Patent ID: 6450788
Filing Date: 2002-09-17
Classification: F04B

Abstract:
A piston pump (1) for high-pressure fuel delivery in rail injection fuel systems of internal combustion engines comprising:a pump housing (2), said pump housing (2) being closed off from an internal chamber (10) by means of a first plate (16), which first plate essentially rests against the pump housing completely and in which a cylinder chamber (17) is embodied that contains a pump piston (6), said first plate (16), on the side oriented away from said housing, being covered by a second plate (18) that closes off said cylinder chamber (17), a first check valve (11) between said first plate (16) and said second plate (18), said first check valve being connected to said cylinder chamber (17), said second plate (18) having a first conduit (29) formed thereon extending predominantly in its plane and carrying low-pressure fuel, which first conduit starts at said pump housing (2) and ends at said first check valve (11), a second conduit (31), which carries high-pressure fuel leading from the cylinder chamber (17) and in its continued course, has a second check valve (12) after which said second conduit (31) continues inside said pump housing (2), low-pressure seals (37, 38, 39) and high-pressure seals (40, 41) being disposed between said pump housing (2) and said plates (16, 18), said first plate (16) and said second plate (18) being embodied so that they essentially rest completely against each other, said first conduit (29) having a section which passes through said first plate (16), at a location between said pump housing (2) and said second plate (18), said second check valve (12) being disposed between said first plate (16) and the pump housing (2), and said second conduit (31) being embodied in said first plate, between said cylinder chamber (17) and the second check valve (12).