A method for controlling an engine clutch includes steps of controlling the hydraulic pressure transmitted from a master cylinder, driven by a motor, to a concentric slave cylinder using a controller outputting a motor control command for controlling an engine clutch so as to switch the engine clutch to a target state, driving the engine clutch using the concentric slave cylinder, after the step of controlling hydraulic pressure, detecting a position of a piston of the master cylinder using a first travel sensor and detecting a position of a piston of the concentric slave cylinder using a second travel sensor, and performing compensation control with respect to the motor based on the positions of the pistons detected by the first travel sensor and the second travel sensor using the controller so that the engine clutch is switched to the target state.

A hydraulic control system of double piston clutch device configured for an automatic transmission, which includes clutch drum connected to one rotation element, a clutch configured in the clutch drum and configured to transmit rotation power in connection with another rotation element through a clutch hub, and a double piston in which first and second pistons are disposed in series to operate the clutch by hydraulic pressure while a front end is disposed to correspond to the clutch, may include a first hydraulic chamber formed between the first piston and the clutch drum to receive the hydraulic pressure through a first passage hole in a sealed state; and a second hydraulic chamber formed between the first and second pistons to receive the hydraulic pressure through a second passage hole in the sealed state and the hydraulic pressure separately controlled is supplied to the first and second hydraulic chambers, respectively.

A clutching device of an automatic transmission may include a clutch drum connected to a first rotation element, a clutch connected to the clutch drum and a second rotation element, and a piston device to operate the clutch, wherein the piston device may include a first piston forming a first sealed space with the first rotation element and the clutch drum and moving toward the clutch by a hydraulic pressure supplied to the first sealed space, a second piston forming a second sealed space with the first piston and moving toward the clutch to directly press the clutch by a hydraulic pressure supplied to the second sealed space, a spring retainer disposed on the first rotation element and forming a third space with the second piston and the first rotation element, and a return spring stored in the third space and abutted by the spring retainer and the second piston.

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.

A clutch connecting/disconnecting device comprises: a clutch pedal; a clutch cylinder; a depression force transmission mechanism; and an actuator. The depression force transmission mechanism is configured to include a cylinder device. The cylinder device includes an input piston, an output piston, a first oil chamber, and a second oil chamber. A pressure receiving area on the first oil chamber side of the output piston is male equal. to a pressure receiving area on the second oil chamber side of the output piston. The first oil chamber and the second oil chamber are connected via an electromagnetic valve connecting and disconnecting between the first oil chamber and the second oil chamber, and the actuator is connected to the output piston in a power transmitting manner.

An electric booster may include: a motor part configured to be driven by power applied thereto; a body part mounted and fixed onto the motor part; a cylinder part coupled to the body part; a screw part connected to the motor part and rotated; a nut part embedded in the body part, and screwed to the screw part so as to linearly move; a first piston part constraining an end of the screw part, and moved to the cylinder part while being pressed by the nut part; a first elastic part supporting the first piston part; a second piston part supported by the first elastic part; and a second elastic part supporting the second piston part.

A starting element with a friction clutch and a piston configured to actuate the friction clutch. The starting element includes a piston space separated from a residual space of the starting element at least partially by the piston, a first connection constructed such that the piston is acted upon by a hydraulic medium proceeding from one side of the residual space, and a second connection fluidically connected to the piston space. A maximum pressure present at the second connection is equal to and/or less than a pressure present at the first connection.

A dog clutch arrangement for a motor vehicle having a clutch body. The clutch body has first teeth in a first toothing and an axially movable sliding sleeve arrangement with second teeth in a second toothing. The sliding sleeve arrangement has a shift ring and a sleeve with the second toothing, and the shift ring and the sleeve are decoupled over a predetermined path by a decoupling element

A method for controlling a hydraulic unit with a rotational-speed-controlled pump which, at an outlet side, provides at least two fluid flows in a manner switched by means of switching valves actuating at least one slave cylinder and for providing a volume flow which is controlled based on a rotational speed of the pump. To set the volume flow, an efficiency of the pump is calculated base on a comparison of a known slave cylinder volume of the at least one slave cylinder and a quantity of fluid of the pump for the filling of the at least one slave cylinder.