU 60, and engine_ECU 70. Each ECU 50, 60, 70 is an electronic control unit having a computer. The HV_ECU 50 has a function of integrally controlling the entire vehicle 100. The MG_ECU 60 and the engine_ECU 70 are electrically connected to the HV_ECU 50, respectively. The HV_ECU 50, the MG_ECU 60, and the engine_ECU 70 are substantially configured as one electronic control unit (control device) as a whole, and may be configured as an integrated unit device from the beginning.

  The MG_ECU 60 can control the first rotating electrical machine MG1 and the second rotating electrical machine MG2. For example, the MG_ECU 60 adjusts the current value supplied to the first rotating electrical machine MG1, controls the output torque of the first rotating electrical machine MG1, and adjusts the current value supplied to the second rotating electrical machine MG2. The output torque of the second rotating electrical machine MG2 can be controlled.

  The engine_ECU 70 can control the engine 1. The engine_ECU 70 can, for example, control the opening of the electronic throttle valve of the engine 1, perform ignition control of the engine 1 by outputting an ignition signal, and perform fuel injection control on the engine 1. The engine_ECU 70 can control the output torque of the engine 1 by electronic throttle valve opening control, injection control, ignition control, and the like.

  The HV_ECU 50 is connected to a vehicle speed sensor, an accelerator opening sensor, an MG1 rotational speed sensor, an MG2 rotational speed sensor, an output shaft rotational speed sensor, a battery sensor, an MG2 temperature sensor, and the like. By these sensors, the HV_ECU 50 corresponds to the vehicle speed, the accelerator opening, the rotational speed of the first rotating electrical machine MG1, the rotational speed of the second rotating electrical machine MG2, and the output shaft of the power transmission device TM (that is, the input shaft 41 of the fluid coupling 40). The counter shaft), battery state SOC, MG2 temperature, and the like.

  The HV_ECU 50 can calculate a required driving force, required power, required torque, and the like for the vehicle 100 based on the acquired information. The HV_ECU 50 determines the output torque (MG1 torque) of the first rotating electrical machine MG1, the output torque (MG2 torque) of the second rotating electrical machine MG2 and the output torque (engine torque) of the engine 1 based on the calculated request value. The total output torque (output torque) by them is determined. The HV_ECU 50 outputs the MG1 torque command value and the MG2 torque command value to the MG_ECU 60. Further, the HV_ECU 50 outputs an engine torque command value to the engine_ECU 70.

  The HV_ECU 50 controls the first clutch C1, the second clutch CS, the brake B1, and the lockup clutch CL, respectively, based on a travel mode described later. The HV_ECU 50 provides a command value for the supply hydraulic pressure (engagement pressure) PbC1 for the first clutch C1, a command value for the supply hydraulic pressure (engagement pressure) PbCS for the second clutch CS, and a command for the supply hydraulic pressure (engagement hydraulic pressure) PbB1 for the brake B1. And the command value of the supply hydraulic pressure (engagement pressure) PbCL for the lockup clutch CL are output. A hydraulic control device (not shown) controls the supply hydraulic pressure to each of the clutches C1, CS, CL and the brake B1 according to the command values of the engagement hydraulic pressures PbC1, PBCS, PbB1, PBCL.

  The vehicle 100 can selectively execute hybrid (HV) traveling or EV traveling. The HV travel is a travel mode in which the vehicle 100 travels using the engine 1 as a power source. In HV traveling, in addition to the engine 1, the second rotating electrical machine MG2 may be used as a power source. The EV traveling is a traveling mode in which traveling is performed using at least one of the first rotating electrical machine MG1 and the second rotating electrical machine MG2 as a power source. In EV traveling, it is possible to travel with the engine 1 stopped.

  In the present embodiment, the vehicle 100 uses the second rotating electrical machine MG2 as a single power source as the EV driving mode, the single motor EV mode for driving the vehicle 100, and the first rotating electrical machine MG1 and the second rotating electrical machine MG2 as the power source. As a both-motor EV mode in which the vehicle 100 travels. Hereinafter, these modes will be described with reference to FIGS. However, in the following description of FIGS. 4 to 9, description of the lockup clutch CL in the fully engaged state is omitted.

  In the engagement table of FIG. 4, the circles in the column of the clutch C1, the column of the brake B1, and the column of the clutch CS indicate engagement, and the blank column indicates release. Further, the triangle mark indicates that either the clutch C1 or the brake B1 is engaged and the other is released. The single motor EV mode is executed, for example, by releasing both the clutch C1 and the brake B1.

