Cam and lever drive system for reciprocating pump with variable piston stroke incorporates intermediate lever with movable fulcrum point bearing against spring-loaded lever

摘要

The drive system (1) incorporates a shaft (17) carrying an oval cam (13) with two projecting lobes (15) pushing an intermediate lever (23). The lever pivots on a fulcrum (27) on the end of an adjustment lever (25) mounted on a rotatable shaft (29). The surface remote from the cam bears on a roller (35) on a spring-loaded (31) lever (19). A contoured cam surface (39) on the end of the lever bears against a roller (43) on a lever (41,47) which moves a spring-loaded (49) piston (11). Movement of the adjustment lever changes the swing range of the intermediate lever.