Patent ID: 7401594
Filing Date: 2008-07-22
Classification: F02M,F04B

Abstract:
1. A high pressure fuel pump comprising: a plunger being arranged for reciprocating motion, a pressure chamber for pressurizing fuel in collaboration with reciprocating motion of the plunger, which pumps the fuel in the pressure chamber, an intake valve at an inlet port of the pressure chamber, a delivery valve at an outlet port of the pressure chamber, a pump body housing the pressure chamber, plunger, intake valve and delivery valve, a low pressure fuel passage positioned upstream from the intake valve in the pump body, a damper housing portion located along the low pressure fuel passage, a damper installed in the damper housing portion comprising at least one double metal diaphragm type damper in which two rim-welded metal diaphragms form a sealed space between there with a gas in the sealed space, such that fuel pressure pulsation caused by the reciprocating motion of the plunger exerts on the both sides of the double metal diaphragm-type damper, and a guide for limiting a radial position of the double metal-type diaphragm, which guide has a retaining portion formed with an shelf annular located at a side of a welded rim portion of the two metal diaphragms, such that the annular shelf presses completely around a circumference portion of the diaphragm, which portion is located radially inwardly of the welded rim portion.