  FIG. 5 is a collinear diagram related to the single motor EV mode. In the alignment chart, reference numerals S1, C1, and R1 indicate the first sun gear 11, the first carrier 14, and the first ring gear 13, respectively. Reference numerals S2, C2, and R2 indicate the second sun gear 21 and the second carrier 24, respectively. The 2nd ring gear 23 is shown.

  In the single motor EV mode, the clutch C1, the brake B1, and the clutch CS are released. When the brake B1 is released, the rotation of the first sun gear 11 is allowed, and when the clutch C1 is released, the first planetary gear mechanism 10 can be differentiated. The HV_ECU 50 causes the second rotating electrical machine MG2 to output a positive torque via the MG_ECU 60 to cause the vehicle 100 to generate a driving force in the forward direction. The second ring gear 23 rotates forward in conjunction with the rotation of the drive wheel 32. Here, the normal rotation is the rotation direction of the second ring gear 23 when the vehicle 100 moves forward. The HV_ECU 50 operates the first rotating electrical machine MG1 as a generator to reduce drag loss. Specifically, the HV_ECU 50 applies a slight torque to the first rotating electrical machine MG1 to generate electric power, and sets the rotational speed of the first rotating electrical machine MG1 to zero. Thereby, the drag loss of the first rotating electrical machine MG1 can be reduced. Further, even when the MG1 torque is set to 0, the MG1 torque may not be applied if the MG1 rotation speed can be maintained at 0 using the cogging torque. Alternatively, the MG1 rotation speed may be set to 0 by d-axis locking of the first rotating electrical machine MG1.

  The first ring gear 13 rotates along with the second carrier 24 and rotates forward. In the first planetary gear mechanism 10, since the clutch C1 and the brake B1 are in a neutral state, the engine 1 is not rotated and the first carrier 14 stops rotating. Therefore, it is possible to increase the amount of regeneration. The first sun gear 11 idles and rotates negatively. The neutral state of the first planetary gear mechanism 10 is a state in which no power is transmitted between the first ring gear 13 and the first carrier 14, that is, the engine 1 and the second planetary gear mechanism 20 are disconnected. In this state, power transmission is interrupted. The first planetary gear mechanism 10 is connected to connect the engine 1 and the second planetary gear mechanism 20 when at least one of the clutch C1 and the brake B1 is engaged.

  When traveling in the single motor EV mode, the battery may be fully charged and regenerative energy may not be obtained. In this case, it is conceivable to use an engine brake together. By engaging the clutch C <b> 1 or the brake B <b> 1, the engine 1 can be connected to the drive wheel W and the engine brake can be applied to the drive wheel 32. As shown by a triangle in FIG. 4, when the clutch C1 or the brake B1 is engaged in the single motor EV mode, the engine 1 is brought into a rotating state, and the engine speed is increased by the first rotating electrical machine MG1 to be in an engine braking state. be able to.

  In the both-motor EV mode, the HV_ECU 50 engages the clutch C1 and the brake B1 (the clutch SC is released). FIG. 6 is a collinear diagram related to the both-motor EV mode. When the clutch C1 is engaged, the differential of the first planetary gear mechanism 10 is restricted, and when the brake B1 is engaged, the rotation of the first sun gear 11 is restricted. Accordingly, the rotation of all the rotating elements of the first planetary gear mechanism 10 is stopped. By restricting the rotation of the first ring gear 13 that is the output element, the second carrier 24 connected thereto is locked at zero rotation.

  The HV_ECU 50 causes the first rotary electric machine MG1 and the second rotary electric machine MG2 to output driving driving torque, respectively. Since the rotation of the second carrier 24 is restricted, the second carrier 24 can take a reaction force against the torque of the first rotating electrical machine MG <b> 1 and output the torque of the first rotating electrical machine MG <b> 1 from the second ring gear 23. The first rotating electrical machine MG1 can output a positive torque from the second ring gear 23 by outputting a negative torque and rotating negatively when moving forward. On the other hand, at the time of reverse travel, the first rotating electrical machine MG1 can output negative torque from the second ring gear 23 by outputting positive torque and rotating forward.

