PURPOSE: To miniaturize a solenoid valve and reduce power consumption while improve durability by making the solenoid valve act as a pilot valve for opening a back pressure chamber to open a plunger chamber via a spill valve at the time of stopping fuel injection.
CONSTITUTION: As an exciting current to a solenoid valve 26 is cut off at a timing in line with an engine operating condition by a control circuit, a valve body 33 is moved to an open position by means of a spring 34 to open a second return passage 25. At this time, since a back pressure chamber 22 is disconnected from a plunger chamber 12 because of a pressure opening/closing valve 28, the pressure in the back pressure chamber 22 is suddenly reduced and a spill valve 19 is pressed by the pressure of the plunger chamber 12 and opened at a stroke against a spring 24, causing fuel to flow into a feed pump chamber 5 side out of the plunger chamber 12 to stop fuel injection. Thus, at the time of stopping fuel injection, the pressure in the plunger chamber 12 can be suddenly reduced by opening the spill valve 19 through the solenoid valve 26, enabling the momentary stoppage of fuel injection from an injection valve into an engine combustion chamber.
| JPS6030446 | [Title of the device] Boost compensator |
SAEGUSA SHOGO
AIYOSHIZAWA EIJI
