Patent ID: 7909023

Claim:
A fuel supply system comprising: a fuel pump configured to supply fuel within a fuel tank to a side of an engine and having a vapor jet configured to discharge fuel vapor; a fuel vapor passage configured to permit the fuel vapor discharged from the vapor jet of the fuel pump to flow therethrough; a pressure regulating valve configured to regulate a fuel pressure within a pressure regulating chamber, into which the pressurized fuel discharged from the fuel pump is introduced, based on a pressure within a back pressure chamber, and to discharge surplus fuel; a surplus fuel passage configured to permit the surplus fuel discharged from the pressure regulating valve to flow therethrough; a throttle portion provided in the surplus fuel passage; a jet pump configured to be driven by a flow of the pressurized fuel and to permit the pressurized fuel discharged from the fuel pump to be introduced therein via a jet pump fuel passage; and a valve constructed to open and close the fuel vapor passage and the jet pump fuel passage in a manner opposite to each other based on a pressure of the surplus fuel within an upstream passage portion of the surplus fuel passage, the upstream passage portion being positioned on an upstream side of the throttle portion; wherein the valve is operable to close the jet pump fuel passage and to open the fuel vapor passage when the surplus fuel pressure is less than a threshold value, and the valve is operable to open the jet pump fuel passage and to close the fuel vapor passage when the surplus fuel pressure is equal to or higher than the threshold value.