MOTOR TYPE FUEL PUMP FOR VEHICLE

摘要

PROBLEM TO BE SOLVED: To solve the following problems in a motor type fuel pump mounted in a fuel tank: a relief valve for relieving excessive pressure of fuel delivered and a one-way valve for preventing fuel in a fuel supply pipe from flowing backward are provided for the fuel pump, and a pressure regulating valve for maintaining a predetermined fuel pressure is provided downstream the one- way valve; these arrangements result in the heavier and bigger fuel pump; and pressure regulating process is also troublesome. SOLUTION: A relief valve provided with a pressure regulating function 16 is provided integrally with a one-way valve 11 provided at a delivery port 9 of a fuel pump 1. The relief valve provided with the pressure regulating function 16 closes a valve seat 19 formed in an opening in a relief flow path communicating with a valve chamber 14 of the one-way valve 11 using a valve body 17 urged to a predetermined pressure by a spring 18 to maintain fuel in a fuel supply pipe 3 at a predetermined pressure. The relief valve 16 is also operated when pressure of fuel from the pump is excessive. This eliminates the need for a conventional relief valve provided in the fuel pump and allows these devices to be built compactly. COPYRIGHT: (C)2003,JPO