Unit for delivering fuel from the fuel tank to the internal combustion engine of a motor vehicle

摘要

PCT No. PCT/DE91/00449 Sec. 371 Date Dec. 28, 1992 Sec. 102(e) Date Dec. 28, 1992 PCT Filed May 27, 1991 PCT Pub. No. WO92/00449 PCT Pub. Date Jan. 9, 1992.A unit for delivery of fuel from the fuel tank to the internal combustion engine of a motor vehicle includes a feed pump which is arranged in the fuel tank and constructed as a flow pump with substantially circular-cylindrical impeller driven in rotation in a correspondingly circular-cylindrical pump chamber. In at least one of the two chamber end walls, at least one approximately annular delivery duct which is groove-like in cross section extends from a suction opening which opens into the pump chamber to a pressure opening leading out of the latter. This end wall of the chamber is penetrated in the region of the pressure opening by a bore hole connecting the pump chamber with a region of the system in which low pressure prevails. Gas bubbles can be removed from the pump and accordingly from the delivery path in a particularly reliable and simple manner in that this bore hole is situated in a sealing surface which defines the delivery duct in the radial direction with reference to the axis of rotation of the impeller.