Patent ID: 6123532
Filing Date: 2000-09-26
Classification: F01C,F04C

Abstract:
A vane pump comprising a rotor rotatable around an axis, a plurality of vanes supported in the rotor to be movable in the radial direction, a cam ring around the rotor and the vanes and forming at least one suction region and one pressure region at the rotor; the rotor and cam ring having opposite lateral sides,a pressure plate at at least one lateral side of the rotor, the pressure plate being shaped and positioned for forming a lateral boundary for the rotor at the suction and the pressure regions and at the cam ring, the pressure plate having an inward side which faces toward and forms a lateral boundary surface of both the suction and the pressure regions of the rotor and at the cam ring, and the pressure plate has an opposite outward side facing away from the suction and pressure region, wherein when the vane pump is operating for drawing fluid into the suction region and pumping it from the pressure region, the outward side of the pressure plate is loaded by pressure;the pressure plate being shaped so that the inward side facing the rotor is concave when there is no pressure in the vane pump and the pressure plate is of such material which is related to the pressure to which the outward side of the pressure plate is exposed that the pressure plate is flattened toward the rotor to reduce the concavity of the concave inward side of the pressure plate when the rotor is rotating and the outward side of the pressure plate is loaded by pressure.