| 主权项 |
1. A fuel injection controller applied to a fuel injector which opens a valve body by electromagnetic attracting force generated by applying a coil current to a coil, the fuel injection controller comprising:
a current-increase control portion applying a voltage to the coil so that the coil current is increased to a first target value; a current-hold control portion applying the voltage to the coil so that the increased coil current is held at the first target value; a battery hold control portion performs a battery hold control in which the coil current is held at a second target value lower than the first target value after a control by the current-hold control portion, and a booster circuit which boosts a battery voltage; wherein: in a case that a maximum electromagnetic attracting force to start a valve opening is referred to as a required valve-opening force, and a saturated electromagnetic attracting force by the coil current of the first target value is referred to as a static attracting force, the first target value is established in such a manner that the static attracting force is greater than or equal to the required valve opening force, the current-increase control portion and the current-hold control portion control a voltage application to the coil so that the valve body starts opening while the coil current is held at the first target value, the current-increase control portion and the current-hold control portion apply a boost voltage to the coil, and the battery hold control portion starts performing the battery hold control before a lift amount of the valve becomes a maximum value. |
