Chamber-controlled fuel injection pump for internal combustion engines

Claim 1

An oblique-edge-controlled fuel injection pump for internal combustion engines having an axially and rotationally movable pump piston guided in a pump cylinder, which pump piston includes two diametrically opposite recesses, delimited by oblique control edges, in its outer surface, which recesses are in continual communication with the pump operating chamber and can be connected with a low pressure chamber through two control bores lying opposite each other in the wall of the pump cylinder to terminate the effective fuel delivery stroke, and of which the first recess can be opened shortly before the second by its associated control bore and serves as an element of a connecting line from the pump operating chamber to the low pressure chamber which is provided with a throttle point, the improvement wherein said first recess is connected exclusively with a blind-bore type longitudinal bore through a cross bore, said longitudinal bore being arranged to extend from the pump operating chamber into said pump piston and that said cross bore is formed to provide a throttle bore whose diameter (D 1 ) is not more than one fourth of the diameter (D 2 ) of one of said control bores.