Apparatus to propel ball with different force

摘要

The ball is propelled by a pusher (2) which is introduced into a tube (1) that holds a spring (10) A compartment (3) is fixed to the tube and holds a push button (4) that releases the pusher. The other end of the tube is closed by a stopper (11). The central rod (6) of the pusher has three thinner zones (7) which form stops (8) to vary the force of the pusher. A washer (9) is screwed to the end of the rod to hold it in the tube and against which the spring presses.