Fuel injection apparatus for engines and method of operating the apparatus

摘要

A fuel injection apparatus for engines is provided, with which occurrence of cavitation erosion on constituent parts of the high pressure fuel pump and fuel feed line to the pump in the apparatus is suppressed and high durability is attained even in the case of a high pressure fuel pump increased largely in capacity. Each of high pressure fuel pumps (20) to supply high pressure fuel to a common rail (7) comprises an electromagnetic valve (1) which is controlled by a controller (100) such that fuel is discharged from the plunger room (3) by closing the electromagnetic valve (1) in the up stroke of the plunger (2) until the plunger reaches its top dead center, the electromagnetic valve (1) is kept closed for some period in the down stroke of the plunger (2), then the electromagnetic valve (1) is opened to allow the plunger room (3) to be communicated with a fuel feed/spill passage (20b).