Vehicle

Abstract

A vehicle includes a first power transmission path, a second power transmission path, and a first clutch provided in the first transmission path to select a connection state between a first connecting state and a first disconnecting state. A second clutch is provided in the second power transmission path to select a connection state between a second connecting state and a second disconnecting state. Circuitry is configured to control the first clutch and the second clutch such that the second clutch switches to the second disconnecting state when a vehicle speed of the vehicle is larger than a first vehicle speed threshold value in a case where the first clutch switches to the first connecting state so as to transmit the power from an internal combustion engine to a wheel and where the second clutch switches to the second connecting state.

What is claimed is: 
     
         1 . A vehicle comprising:
 an internal combustion engine;   a first transmission path configured to transmit power produced by the internal combustion engine to a wheel;   a first switching device arranged on the first transmission path, and configured to be switched between a connecting state which connects the internal combustion engine and the wheel and a disconnecting state which disconnects the internal combustion engine and the wheel;   a first rotating electrical machine;   a second transmission path connecting a junction and the first rotating electrical machine, the junction being located on the first transmission path and closer to the wheel than the first switching device;   a second switching device arranged on the second transmission path, and configured to be switched between a connecting state which connects the first transmission path and the first rotating electrical machine and a disconnecting state which disconnects the first transmission path and the first rotating electrical machine; and   a control circuit configured to control the first switching device and the second switching device, wherein   while the power is being transmitted from the internal combustion engine to the wheel with the first switching device in the connecting state and while the second switching device is in the connecting state, if a vehicle speed of the vehicle becomes greater than a first vehicle speed threshold value, the control circuit switches the second switching device to the disconnecting state.   
     
     
         2 . The vehicle according to  claim 1 , wherein
 while the power is being transmitted from the internal combustion engine to the wheel with the first switching device in the connecting state, if the vehicle speed becomes greater than the first vehicle speed threshold value and the vehicle enters into a cruising state, the control circuit switches the second switching device from the connecting state to the disconnecting state.   
     
     
         3 . The vehicle according to  claim 1 , further comprising:
 a second rotating electrical machine;   a third transmission path connecting an additional junction and the second rotating electrical machine, the additional junction being located on the first transmission path and closer to the internal combustion engine than the first switching device; and   a third switching device arranged on the third transmission path, and configured to be switched between a connecting state which connects the first transmission path and the second rotating electrical machine and a disconnecting state which disconnects the first transmission path and the second rotating electrical machine, wherein   while the power is being transmitted from the internal combustion engine to the wheel with the first switching device in the connecting state, if the vehicle speed becomes greater than the first vehicle speed threshold value, the control circuit performs control to switch the third switching device to the disconnecting state in addition to switching the second switching device to the disconnecting state.   
     
     
         4 . The vehicle according to  claim 3 , further comprising
 a torque limiter arranged on the second transmission path, and configured to limit transmission of the power from the internal combustion engine to the second rotating electrical machine.   
     
     
         5 . The vehicle according to  claim 3 , wherein
 when the first switching device is in the connecting state, the vehicle speed is greater than the first vehicle speed threshold value, and the third switching device is in the disconnecting state, the control circuit performs electric power generation preferential control to switch the first switching device from the connecting state to the disconnecting state, and the third switching device from the disconnecting state to the connecting state, to make the second rotating electrical machine generate electric power using the power from the internal combustion engine, and thereby to supply the electric power to at least one of an energy storage and an electrically-operated accessory of the vehicle.   
     
     
         6 . The vehicle according to  claim 5 , wherein
 when the first switching device is in the connecting state, the vehicle speed is greater than the first vehicle speed threshold value, and the third switching device is in the disconnecting state, if a state of charge in the energy storage becomes less than a predetermined state-of-charge threshold value, the control circuit switches the first switching device from the connecting state to the disconnecting state, and the third switching device from the disconnecting state to the connecting state, to make the second rotating electrical machine generate electric power using the power from the internal combustion engine, and thereby to charge the energy storage.   
     
