Variable capacity vane pump

TL;DR: In this article, a variable capacity vane pump is used to supply operating oil to a power steering device and is equipped with a flow volume control valve that controls the amount of operating oil discharged by the pumping element.

Abstract: A variable capacity vane pump 1 that supplies operating oil to a power steering device and is equipped with: a pump housing 2, comprising a bottomed cylindrical front housing 5 and a rear housing 6 that closes off the front housing; a pumping element 3 that is housed within the pump housing, and communicates with a suction passage 23 and a discharge passage 30 to draw in and to discharge the operating oil; and a flow volume control valve 33 that controls the amount of operating oil discharged by the pumping element. A pressure-sensitive valve 50, which changes the flow path cross-sectional area of the discharge passage so as to increase the discharge amount of the pumping element in conjunction with an increase in the load pressure of the power steering device, is provided midway along the discharge passage, on the bottom wall portion 5b of the front housing. Thus, when applied to a power steering device, an increase in the size of the device can be avoided while reducing energy loss.