Volkswagen Ag

Georg Kruse

Ekkehard Pott

Roland Meyer

Rainer Hofmann

Norbert Ramm

Wolfgang Schreiber

Ansgar Damm

Marc Hladun

Raimar Warnecke

Shaun E Mepham

Markus Novotny

Hanno Jelden

Kai Bohnstedt

Volker Pichmann

Carsten Adomeit

Gerhard Preine

Volker Becker

Tobias Lösche-Ter Horst

Axel Ibenthal

Wolf-R&uuml;diger Lutz

Ulrich Remmlinger

Herbert Ruholl

Benjamin Kaczor

Lloyd Storey

Marcel Zirwes

Norbert Weiß

Frank Schade

Peter Moeller

Thomas Stremlau

Dirk Nicke

Axel Zergiebel

Peter Merk

Wolf-Rüdiger Lutz

John Lipman

Robert Robinson

Richard G Griffiths

Stuart Holden

Stefanie Jauns-Seyfried

Sven-Oliver Mündemann

An actuation device and a method for actuating a clutch, in particular for a hybrid drive, include a master cylinder having an interior separated by a master piston into master and slave oil chambers. The slave oil chamber is connected, via a valve in a first valve position, to a tank line leading to an oil reservoir and in a second valve position, to a pressure line of the oil reservoir. The master oil chamber is connected via a working line to an oil chamber of a slave cylinder and to a compensating tank via a compensating line as a function of the position of the master piston. The compensating tank has a compensating volume which has, at its highest point, an overflow which is connected to the tank line and in its first position the valve connects the slave oil chamber to the compensating tank via a return line.

Actuation device for a clutch

An internal combustion engine drives, via a belt drive, a first and a second auxiliary unit embodied respectively as a water pump and an air-conditioning compressor and drives a starter-generator operating as a starter and as a generator depending on the operating mode. The belt drive is connected through a clutch element, which has a freewheel, to the internal combustion engine such that, when the internal combustion engine is at standstill, only the two auxiliary units, but not at the same time the internal combustion engine, are driven by the starter-generator. The clutch element which has a freewheel allows a stepless transition of the drive mode from the internal combustion engine to the starter-generator. In order to start the internal combustion engine, the clutch element is engaged only for a short time, so that the drive power of the starter-generator is transmitted to the internal combustion engine.

Drive unit with an internal combustion engine

A method for controlling a drivetrain of a motor vehicle is provided. The drivetrain includes, as components, at least an internal combustion engine, an electric drive machine, a clutch and a transmission that can be connected to drive wheels. A control device initiates gear shifts at the transmission based on a wide variety of sensor signals by using a characteristic diagram. In order to ensure an excellent shift quality over long operating periods, a drive torque value Mof the internal combustion engine, which is determined by the control device, can be checked and if necessary corrected in dependence of given conditions by determining the drive torque value Mof the electric drive machine.

Method for controlling a drivetrain of a motor vehicle

A hydraulic circuit for a motor vehicle transmission, preferably a twin-clutch transmission, is connected for cooling at least one clutch of the transmission. The hydraulic circuit is preferably a low-pressure circuit and it includes at least one hydraulic pump, at least one filter element, for filtering the hydraulic oil, and at least one pressure-regulating valve. The circuit-related control sequence and the power consumption of the hydraulic pump are optimized in that at least one adjusting valve is provided in order to control the volume flow of cooling oil flowing to the clutch, in that a pressure-compensation valve is provided in addition, and in that the pressure-regulating valve, the adjusting valve and/or the pressure-compensation valve are arranged and/or formed within the hydraulic circuit such that the pressure difference between the supply pressure and the establishing cooling-oil pressure is essentially constant.

Hydraulic circuit for a transmission of a motor vehicle

A twin clutch, in particular an actively closing, dry friction twin clutch is provided for a twin clutch transmission of a motor vehicle having an internal combustion engine, a crankshaft, and two transmission input shafts. The two transmission input shafts are connected to respective friction clutches and can be selectively connected to the crankshaft. At least one axial bearing is provided at the twin clutch such that axial forces, which are present when the clutch is actuated, can be transferred to the transmission housing.

Twin clutch

A slide valve for controlling a torque converter bridging clutch for an automatic transmission of a motor vehicle includes a slide housing and a movable control slide by which hydraulic fluid connections and ports may be connected to each other in different ways. The slide includes a first control flange for alternatively or jointly controlling closing and opening lines leading to the converter bridging clutch. To ensure optimal regulation of the converter bridging clutch, the slide has a second control flange for selectively connecting the opening line to a drain port so that the hydraulic fluid can flow continually through the converter bridging clutch to remove heat.

Slide valve for controlling a bridging clutch in an automatic

To improve shifting comfort in an automatic transmission, the transmission output shaft torque is kept as nearly constant as possible during the shifting operation by detecting, prior to and during the entire shift operation, the engine speed, the transmission input shaft speed and torque and the transmission output shaft torque or the torque of the drive wheels, and controlling the engagement and disengagement of transmission elements in accordance with those variables.

Method of regulating and controlling shifting of gears in an automatic

Growing community of inventors

Gifhorn, Germany

Georg Kruse