QC/T 1125-2019Terms and definitions of automotive clutch systems (English PDF)

2.1 Automotive clutch

A component, which is located between the power source and the transmission, AND used to cut off and transmit power (hereinafter referred to as the clutch).

2.2 Clutch operation mechanism

A unit, which is connected by two or more components AND used to operate the clutch engagement and disengagement.

3.1 Friction clutch

A clutch, that relies on friction between the driving and driven parts to transmit power.

3.2 Mechanically controlled clutch

A clutch, that realizes the clutch function, under the direct action of a mechanical mechanism.

3.3 Hydraulically controlled clutch

A clutch, that performs a clutch function, under the action of hydraulic pressure.

3.4 Pneumatically controlled clutch

A clutch, that realizes the clutch function, under the action of compressed air.

3.5 Dry clutch

Clutches whose friction material does not operate in any fluid.

3.6 Self-adjusting clutch

A clutch, that can automatically adjust the working pressure to keep it constant, as the clutch friction pair wears.

3.7 Single plate clutch

A clutch, which has one disc assembly.

3.8 Double plate clutch

A clutch, which has two driven plate assemblies.

3.9 Multi-plate clutch

Clutches, which have more than two driven disc assemblies.

3.10 Diaphragm spring clutch

A clutch, that uses a diaphragm spring to generate pressing force.

4.2 Cover assembly

A component, which is composed of parts such as clutch cover, pressure plate, compression spring, AND is connected to the power source, to transmit or interrupt power (see Figure A.2 and Figure A.3 for example diagrams).

4.2.1 Pressure plate

The disc-shaped part, which serves as the active friction surface of the clutch to transmit the pressing force.

4.2.2 Intermediate pressure plate

The pressure plate, between the two disc assemblies, in a double plate clutch.

4.2.3 Cover

A part, that is connected to the power source AND plays a role in fixing and supporting the compression spring.

4.2.4 Support ring

A part, that limits the axial movement of the diaphragm spring and plays a supporting role.

4.2.5 Strap

An elastic part, that connects the pressure plate to the clutch cover.

4.2.6 Diaphragm spring

A disc spring, which has a separation finger structure, to compress the friction pair and separate it.

4.2.7 Release lever

A lever, that moves the pressure plate axially and plays a separation role.

4.2.8 Release lever support

A support on clutch, for the installation of the release lever.

4.2.9 Release lever adjusting nut

Nut, which is used to adjust the height of the clutch release lever.

5.1 Hydraulic clutch operation mechanism

A clutch operating mechanism, that transmits force and stroke hydraulically.

5.2 Mechanical clutch operation mechanism

A clutch operating mechanism, that mechanically transmits force and travel.

5.3 Hydraulic clutch operation mechanism by power assisting

Hydraulic clutch operating mechanism, which has power assisting device.

5.4 Mechanical clutch operation mechanism by power assisting

Mechanical clutch operating mechanism, which has a power assisting device.

6.8 Clutch slave cylinder push rod

A rod, that directly transmits the thrust and stroke of the clutch slave cylinder's piston.

6.9 Hydraulic release bearing

A device, which integrates the clutch slave cylinder and release bearing.

6.10 Clutch release cable

A cable, that transmits the force and stroke, which are generated by the clutch pedal, to the release device.

6.11 Clutch servo actuator

Clutch slave cylinder, which has power assisting function.

6.12 Clutch servo actuator by vacuum

A device, that realizes the power-assisting function, through the pressure difference generated by vacuum.