Hydraulic power transmission joint

摘要

A valve block coupled to a rotor is provided with a drain mechanism that includes a drain pin adapted to open and close a drain hole. The drain pin is incorporated in a drain plug by providing a support by a return spring. The drain pin has an orifice for generating a flow resistance. One end turn portion of the return spring is press fitted into the interior of the drain pin having the orifice, while the other end turn portion of the return spring is press fitted into the interior of a limiter plug having a limiter pin, whereby the drain pin is rotationally positioned to alleviate cavitation noises.