  In HV traveling, there are a parallel mode and a series mode. First, the parallel mode will be described. In the HV traveling in the parallel mode, the second planetary gear mechanism 20 is basically in a differential state, and the first planetary gear mechanism 10 of the transmission unit is switched between low and high. FIG. 7 is a collinear diagram related to the HV traveling mode in the low state (HV low mode) in the HV traveling in the parallel mode, and FIG. 8 is the HV traveling mode in the high state (HV high in the HV traveling in the parallel mode). FIG.

  In the HV low mode, the HV_ECU 50 engages the clutch C1 and releases the brake B1 (releases the clutch CS). When the clutch C1 is engaged, the differential of the first planetary gear mechanism 10 is restricted, and the first sun gear 11, the first ring gear 13, and the first carrier 14 of the first planetary gear mechanism 10 rotate integrally. Therefore, the rotation of the engine 1 is not accelerated or decelerated and is transmitted from the first ring gear 13 to the second carrier 24 at a constant speed.

  On the other hand, in the HV high mode, the HV_ECU 50 releases the clutch C1 and engages the brake B1 (releases the clutch CS). The engagement of the brake B1 restricts the rotation of the first sun gear 11. Therefore, the first planetary gear mechanism 10 enters an overdrive (OD) state in which the rotation of the engine 1 input to the first carrier 14 is increased and output from the first ring gear 13. Thus, the first planetary gear mechanism 10 can increase the rotation of the engine 1 and output it.

  As described above, the clutch C1 and the brake B1 switch the first planetary gear mechanism 10 by switching between the state in which the differential of the first planetary gear mechanism 10 is regulated and the state in which the differential of the first planetary gear mechanism 10 is allowed. It is arranged and configured to change speed. The power transmission device TM of the vehicle 100 can be switched between the HV high mode and the HV low mode by the transmission unit including the first planetary gear mechanism 10, the clutch C1, and the brake B1, and improves the transmission efficiency of the vehicle 100. Can do. Further, a second planetary gear mechanism 20 as a differential unit is connected in series with the rear stage of the transmission unit. Since the first planetary gear mechanism 10 is overdriven, there is an advantage that the first rotating electrical machine MG1 does not have to be greatly increased in torque.

  For example, the HV_ECU 50 selects EV traveling in a low load traveling region where the vehicle speed is low and the required driving force is small. In the EV travel range, for example, the single motor EV mode is selected when the load is low, and the dual motor EV mode is selected when the load is high. The region of higher vehicle speed and higher load than the EV traveling region is the HV traveling region. The HV_ECU 50 selects the HV low mode in the middle and low vehicle speed and high load regions of the HV traveling region, and selects the HV high mode in the high vehicle speed and low load region. The fuel consumption can be improved by overdriving the transmission at high vehicle speed and low load.

  Next, HV traveling in the series mode will be described. FIG. 9 is a collinear diagram related to the HV travel mode (HV series mode) in the series mode. In the series mode, the HV_ECU 50 releases the clutch C1 and the brake B1 and engages the second clutch CS. Engaging the second clutch CS connects the engine 1 to the first rotating electrical machine MG1. Thereby, electric power is generated by the first rotating electrical machine MG1, and the motor traveling by the second rotating electrical machine MG2 is enabled.

  Now, in the vehicle having the above configuration, when the temperature of the second rotating electrical machine MG2 is high, the temperature rise is suppressed, and the temperature is maintained in the temperature range suitable for the second rotating electrical machine MG2, or even within the temperature range. The control valve 48b of the cooling device 48 is opened (in the operating state of the oil pump 48c) so as to lower.

  Further, in the vehicle 100 of the present embodiment, when the temperature of the second rotating electrical machine MG2 is high, the lock-up clutch CL is slipped or released to promote cooling of the second rotating electrical machine MG2. Hereinafter, the control of the lockup clutch CL will be described with reference to the flowchart of FIG. Note that the flowchart of FIG. 10 is repeated at predetermined time intervals at least when the second rotating electrical machine MG2 is in the operating state.

