The figure shows the vacuum clutch system. This kind of clutch works by using the existing vacuum while in the engine manifold to work the clutch. The vacuum clutch is made up of a reservoir, non-return valve, vacuum cylinder with piston, and solenoid valve.  The springs hold the flywheel transferring https://clutchkereta33321.blogrenanda.com/39247128/the-ultimate-guide-to-clutch-plate