PRESSURE NON-LOAD FEED VALVE

摘要

PROBLEM TO BE SOLVED: To provide a pressure unloading feed valve of an improved shape. SOLUTION: A pressure unloading feed valve 10 comprising two parts for a fuel injection pump is constituted of an annular valve member 20 in which a plunger 26 is slidable. The valve member is biased through engagement with a valve seat 15 by a spring 22 and is lifted from the seat by fuel under pressure fed by the pump. The spring biases the plunger in the direction away from the seat and following closure of the valve member the plunger is moved in the direction towards the seat to allow relief of fuel under pressure from the pipeline 18 connecting the valve 10 with a fuel injection nozzle 19. After a predetermined movement of the plunger against the spring, damping means in part defined by a piston 23 on the plunger, acts to damp the further movement of the plunger.