Abstract: The invention relates to a vane pump comprising a rotor which is arranged therein, rotatably driven by a drive shaft. The rotor is provided with several grooves which are distributed through the circumference thereof and which extend substantially radially with respect to the axis of rotation of the rotor. In each groove a blade-shaped conveying element is slidingly guided. The end walls of the pump housing are adjacent to the rotor in the direction of the axis of rotation thereof. At least one ring-shaped groove surrounding the axis of rotation of the rotor is embodied in at least one front side of the rotor. The ring-shaped groove is connected to lower areas restricted by the blades in the grooves of the rotor, and to pressure areas. In a preferred embodiment, the ring-shaped groove is formed in the rotor by shaping.

Abstract: The invention relates to a vane pump comprising a rotor which is arranged therein, rotatably driven by a drive shaft. The rotor is provided with several grooves which are distributed through the circumference thereof and which extend substantially radially with respect to the axis of rotation of the rotor. In each groove a blade-shaped conveying element is slidingly guided. The end walls of the pump housing are adjacent to the rotor in the direction of the axis of rotation thereof. At least one ring-shaped groove surrounding the axis of rotation of the rotor is embodied in at least one front side of the rotor. The ring-shaped groove is connected to lower areas restricted by the blades in the grooves of the rotor, and to pressure areas. In a preferred embodiment, the ring-shaped groove is formed in the rotor by shaping.