The figure shows the vacuum clutch mechanism. This type of clutch utilizes the present vacuum within the engine manifold to work the clutch. The vacuum clutch contains a reservoir, non-return valve, vacuum cylinder with piston, and solenoid valve.  The springs preserve the flywheel relocating forward or backward through the frictional https://franciscooqonj.bloguetechno.com/what-does-clutch-kereta-mean-68165191