| 摘要 |
PROBLEM TO BE SOLVED: To stably maintain a valve element lift amount at a first lift amount in a fuel injection control device in which the rising speed of a needle valve is changed in two steps by changing the valve element lift amount of a control valve for controlling the rear surface pressure of the needle valve from the first lift amount to a second lift amount (> first lift amount). SOLUTION: When the drive force of an actuator 43b reaches a first drive force, the lift amount of a valve element 43a is changed to the first lift amount, and the valve element 43a starts to come into contact with a piston 43c at the initial position. When the drive force is equal to or less than a second drive force (> first drive force), the piston 43c is not allowed to move from the initial position by the pressing of the valve element 43a, and the valve element lift amount is maintained at the first lift amount. When the drive force is above a third drive force (> second drive force), the piston 43c is moved to a first position by the pressing of the valve element 43c, and the valve element lift amount is changed to the second lift amount. A flow passage allowing a fuel to flow from a fuel supply passage C1 into a control chamber R2 is opened when the piston 43c is at the initial position, and cut off when it is at the first position. COPYRIGHT: (C)2008,JPO&INPIT
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