VARIABLE CAPACITY TYPE VANE PUMP DEVICE

摘要

PURPOSE:To prevent a working oil (discharge oil) from presenting a counter- stream phenomenon likely when a selector valve changes over the pump discharge capacity from low to high output. CONSTITUTION:A check valve 32 consisting of a ball and a spring and admitting the discharge oil flowing from a specific (No.2) discharge port 31' situated on the side continued to a selector valve 1 to a pressure chamber 27 is installed at that opening of the port 31' which is leading to the pressure chamber 27. It may happen in the low output condition that a specific suction port 41' and specific discharge port 31' are put in communication with each other due to shortage of the vane hopout force, but occurrence of counter-stream of the working oil on the occasion of changing-over from low to high output is prevented owing to the action of the check valve 32.