  In step S101, the HV_ECU 50 determines whether or not the temperature of the second rotating electrical machine MG2 is higher than a predetermined temperature and the output torque of the second rotating electrical machine MG2 is equal to or lower than the predetermined torque. The temperature of the second rotating electrical machine MG2 is obtained by acquiring the output (for example, output value, detection value) of the MG2 temperature sensor by the temperature acquisition unit of the HV_ECU 50. And the temperature determination part of HV_ECU50 determines whether the temperature of 2nd rotary electric machine MG2 is higher than predetermined temperature. Further, the MG2 torque determination unit of the HV_ECU 50 determines whether or not the output torque of the second rotating electrical machine MG2 determined as described above is equal to or less than a predetermined torque. If both of these determination units make an affirmative determination, an affirmative determination is made in step S101. The temperature determination unit may be provided integrally with the MG2 torque determination unit. Further, in the present embodiment, both the temperature of the second rotating electrical machine MG2 and the output torque of the second rotating electrical machine MG2 are set as determination targets in step S101, but only one of these may be determined. Good. For example, when the temperature of the second rotating electrical machine MG2 is higher than a predetermined temperature, an affirmative determination may be made in step S101 (regardless of the output torque of the second rotating electrical machine MG2). The determination as to whether or not the temperature of the second rotating electrical machine MG2 is higher than the predetermined temperature is a determination as to whether or not the temperature of the second rotating electrical machine MG2 is in a predetermined high temperature state. It may be set in advance based on experiments in order to ensure efficient operation and safe operation of the electric machine MG2. Further, whether or not the output torque of the second rotating electrical machine MG2 is equal to or lower than the predetermined torque is determined by the second rotating electrical machine MG2 itself, rather than the cooling effect due to the increase in the rotational speed of the second rotating electrical machine MG2 by the incomplete engagement control described later. In the operating state in which the increase in the heat generation amount due to the increase in loss exceeds the incomplete engagement control, the predetermined torque is set based on experiments in advance under such a technical idea. Good.

  Since the temperature of the second rotating electrical machine MG2 is equal to or lower than the predetermined temperature, or the output torque of the second rotating electrical machine MG2 is larger than the predetermined torque, if a negative determination is made in step S101, the process proceeds to step S103 and goes through step S103. Then the routine ends. In step S103, a complete engagement control mode for setting the lockup clutch CL in a fully engaged state is set. That is, when arriving at step S103, the HV_ECU 50 applies the hydraulic pressure necessary to bring the clutch CL into the fully engaged state as the command value of the supply hydraulic pressure (engagement pressure) PbCL for the lockup clutch CL. Output a signal. Thereby, the operation of the control valve and / or the oil pump for supplying such hydraulic pressure to the lock-up clutch CL is controlled. Thus, unless the cooling condition in step S101 is satisfied, in principle, the lockup clutch CL is brought into a fully engaged state.

  Since the temperature of the second rotating electrical machine MG2 is higher than the predetermined temperature and the output torque of the second rotating electrical machine MG2 is equal to or lower than the predetermined torque, if an affirmative determination is made in step S101, the process proceeds to step S105 and goes through step S105. Then the routine ends. In step S105, an incomplete engagement control mode for setting the lockup clutch CL in an incomplete engagement state is set. That is, when the incomplete engagement control mode is set up to step S105, the incomplete engagement control unit of the HV_ECU 50 uses the clutch CL as the command value of the supply hydraulic pressure (engagement pressure) PbCL for the lockup clutch CL. A signal for applying a hydraulic pressure to the clutch CL to make a fully engaged state (including a radius engagement state, that is, a slip state and a release state) is output. Thereby, the operation of the control valve and / or the oil pump of the hydraulic control circuit for supplying such hydraulic pressure to the lockup clutch CL is controlled.

  Here, when the lockup clutch CL is controlled to the incompletely engaged state, in principle, the hydraulic pressure supplied to the lockup clutch CL is controlled based on the relationship shown in FIG. FIG. 11 shows the relationship between the temperature of the second rotating electrical machine MG2 on the horizontal axis and the incomplete engagement amount (also referred to as slip amount) of the lockup clutch CL on the vertical axis. In the horizontal axis, the temperature of the second rotating electrical machine MG2 is higher toward the right side in FIG. 11, and the incomplete engagement amount is smaller toward the lower side in FIG. 11 on the vertical axis (the incomplete engagement amount is zero). Means that the lock-up clutch CL is in a fully engaged state, and the incomplete engagement amount is infinite or maximum means that the lock-up clutch CL is in a released state).

