Patent ID: 8459973
Filing Date: 2013-06-11
Classification: F04C

Abstract:
1. A vane pump comprising: a housing comprising a substantially circular pump chamber; a rotor that rotates about a position eccentric with respect to a center of the pump chamber; a vane that is rotated by the rotor and that always partitions the pump chamber into a plurality of spaces; an oil supply passage that intermittently communicates with the pump chamber by the rotation of the rotor; and a gas passage that makes the pump chamber and an outer space communicate with each other when the oil supply passage communicates with the pump chamber by the rotation of the rotor, wherein the oil supply passage further comprises: a diameter direction oil supply hole provided at a shaft part of the rotor in a diameter direction thereof; and an axial direction oil supply groove that is provided in the housing to communicate with the pump chamber, and with which an opening of the diameter direction oil supply hole is made to intermittently overlappingly communicate by the rotation of the rotor, the gas passage comprises a gas groove whose one end is made to communicate with the outer space, the gas groove being formed on an outer peripheral surface of the rotor, and the other end of said gas groove is made to intermittently overlappingly communicate with the axial direction oil supply groove by the rotation of the rotor, a width of the gas groove is formed larger than that of the opening of the diameter direction oil supply hole based on a circumferential direction of the shaft part of the rotor, is also formed extending to positions anterior to and posterior to both end edges of the opening of the diameter direction oil supply hole, and is also formed smaller than a width of the axial direction oil supply groove, and the gas groove communicates with the axial direction oil supply groove when the rotation of the rotor is stopped in a state where the opening of the diameter direction oil supply hole slightly communicates with the axial direction oil supply groove.