Abstract: In a hydraulic clutch actuation system for controlling in particular a clutch-controlled compensation unit of a drivetrain of a motor vehicle, in which hydraulic clutch actuation system a hydraulic pump is used for generating hydraulic pressure in a hydraulic fluid for the purposes of clutch actuation by means of a hydraulic clutch actuation device, provision is made whereby the hydraulic fluid is supplied as clutch oil to the friction members of the friction clutch which are to be oiled with clutch oil (cooling and/or lubricating oil). In this way, improved and more reliable oiling of the clutch can be made possible even at low vehicle speeds and under heavy clutch load, wherein, despite this, very rapid dry-running of the cutches, and low power losses generated by the clutch oiling, are ensured.

Abstract: For the operation of a gearless clutch-controlled differential unit with a first clutch and a second clutch, without abandoning the possibility of assigning different torques to the clutches, it is provided that a control variable originally generated by a control variable unit is supplied to the first clutch unchanged while the control variable is supplied to the second clutch subject to the intermediate connection of an individual control element. The first and second clutches have clutch characteristics that are distinct from one another.

Abstract: In order to provide a hydraulic actuating system for actuating a parking lock of a motor vehicle, which hydraulic actuating system manages with as few components as possible which are simple, robust, relatively insusceptible to faults and inexpensive, with a simultaneously low installation space requirement, and the hydraulic layout of which hydraulic actuating system makes a simple actuation and a simple movement possible for locking and unlocking the parking lock, it is provided that a pumping device which can operate bidirectionally with a locking delivery direction and with a releasing delivery direction is used as pumping device, and check valves are arranged in the hydraulic circuit in such a way that, by way of actuation of the pumping device in the locking delivery direction, the parking lock moves into the locked position and, upon actuation of the pumping device in the releasing delivery direction, the parking lock moves into the released position.

Abstract: In a hydraulic clutch actuation system for controlling in particular a clutch-controlled compensation unit of a drivetrain of a motor vehicle, in which hydraulic clutch actuation system a hydraulic pump is used for generating hydraulic pressure in a hydraulic fluid for the purposes of clutch actuation by means of a hydraulic clutch actuation device, provision is made whereby the hydraulic fluid is supplied as clutch oil to the friction members of the friction clutch which are to be oiled with clutch oil (cooling and/or lubricating oil). In this way, improved and more reliable oiling of the clutch can be made possible even at low vehicle speeds and under heavy clutch load, wherein, despite this, very rapid dry-running of the cutches, and low power losses generated by the clutch oiling, are ensured.

Abstract: In a drive train for a motor vehicle, which has a permanently driven primary drive train and a secondary drive train which can be connected to the primary drive train when necessary or decoupled therefrom, in order to couple or decouple from the primary drive train, there is provision for actuating a clutch apparatus of a device for power transmission and/or power distribution, in which the disengagement unit when providing the clutch actuation force which is required for the actuation of the clutch apparatus is operationally connected to secondary drive members or in which there is provided a drive clutch which, in order to provide the clutch actuation force required for the actuation of the clutch apparatus, is capable of producing an operational connection between the primary drive members or the secondary drive members and a manipulated variable unit of the disengagement unit.

Abstract: In order to provide a hydraulic actuating system for actuating a parking lock of a motor vehicle, which hydraulic actuating system manages with as few components as possible which are simple, robust, relatively insusceptible to faults and inexpensive, with a simultaneously low installation space requirement, and the hydraulic layout of which hydraulic actuating system makes a simple actuation and a simple movement possible for locking and unlocking the parking lock, it is provided that a pumping device which can operate bidirectionally with a locking delivery direction and with a releasing delivery direction is used as pumping device, and check valves are arranged in the hydraulic circuit in such a way that, by way of actuation of the pumping device in the locking delivery direction, the parking lock moves into the locked position and, upon actuation of the pumping device in the releasing delivery direction, the parking lock moves into the released position.

