Fuel injection pumping apparatus

Claim 1

A fuel injection pumping apparatus comprising a rotary distributor member located in a housing and arranged in use to be driven in timed relationship with an associated engine, outlet ports in the housing for connection in use to injection nozzles respectively of the associated engine, a pair of pumping plungers slidable within respective communicating radial bores in the distributor member, a delivery passage communicating with said bores and arranged to register in turn with said outlet ports during successive inward movements of the plungers, means for supplying fuel to said bores, annular cam means for imparting inward movement to the plungers, said bores being defined by a diametrically disposed drilling and said cam means comprising a first annular cam ring for actuating one plunger and a second annular cam ring for actuating the other plunger, each cam ring having a cam lobe or cam lobes equal in number to the number of cylinders of the associated engine, cam followers associable with the plungers respectively, said cam followers being located at the outer ends of the plungers respectively, said cam followers being constructed so that one follower and the associated plunger is actuated by the lobe or lobes on the first of said cam rings and the other follower and the associated plunger is actuated by the cam lobe or lobes on the second of said cam rings, the cam rings being angularly displaced such that inward movement is imparted to the plungers at the same time during rotation of the distributor member.