The figure demonstrates the vacuum clutch mechanism. Such a clutch employs the present vacuum from the motor manifold to work the clutch. The vacuum clutch consists of a reservoir, non-return valve, vacuum cylinder with piston, and solenoid valve.  But let us stick to the topic of cars currently! In this https://emiliofpuyc.get-blogging.com/33544599/the-ultimate-guide-to-clutch-plate