Accumulator fuel injection system

Abstract

An object of the present invention is to provide an accumulator fuel injection system comprising a pressure increasing unit 7 and a pressure increasing common rail 6, in which leaked fuel is recirculated from a high pressure side to a low pressure side, and which is capable of reducing the amount of fuel that must be delivered under pressure by a low pressure pump 3. The focus of the present invention is to return high pressure leaked fuel to between the low pressure pump 3 and a high pressure pump 5. The accumulator fuel injection system of the present invention comprises the low pressure pump 3 for delivering fuel under pressure from a fuel tank 2, the high pressure pump 5 for changing the fuel from the low pressure pump 3 into high pressure fuel, an accumulator (common rail) 6 for accumulating the high pressure fuel from the high pressure pump 5 at a predetermined pressure, an injector 8 which is connected to the accumulator 6 for injecting the high pressure fuel, and the pressure increasing unit 7 which is provided between the injector 8 and the accumulator 6 for further increasing the pressure of the high pressure fuel. Leaked fuel from the pressure increasing unit 7 may be recirculated to the downstream side of the low pressure pump 3 through a unit leakage passage 17.

Dependencies are inferred from the claim text.