| 摘要 |
PURPOSE:To energize a needle valve in the valve closing direction by oil pressure difference so as to heighten the valve closing responsiveness of a valve body by providing a pressure lead-in passage communicated with at least one of an armature chamber and a needle valve chamber, and a check valve opened at the relief time of fuel. CONSTITUTION:An electronic control unit 22 in a fuel injection device determines fuel injection timing and fuel injection quantity according to the operating state and controls current application to the solenoid 25b of an electromagnet 25 in a solenoid valve. In this solenoid valve, a needle valve 27 is disposed at the center of a valve body 31 and vertically displaced through an armature 26 by current application to the solenoid 25b. An armature chamber 63 is made to have the same pressure as a low pressure chamber 18 by a pressure lead-in passage 54. A check valve 53 opened at the relief time of fuel is provided at the intermediate part of relief passages, downstream of the needle valve 27. When the fuel pressure is lowered, the needle valve 27 is pushed down by spring pressure, and the check valve 53 is closed when the force-feed of a plunger 6 is terminated. |