Abstract: For the operation of a gearless clutch-controlled differential unit with a first clutch and a second clutch, without abandoning the possibility of assigning different torques to the clutches, it is provided that a control variable originally generated by a control variable unit is supplied to the first clutch unchanged while the control variable is supplied to the second clutch subject to the intermediate connection of an individual control element. The first and second clutches have clutch characteristics that are distinct from one another.

Abstract: An automated transmission comprises a hydraulic control device and one or more hydraulically actuated gear units. The hydraulic control device comprises a control unit for setting actuating pressures on the gear units; a base pressure control valve for adjusting a hydraulic base pressure of the hydraulic control device; and a device for controlling the base pressure control valve dependent on the actuating pressures. The automated transmission further comprises a device for switching through an actuating hydraulic pressure to the base pressure control valve. A method comprises the method steps of adjusting a hydraulic base pressure at the hydraulic control device; adjusting actuating pressures for actuating one or more transmission units; switching through one of the actuating pressures to the base pressure control valve; and adjusting the hydraulic base pressure by one of the actuating pressures.

Abstract: A method of feeding a clutch cylinder in a hydraulically actuated clutch system in a motor vehicle and a respective hydraulically actuated clutch system are suggested. The clutch system comprises at least one clutch that can be closed by filling the clutch cylinder; and a hydraulic system that provides a system pressure and has a clutch control valve having an inlet and an outlet. A system pressure is applied at the inlet of the control valve; the clutch pressure for actuating the clutch is provided at the outlet; and the system pressure is decreased pressure prior to and during the filling of the clutch cylinder. The decreased system pressure allows a high volume flow and therefore a fast filling of the clutch cylinder without establishing a premature torque transmitting capacity in the clutch.

Abstract: An automated transmission comprises a hydraulic control device and one or more hydraulically actuated gear units. The hydraulic control device comprises a control unit for setting actuating pressures on the gear units; a base pressure control valve for adjusting a hydraulic base pressure of the hydraulic control device; and a device for controlling the base pressure control valve dependent on the actuating pressures. The automated transmission further comprises a device for switching through an actuating hydraulic pressure to the base pressure control valve. A method comprises the method steps of adjusting a hydraulic base pressure at the hydraulic control device; adjusting actuating pressures for actuating one or more transmission units; switching through one of the actuating pressures to the base pressure control valve; and adjusting the hydraulic base pressure by one of the actuating pressures.

Abstract: A hydraulic control apparatus for an automatic dual clutch transmission, comprising a first clutch with a first partial transmission and a second clutch with a second partial transmission, as well as a shifting system for engaging/disengaging gears of the two partial transmissions, a control unit having a first pressure regulator and a second pressure regulator actuating the first and second clutches and actuating the shifting system, and a switching apparatus. The shifting apparatus comprises a first changeover valve and a second changeover valve. Both changeover valves can be shifted from a first to a second position for allowing a safe emergency running mode of a motor vehicle in case of any failure of the first or second pressure regulator.

Abstract: The invention relates to a hydraulic control device for an automatic dual-clutch transmission which has a first clutch and a second clutch, having a control valve unit which predefines at least one hydraulic parameter such as pressure and/or one volume flow. Regulating this parameter engages or disengage the clutches. An additional separating valve can is provided assuming a normal position when the second control signal is applied, so that at least one of the clutches can be operated by means of the control valve unit. The purpose is to provide enhanced operational safety against misoperation while at the same time secure availability of the clutches.

Abstract: The invention relates to a hydraulic control device for an automatic dual-clutch transmission which has a first clutch and a second clutch, having a control valve unit which predefines at least one hydraulic parameter such as pressure and/or one volume flow. Regulating this parameter engages or disengage the clutches. An additional separating valve can is provided, and by means of a first switching valve to be operated by means of at least one further control signal the first clutch can be regardless of the switching position of the separating valve. The purpose is to provide enhanced operational safety against misoperation while at the same time secure availability of the clutches.

