Fuel supply system of internal combustion engine

摘要

A high-pressure pump is formed with a secondary suction passage, which branches from a fuel suction passage and communicates with a pump chamber. Check valves for preventing a backflow of fuel are disposed respectively in the secondary suction passage and a discharge passage. An electromagnetic valve for regulating a fuel discharge quantity is disposed in the fuel suction passage. Normal control for controlling the fuel discharge quantity by controlling opening timing and closing timing of the electromagnetic valve with respect to reciprocating movement of a plunger is performed when an engine rotation speed is higher than a predetermined value during operation of an engine. Valve closing control for holding the electromagnetic valve at a closed state is performed when the engine rotation speed is equal to or lower than the predetermined value.