Multiple pump of reciprocating plunger type - has single cam operated rod driving plungers in two pump chambers

摘要

Two identical pump assemblies on opposite sides of the centre line each have a casing into which two valve assemblies are screwed. Each valve assembly has a ball loaded by a spring against a seat and arranged so that one acts as an inlet valve and the other as a discharge valve. The plunger extends out of the pump assembly and its opposite end forms the plunger of the opposite assembly. In its central portion between the assemblies it carries two flanges which ride on the surface of a cam. As the cam rotates it moves the plunger backwards and forwards to work both pumps together. The use of two opposing flanges makes the use of a return spring unnecessary.