UNIT INJECTOR OPTIMIZED FOR REDUCED EXHAUST EMISSIONS

摘要

A diesel unit injector of the EMD type is provided with a tip (30a) whose radius (R4) is centered below the center of radius (R5) of the sac which it encloses, and the sac volume is minimized. Th e lower face (31a, 33a) of the nozzle body (10a) of the injector is faired in such a manner as to maintain a strong wall cross section. A system utilizing a set of potential substitute spring seats (S) is used to reset the opening pressure, as upon rebuilding, within narrow tolerances. The nozzle body (10a) is shortened and the check valve cage (6a) correspondingly lengthened to reduce the length of the injector valve proper. Trapped volume is reduced consistently with fuel flow requirements.