Cam 1 rotates about fixed axis A. Punch 3 slides in fixed guide B. Plunger (fol- lower) 2 reciprocates in fixed guide C and carries roller 5 which rolls a long the working surface of cam 1. Plunger 2 is actuated by spring 4. When cam 1 rotates, roller 5 is raised by the cam and then suddenly dropped so that spring 4 pushes plunger 2 which strikes punch 3 and makes a hole in the stock.
$3166$SmC,FD$