An injection control device includes: an arithmetic unit that obtains a valve-closing time for stopping injection of fuel from a fuel injection valve based on a degree of variation in a time change of a voltage generated when the fuel injection valve is driven based on a required injection amount; an injection amount change unit that increases or decreases the required injection amount; and a learning unit that repeats injection control of the fuel to learn the valve-closing time obtained by the arithmetic unit.

An injection control device includes: a booster circuit that boosts a battery voltage; a boosting control unit that performs boosting control on the booster circuit; a charge control setting unit that sets a charge prohibition time of the booster circuit for the boosting control unit; and a maximum time specification unit that specifies a maximum valve-closing detection time based on a valve-closing detection time.

An injection control device opens and closes a fuel injection valve by driving the fuel injection valve with a current to control fuel injection to an internal combustion engine. The injection control device includes: a booster circuit that boosts a battery voltage; a boosting control unit that performs boosting control on the booster circuit; and a charge control setting unit that sets charge permission or charge prohibition for the booster circuit to the boosting control unit.

A method for controlling a fuel injector of an engine system includes applying a pull-in current to close a spill valve of the fuel injector and detecting a timing at which the spill valve closes. The method also includes adjusting at least one of an amplitude of the pull-in current, a duration of the pull-in current, or a timing of a start of an application of the pull-in current based on the detected timing of the closing of the spill valve.

Various embodiments of the teachings herein include a method for controlling a cam using an ECU (electronic control unit) comprising: learning a holding region in which linearity is not ensured by increasing or decreasing a PWM signal while the cam maintains a holding state; based on the results of the learning, generating a final PWM signal; and transmitting the final PWM signal to an oil control valve. The final PWM signal comprises a sum of a minimum PWM signal for the cam to leave the holding region and a control PWM signal for the cam to reach a desired position.

An object of the present invention is to provide a control device of an injector capable of suppressing the influence of pressure reduction boiling even if pressure in a combustion chamber is low. In a case where the temperature of fuel injected from a fuel injection valve is within a set high temperature region and the pressure of the combustion chamber is within a set low pressure region, the control device of an in-cylinder direct injection-type injector according to the present invention controls to increase a lift amount of the injector as compared to the case of a low temperature region or a high pressure region.

Various embodiments include methods for operating a high-pressure pump comprising: driving a piston arranged in a compression chamber with a motor shaft; during movement of the piston toward the top dead center, closing the inlet valve so the fluid is then delivered by the piston through an outlet valve; applying a coil current to an electromagnet used to close the inlet valve during and/or after overshooting the top dead center; detecting a start time at which the coil current, on account of starting of an opening movement of the inlet valve, fulfills a predetermined change criterion; labelling a dead center rotation position of the motor shaft at which the piston is at the top dead center based at least in part on the ascertained start time; and adjusting operation of the pump based on the identified dead center rotation position.

The invention relates to a device for sensing the state of an injector, comprising an injector for injecting fuel into an engine combustion chamber, a switch, which is designed to change the switching state thereof in accordance with the state of the injector, and an evaluating unit for sensing the switching state of the switch, wherein a first switch contact of the switch is connected to an electrical input line of the injector, a second switch contact of the switch is connected to ground, and the evaluating unit is designed to carry out a first current measurement for a current flowing into the injector and into the switch and a second current measurement for the current flowing into the injector.

A method of determining the nature of a fault in the operation of a hydraulic fuel injector includes sending an actuation pulse to an actuator of the injector, the actuation pulse being above the minimum drive pulse of the injector. The method also includes analyzing a signal from an accelerometer of the injector to determine if there is a high frequency vibration component subsequent to the end of the activation pulse. The method also includes determining the functionality of a needle control valve of the injector dependent on the outcome of analyzing the signal from the accelerometer.

Various embodiments include a method for checking a calibration of a pressure sensor comprising: moving a piston toward a TDC in successive cycles; while the piston moves toward TDC, closing an inlet valve thereby adjusting a setpoint value of a fluid pressure; measuring the fluid pressure with the pressure sensor arranged downstream of the outlet valve; applying a measurement current to the electromagnet when the inlet valve is closed; while the piston moves away from TDC, detecting an opening position of the inlet valve on the basis of a predetermined change with respect to time of the measurement current at which an opening movement of the inlet valve begins; over multiple pump cycles, changing the setpoint value of the fluid pressure by a predetermined difference; checking whether the change in opening position satisfies a predetermined correspondence criterion; and if the criterion is met, generating a fault signal.