Abstract: A method of feeding a clutch cylinder in a hydraulically actuated clutch system in a motor vehicle and a respective hydraulically actuated clutch system are suggested. The clutch system comprises at least one clutch that can be closed by filling the clutch cylinder; and a hydraulic system that provides a system pressure and has a clutch control valve having an inlet and an outlet. A system pressure is applied at the inlet of the control valve; the clutch pressure for actuating the clutch is provided at the outlet; and the system pressure is decreased pressure prior to and during the filling of the clutch cylinder. The decreased system pressure allows a high volume flow and therefore a fast filling of the clutch cylinder without establishing a premature torque transmitting capacity in the clutch.

Abstract: The invention relates to a switching-valve arrangement for a shifting system of an automatic transmission having a first actuator for engaging and releasing gears, at least a second actuator for engaging and releasing gears, a first activatable switching valve, a second activatable switching valve, a first signal element, and a second signal element. By means of the signal elements and switching valves the first and second actuators can be pressurized. In case of failure of one of the signal elements one of the actuators can always be pressurized and even in case of erroneous operation of the first and second signal elements only one of the actuators can be pressurized at the same time.

Abstract: A hydraulic control apparatus for an automatic dual clutch transmission, comprising a first clutch with a first partial transmission and a second clutch with a second partial transmission, as well as a shifting system for engaging/disengaging gears of the two partial transmissions, a control unit having a first pressure regulator and a second pressure regulator actuating the first and second clutches and actuating the shifting system, and a switching apparatus. The shifting apparatus comprises a first changeover valve and a second changeover valve. Both changeover valves can be shifted from a first to a second position for allowing a safe emergency running mode of a motor vehicle in case of any failure of the first or second pressure regulator.

Abstract: A hydraulic system for providing pressure and volume flows in a double-clutch transmission. A first clutch and a second clutch are preceded by at least one changeover valve which, in a first state, guides lubricating flow to the first clutch and cooling flow to the second clutch, and, in a second state, guides lubricating flow to the second clutch and cooling flow to the first clutch. The cooling flow is preferably variable.

Abstract: The invention relates to a hydraulic system (1) for providing pressures and volumetric flows in a dual clutch transmission, in particular for providing a first volumetric flow for cooling and lubricating a first clutch (2) and for providing a second volumetric flow for cooling and lubricating a second clutch (3). The hydraulic system is distinguished by the fact that at least one switching valve (4), which in a first position guides a lubricating flow onto the first clutch (2) and a cooling flow onto the second clutch (3) and in a second position guides the lubricating flow onto the second clutch (3) and the cooling flow onto the first clutch (2), is connected upstream of the first clutch (2) and the second clutch (3). The cooling flow is preferably variable.

Abstract: The invention relates to a hydraulic control apparatus (1) for a shifting fork (7) for engaging/releasing at least one gear (G) in a manual transmission, comprising at least one shifting cylinder (2, 3) and a piston unit (6) which can move within the shifting cylinder and is connected to the shifting fork (7), and at least one control valve (8) for generating a modeled pressure which can be applied to the piston unit (6) in order to actuate the shifting fork (7). To prevent jolting when the piston unit is started up, the invention proposes a valve apparatus which provides a counter-pressure which counteracts the movement of the piston unit (6). In a preferred exemplary embodiment, a diaphragm ensures that the counter-pressure drops below the value preset by the valve apparatus at low speeds on the part of the piston unit.

Abstract: The invention relates to a hydraulic control device for an automatic dual-clutch transmission which has a first clutch and a second clutch, having a control valve unit which predefines at least one hydraulic parameter such as pressure and/or one volume flow. Regulating this parameter engages or disengage the clutches. An additional separating valve can is provided, and by means of a first switching valve to be operated by means of at least one further control signal the first clutch can be regardless of the switching position of the separating valve. The purpose is to provide enhanced operational safety against misoperation while at the same time secure availability of the clutches.