| 摘要 |
PROBLEM TO BE SOLVED: To provide a fuel pump for a common-rail-type fuel injection device which realizes supply of high-pressure fuel in a simple structure, which has been traditionally difficult. SOLUTION: In a fuel pump 10 used for a common-rail-type fuel injection device, when a distribution rotor 30 of this fuel pump 10 rotates around its axis and a supply port 31b of a supply passage 31 is communicated with a driving chamber 28, a step piston 21 moves in the direction that a pump room 27 becomes narrow, fuel in the pump room 27 is highly pressurized and supplied to a common rail. When discharge port 32a of a discharge passage 32 is communicated with the driving chamber 28, the step piston 21 moves in the direction that a pump room 27 becomes wide, and fuel is sucked into the pump room 27 from a fuel tank. |
