Abstract: A dual clutch transmission which has a first clutch, actuated by a first hydraulic cylinder, a second clutch, actuated by a second hydraulic cylinder, shift devices for shifting gears, which are actuated by respective hydraulically operated cylinders, a hydraulic energy source for supplying the hydraulic cylinders and the hydraulically operated cylinders with hydraulic energy and a third clutch that is actuated by a third hydraulic cylinder.

Abstract: A dual clutch transmission which has a first clutch, actuated by a first hydraulic cylinder, a second clutch, actuated by a second hydraulic cylinder, shift devices for shifting gears, which are actuated by respective hydraulically operated cylinders, and a hydraulic energy source for supplying the hydraulic cylinders and the hydraulically operated cylinders with hydraulic energy. The hydraulic energy source has a first pump, a second pump and an electric drive driving the second pump.

Abstract: A double clutch gearbox which has a first volume flow valve for actuating a first clutch, which is arranged downstream, a second volume flow valve for actuating a second clutch which is arranged downstream, and a first hydraulic power source for supplying the volume flow valves and the clutches with a system pressure. In order to provide an improved double clutch gearbox, the clutches have a fluid cooling means which is arranged downstream of the first volume flow valve.

Abstract: A clutch control device for controlling the operation of a hydraulically operated clutch with a flow control valve. The control device includes a volume flow regulating valve that enables both volume flow regulated filling and volume flow regulated emptying of a hydraulic clutch positioning element, to provide rapid and precise operation of the clutch.

Abstract: Valve with a rotary slide. The rotary slide comprises a conduction chamber, which is connected to a first infeed and can optionally be connected to one of a plurality of outlets by changing the rotational position. The rotary slide is designed so that the when pressure is applied the area ratios ensure that a partial pressure equalization always takes place.

Abstract: A pressure medium supply unit for a hydraulic system of a motor vehicle that includes a clutch requiring a high hydraulic pressure and a low volumetric flow rate of hydraulic fluid for operation, and an automatic transmission requiring a low hydraulic pressure and a high volumetric flow rate of hydraulic fluid for operation. A single hydraulic pump is provided to supply hydraulic fluid to both the clutch and the transmission.

Abstract: A double-clutch transmission having at least three and preferably four, hydraulic shift cylinders, and a control device to actuate the hydraulic shift cylinders. To improve the speed of operation when selecting a gear, the shift cylinders needed for gear shifting are actuated with the aid of at least three electromagnetically shiftable directional valves.

Abstract: A dual clutch transmission comprising a first clutch (16), which is hydraulically actuated by a first hydraulic cylinder (19), and a second clutch (18), which is hydraulically actuated by a second hydraulic cylinder (20), in addition to a plurality of hydraulically actuated shift cylinders (11, 12, 13, 14) for shifting gears, which can be subjected to pressure (p1, p2) by means of a selector valve arrangement (51), wherein the first hydraulic cylinder (19) and the second hydraulic cylinder (20) and the selector valve arrangement (51) are connected to a pressure side of a pressure device (24, 25, 26, 27, 28) by means of safety valves (52, 53, 54), which are actuated in unison.

Abstract: A hydraulic pressure reservoir having at least one pressure chamber formed between two opposed, movable inner boundary members. Each inner boundary members includes a spring cover and a diaphragm spring. An outer boundary member peripherally surrounds the movable inner boundary members and has a U-shaped cross section along at least a part of its periphery to axially support the diaphragm springs in a fixed axial position. The outer boundary member can be formed in several pieces that are held together by interconnections or by a surrounding outer tensioning member.

Abstract: A valve having a housing and including a rotatable rotary spool that includes a conducting chamber. A first inlet communicates with the conducting chamber and with a plurality of outlets that are selectively individually connected with the conducting chamber as a function of the rotational position of the rotary spool within the valve housing. The conducting chamber communicates with a first pressure chamber through a first check valve carried by the rotary spool. A second check valve carried by the rotary spool provides communication between the first pressure chamber and a second pressure chamber that surrounds the rotary spool.

Abstract: A hydraulic system comprising a pump for feeding hydraulic fluid from an inlet side to an outlet side, wherein a pressure accumulator is disposed at the outlet side, wherein between the pump and the pressure accumulator a hydraulic control valve is disposed, which has at least two valve positions, wherein the outlet side of the pump is connected to the pressure accumulator in a first valve position, and separated from the pressure accumulator in a second valve position, wherein the outlet side of the pump is connected to the inlet side through the control valve in the second valve position.

Abstract: A device for actuating a plurality of hydraulic control cylinders having a pressure regulating valve with a first and a second pressure regulating output, a first selector valve connected downline from the pressure regulating outputs, a second selector valve connected downline from the first selector valve, having a plurality of individual pressure outputs, where the second pressure regulating output is optionally assignable through the first and second selector valves to one of the individual pressure outputs, and the particular individual pressure outputs that are not assigned to the second pressure regulating output are assignable to the first pressure regulating output.

Abstract: A hydraulic system for supplying a hydraulic fluid to a hydraulically-operated component. A pump for delivering component the hydraulic fluid from a reservoir is connected with the reservoir through a flow control valve. The control valve is a 4/3 directional flow control valve, in which two valve outlet connections are connected to a suction side of the pump and two valve inlet connections are connected to the reservoir. A flow restriction is positioned in each of the conduits extending from the reservoir to the valve inlet connections for reducing the energy consumption of the pump when the need for hydraulic fluid is low.

Abstract: A device for detecting the position of a hydraulic piston-cylinder system, where the hydraulic piston-cylinder system is connected to a position-detecting means which comprises a magnet and a Hall sensor and the connection between the hydraulic piston-cylinder system and the position-detecting means comprises a lever.

Abstract: An hydraulic pressure reservoir having at least one pressure chamber with a fluid connection to a hydraulic circuit. The pressure chamber is formed between a movable partition member carried in a housing and having a pressure limiting valve, and a fixed partition. The movable partition member is in the form of a diaphragm spring.