摘要 |
PROBLEM TO BE SOLVED: To provide a fuel feed system that prevents a fuel leakage from an operating portion side to a pump drive side and a leakage of fuel oil and lubricating oil from a fuel pump to the atmosphere by eliminating a pressure difference between the drive unit side of the fuel pump and the pump side. SOLUTION: In a fuel feed system, a return flow passage 14, one end of which is connected to a top 2b of a fuel tank 2, is connected to a void 8a formed at a drive unit 3 side of a cylinder 8, and a sealing member 11 is arranged between a plunger 9 and a cylinder pressing part 8b at the drive unit 3 side rather than the void 8a, thus cutting off a reciprocating motion mechanism chamber 7a that has accommodated a reciprocating motion mechanism 7 together with lubricating oil. A motor 5 for driving and the reciprocating motion mechanism 7 are sealingly surrounded by outer enclosures 10a, 10b so that they exist in the same space, as well as an encapsulated space and a space 8a including the return flow passage 14 are interconnected. COPYRIGHT: (C)2008,JPO&INPIT |