Patent ID: 7827947
Filing Date: 2010-11-09
Classification: F04C

Abstract:
1. A variable displacement pump for supplying a fluid pressure to a valve timing control device that has a lock state at engine start-up in which variable control of an open-and-closure timing of an engine valve of an internal combustion engine is restrained, and a release state after engine start-up in which the variable control of an open-and-closure timing of an engine valve is allowed by a fluid pressure, the variable displacement pump comprising: a pump unit including a suction portion, a discharge portion and a plurality of working fluid chambers, the pump unit being driven by the engine so as to discharge a working fluid that is introduced from the suction portion into the working fluid chambers, from the discharge portion according to change in volume of the working fluid chambers; and a chamber volume varying mechanism comprising: wherein the biasing force of the first biasing member is set such that the valve timing control device is shifted to the release state according to the discharge fluid pressure before the moveable member is displaced against the biasing force of the first biasing member.