Method of and apparatus for preventing shifts of reference positions of friction clutches

A method of ascertaining and regulating shifts of reference position of an actuator-operated clutch in the power train of a motor vehicle wherein the shifts are caused by axial displacements of at least one of the input and output shafts of the clutch relative to the other shaft, comprising:

• a first step of routinely ascertaining the reference position of the clutch;
• a second step of routinely memorizing and thus actualizing information pertaining to the ascertained reference position;
• a third step of determining operational parameters which initiate shifts of reference position of the clutch;
• a fourth step of conforming said first and second steps to the shifted reference position when the determined operational parameter exceeds a predetermined threshold value;
• and
• a fifth step of ascertaining and regulating shifts of reference position of an actuator-operated clutch in the power train of a motor vehicle in which the output shaft of the clutch is the torque-transmitting input shaft of a change-speed transmission, wherein said third step includes determining the torque which is being transmitted by the output shaft of the clutch.

A method of ascertaining and regulating shifts of reference position of an actuator-operated clutch in the power train of a motor vehicle wherein the shifts are caused by axial displacements of at least one of the input and output shafts of the clutch relative to the other shaft, comprising:

• a first step of routinely ascertaining the reference position of the clutch;
• a second step of routinely memorizing and thus actualizing information pertaining to the ascertained reference position;
• a third step of determining operational parameters which initiate shifts of reference position of the clutch;
• a fourth step of conforming said first and second steps to the shifted reference position when the determined operational parameter exceeds a predetermined threshold value;
• and
• a fifth step of establishing a hydraulic force transmitting path between the actuator and the clutch;
• wherein said first step includes a snifting operation.

An arrangement for regulating the shift of a reference position of an actuator-operated torque-transmitting clutch in the power train of a motor vehicle wherein the shift is caused by axial movements of at least one of an input shaft of the clutch and an output shaft of the clutch relative to the other thereof, comprising:

• a connection between a mobile multiple-position force-transmitting operating member of the actuator and a displaceable clutch setting member;
• a control unit for the actuator;
• a plurality of signal-transmitting monitoring devices operatively connected with said control unit and including a sensor arranged to transmit to the control unit signals denoting the positions of said operating member;
• means for ascertaining the force being transmitted by said operating member to displace said setting member;
• and
• means for monitoring the torque being transmitted by said clutch, said control unit being arranged to routinely ascertain the reference position of said clutch, to routinely memorize and to thus actualize information pertaining to the ascertained reference position, to determine operational parameters which initiate shifts of reference position of the clutch, and to conform the reference position and the memorized information to the shifted reference position when the determined operational parameter exceeds a predetermined threshold value.