It is a mechanical device, which is widely used in automobiles for the purpose of engaging and disengaging the driving and the driven shafts instantaneously, at the will of the driver or the operator. The driving shaft is the engine crankshaft and the driven shaft is the gearbox-driving shaft. This means that the clutch is situated between the engine crankshaft or flywheel mounted on it, and the gearbox.In automobile, gears are required to be changed for obtaining different speeds, and it is possible only if the driving shaft of the gearbox is also required to be stopped for a while without stopping the engine. These two objects are achieved with the help of a clutch.
Broadly speaking, a clutch consists of two members; one fixed securely, to the crankshaft or the flywheel of the engine so as to rotate with it an the other mounted on a splined shaft means to drive the gear box so that this could be slided and engaged or disengaged as the case may be with the member fixed with engine crankshaft.