An object of the present invention is to promote the stabilization of the fuel injection amount in a fuel injection device in which a valve body and a movable iron core are configured to be relatively displaceable. In a control unit 120 of a fuel injection device 100 which includes a control part that controls the energization time of a current flowing through a coil 108 based on the pulse width of a drive command pulse, the control part is configured to be able to execute control to split a required fuel injection amount for one combustion cycle into portions and inject the portions in a plurality of times. In addition, in injections including a sequence of a preceding drive command pulse Pi1 and a subsequent drive command pulse Pi2, the control part acquires a preceding drive command pulse width Ti1 of the preceding drive command pulse Pi1 and a pulse interval Tint that is the time between the end time te1 of the preceding drive command pulse Pi1 and the start time ts2 of the subsequent drive command pulse Pi2, and corrects the subsequent drive command pulse width Ti2 of the subsequent drive command pulse Pi2 by using the preceding drive command pulse width Ti1 and the pulse interval Tint.

An injector for injecting fuel including an injector housing, a movable nozzle needle with a nozzle needle tip arranged in the injector housing, and a nozzle needle seat for receiving the nozzle needle tip. A contact pairing of the nozzle needle and the nozzle needle seat here represents a mechanical switch that adopts a closed state upon contact of the nozzle needle tip with the nozzle needle seat and an open state upon interruption of the contact. Provision is additionally made that the injector has an input line and an output line for controlling movement of the nozzle needle, the switch has a first connector connected to the input line and a second connector connected to the injector housing, and a resistor connected between the first connector of the switch and the input line.

A shot variation in injection quantity of a fuel injection device is reduced. A control device according to an aspect of the present invention performs a first current control for a solenoid by a first current waveform by applying a reverse voltage to the solenoid before a mover or a valve collides with a fixed portion, when an injection quantity of a fuel from opening to closing of the valve of the fuel injection device is a set value or more. In addition, the control device performs a second current control for the solenoid by a second current waveform so that a current larger than a holding current holding the mover or the valve in a state of being in contact with the fixed portion flows to the solenoid, until the mover or the valve collides with the fixed portion, when the injection quantity of the fuel from opening to closing of the valve is less than the set value.

Provided is a fuel injection control device capable of detecting individual differences in fuel injection valves and appropriately collecting information on the individual differences. For this reason, the fuel injection control device includes a fuel injection valve drive circuit that supplies a current or a voltage to a coil of a fuel injection valve to drive the fuel injection valve, a valve body operation time period detection unit that detects a valve body operation time period related to an operation of a valve body of the fuel injection valve, and a state determination unit that determines that at least one of the fuel injection valve, the valve body operation time period detection unit, and the fuel injection valve drive circuit is abnormal based on information related to a valve body operation time period detected by the valve body operation time period detection unit.

An actuator is energized to cause a valve body of a fuel injection valve to perform fuel injection. The actuator includes a driving body to drive to open and close the valve body. Boundary energization is performed that ends energization of the actuator at a timing when the driving body is moved in an opening direction of the valve body and is assumed to have reached an end of its movement range to measure a relationship between the energization time until the energization ends and the fuel injection amount. A correspondence relationship between the energization time of the actuator and the fuel injection amount is determined by using the measured relationship. An energization time corresponding to a target injection amount is obtained with reference to the determined correspondence relationship. The actuator is energized to cause the fuel injection valve to perform fuel injection.

An injection control device includes an injector and a detection unit. The injector includes: an injection hole; a movable part; a seat portion; a valve housing; a magnetic field application unit; and a detection sensor. The movable part opens and closes the injection hole by reciprocal movement. The seat portion when seated by the movable part closes the injection hole, and when the movable part lifted therefrom opens the injection hole. The valve housing accommodates the movable part in a reciprocally movable manner. The magnetic field application unit is installed on an outer circumference of the valve housing and applies a magnetic field to the movable part and the valve housing. The detection sensor outputs a detection signal according to a size of a distance between the valve housing and the movable part.

An object of the present invention is to promote the stabilization of the fuel injection amount in a fuel injection device in which a valve body and a movable iron core are configured to be relatively displaceable. In a control unit 120 of a fuel injection device 100 which includes a control part that controls the energization time of a current flowing through a coil 108 based on the pulse width of a drive command pulse, the control part is configured to be able to execute control to split a required fuel injection amount for one combustion cycle into portions and inject the portions in a plurality of times. In addition, in injections including a sequence of a preceding drive command pulse Pi1 and a subsequent drive command pulse Pi2, the control part acquires a preceding drive command pulse width Ti1 of the preceding drive command pulse Pi1 and a pulse interval Tint that is the time between the end time te1 of the preceding drive command pulse Pi1 and the start time ts2 of the subsequent drive command pulse Pi2, and corrects the subsequent drive command pulse width Ti2 of the subsequent drive command pulse Pi2 by using the preceding drive command pulse width Ti1 and the pulse interval Tint.

A method is provided for controlling a solenoid actuated fuel injector having a solenoid actuator which moves a pintle and needle arrangement such that the needle moves away from a valve seat to an open position and also includes circuitry which applies chopped hysteresis control subsequent to an energisation phase. The method includes a) obtaining a signal of the current or voltage across the solenoid; b) analyzing the voltage or current to detect a chopped hysteresis pulse; c) determining the time point of the end of said chopped hysteresis pulse; and d) applying a braking pulse to the solenoid, the timing of which is dependent on the results of step c).

Methods and systems are provided for estimating a temperature of a direct injector. In one example, a method may include estimating the temperature of the direct injector based on a resistance of a solenoid coil of the direct injector. In one example, a pulse-width of the direct injector during an opening phase is adjusted in response to the temperature.

A method for identifying a fuel injector characteristic may include generating a signal to supply electrical current to the fuel injector, and monitoring the electrical current supplied to the fuel injector. The method may also include identifying the characteristic of the fuel injector based on the electrical current, the characteristic including a type of fuel injector, and performing a corrective action based on the type of fuel injector which was identified based on the electrical current.