A continuous variable transmission (CVT) hydraulic pressure control device includes: a pressure regulation valve regulating an operation pressure of oil supplied to a friction element of a forward-rearward device; and a switch valve to respectively switch oil discharge paths through which the oil supplied to the friction element is discharged, respectively by a pilot pressure from the pressure regulation valve and an elastic force of a return spring. In particular, the oil discharge paths switched by the switch valve have oil flow resistances different from each other.

A method is for testing a hydraulic system (1), having a pump (2) which, in a first direction of rotation (3), conveys fluid to a first consumer (4) for a volume flow function and, in a second direction of rotation (5), conveys fluid to at least one second consumer (6) for an actuation function. The method includes testing hydraulic readiness of the hydraulic system (1); drawing fluid into the hydraulic system (1); ventilating the hydraulic system (1). A hydraulic system (1) carries out such a method, having a pump (2) which can be driven in a first direction of rotation (3) for a volume flow function and can be driven in a second direction of rotation (5) for an actuation function.

This clutch control device includes an engine (13), a transmission (21), a clutch device (26) configured to connect and disconnect motive power transmission between the engine (13) and the transmission (21), a clutch actuator (50) configured to drive the clutch device (26) and change a clutch capacity, a hydraulic circuit (63) provided between the clutch device (26) and the clutch actuator (50), an air bleeding device (64) configured to perform air bleeding of the hydraulic circuit (63), a control unit (60) configured to calculate a control target value of the clutch capacity, a control mode changeover switch (59) configured to enable a control mode of the control unit (60) to be switched to an air bleeding mode, and an air bleeding switch (65) configured to enable a hydraulic pressure of the hydraulic circuit (63) to increase in the air bleeding mode.

The clutch control device comprises: a pump that feeds oil to a hydraulic clutch; a control part that controls the pump; an input-side oil channel through which oil suctioned into the pump from an oil tank passes; an output-side oil channel connecting the pump and the hydraulic clutch; a pressure sensor; a connecting oil channel connected to the input-side oil channel and the output-side oil channel; and a solenoid valve that interrupts or allows the flow of oil in the connecting oil channel. The opening degree of the valve can be adjusted. When a drive shaft and a driven shaft are connected by the hydraulic clutch, the control part adjusts the opening degree of the valve on the basis of the pressure of oil in the output-side oil channel and the number of rotations made by the driven shaft while monotonically increasing the number of rotations of the drive part.

A clutch control device includes a pump to feed oil to a hydraulic clutch, an input side oil passage connecting an oil tank and the pump and through which oil sucked from the oil tank to the pump passes, and an output side oil passage connecting the pump and the hydraulic clutch and through which oil that is pressurized by the pump and is fed from the pump to the hydraulic clutch passes. A damper connected to the input side oil passage and the output side oil passage includes an oil container containing oil, a partition that partitions the oil container into first and second spaces along a predetermined direction and at least a portion of which is movable in the predetermined direction, a first connection oil passage connecting the first space and the input side oil passage, a second connection oil passage connecting the second space and the output side oil passage, and an elastic portion that applies a force to the partition to move the partition toward the second space in the predetermined direction. The first and second spaces are filled with oil.

The clutch control device comprises: a pump that feeds oil to a hydraulic clutch; a control part that controls the pump; an input-side oil channel through which oil suctioned into the pump from an oil tank passes; an output-side oil channel connecting the pump and the hydraulic clutch; a pressure sensor; a connecting oil channel connected to the input-side oil channel and the output-side oil channel; and a solenoid valve that interrupts or allows the flow of oil in the connecting oil channel. The opening degree of the valve can be adjusted. When a drive shaft and a driven shaft are connected by the hydraulic clutch, the control part adjusts the opening degree of the valve on the basis of the pressure of oil in the output-side oil channel and the number of rotations made by the driven shaft while monotonically increasing the number of rotations of the drive part.

A hydraulic line coupling, for a hydraulic brake or clutch of handlebar-operated vehicles, having a line connection piece with a hydraulic line extension and a housing with a coupling opening, in which the line connection piece for coupling the line to the housing can be disposed. The connection piece comprises a passage connected to the line. A valve device is disposed in the housing and is configured such that the valve device closes the connection for the connection piece when the connection piece is not in the coupling opening. The line coupling has a seal, with which seal the valve device closes the connection for the connection piece when the connection piece is not in the coupling opening. With the seal, the connection piece seals the passage from the environment when the connection piece is in the coupling opening.

A clutch control device includes a pump to feed oil to a hydraulic clutch, an input side oil passage connecting an oil tank and the pump and through which oil sucked from the oil tank to the pump passes, and an output side oil passage connecting the pump and the hydraulic clutch and through which oil that is pressurized by the pump and is fed from the pump to the hydraulic clutch passes. A damper connected to the input side oil passage and the output side oil passage includes an oil container containing oil, a partition that partitions the oil container into first and second spaces along a predetermined direction and at least a portion of which is movable in the predetermined direction, a first connection oil passage connecting the first space and the input side oil passage, a second connection oil passage connecting the second space and the output side oil passage, and an elastic portion that applies a force to the partition to move the partition toward the second space in the predetermined direction. The first and second spaces are filled with oil.

Hydraulic system and method for controlling pressure in a hydraulic system for a vehicle transmission with at least a primary friction element (2) and a secondary friction element (3) for coupling and transmitting engine power to the wheels of the vehicle by actuation of the friction elements (2) via the hydraulic system, comprising; supplying pressurized fluid to a line pressure circuit (7) by means of a pressure pump system having at least two outlet lines (5); providing a bypass circuit (9) on the pressure pump system that, when the bypass circuit (9) is open to allow flow therethrough; providing a bypass operating element (11) for controlling the bypass circuit (9) via a bypass valve (10); wherein the bypass operating element (11) additionally controls the secondary pressure on the secondary friction element (3) via a secondary valve (19); such that in a determined state; the bypass operating element (11) is actuated to open the bypass circuit (9) to reduce the flow to the line pressure circuit (7) and additionally to reduce the pressure on the secondary friction element (3) to a value lower than the pressure on the primary friction element (2), such that less torque is provided.

A clutch actuating device has an actuating cylinder with piston and rod-side chamber, a multiplier cylinder with piston-side and rod-side chambers separated by a piston, a rod(s) interconnecting the pistons, and a directional control valve. The valve has a pilot port, ports in fluid connection with piston-side and rod-side chambers of the multiplier cylinder, and a port in fluid connection with a secondary source. When a first fluid pressure (P1) from a first pressure source is applied to the pilot port and rod-side chamber of the actuating cylinder, a second fluid pressure (P2) is applied to the piston-side chamber of the multiplier cylinder by the secondary source. This results in the first and second fluid pressures (P1 and P2) acting on the piston of the actuating cylinder to produce a clutch actuation fluid pressure.