Abstract: A hydraulic control device for an automatic transmission includes a shut-off valve arranged between a first pressure adjusting device and a respective shifting element cylinder of a plurality of shifting elements. In the first shifting position of the shut-off valve, the first pressure adjusting device is hydraulically connected to the respective shifting element cylinder through the shut-off valve. In the second shifting position of the shut-off valve, the shifting element cylinder is sealed by the shut-off valve relative to the first pressure adjusting device. The shut-off valve is an releasable check valve. The releasable check valve includes a check valve and an unblocking device. The unblocking device is actuatable by a control pressure from a second pressure adjusting device.

Abstract: A hydraulic control device for an automatic transmission includes a shut-off valve arranged between a first pressure adjusting device and a respective shifting element cylinder of a plurality of shifting elements. In the first shifting position of the shut-off valve, the first pressure adjusting device is hydraulically connected to the respective shifting element cylinder through the shut-off valve. In the second shifting position of the shut-off valve, the shifting element cylinder is sealed by the shut-off valve relative to the first pressure adjusting device. The shut-off valve is an releasable check valve. The releasable check valve includes a check valve and an unblocking device. The unblocking device is actuatable by a control pressure from a second pressure adjusting device.

Abstract: An arrangement for supplying oil to a chain drive which drives a transmission oil pump that is axially offset relative to a torque converter and embedded in an intermediate plate in a vehicle having a torque converter. The driven sprocket of the chain drive is supported by a converter neck mounted in a centering plate. A seal is provided between the converter neck and the sprocket and is arranged adjacent the sliding fit between the converter neck and the sprocket. To compensate for the suppression of lubrication of the seal, the neck bearing and the chain drive, a valve is integrated in the intermediate plate, and a duct is provided in the plane, in which the centering plate is screwed to the intermediate plate, such that excess oil flowing from the valve is selectively directed to the seal, the neck bearing and the chain drive.

Abstract: A transmission for a vehicle with a clutch and/or a brake which is hydraulically actuated by a cylinder and a piston actuator. A pressure chamber is located between the cylinder and the piston and a hydraulic pressure medium flows into the pressure chamber via an inlet. The pressure medium is supplied to the pressure chamber via a component fixed on the housing, a rotary passage between the fixed component and the rotatable component and then via the rotatable component. The radial distance of the radial middle of the rotary passage is larger than the smallest radial distance and smaller than the largest radial distance of the pressure chamber from the rotation axis of a central shaft of the automatic transmission. The radial arrangement of the rotary passage, between the radially smallest and largest diameters of the pressure chamber, neutralizes centrifugally generated forces on the pressure medium in the pressure chamber.

Abstract: A method and device for actuating a shift element of an automatic transmission having a start-stop function and a pressure medium pump driven by an internal combustion engine. The shifting elements are clutches or brakes that can be actuated by a piston which is actuated for engagement via pressure supplied to a pressure space. The pressure space is depressurized when the engine stops. To enhance start-stop operation, the shifting elements comprise an additional pressure space that acts, in opposition to the pressure space acting in the engaging direction, as a controllable restoring mechanism which can be rendered inactive, if desired. If the engine stops and the automatic start-stop function is activated, the additional pressure spaces, acting in the restoring direction, are depressurized before the pressure drop in the pressure spaces, acting in the engaging direction, of the pistons, but are otherwise permanently pressurized during driving operation.

Abstract: A device for controlling a rotating shifting element of an automatic transmission for a start/stop operation. The shifting element is actuated by an axially moving piston which is biased, in a disengaging direction, by a spring and biased, in an engaging direction, by hydraulic pressure supplied to a pressure space. At least one spring-loaded latch, which able to move in the radial direction, is arranged in the pressure space. The spring-loaded latch, when the combustion engine is running, rotates with the piston and acts upon the piston such that if the engine stops, the previously engaged shifting element is locked by spring force and, as the pressure decreases, the shifting element disengages slightly, at most only slightly, and when the engine is re-started, the locking action is again released by centrifugal force, in opposition to the spring force, so that the piston remains engaged by the hydraulic pressure build-up in the pressure chamber.

Abstract: A drive device (2) for the oil pump (6) of a motor vehicle automatic transmission, in which the oil pump (6) on the one hand can be coupled to the drive motor by way of an overrunning clutch (34) and on the other hand is drivingly connected to an auxiliary electric motor (22), which is powered by the on-board power supply of the motor vehicle. The electric motor (22) is arranged outside of the pump housing (8) and is drivingly connected to a driven pump impeller wheel (ring gear 10) that is arranged in the pump housing via a non-rotatable connection.

Abstract: A transmission for a vehicle with a clutch and/or a brake which is hydraulically actuated by a cylinder and a piston actuator. A pressure chamber is located between the cylinder and the piston and a hydraulic pressure medium flows into the pressure chamber via an inlet. The pressure medium is supplied to the pressure chamber via a component fixed on the housing, a rotary passage between the fixed component and the rotatable component and then via the rotatable component. The radial distance of the radial middle of the rotary passage is larger than the smallest radial distance and smaller than the largest radial distance of the pressure chamber from the rotation axis of a central shaft of the automatic transmission. The radial arrangement of the rotary passage, between the radially smallest and largest diameters of the pressure chamber, neutralizes centrifugally generated forces on the pressure medium in the pressure chamber.