In view of the foregoing issues, an object of the present invention is to provide a vehicle control device that reduces the constraints of heat generation and charging time of a booster circuit, and decreases favorably the fuel consumption and exhaust emission of an engine. A vehicle control device installed in a vehicle, the device includes: a battery; a high-voltage battery that has a voltage higher than a voltage of the battery; and a fuel injection device that injects fuel into an internal combustion engine, wherein the vehicle control device includes a control unit that determines whether to supply a drive current to the fuel injection device by the battery or supply a drive current to the fuel injection device by the high-voltage battery, and controls the fuel injection device.

A method of controlling a fuel injection device that can control a small amount of injection is provided. A fuel injection device for use in an internal combustion engine, includes: a valve body that can open and close a fuel passage, a needle that transfers a force with the valve body, and executes valve opening/closing operation, and an electromagnet that includes a coil and a magnetic core provided as a driver for driving the needle, and a cylindrical nozzle holder disposed on an outer periphery of the magnetic core and the needle, in which a current is supplied to the coil to exert a magnetic attractive force between the magnetic core and the needle to open the valve body.

A fuel injection controller includes an increase control portion applying the boost voltage to the coil to increase a coil current to a first target value, and a constant current control portion applying a voltage to the coil to hold the coil current to a second target value. A threshold is an energization time period that is necessary to reach a boundary point between a seat throttle area of a property line and an injection-port throttle area of the property line from an energization start time point. An initial-current applied time period is from the energization start time point that the boost voltage starts to be applied to the coil to a time point that the coil current is decreased to the second target value. The increase control portion controls the coil current such that the initial-current applied time period is less than the threshold.

Provided is a booster device for driving an injector which can suppress an insufficiency of a boost voltage applied to the injector even when the fuel injection interval is short. A boost driver (switching element) is connected to a boost coil in series and turns on/off the conduction of the boost coil. A boost capacitor applies a voltage to the injector. A boost diode has an anode connected to a connection point of the boost coil and the boost driver and a cathode connected to the boost capacitor. A boost gate control circuit controls the boost driver to be turned on/off so as to increase a charging speed of the boost capacitor increases when a decision period indicating a period corresponding to an injection interval of the injector is equal to or less than the first threshold value.

A method is provided for determining the point in time of a predetermined open state (e.g., start or stop time of an opening or closing process) of a fuel injector having a coil drive for an internal combustion engine of a motor vehicle. The method includes applying a first voltage pulse to the magnetic coil drive of the fuel injector, detecting a first temporal progression of the current intensity of a current flowing through the coil drive, applying a second voltage pulse to the magnetic coil drive of the fuel injector, detecting a second temporal progression of the current intensity of the current flowing through the coil drive, determining a differential progression based on the first and second temporal progressions of the current intensity, and determining a point in time at which the differential progression exhibits an extremum, which corresponds with the point in time of the predetermined open state.

A fuel injection controller includes an increase control portion applying the boost voltage to the coil to increase a coil current to a first target value, and a constant current control portion applying a voltage to the coil to hold the coil current to a second target value. A threshold is an energization time period that is necessary to reach a boundary point between a seat throttle area of a property line and an injection-port throttle area of the property line from an energization start time point. An initial-current applied time period is from the energization start time point that the boost voltage starts to be applied to the coil to a time point that the coil current is decreased to the second target value. The increase control portion controls the coil current such that the initial-current applied time period is less than the threshold.

Provided is a fuel injection control device capable of improving detection accuracy of a singular point with respect to a characteristic of the fuel injection valve to be equal to or higher than an original time resolution of the A/D conversion, and capable of accurately detecting the singular point. A variable control part 24 variably controls a conversion timing of the A/D conversion part 221 such that the conversion timing of A/D conversion for physical quantity data related to driving of the fuel injection valve 10 is relatively changed, the A/D conversion part 221 acquires a plurality of time series data by performing A/D conversion on the physical quantity data at a conversion timing before change and at a conversion timing after change by the variable control part 24, and a detection part 223 detects a singular point with respect to the characteristic of the fuel injection valve 10 based on the plurality of time series data.

A voltage limiting circuit of a solenoid drive device includes a function to limit the value of a boost voltage generated by a boost voltage power source circuit. The voltage limiting circuit is equipped with a boost voltage comparing unit and a boost voltage discharge unit. The boost voltage comparing unit compares a voltage-divided value of the boost voltage with a reference voltage value, and in the case that the voltage-divided value is higher than the reference voltage value, the boost voltage discharge unit lowers the voltage-divided value to be less than or equal to the reference voltage value.

The present disclosure relates to injection valves. The teachings thereof may be embodied in various valves, fuel injectors, and methods for controlling valves. An example method for setting operational parameters of a fuel injector may include: determining a measurement-specific maximum current value; applying a voltage pulse to the coil drive of the fuel injector; detecting a time curve of the current intensity of a current flowing through the coil drive; ending the voltage pulse when the detected current intensity reaches the maximum current value; and storing the time curve of the detected current intensity. The method may include generating a plurality of differential curves each based on two stored time curves of the detected current intensity for successive measurements; determining a peak current for driving the actuator of the fuel injector based at least in part on the plurality of differential curves; and operating the coil at the determined peak current.

A control apparatus, which controlling an operation of an injector provided to an internal combustion engine, includes: a voltage application unit applying a voltage raised to have a step-up target value to the injector to open the injector; a current measurement unit measuring a drive current supplied to the injector in response to an application of the voltage; and a calculator calculating a current difference value which indicates a difference between an actually-measured profile and a reference profile. The actually-measured profile indicates a time-variation in an actually-measured value of the drive current, and the reference profile is a profile set in advance. The step-up target value is corrected according to the current difference value that is calculated.