Patent ID: 7717091

Claim:
A fuel supply system comprising: a fuel tank for storing fuel; a fuel pump for supplying the fuel inside the fuel tank to outside of the fuel tank; a pressure regulator comprising a fuel pressure regulating chamber and a control pressure chamber defined by a movable partition wall and each configured for introducing a portion of the fuel discharged from the fuel pump; wherein the pressure regulator regulates the fuel pressure inside the fuel pressure regulating chamber and returns surplus fuel into the fuel tank; a valve device being controlled by the control device for changing the fuel pressure supplied to outside of the fuel tank by selectively switching between the introduction of the fuel and the introduction of air into the control pressure chamber of the pressure regulator; and a pressure relief valve for regulating the fuel pressure inside the control pressure chamber of the pressure regulator to be below a predetermined value; wherein the fuel pump can pressurize the fuel to a predetermined pressure, and the pressure of the fuel introduced into the control pressure chamber is lower than the predetermined pressure.