A dual-clutch actuator with a hydraulic pump, a first and second clutch hydraulic circuits and at least a first shift hydraulic circuit, the shift hydraulic circuit being connected to the hydraulic pump and has a control valve with a return connection. The first clutch hydraulic circuit is connected to the return connection and has a control valve. The second clutch hydraulic circuit is connected to the hydraulic pump and has a control valve. A drive assembly for a vehicle axle of a motor vehicle having an electric motor, a gearbox with an input which is connected to the electric motor, a first and a second gear and an output, a dual clutch arranged between the electric motor and the input of the gearbox, a synchronization assembly arranged between the first gear and the output of the gearbox and an actuator of this kind. The first shift hydraulic circuit is coupled with the synchronization assembly of the first gear.

There is provided a clutch control device which includes an electric oil pump, a clutch unit, and a pressure measurement unit, and which controls an operation of the electric oil pump so as to change a transmission state of the clutch unit. The device includes a pressure control valve that is located between an oil passage for connecting the electric oil pump and the clutch unit to each other and an oil pan for storing an unpressurized hydraulic oil, and that discharges the pressurized hydraulic oil from the oil passage to the oil pan, when pressure of the hydraulic oil exceeds valve opening pressure, and a pump drive control unit that controls hydraulic pressure by driving the electric oil pump, based on target pressure indicated by a change command of the transmission state of the clutch unit and the hydraulic pressure measured by the pressure measurement unit.

A basic pulse time setting section determines a basic pulse time for initial invalid stroke elimination by applying current values of oil temperature and throttle opening to the basic pulse time map. A subtraction time setting section determines a subtraction time by applying current values of oil temperature and clutch oil pressure to the subtraction time map. A pulse time determining section determines a predetermined initial invalid stroke elimination pulse time by subtracting the subtraction time from the basic pulse time. An initial invalid stroke elimination permission/inhibition determination section, at a starting timing of initial invalid stroke elimination, inhibits this-time initial invalid stroke elimination if the elapsed time from the execution timing of the preceding initial invalid stroke elimination is within the predetermined inhibition period.

Disclosed is a hydraulic pressure supply system of a dual clutch transmission for a vehicle in which by independently configuring a low pressure supply route and a high pressure supply route, the hydraulic pressure supply system can enable a low hydraulic pressure that is generated in a hydraulic pump for a low pressure to be supplied to a gear lubrication device and a clutch cooling/lubrication device and enable a low hydraulic pressure that is generated in a hydraulic pump for a high pressure to be supplied to a gear control device and a clutch control device.

A hydraulic system including a hydraulically actuated clutch, a hydraulically actuated shifting piston, and a pressure source for actuating the clutch as well as the shifting piston. The movement of the shifting piston also controls a valve function which serves to open a connection from the pressure source to the clutch only when the shifting piston has reached one of its end positions.

A hydraulic circuit includes a clutch actuator operatively associated with a clutch that may be disposed in a transmission. A hydraulic fluid source supplies pressurized hydraulic fluid for the clutch actuator. To measure the filling rate of the hydraulic actuator, a reference actuator having a predetermined filling rate is disposed in parallel with the hydraulic actuator and in fluid communication with the hydraulic fluid source. If hydraulic pressure associated with the reference actuator does not correspond to the hydraulic pressure associated with the clutch actuator, a compensation valve can appropriately respond by selectively directing hydraulic fluid to or from the clutch actuator. In a further embodiment, the reference actuator and compensation valve may be replaced with an electrohydraulic valve utilizing feedback from the hydraulic pressure present at the inlet of the clutch actuator.

In a control device for a vehicle including: a dog clutch mechanism that is disposed in a power transmission path in which a driving force is transmitted from an engine to a wheel and is operated by a hydraulic actuator; and an electric oil pump that supplies hydraulic pressure to the hydraulic actuator, rotation of the engine is stopped in a state in which the dog clutch mechanism is engaged by the hydraulic pressure supplied from the electric oil pump at a time during an engine stop operation, the rotation of the engine is started in the state in which the dog clutch mechanism is engaged by the hydraulic pressure supplied from the electric oil pump at a time during an engine restart operation, hence occurrence of up-lock of the dog clutch mechanism is prevented.

There is provided a clutch control device which includes an electric oil pump, a clutch unit, and a pressure measurement unit, and which controls an operation of the electric oil pump so as to change a transmission state of the clutch unit. The device includes a pressure control valve that is located between an oil passage for connecting the electric oil pump and the clutch unit to each other and an oil pan for storing an unpressurized hydraulic oil, and that discharges the pressurized hydraulic oil from the oil passage to the oil pan, when pressure of the hydraulic oil exceeds valve opening pressure, and a pump drive control unit that controls hydraulic pressure by driving the electric oil pump, based on target pressure indicated by a change command of the transmission state of the clutch unit and the hydraulic pressure measured by the pressure measurement unit.

An electronically operated autonomous manual transmission clutch system and a second electronically operated vehicle system, such as a belted alternator starter system (BAS), in which the ECU and micro controller of the second electronic system are utilized for both systems.

A basic pulse time setting section determines a basic pulse time for initial invalid stroke elimination by applying current values of oil temperature and throttle opening to the basic pulse time map. A subtraction time setting section determines a subtraction time by applying current values of oil temperature and clutch oil pressure to the subtraction time map. A pulse time determining section determines a predetermined initial invalid stroke elimination pulse time by subtracting the subtraction time from the basic pulse time. An initial invalid stroke elimination permission/inhibition determination section, at a starting timing of initial invalid stroke elimination, inhibits this-time initial invalid stroke elimination if the elapsed time from the execution timing of the preceding initial invalid stroke elimination is within the predetermined inhibition period.