Diesel engine fuel injection pump - has outlet throttled during part of stroke but throttle closed during cold-start by rotation of piston

摘要

The Diesel engine fuel injection pump comprises a cylinder (1) with a piston (2,5,9,8) which defines a pump chamber (10,10a,10b) with inlet ports (18,19) and outlet ports (15) leading to a pressure chamber (16). The piston has a portion (5) with one set of faces (3,4) controlling the inlet ports (18,19) and a portion (8) with a second set of faces (6,7) controlling the outlet ports (15). These faces are arranged such that, when the ports are disconnected by the first faces (3,4) the second faces, (6,7) disconnect the ports (15) except for a throttle connection (13,14 via 11,12) arranged in the piston. This throttle connection is closed during engine start-up by rotation of the piston about its axis.