  In FIG. 11, the temperature TA on the horizontal axis corresponds to the predetermined temperature in step S101. When the temperature of the second rotating electrical machine MG2 is equal to or lower than the predetermined temperature TA, the incomplete engagement amount of the lockup clutch CL is set to zero, that is, a complete engagement state is established. Then, as the temperature of the second rotating electrical machine MG2 becomes higher than the predetermined temperature TA as a reference, the incomplete engagement amount increases proportionally. The relationship between the temperature of the second rotating electrical machine MG2 and the incomplete engagement amount of the lockup clutch CL is set based on experiments in advance according to the characteristics of the second rotating electrical machine MG2, and stored in the storage unit of the HV_ECU 50. It is good to be. Note that the relationship between the temperature of the second rotating electrical machine MG2 and the incomplete engagement amount of the lockup clutch CL is not limited to change proportionally, and can be set in various ways, for example, variable in steps. Also good.

  The incomplete engagement amount of the lockup clutch CL when the incomplete engagement control mode is set may be variable. The incomplete engagement amount may be changed based on the relationship of FIG. 11 so as to lower the temperature of the second rotating electrical machine MG2 to a predetermined temperature TA or less according to the acquired temperature of the second rotating electrical machine MG2. it can.

  However, the variable control of the incomplete engagement amount can be executed based on various logics. For example, when the temperature of the second rotating electrical machine MG2 has converged to a certain temperature and no further temperature increase has occurred, variable control of the incomplete engagement amount is executed to reduce the incomplete engagement amount stepwise. Can.

  For example, the variable control of the incomplete engagement amount may be so-called feedback control so that the temperature is lowered to a target temperature TA or less according to the acquired temperature of the second rotating electrical machine MG2. Good. Specifically, when the lockup clutch CL is in the fully engaged state, when the process first reaches step S105, the initial incomplete engagement amount of the lockup clutch CL is set based on the relationship of FIG. The hydraulic pressure is controlled such that the hydraulic pressure corresponding to the initial incomplete engagement amount is supplied to the lockup clutch CL. Thereafter, the HV_ECU 50 is locked so that the temperature of the second rotating electrical machine MG2 becomes equal to or lower than the predetermined temperature TA according to the temperature increasing degree of the second rotating electrical machine MG2 (for example, the rate of temperature increase per unit time (rising speed)). The supply hydraulic pressure of the up clutch CL can be controlled. For example, when the degree of increase in the temperature of the second rotating electrical machine MG2 decreases with an increase in the incomplete engagement amount, control for reducing the incomplete engagement amount can be performed.

  Further, the predetermined temperature for determination (first predetermined temperature) TA in step S101 is the same as the target temperature (second predetermined temperature) during incomplete engagement control in the above embodiment, but incomplete engagement control. It may be different from the target temperature inside. In this case, the target temperature during the incomplete engagement control may be lower than the predetermined temperature for determination in step S101. In addition, the target temperature of the second rotating electrical machine during the incomplete engagement control is not limited to the predetermined temperature, and may be a predetermined temperature range. For example, a temperature range that is a temperature range lower than the first predetermined temperature and includes a second predetermined temperature (lower than the first predetermined temperature) may be set as the predetermined temperature range. In this case, after the temperature of the second rotating electrical machine has dropped to the second predetermined temperature or less, the incomplete engagement of the lockup clutch CL is maintained so that the temperature of the second rotating electrical machine is maintained in a predetermined temperature range for a predetermined time. The total amount may be controlled. By setting the target temperature (second predetermined temperature) and the predetermined temperature range during such incomplete engagement control according to the characteristics of the second rotating electrical machine MG2, excessive cooling of the second rotating electrical machine MG2 is prevented. Thus, it is possible to maintain the temperature of the second rotating electrical machine MG2 at a temperature at which the operation suitably occurs.

  Thus, when the lockup clutch CL is in a non-completely engaged state so as to lower the temperature of the second rotating electrical machine MG2, the driving force transmitted to the output shaft 42 via the fluid coupling 40 Changes (eg, decreases). In order to prevent the driving force transmitted to the wheels from being reduced due to the incomplete engagement of the lock-up clutch CL, the prime mover operation control unit of the HV_ECU 50 determines the first rotating electrical machine MG1 according to the operation mode at that time. At least one of the output torque, the output torque of the second rotating electrical machine MG2, and the output torque of the engine 1 is determined, and at least one operation thereof is controlled. Accordingly, it is possible to prevent the driver or the like from feeling uncomfortable due to the change in the driving force of the wheels. Note that the output torque of the first rotating electrical machine MG1, the output torque of the second rotating electrical machine MG2, and the output of the engine 1 are prevented so that the driving force transmitted to the wheels is not reduced due to slipping or releasing of the lockup clutch CL. In determining at least one of the torques, at least one of the set incomplete engagement amount of the lockup clutch CL, the set supply hydraulic pressure, and the temperature of the second rotating electrical machine MG2 can be used.

