Abstract: There is provided a high-pressure fuel pump drive circuit for manipulating the electric current to be passed to a solenoid coil for controlling a high-pressure pump.

Abstract: There is provided an internal combustion engine controller that realizes a reduction in maximum current value and current regulation without sacrificing boost performance.

Abstract: A fuel injection control apparatus is capable of reducing a minimum quantity of fuel injection without reducing a maximum quantity of injection. To open a fuel injector valve, a driving circuit supplies an electric current from a high-voltage power supply to the fuel injector. Then, after valve opening, the high-voltage power supply is switched to a low-voltage power supply, and an open state of the valve is retained. For opening the valve of the fuel injector, a microcomputer, after supplying current from the high-voltage power supply to the injector, discharges the current rapidly for a decrease below a first current level at which the open state of the valve cannot be retained. The microcomputer then controls the supply current to the injector so as to supply a current at a second current level at which the open state of the valve can be retained.

Abstract: There is proposed a control unit for an internal combustion engine, which comprises a boost circuit, a switching element, a current detecting resistor and a controller and is designed to be actuated such that the boost circuit is used to boost a power source voltage to create a boosted voltage and the controller is used to control the switching element so as to enable the boosted voltage to flow to the injector solenoid coil. This control unit is designed such that, when the boost circuit goes out of order, the injector solenoid coil is excited by making use of the power source voltage without using the boosted voltage and without creating a peak current to thereby generate a first holding current required for opening the injector and a second holding current required for retaining the opened state of the injector, the second holding current being lower in intensity than the first holding current.

Abstract: A fuel injection control apparatus includes a computing unit that calculates a pulse width for a pulse signal which drives the valve of a fuel injector, based on the operational state of the internal combustion engine and fuel pressure detected by a fuel pressure sensor. After a valve-opening command has turned on and a high valve-opening current has been supplied to open the fuel injector valve, a fuel injector driving signal waveform command unit discharges the current and supplies a small hold current Ih2 to maintain the injector's valve-open state. After the elapse of a predetermined rapid-discharge starting time from the turn-on of the valve-opening command, the fuel injector driving signal waveform command unit rapidly discharges the current until the hold current Ih2 has been reached.

Abstract: In a voltage boost circuit for driving a fuel injector of an internal combustion engine, a high voltage developed in the voltage boost coil will be discharged into the battery power supply through the boost coil by electrically energizing a discharge switching element provided in parallel to the charging diode. If the overboost compensation overlaps a boost execution period, the end of the boost execution period will await starting of the overboost compensation.

Abstract: An internal combustion engine controller comprises a booster coil connected to a battery and a booster capacitor. A switch element is connected to the booster coil to control the passage of current through the booster coil and an interruption of the current. The booster capacitor accumulates electrical energy generated with an inductance of the booster coil at the time of the interruption of the passage of the current. A booster control circuit carries out control in a constant boost switching cycle so as to pass the current through the booster coil and the switch element until the current reaches a preset switching stop threshold value and then interrupt the current to charge the energy generated with the inductance of the booster coil into the booster capacitor. The booster control circuit is configured to ensure a minimum time period for the booster capacitor-charging of the energy within the boost switching cycle.

Abstract: An internal combustion engine controller has: a voltage booster circuit for boosting a battery power source; a booster side driver element for flowing a current through the injectors by using the boosted voltage; a battery side driver element disposed in parallel with the booster side driver element to flow a current through the injectors by using the battery power source; a first downstream side driver element provided by controlling currents flowing through the injectors; current regeneration diodes for flowing currents from the downstream side to the upstream side of the injectors; a booster side current detector resistor for detecting currents flowing via the current regeneration diodes; and an injector control circuit for controlling and driving the booster side driver element, battery side driver element and first downstream side driver element.

Abstract: In a voltage boost circuit for driving a fuel injector of an internal combustion engine, a high voltage developed in the voltage boost coil will be discharged into the battery power supply through the boost coil by electrically energizing a discharge switching element provided in parallel to the charging diode. If the overboost compensation overlaps a boost execution period, the end of the boost execution period will await starting of the overboost compensation.

Abstract: An internal combustion engine controller that drives an electromagnetic load is provided for improving a fault diagnosis precision of the electromagnetic load and stabilizing a high-speed control without influence of noises even if the drive cycle of the electromagnetic load is short. The internal combustion engine controller has high reliability in a fault diagnosis for a circuit to regenerate counter electromotive energy. The internal combustion engine controller comprises a current source or a voltage source for controlling a potential of the diagnosis position in order to ensure a high-precision fault diagnosis even if the drive cycle of the electromagnetic load, such as the fuel injector, in the internal combustion engine is shortened. Diagnosis timing is optimally set or the number of determinations for averaging is increased in order to ensure the high-precision fault diagnosis without being influenced by unexpected disturbance such as noises.

