| 摘要 |
PROBLEM TO BE SOLVED: To ensure both stability of control and responsiveness of control, in a fuel injection device to control a discharge state of fuel from a fuel injection pump by metering a fuel amount sucked in the fuel injection pump. SOLUTION: In this accumulator type fuel injection device, the opening area of a metering valve located in a suction passage for fuel to a fuel injection pump is controlled through duty control of a solenoid current so that a pressure in a common rail to store discharge fuel from the fuel injection pump is controlled to a target pressure. In this case, during steady operation, by a control frequency set by attaching importance to stability of control, duty control of a solenoid current is executed and from a change amount of a target common rail pressure being a control target, a transient time of control is decided. Thereafter, the control frequency is varied to a low frequency lower than that during steady operation for a fixed time in which a common rail pressure reaches a target pressure. This constitution improves responsiveness of control since movement of a valve element itself is quickened though behavior of the valve element of the metering valve is rendered unstable.
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