  Here, vehicle driving force control as an example will be described with reference to FIG. FIG. 12 is a time chart showing changes in various values when the temperature of the second rotating electrical machine MG2 becomes higher than a predetermined temperature in the HV low mode described above. Since the HV low mode is set, the clutch C1 is engaged and the brake B1 is released (in FIG. 12, the supply hydraulic pressures (C1 hydraulic pressure and B1 hydraulic pressure) at this time are shown as constant values). .

  In FIG. 12, the temperature of the second rotating electrical machine MG2 continues to rise with time t1, t2 and the passage of time. However, the temperature of the second rotating electrical machine MG2 is still below the predetermined temperature TA. Until time t2, the output torque (MG2 torque) of the second rotating electrical machine MG2 is equal to or less than the predetermined torque TB. Therefore, at time t2, the supply hydraulic pressure (CL hydraulic pressure) of the friction clutch CL is a hydraulic pressure corresponding to the fully engaged state (No determination in step S101, step S103).

  At time t3, the output torque of the second rotating electrical machine MG2 is equal to or lower than the predetermined torque TB. However, since the temperature of the second rotating electrical machine MG2 has become higher than the predetermined temperature TA (affirmative determination in step S101), the lockup clutch CL Non-complete engagement control is started (step S105). Thereby, the supply hydraulic pressure (CL hydraulic pressure) of the lockup clutch CL starts to decrease according to the relationship of the graph of FIG. Note that, from time t3 to time t4, the temperature of the second rotating electrical machine MG2 rises, so the supply hydraulic pressure of the lockup clutch CL continues to fall. Along with this, the rotational resistance decreases, the rotational speed of the second rotating electrical machine MG2 (MG2 rotational speed) starts to increase, and the torque of the second rotating electrical machine MG2 decreases. When the supply hydraulic pressure of the lock-up clutch CL decreases, the operating point of the second rotating electrical machine MG2 changes and the heat generation state of the second rotating electrical machine changes. Furthermore, the oil flow by the cooling device 48 of the second rotating electrical machine is promoted by the increase in the rotational speed of the second rotating electrical machine MG2, and the cooling effect can be enhanced. Therefore, the second rotating electrical machine MG2 can be cooled. Therefore, the further temperature rise of the second rotating electrical machine MG2 is suppressed (the degree of increase becomes moderate) and converges to a certain temperature (see the change in the MG2 temperature at times t3 to t4 to t5 in FIG. 12).

  When the lock-up clutch CL is brought into a non-complete engagement state, the engine is compensated for non-complete engagement of the lock-up clutch CL, that is, torque reduction (loss torque) due to slip or release thereof, and prevents a decrease in output torque. 1 torque increase control is executed. The torque increase control may be, for example, fuel injection amount increase control or throttle valve opening increase control. In order to control the engine speed accompanying the increase in the torque of the engine 1, control for reducing the torque of the first rotary electricity MG1 is executed. Note that the decrease in the rotation speed (MG1 rotation speed) of the first rotating electricity MG1 at time t3 is due to the increase in the rotation speed of the second ring R2 due to the incomplete engagement of the lockup clutch CL. By such control, even if incomplete engagement control of the lockup clutch CL is started at time t3, the output torque can be kept substantially constant thereafter (outputs at times t3 to t4 in FIG. 12). Torque reference). As described above, during the period from time t3 to time t4, the incomplete engagement amount of the lockup clutch CL increases with the temperature rise of the second rotating electrical machine MG2 (see FIG. 11). Thereby, as described above, cooling of the second rotating electrical machine MG2 is promoted.

  At time t4, although not shown, the required torque (corresponding to the output torque in FIG. 12) is increased by the driver depressing the accelerator pedal, and therefore engine torque increase control is further executed. Along with this, an increase in torque of the second rotating electrical machine MG2 and a decrease in torque of the first rotating electrical machine MG1 occur. It should be noted that the rotational speed of the first rotating electrical machine MG1 decreases (according to the increase in the rotational speed of the second ring gear) as the vehicle speed increases as the driver depresses the accelerator pedal, and the second rotating electrical machine MG2 The number of revolutions increases. Such control continues similarly at time t5. Note that, from time t4 to time t5, the temperature of the second rotating electrical machine MG2 is substantially constant, so that the oil pressure of the lockup clutch CL is substantially constant.

