Vane pump

Abstract

A vane pump includes a high-pressure chamber formed as a groove in a bottom portion of a pump-accommodating concave portion. The working fluid is discharged from a plurality of discharge ports leading to the high-pressure chamber. A high-pressure passage has an opening portion opening to the high-pressure chamber and guides the working fluid to the outside of the high-pressure chamber. In the vane pump, one of the plurality of discharge ports is arranged so as to face the opening portion of the high-pressure passage, and the flow-passage cross-sectional area of the high-pressure chamber is smaller than the total flow-passage cross-sectional area of the plurality of the discharge ports.

1 . A vane pump comprising: a rotor linked to a driving shaft and having a plurality of vanes on an outer circumference thereof;
 a cam ring configured to accommodate the rotor and define pump chambers in a space therein;   a pump body provided with a pump-accommodating concave portion into which the rotor and the cam ring are accommodated;   a side plate provided between the rotor and the pump body;   a plurality of discharge ports formed in the side plate and configured to discharge working fluid from the pump chambers;   a high-pressure chamber in a form of a groove formed in a bottom portion of the pump-accommodating concave portion, the working fluid discharged from the plurality of discharge ports being led to the high-pressure chamber; and   a high-pressure passage having an opening portion opening to the high-pressure chamber, the high-pressure passage being configured to guide the working fluid to outside of the high-pressure chamber, wherein   one of the plurality of discharge ports is arranged so as to face the opening portion of the high-pressure passage, and   a flow-passage cross-sectional area of the high-pressure chamber is smaller than a total flow-passage cross-sectional area of the plurality of discharge ports.   
     
     
         2 . The vane pump according to  claim 1 , wherein
 the plurality of discharge ports includes a first discharge port and a second discharge port, the first discharge port being arranged so as to face the opening portion of the high-pressure passage and the second discharge port being arranged at a position remote from the opening portion of the high-pressure passage,   the high-pressure chamber is formed in an annular shape such that a flow of the working fluid that has been guided from the second discharge port to the high-pressure chamber is divided into two flows flowing into a first high-pressure chamber and a second high-pressure chamber in the high-pressure chamber, and thereafter, the flows are mixed at the opening portion of the high-pressure passage, and   a total flow-passage cross-sectional area of the first high-pressure chamber and the second high-pressure chamber is larger than a flow-passage cross-sectional area of the second discharge port.