The present invention determines whether multi-stage injection control is operating normally or abnormally, and carries out a failsafe of multi-stage injection control as necessary. The present invention, which solves the problem described above, has means such as the following. The invention is provided with fuel injection valves provided respectively to each cylinder, an opened/closed valve detection means for detecting either one or both of an open valve state and a closed valve state of the fuel injection valves on the basis of the drive currents or drive voltages of the fuel injection valves, and a detection execution determination means for determining a detection execution time period including the detection start timing and the detection end timing of the open valve state or closed valve state; detection interference such as overlapping detection with another cylinder and overlapping of open valve detection and closed valve detection being preventable, and risks such as erroneous detection being reducible.

Provided is an injector control unit capable of preventing unintended fuel injection other than an engine drive period. The injector control unit includes a cutoff mechanism for cutting off current supply to the injector from at least the ignition OFF to the next ignition ON.

A control device controls a drive current that flows through a drive coil of a fuel injection valve that is electromagnetically driven. A control device includes a determination unit configured to determine whether a supply fuel pressure, which is a pressure of fuel supplied to the fuel injection valve, is higher than a determination pressure at which the fuel pressure is determined abnormally high; a first control unit configured to control the drive current in a first mode when the determination unit determines that the supply fuel pressure is not higher than the determination pressure; and a second control unit configured to control the drive current in a second mode that facilitates maintaining of the fuel injection valve in an open state more than in the first mode when the determination unit determines that the supply fuel pressure is higher than the determination pressure.

Controlling a fuel injector in a fuel system for an engine includes switching between a boosted voltage power supply and a lower voltage power supply during energizing a solenoid actuator in a fuel injector, and generating a solenoid energizing waveform including a pull-in tier produced by a boosted voltage incipient current, a boosted voltage second current, and a lower voltage later current, based on the switching between a boosted voltage power supply and a lower voltage power supply. Controlling a fuel injector further includes detecting an arrival timing of the valve based on a property of the lower voltage later current, and electronically trimming the fuel injector based on the detecting an arrival timing. Related control system logic is also disclosed.

A fuel injection control device which is provided with an input terminal to which a first pulse signal for driving a liquid fuel injection valve is input and an output terminal from which the first pulse signal is output, and converts the first pulse signal which is input from the input terminal to a second pulse signal for driving a gaseous fuel injection valve, includes: a P-channel field-effect transistor interposed in a wiring which connects the input terminal and the output terminal; a switching control section which performs switching control between an ON state and an OFF state of the field-effect transistor; and a gate drive circuit which maintains the field-effect transistor in the ON state in a case where power supply to the switching control section is not performed.

An injection control device includes: a conversion coefficient setter setting a conversion coefficient for each injection when a fuel injection valve is driven by an electric current to inject fuel from the fuel injection valve; and an area correction unit calculating an energization time correction amount by performing area correction using the conversion coefficient for each injection regardless of whether a drive current of the fuel injection valve has reached a target peak current or not.

An injection control device of capable of correcting an energization time even in an S/N non-guaranteeable situation includes: an energization controller calculating an energization time correction amount based on an area correction performed by an energization time correction amount calculator regarding electric current flowing in a fuel injection valve when the fuel injection valve is electrically driven for injecting fuel; and an energization instruction time calculator correcting an energization instruction time for fuel injection in a next cycle and thereafter by using the energization instruction time correction amounts in or before a current cycle.

Appropriate detection of an abnormality of voltage information, which is a basis for correcting a fuel injection amount, becomes possible. For this reason, a fuel injection control device 127, which has a drive IC 208 controlling a fuel injection drive unit 207a to supply a high voltage to a solenoid 405 so as to open a fuel injection valve 105 and controlling the fuel injection drive unit 207a to supply a low voltage to the solenoid 405 so as to hold a valve-open state of the fuel injection valve 105, includes: a drive voltage input unit 211 that measures and outputs voltage information based on an upstream voltage of the solenoid 405 of the fuel injection valve 105 and a downstream voltage of the solenoid 405; a fuel injection amount correction unit 213 that corrects a fuel injection amount of the fuel injection valve 105 based on the voltage information output from the drive voltage input unit 211; and a voltage input function abnormality detection unit 212 that detects whether an output of the drive voltage input unit 211 is abnormal based on the voltage information output from the drive voltage input unit 211.

An injection control device controls the opening and closing of a fuel injection valve by performing peak current drive and constant current drive and controls injection of fuel from the fuel injection valve to an internal combustion engine. The injection control device includes a preheat current energization control unit configured to, when a temperature of a solenoid coil of the fuel injection valve prior to starting the internal combustion engine is lower than a predetermined temperature, energize the fuel injection valve with a preheat current having an output density that causes the temperature of the solenoid coil to increase, the preheat current being within a range that maintains the fuel injection valve in a valve closed state, and when the temperature of the solenoid valve increases to or above the predetermined temperature, stop the energization of the fuel injection valve with the preheat current.

An injection control device includes: a fuel injection quantity command value output unit that outputs a command value for a fuel injection quantity of a fuel injection valve; and a controller that executes current control on the fuel injection valve. The controller executes current area correction by calculating an area correction amount for an energization time to cause an integrated current value of an energization current profile and the integrated current value of a current to be equal to each other. Correction control of the current area correction is changed based on a detection signal of a cooling water temperature of an internal combustion engine.