3.1. General data

Coupling is intended for short-term dissociation of the engine from the transmission at the time of gear shifting and provides smooth start-off from the place.

Coupling consists of a press drive plate, the conducted disk and the release bearing.

Press the disk is screwed rigidly together with a flywheel which is in turn attached to the engine crankshaft. Between a press disk and a flywheel there is a conducted disk which is pressed by a press disk to a flywheel. The conducted disk sits on vents of a power shaft of the transmission.

By pressing a coupling pedal (coupling is switched off) the release bearing, under impact on it of the hydraulic or mechanical drive and lever of switching off, nestles on springs of a press disk. Press the disk is weakened and the conducted disk does not nestle on a flywheel any more. The power transmission between the engine and the transmission is interrupted.

Depending on equipment of the car, the drive of coupling is carried out by a rope or hydraulic system: the piston of the working cylinder of a hydraulic system rests against the lever of switching off. When pressing a coupling pedal in the main cylinder located in the car in the driver's legs pressure which on a hydraulic actuator is transferred to the working cylinder attached to the transmission is created. The piston of the working cylinder through a fork of switching off presses the switching off bearing to membrane springs of a press disk and the disk departs.

The hydraulic system of coupling uses brake fluid and is supplied with it from the general broad tank of the brake system.

If the pedal of coupling comes back to a starting position (coupling is included), then press the disk presses the conducted disk to a flywheel, the power transmission is restored as the pressed conducted disk is rigidly connected by face connection with a transmission shaft.

At each inclusion and switching off of coupling, as a result of friction, frictional slips on the conducted disk are used up. The conducted disk is the worn-out part, however middle service life makes it about 100 000 km. Wear depends generally on loading (driving with the trailer) and driving manners. Coupling does not demand leaving as it is regulated automatically.