FUEL SUPPLY DEVICE OF FUEL INJECTION TYPE ENGINE

摘要

PURPOSE: To prevent a rise of temperature of a low pressure fuel pump and a high pressure pump and a rise of temperature of fuel by providing a cooling fuel passage which is branched from a fuel supply passage between an outlet side of the low pressure fuel pump and an inlet side of the high pressure pump and is connected to a cooling chamber of the high pressure pump so as to cool down a rise of temperature of the high pressure pump by fuel having low temperature. CONSTITUTION: The fuel which is sucked from the inside of a fuel tank 10 by a low pressure fuel pump (feed pump) 2 is fed under pressure to a high pressure pump 5 via a fuel supply passage 11, is pressurized furthermore, and is fed to a fuel injection valve 6. The fuel which overflows from the fuel injection valve 6 passes a return passage 12 and a high pressure adjusting valve 8, joins cooling fuel in a cooling fuel outlet passage 24 which passes a low pressure adjusting valve 22, and is cooled by a fuel cooler 23 to return the fuel into the fuel tank 10. The fuel of which stream is divided from the fuel supply passage 11 and flows in a cooling fuel passage 21 enters a cooling chamber 51 of the high pressure pump 5 to cool the high pressure pump 5, and then joins return fuel in the return passage 12 after passing the low pressure adjusting valve 22.