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 method for the transmission and damping of a mean torque with a superposed alternating torque having an input and an output. The mean and superposed alternating torque is transmitted along a torque path from the input to the output area. An input speed is a mean speed and a superposed alternating component. A slip arrangement is provided in the torque path between the input and the output for transmitting the mean and superposed alternating torque and generating a speed slip between an input speed and an output speed. The slip arrangement provides a maximum of an external activation of the speed slip in a area of the maxima of at least one periodic oscillation component of the alternating component and provides a minimum of an external activation of the speed slip in an area of the minima of at least one periodic oscillation component of the alternating component.

A method for the transmission and damping of a mean torque with a superposed alternating torque in an arrangement having an input and an output. The mean torque and superposed alternating torque are transmitted along a path from the input to the output. A slip arrangement is provided in the torque path between the input and the output for transmitting mean torque and superposed alternating torque and for generating a speed slip between an input speed and an output speed in the path. The slip arrangement provides a maximum of an external activation of the speed slip in the area of the maxima of at least one periodic oscillation component of the alternating component and provides a minimum of an external activation of the speed slip in the area of the minima of at least one periodic oscillation component of the alternating component.

A method for transmission of and damping of a mean torque with a superposed alternating torque in a torque transmission arrangement for a powertrain of a motor vehicle having an input and an output. The mean torque with the superposed alternating torque is transmitted along a torque path from the input the output. The input rotates at an input speed and the output rotates at an output speed. A slip arrangement is provided in the torque path between the input and the output for generating a speed slip. The slip arrangement provides a maximum of an external activation of the speed slip in the area of a maxima of at least one periodic oscillation component of an alternating component and provides a minimum of an external activation of the speed slip in the area of a minima of at least one periodic oscillation component of the alternating component (new).

Methods and systems are provided for operating a vehicle that may be propelled via a primary axle and a secondary axle. In one example, a propulsion source of a secondary axle may be decoupled from at least one wheel via a dog clutch that includes teeth. The dog clutch may be disengaged in a way that reduces driveline noise and may reduce a possibility of driveline degradation.

Disclosed is a regulator for clutch operating mechanism. The regulator includes a main body, a supply flow path for fluid flow from a master cylinder to an operating cylinder, and a return flow for fluid flow from the operating cylinder to the master cylinder inside of the main body. The regulator further includes a first valve installed inside the main body and configured to close an exit of the return flow path and open the supply flow path when the fluid flows to the operating cylinder and a second valve installed inside the main body configured to close an exit of the supply flow path and to open the return flow path when the fluid flows to the master cylinder. The regulator further includes a damping apparatus having a damping space which communicates with the supply flow path of the main body and whose internal capacity changes according to hydraulic pressure.

A regulator for clutch actuator includes a housing having a cylindrical damping space inside, a first fluid path interconnecting the damping space and a master cylinder, and a second fluid path interconnecting the damping space and a an operating cylinder. The regulator further includes a flexible valve member contained in the damping space for reducing vibrations. The flexible valve member comprises a first inflow guiding portion configured to receive and guide fluid from the first fluid path. The first inflow guiding portion has a plurality of through holes such that elastic deformation of the first inflow guiding portion reduces vibration when fluid flow into the cylindrical damping space from the master cylinder.

Controlling a multiplate clutch situated between an input shaft and an output shaft for the switchable transmission of torques, wherein in the event of a torque request and a subsequent engagement of the multiplate clutch, includes: a) determining a setpoint engagement force, acting in an axial direction, of the multiplate clutch for transmitting a setpoint torque to the output shaft; b) determining and setting a limiting engagement force that is less than the setpoint engagement force, and c) setting the setpoint engagement force in a time-delayed manner;

wherein a transmission of an actual torque is achieved by limiting the setpoint engagement force to the limiting engagement force, so that a maximum actual torque that is transmitted upon engagement of the multiplate clutch exceeds a setpoint torque to be transmitted by at most 5%.

A system for controlling a clutch in a heavy vehicle including an internal combustion engine and an automated mechanical transmission, where the engine is running, the clutch is engaged and the transmission is in neutral, including an electronic control unit adapted to receive a request to shut down the engine, to disengage the clutch of the transmission, and to shut down the engine, where the electronic control unit is adapted to reengage the clutch when the rotation of the engine and the rotation of the transmission input shaft is zero, and to actively slow down rotation of the transmission input shaft by the use of a brake device if the stop time for the transmission input shaft exceeds a predefined time interval. The advantage of the invention is that vibrations and noise are reduced during shut down of the engine.

Embodiments of the present invention provide an electric machine control system for a vehicle, the electric machine control system comprising one or more controllers, wherein the vehicle comprises an electric machine arranged to be selectively coupleable to provide torque to at least one wheel of an axle of the vehicle, the control system comprising input means arranged to receive a speed signal (410) indicative of a speed of the vehicle and a status signal (470) indicative of a status of a coupling of the electric machine to the at least one wheel of an axle of the vehicle, output means (340) arranged to output a coupling signal to control coupling of the electric machine to the at least one wheel of the axle, and processing means arranged to determine (1210) a coupling state of the electric machine to the at least one wheel of the axle and to control the output means to output (1220) a coupling signal indicative of the determined coupling state, wherein the processing means is arranged, in dependence on the status signal being indicative of a failure (1230) to change the coupling state of the electric machine to the at least one wheel of the axle in dependence on a change in the determined coupling state, to control the output means to output the coupling signal (345) indicative of a retry (1250) of the change in the coupling state in dependence on the speed signal.