  At time t4, the torque of the second rotating electrical machine MG2 begins to increase because of the above control for compensating for the torque loss due to the incomplete engagement of the lockup clutch CL and the acceleration request by the driver (depressing the accelerator pedal). Operation). Since the torque of the second rotating electrical machine MG2 exceeds the predetermined torque TB at time t5 (determination is negative in step S101), the hydraulic pressure of the lockup clutch CL is on the fully engaged side with a slope that does not cause a shock here. To increase. Even when the lock-up clutch CL reaches the fully engaged state at time t6, the temperature of the second rotating electrical machine MG2 is higher than the predetermined temperature TA because the torque of the second rotating electrical machine MG2 thus exceeds the predetermined torque TB. It is. That is, for example, when there is no acceleration request from the driver, the torque of the second rotating electrical machine MG2 can be shifted below the predetermined torque TB, so the temperature of the second rotating electrical machine MG2 becomes the predetermined temperature TA or lower. The lockup clutch CL can be controlled to the non-completely engaged state. In FIG. 12, after the time t6, the rotation speed of the second rotating electrical machine MG2 increases due to a further acceleration request from the driver, the oil flow rate increases, and the cooling action is promoted, and the second rotating electrical machine MG2 Since the operating point is changed and the loss of the second rotating electrical machine MG2 is suppressed, the temperature of the second rotating electrical machine MG2 has dropped below the predetermined temperature TA after time t6.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. The second embodiment is mainly different from the first embodiment in the arrangement of the fluid coupling 40 with the lockup clutch CL. Therefore, only the arrangement of the fluid coupling 40 will be described based on FIG. 13, and description of the second embodiment including other controls will be omitted. In the second embodiment as well, elements having the same functions as those already described in the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  In the first embodiment described above, the second planetary gear mechanism 20 and the second rotating electrical machine MG2 are connected in parallel to the input shaft 41 of the fluid coupling 40, and the output shaft 42 of the fluid coupling 40 is connected to the drive wheel W side. Connected. However, in the second embodiment, the input shaft 41 of the fluid coupling 40 is directly connected to the second rotating electrical machine MG2. In this way, the fluid coupling 40 can affect only the torque transmission of the second rotating electrical machine MG2. Therefore, the transmission torque of the fluid coupling 40 is reduced, and incomplete engagement control of the lockup clutch CL of the fluid coupling 40 is facilitated.

  In the second embodiment, the rotor MG2_1 of the second rotating electrical machine MG2 is connected to the input shaft 41b of the fluid coupling 40, and the output shaft 42 of the fluid coupling 40 is connected to the reduction gear 35. The counter driven gear 26 is connected to the drive pinion gear 28 via the counter shaft 150.

  In the two embodiments described above, the prime mover is constituted by one engine 1 and two rotary electric machines MG1 and MG2. However, the present invention is applied to a vehicle having a structure including at least the rotary electric machine corresponding to the second rotary electric machine as the prime mover. It is also possible to apply.

  Embodiments of the present invention are not limited to the embodiments described above. All modifications, applications, and equivalents included in the spirit of the present invention defined by the claims are included in the present invention.

1 Engine MG1 First rotating electrical machine MG2 Second rotating electrical machine 40 Fluid coupling CL Lock-up clutch (engaging device)

Claims (1)

Direct connection between a prime mover including at least a rotating electrical machine provided to transmit a driving force to a wheel, a fluid coupling disposed between the wheel and the rotating electrical machine, and an input shaft side and an output shaft side of the fluid coupling A driving force control device for a vehicle, comprising: an engaging device that can be selectively set to a fully engaged state and a non-completely engaged state; and a cooling device for cooling the rotating electrical machine using oil. ,
A temperature acquisition unit for acquiring the temperature of the rotating electrical machine;
A non-complete engagement control unit configured to control the engagement device to the non-complete engagement state when the acquired temperature of the rotary electric machine is higher than a first predetermined temperature; 2 a non-complete engagement control unit that controls a non-complete engagement amount of the engagement device so as to be equal to or lower than a predetermined temperature;
When the engagement device is in a non-completely engaged state by the incomplete engagement control unit, the operation of the prime mover is controlled so as to prevent a decrease in driving force from the prime mover to the wheels due to the incomplete engagement. A prime mover operation control unit,
Driving force control device for a vehicle.

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