Volkswagenwerk Aktiengesellschaft

Volkswagen Ag

Frank Zimmermann

Paulus Heidemeyer

Norbert Ramm

Romanus Scholz

Erhard Bigalke

Peter Hofbauer

Hermann Oetting

Hartmut Werner

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 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

A method for operating a vehicle having an automatic, continuously variable speed transmission comprising at least three control phases. During a first control phase, the engine speed is maintained at a substantially constant value while the transmission gear ratio is increased to the maximum transmission gear ratio. During a second control phase, the transmission gear ratio is maintained at the maximum transmission gear ratio while the engine speed is increased to the maximum engine speed possible at the maximum gear ratio and selected throttle valve angle. During a third control phase, the transmission gear ratio is decreased from the maximum transmission gear ratio, so that higher vehicle traveling speeds may be obtained. During the third control phase the transmission gear ratio may be rapidly changed to a ratio corresponding to maximum engine power when the accelerator pedal is placed in a kickdown position. Increased force on the accelerator pedal may be required to place the accelerator pedal in the kickdown position.

Method for operating a vehicle having an automatic, continuously

An arrangement for the automatic actuation of an automobile clutch operatively located between an automobile engine and a manually shiftable transmission, of the kind that includes a servo motor responsive to auxiliary power applied thereto for effecting engagement and disengagement of the clutch, and control means for controlling the auxiliary power delivery to the servo motor as a function of the position of the accelerator pedal, or the clutch input (engine output) and output (transmission input) rotational speeds, or both, and wherein the control means controls the auxiliary power delivery to the servo motor so that the rotational speed of the engine attains a prescribed rotational speed which is a function of the position of the accelerator pedal, the auxiliary power delivery being an application pulse to the servo motor of sufficient duration to almost completely overcome the free travel of the clutch.

Arrangement for automatic clutch actuation

A system for driving a motor vehicle with a infinitely variable belt gear is provided with an engine transversely positioned to the longitudinal direction of the vehicle. First and second drive-cone pulleys are provided for transmitting the rotational force of the engine. A clutch couples the engine with the drive-cone pulleys. A V-belt or chain drivingly connects the first and second output cone pulleys with the first and second drive-cone pulleys. A planetary gear drive with a sun gear, a ring gear, and a planetary gear carrier carrying planet gears is driven by the first and second output cone pulleys. A differential gear for driving the axles of the vehicle is coaxially positioned to the planetary gear with a drive gear coupling the differential gear with the planetary gear.

Engine-gear arrangement for vehicles, in particular passenger cars

Apparatus for automatic actuation of a clutch of an automobile with a manual shift transmission. A pneumatic servo motor controls clutch engagement. A control mechanism, for example a microprocessor, controls the servo motor as a function of accelerator pedal position and/or input and output clutch speeds during starts from stop (initial transmission input speed .perspectiveto.O). The rotation speed of the engine attains a prescribed value preassigned as a function of the accelerator pedal position. For each pedal position, signals to control valves cause the servo motor to vary clutch engagement based on the difference between prescribed and detected engine speeds. The signals can be pulse signals variable in frequency and/or duration by the control mechanism. During starting from stop, for pedal depressions above idle, the rotational speed of the engine remains below maximum tractive power for that pedal position. In a range of pedal positions approaching maximum depression, in one embodiment, the engine speed increases discretely to the maximum tractive power figure at or near maximum depression. In another embodiment the discrete speed increase to the maximum tractive power speed occurs before maximum pedal depression. As the pedal approaches maximum depression, a threshold of increased resisting force occurs. Air pressure variation can be detected, electrically indicated, and that variable employed to modify prescribed engine speed.

Device for automatic actuation of an automobile clutch

An automatic clutch system is provided for use in a motor vehicle and has a control mechanism which responds to the position of the accelerator pedal and which also responds to first and second rotation speed sensing means connected to the engine shaft and the transmission shaft. In a preferred embodiment, the automatic clutch system is provided with a control mechanism which operates in a first mode when the vehicle is starting from a standing position to engage the clutch in a manner which keeps the engine in a specified speed range, which depends on accelerator lever position. The control mechanism operates in a second mode when the vehicle is shifted between gears in order to engage the clutch in a manner which provides a constant time gradient for the shaft speed difference selected in accordance with accelerator pedal position.

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Braunschweig, Germany

Frank Zimmermann