Fuel injection pump for IC engine - has additional support to shaft provided by cylindrical surfaces on cams

摘要

A fuel injection pump has a shaft (12) running through a casing (11). The shaft carries a series of cams (16) spaced axially along it. Each cam operates a pump plunger (19) against a spring. A part (16) of the surface of each cam is circular and the other part (15) is undercut from this. The casing (11) has a projecting lug (23) under each cam and the inside face (24) of this lug is machined as a cylindrical bore. The cam is thus supported in the lug for part of its revolution. The cylindrical sections of successive cams are displaced circumferentially from each other so that there is always at least one cam supported in the casing. this provides support to the shaft between the two end bearings.