Abstract: Disclosed herein is a fuel injection control apparatus for an internal combustion engine, capable of opening and closing accurately a valve of the fuel injector even when the quantity of injection required is small and a pulse duration of a driving pulse signal to the fuel injector is short. A fuel injector pulse width computing unit 9a calculates, from the operational state of the internal combustion engine and the fuel pressure detected by a fuel pressure sensor, pulse width of a pulse signal which drives the valve of the fuel injector. After an valve-opening command has turned on and a high valve-opening current for opening the fuel injector valve has been supplied from a high-voltage source to the fuel injector, a fuel injector driving signal waveform command unit 9b discharges the current and supplies from a low-voltage source a small hold current Ih2 that allows the fuel injector to maintain the valve-open state.

Abstract: To provide a fuel injection control apparatus capable of reducing the minimum quantity of fuel injection without reducing the maximum quantity of injection. For fuel injector valve opening, a driving circuit 56 supplies an electric current from a high-voltage power supply VH to the fuel injector 53, then after valve opening, switches the high-voltage power supply VH to a low-voltage power supply LV, and retains the open state of the valve. A microcomputer 57 is adapted such that for opening the valve of the fuel injector, the microcomputer, after supplying the current from the high-voltage power supply to the injector 53, discharges the current rapidly for a decrease below a first current level Ihold1 at which the open state of the valve cannot be retained, and then controls the supply current to the injector 53 so as to supply a current of a second current level Ihold2 at which the open state of the valve can be retained.

Abstract: A control device 10 for an internal combustion engine 80 includes an injector drive circuit 90 that drives an injector 30 that injects fuel and a temperature detection device that at least detects timing when a temperature condition that the temperature of the injector drive circuit 90 exceeds predetermined temperature is satisfied. The control device 10 includes a heat-generation-suppression control means 104 that performs control for suppressing the heat generation of the injector drive circuit 90. The heat-generation-suppression control means 104 selects, on the basis of a driving state of a vehicle, at least one parameter among an electric current applied to the injector, fuel pressure supplied to the injector 30, the number of revolutions of the internal combustion engine, and voltage from a battery to be boosted and performs control for limiting a value of the selected parameter on the basis of the timing.

Abstract: An electronic circuit device comprises: a printed circuit board mounted with electronic components; a resin-molded portion formed of resin so disposed that the electronic components are covered therewith; a convex connector that has metal terminals for connection and is exposed from the resin-molded portion; and a sealing member wrapped around the resin-molded portion.

Abstract: There is proposed a control unit for an internal combustion engine, which comprises a boost circuit, a switching element, a current detecting resistor and a controller and is designed to be actuated such that the boost circuit is used to boost a power source voltage to create a boosted voltage and the controller is used to control the switching element so as to enable the boosted voltage to flow to the injector solenoid coil. This control unit is designed such that, when the boost circuit goes out of order, the injector solenoid coil is excited by making use of the power source voltage without using the boosted voltage and without creating a peak current to thereby generate a first holding current required for opening the injector and a second holding current required for retaining the opened state of the injector, the second holding current being lower in intensity than the first holding current.

Abstract: An electronic circuit device comprises: a printed circuit board mounted with electronic components; a resin-molded portion formed of resin so disposed that the electronic components are covered therewith; a convex connector that has metal terminals for connection and is exposed from the resin-molded portion; and a sealing member wrapped around the resin-molded portion.

Abstract: According to the present invention, the operation of a diagnostic circuit within a load drive circuit, which has been built into an electronic control device, is checked without modifying the electronic control device or the like. The load drive circuit, which drives a load such as a solenoid using a DC power supply as a power supply, includes a drive circuit and a diagnostic circuit which is independently provided within the drive circuit. Upon input of a drive-stop signal from a control circuit that controls the drive circuit, the operation of at least the drive circuit stops, so that whether the diagnostic circuit, which diagnoses the condition of the load, is normally operating or not is checked in a condition in which the load drive circuit has been built into the electronic control device.

Abstract: An internal combustion engine controller has: a voltage booster circuit for boosting a battery power source; a booster side driver element for flowing a current through the injectors by using the boosted voltage; a battery side driver element disposed in parallel with the booster side driver element to flow a current through the injectors by using the battery power source; a first downstream side driver element provided by controlling currents flowing through the injectors; current regeneration diodes for flowing currents from the downstream side to the upstream side of the injectors; a booster side current detector resistor for detecting currents flowing via the current regeneration diodes; and an injector control circuit for controlling and driving the booster side driver element, battery side driver element and first downstream side driver element.

Abstract: In resin-molded engine control unit, a coil, an electrolytic capacitor, a microprocessor, electronic parts and a connector terminal are mounted on a board. Inside a cover fixed on the board, a resin-free region is formed. The coil, the electrolytic capacitor and the microprocessor, which should not be sealed with resin, are mounted in the resin-free region, while the board and the electronic parts which are not capped by the cover are sealed with a resin.

Abstract: A module comprises a metallic terminal pins for connection and a circuit board with electronic components mounted thereon, a circuit board connecting side of the connector. The electronic components and the circuit board with the electronic components mounted thereon are encapsulated with the same resin. A metallic base is united to the module to obtain an electric conduction between the metallic base and the circuit board.