| 摘要 |
PURPOSE:To improve the injection characteristic and simplify the internal construction by assuring reliable operation of a solenoid valve and placing a change-over valve and the solenoid valve in the coaxial and adjacent arrangement. CONSTITUTION:When a solenoid valve 5 is lifted upward, the outlet opening of a change-over valve chest 18 of a change over valve 4 is opened. Working oil inside the change-over valve chest 18, at this time, flows into a servo piston chamber 16. Fuel oil inside a fuel in a fuel inlet passage 15, at the same time, flows into the change-over valve chest 18. Since the bore of a change-over valve chest inflow opening 36 is smaller than that of a change-over valve chest outflow opening 37, a pressure of the fuel inside the change-over valve chest 18 will not balanced with a pressure of the fuel inside the fuel inlet passage 15 so that the change-over valve 4 is moved up because of the differential pressure. The fuel inside the fuel inlet passage 15 flows into the servo piston chamber 16, hence forcing a servo piston 2 down together with a plunger 3. |