     
         7 . The vehicle according to  claim 5 , wherein
 while the control circuit is performing the electric power generation preferential control, if the vehicle speed becomes less than a second vehicle speed threshold value, or if an absolute value of a time derivative value of the vehicle speed becomes greater than an acceleration threshold value, the control circuit switches the first switching device from the disconnecting state to the connecting state, and the third switching device from the connecting state to the disconnecting state.   
     
     
         8 . A vehicle comprising:
 an internal combustion engine;   a wheel;   a first transmission path via which power produced by the internal combustion engine is to be transmitted to the wheel;   a first clutch provided in the first transmission path to select a connection state between a first connecting state in which the internal combustion engine and the wheel are connected and a first disconnecting state in which the internal combustion engine and the wheel are disconnected, the first transmission path having a junction provided between the first clutch and the wheel;   a first rotating electrical machine;   a second transmission path to connect the junction to the first rotating electrical machine;   a second clutch provided in the second transmission path to select a connection state between a second connecting state in which the first transmission path and the first rotating electrical machine are connected via the second transmission path and a second disconnecting state in which the first transmission path and the first rotating electrical machine are disconnected; and   circuitry configured to control the first clutch and the second clutch such that the second clutch switches to the second disconnecting state when a vehicle speed of the vehicle is larger than a first vehicle speed threshold value in a case where the first clutch switches to the first connecting state so as to transmit the power from the internal combustion engine to the wheel and where the second clutch switches to the second connecting state.   
     
     
         9 . The vehicle according to  claim 8 , wherein
 while the power is being transmitted from the internal combustion engine to the wheel with the first clutch in the first connecting state, if the vehicle speed becomes greater than the first vehicle speed threshold value and the vehicle enters into a cruising state, the circuitry switches the second clutch from the second connecting state to the second disconnecting state.   
     
     
         10 . The vehicle according to  claim 8 , further comprising:
 a second rotating electrical machine;   a third transmission path connecting an additional junction and the second rotating electrical machine, the additional junction being located on the first transmission path between the wheel and the first clutch; and   a third clutch arranged on the third transmission path, and configured to be switched between a third connecting state which connects the first transmission path and the second rotating electrical machine and a third disconnecting state which disconnects the first transmission path and the second rotating electrical machine, wherein   while the power is being transmitted from the internal combustion engine to the wheel with the first clutch in the first connecting state, if the vehicle speed becomes greater than the first vehicle speed threshold value, the circuitry performs control to switch the third clutch to the third disconnecting state in addition to switching the second clutch to the second disconnecting state.   
     
     
         11 . The vehicle according to  claim 10 , further comprising
 a torque limiter arranged on the second transmission path, and configured to limit transmission of the power from the internal combustion engine to the second rotating electrical machine.   
     
     
         12 . The vehicle according to  claim 10 , wherein
 when the first clutch is in the first connecting state, the vehicle speed is greater than the first vehicle speed threshold value, and the third clutch is in the third disconnecting state, the circuitry performs electric power generation preferential control to switch the first clutch from the first connecting state to the first disconnecting state, and the third clutch from the third disconnecting state to the third connecting state, to make the second rotating electrical machine generate electric power using the power from the internal combustion engine, and thereby to supply the electric power to at least one of an energy storage and an electrically-operated accessory of the vehicle.   
     
     
         13 . The vehicle according to  claim 12 , wherein
 when the first clutch is in the first connecting state, the vehicle speed is greater than the first vehicle speed threshold value, and the third clutch is in the third disconnecting state, if a state of charge in the energy storage becomes less than a predetermined state-of-charge threshold value, the circuitry switches the first clutch from the first connecting state to the first disconnecting state, and the third clutch from the third disconnecting state to the third connecting state, to make the second rotating electrical machine generate electric power using the power from the internal combustion engine, and thereby to charge the energy storage.   
     
     
         14 . The vehicle according to  claim 12 , wherein
 while the circuitry is performing the electric power generation preferential control, if the vehicle speed becomes less than a second vehicle speed threshold value, or if an absolute value of a time derivative value of the vehicle speed becomes greater than an acceleration threshold value, the circuitry switches the first clutch from the first disconnecting state to the first connecting state, and the third clutch from the third connecting state to the third disconnecting state.