Fuel injection pump for internal combustion engines

Claim 1

A fuel injection pump for internal combustion engines comprising a pump housing, a pump cylinder in said pump housing, a reciprocating pump piston in said pump cylinder which encloses a work chamber, a suction chamber in said pump housing, an intake bore in said pump housing and said pump cylinder through which said work chamber can be supplied with fuel from said fuel suction chamber in said pump housing during an intake stroke, a valve in said intake bore between said fuel suction chamber and said work chamber for shutting off a fuel supply from said fuel suction chamber to said work chamber, said work chamber being connected during at least a portion of a supply stroke of said pump piston with at least one fuel injection line in said pump housing that leads to an injection valve of an engine, a longitudinal conduit in said pump piston which leads exclusively from said work chamber to a radially extending relief opening located in the pump piston, said relief opening being closable by means of a quantity adjusting device that is displaceable on a portion of said pump piston which protrudes into said fuel suction chamber of said pump housing that is filled with fuel under pressure and beyond a pump piston stroke determined by an axial position of said quantity adjusting device, said relief opening being adjustable into communication via a control edge of said quantity adjusting member with said suction chamber, and a check valve closable upon a suction stroke of the pump piston is disposed on the periphery of said quantity adjusting device in a connection between said work chamber and said suction chamber.