Hybrid vehicle system

1. A hybrid vehicle system comprising:

an engine that is capable of outputting a torque to be transmitted to a driving wheel;

a first motor generator that is provided in a coupled manner to the engine and that is capable of outputting a torque to be transmitted to the driving wheel;

a transmission that converts a torque output from one or both of the engine and the first motor generator at a predetermined transmission gear ratio;

a first transmission clutch that is capable of switching on and off a first power transmission between the first motor generator and the transmission;

a second transmission clutch that is capable of switching on and off a second power transmission between the transmission and the driving wheel;

a second motor generator that is capable of outputting a torque to be transmitted to the driving wheel in a state in which the first transmission clutch is disengaged; and

an oil pump that is coupled to a motor shaft of the first motor generator and that is driven by rotation of the motor shaft.

2. The hybrid vehicle system according to claim 1 , comprising an engine clutch that is capable of switching on and off a third power transmission between the engine and the first motor generator.

3. The hybrid vehicle system according to claim 2 , wherein the engine clutch is provided in the first motor generator.

4. The hybrid vehicle system according to claim 2 , wherein the second motor generator is coupled to an input side of the transmission.

5. The hybrid vehicle system according to claim 2 , wherein the second motor generator is coupled to an output side of the transmission.

6. The hybrid vehicle system according to claim 5 , comprising an output side transmission clutch that is capable of switching on and off a fourth power transmission, between the transmission and the second motor generator.

7. The hybrid vehicle system according to claim 2 , comprising a second oil pump that is coupled to a crankshaft of the engine and that is driven by an output torque from the engine, while the oil pump is a first oil pump.

8. The hybrid vehicle system according to claim 2 , comprising a control device that controls the hybrid vehicle system, wherein the control device is capable of executing

a hybrid traveling mode in which the driving wheel is driven by the torque output from the engine and one or both of the torque output from the first motor generator and the torque output from the second motor generator, and

a motor traveling mode in which the driving wheel is driven by one or both of the torque output from at the first motor generator and the torque output from the second motor generator.

9. The hybrid vehicle system according to claim 8 ,

wherein the control device disengages the first transmission clutch and drives the oil pump by an output torque from the first motor generator while executing a single motor electric vehicle traveling mode in which the driving wheel is driven by only the torque output from the second motor generator.

10. The hybrid vehicle system according to claim 8 , wherein, when starting the engine, the control device cranks the engine by using an output torque from the first motor generator in the state in which the first transmission clutch is disengaged, and starts the engine.

11. The hybrid vehicle system according to claim 8 ,

wherein the control device disengages the engine clutch that is capable of switching on and off the third power transmission between the engine and the first motor generator, while executing a twin motor electric vehicle traveling mode in which the driving wheel is driven by the torque output from the first motor generator and the torque output from the second motor generator.

12. The hybrid vehicle system according to claim 1 , wherein the second motor generator is coupled to an input side of the transmission.

13. The hybrid vehicle system according to claim 1 , wherein the second motor generator is coupled to an output side of the transmission.

14. The hybrid vehicle system according to claim 13 , comprising an output side transmission clutch that is capable of switching on and off a fourth power transmission, between the transmission and the second motor generator.

15. The hybrid vehicle system according to claim 1 , comprising a second oil pump that is coupled to a crankshaft of the engine and that is driven by an output torque from the engine, while the oil pump is a first oil pump.

16. The hybrid vehicle system according to claim 1 , comprising a control device that controls the hybrid vehicle system, wherein the control device is capable of executing

a hybrid traveling mode in which the driving wheel is driven by the torque output from the engine and one or both of the torque output from the first motor generator and the torque output from the second motor generator, and

a motor traveling mode in which the driving wheel is driven by one or both of the torque output from at the first motor generator and the torque output from the second motor generator.

17. The hybrid vehicle system according to claim 16 ,

wherein the control device disengages the first transmission clutch and drives the oil pump by an output torque from the first motor generator while executing a single motor electric vehicle traveling mode in which the driving wheel is driven by only the torque output from the second motor generator.

18. The hybrid vehicle system according to claim 16 , wherein, when starting the engine, the control device cranks the engine by using an output torque from the first motor generator in the state in which the first transmission clutch is disengaged, and starts the engine.

19. The hybrid vehicle system according to claim 16 ,

wherein the control device disengages an engine clutch that is capable of switching on and off a third power transmission between the engine and the first motor generator, while executing a twin motor electric vehicle traveling mode in which the driving wheel is driven by the torque output from the first motor generator and the torque output from the second motor generator.