Volkswagen Ag

Temic Telefunken Microelectronic Gmbh

Norbert Ramm

Gerhard Hettich

Michael Genzel

Frank Zimmermann

Georg Kruse

An arrangement for the controlled engagement and disengagement of a clutch in the transmission of a motor vehicle drive system includes an engine and an automatic transmission which can be activated electro-hydraulically. In order to avoid 'stationary-state shaking', a preselected value for the clutch slip torque is determined as a function of a prehistory of limited duration in the form of an evaluation of the speed profile of the motor vehicle in the immediate past.

Transmission clutch control arrangement

A device is proposed to determine the rotational speed of a transfer element (3) arranged in variable-diameter pulleys (1, 2) of a continuously variable transmission system, the said device Consisting of a sliding stock (4, 15), with a sensor (10, 16) which is supported on the transfer element (3) on the inner sides of the variable-diameter pulleys, which sliding stock is connected to the transmission case (8) by a spring (6) loaded rocker arm (5) mounted in a swivelling joint (7). With the knowledge of the peripheral speed of the transfer element (3), the rotary speeds (N1, N2) of the set of variable-diameter pulleys (1, 2) and the effective transmission radii (r1, r2), the slippage can be determined between the transfer element (3) and the sets of variable-diameter pulleys (1, 2). By comparing the previously established maximum amounts of slippage with the detected amounts of slippage, the maximum requisite pressure applied by the axially shifting variable-diameter pulley (9) in each set of variable-diameter pulleys (1, 2) can be adjusted to the optimum amount (see FIG. 1).

Device for determining belt rotational speed of continuously variable

A process to adjust the pretensioning force for the transmission element of a continuously variable transmission, complete with two disc assemblies comprising two discs each, will be described. For optimized specification of the pretensioning force, the following process steps will be provided:

Pretensioning force adjustment of continuously variable transmission

A motor vehicle includes a drive system consisting of an engine and an electrohydraulically actuatable automatic transmission connected to the vehicle body by resilient mounts. To reduce stationary vibration of the vehicle and engagement and disengagement shock, the engagement pressure of a clutch in the transmission is controlled so that the clutch begins to slip when the strain between the drive system and the vehicle body reaches a selected value. The strain is determined by detecting the displacement of the drive system with respect to the body or the torque in the drive system or the stress in the resilient mounts.

Method and apparatus for controlling engagement and disengagement of the

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

The specification discloses a method for controlling shifting parameters of an automatic transmission having a planetary gear arrangement including a sun gear, planet gears and a ring gear, where the mechanical linkage of any two of these components represents a mechanical gear ratio. To obtain exact control of shifting, the speed variations of the sun gear are measured and these measured values are used for precise determination of the coupling point or of the duration of shifting and/or for engine management.

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Braunschweig, Germany

Norbert Ramm