VARIABLE DISPLACEMENT PUMP

摘要

PROBLEM TO BE SOLVED: To increase the discharge amount of a pump in a well responsive manner even when a hydraulic pressure on the discharge side of the pump sharply rises. SOLUTION: A rolling supporting face 41 made as a plane extending to a tangential direction in an axial view is formed on a pump body 2 on the side of a discharge port 10, only at one side portion apart from an axial center R of a rotor 5 to a second fluid pressure chamber 13. The rolling supporting face 41 is inclined so that the axial center of a cam ring 4 is moved to the discharge port 10 by the rolling of the cam ring 4 in the direction of increasing the discharge amount of the pump.