Getrag Ford Transmissions Gmbh

Reinhard Moehlmann

Martin Leibbrandt

Andreas Hegerath

Ulrich Eggert

Christian Krauss

Marco Siebigteroth

Georg Hillebrand

Stefan Kirschstein

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.

Automated transmission and method for operating an automated transmission

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.

Method of feeding a clutch cylinder of a hydraulically actuated clutch system

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.

Hydraulic control apparatus for an automatic dual clutch transmission

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.

Hydraulic control apparatus for an automatic dual-clutch transmission

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.

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.

Switching-valve arrangement for a shifting system of an automatic transmission

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.

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Kö'ln, Germany

Reinhard Moehlmann