Piston type liquid fuel pump with an improved outlet valve

摘要

A fuel injection system for injecting gasoline or other fuel directly into the combustion chambers of an internal combustion engine includes a fuel pump having a fixed barrel member therein which has a plurality of bores forming cylinders extending therethrough. A pumping piston extends into one open end of each of the cylinder bores. The piston is supported for reciprocal movements as produced by an input mechanism, such as a shaft and swash plate. A fluid inlet passage and inlet check valve are positioned at one end portion of each piston so that fluid can be drawn into the pumping chamber formed by the cylinder bore and piston. The other open end of the cylinder bore in the barrel member serves as an outlet for fluid from the pumping chamber and a flat reed valve portion of an outlet valve plate overlies the open end to prevent fludi from reentering the pumping chamber during an inletting stroke. This reed valve does not move through and agitate fuel as a sliding type valve would and thereby does not generate significant heat which would tend to vaporize fuel and be detrimental to pumping of liquid fluid.