Patent ID: 7878779
Filing Date: 2011-02-01
Classification: F01C,F04C

Abstract:
1. A vane pump comprising a pump housing containing a rotor driven in rotary fashion by a drive shaft, a number of grooves formed in the rotor and distributed over its circumference, the grooves extending at least essentially in the radial direction in relation to the rotation axis of the rotor, a wing-shaped delivery element guided in sliding fashion in each groove, a circumferential wall surrounding the rotor and extending eccentrically in relation to its rotation axis, against which wall the radially outer ends of the delivery elements rest, housing end walls of the pump housing that adjoin the rotor in the direction of its rotation axis, the delivery elements being adapted to deliver medium from a suction region to a pressure region offset from it in the rotation direction of the rotor upon rotation of the rotor, an annular groove extending over part of the circumference of the rotor in one of the housing end walls, the annular groove being situated opposite the inner regions that are delimited in the grooves of the rotor by the delivery elements, the annular groove extending over the entire circumference of the rotor, a pressure groove in said housing end wall in said pressure region, and a connecting groove in said housing end wall providing communication between the annular groove and the pressure groove in said housing end wall, the connecting groove extending from the pressure groove radially inward in the rotation direction of the rotor to the annular groove, wherein the connecting groove extends in spirally curved fashion.