A fuel injection valve includes: a movable arrangement that is coupled to a movable core and a needle while a movable flow passage, which forms a part of a flow passage of the fuel injection valve, is formed at an inside of the movable arrangement; and a valve main body that receives the movable arrangement. The movable arrangement has: a first flow-restricting portion that reduces a cross-sectional area of a portion of the movable flow passage; and a second flow-restricting portion that is spaced away from the first flow-restricting portion and reduces a cross-sectional area of another portion of the movable flow passage to a cross-sectional area that is equal to or larger than a cross-sectional area of the first flow-restricting portion. A distance between the first flow-restricting portion and the second flow-restricting portion is larger than an equivalent diameter of the cross-sectional area of the second flow-restricting portion.

A fuel injection control method of injecting fuel to a combustion chamber through an injector, the method may include performing, by a controller electrically-connected to the injector, a main injection configured of controlling the injector to inject the fuel in a target injection fuel amount; and performing, by the controller, a pre-injection configured of driving the injector to inject the fuel in advance, before the performing of the main injection with a predetermined idle time interposed therebetween, wherein the performing of the pre-injection is configured of magnetizing an injector coil of the injector by applying a current to the injector during a predetermined pre-injection time, in which a flow rate of the fuel is prevented from being generated by the pre-injection.

An energization instruction switch switches energization instruction signals to instruct energization of fuel injection valves. A first cylinder designation switch designates one of the energization instruction signals to designate a valve closing detection cylinder. A valve closing detection unit monitors downstream voltage of the fuel injection valve to detect occurrence of an inflection point in change of the downstream voltage to detect a valve closing. A second cylinder designation switch designates one of the downstream voltages and designates the valve closing detection cylinder. A valve closing time measuring unit measures a valve closing time, which is from a switching timing of the energization instruction signal from ON to OFF to a valve closing detection timing, for injection of the valve closing detection cylinder. A valve closing time learning unit learns the valve closing time measured by the valve closing time measuring unit.

A method for controlling the electrical power supply of injectors for a hybrid automotive vehicle, including an internal combustion engine and an electric motor. A first electrical network, having a first DC voltage, supplies power to a motor control of the engine. A second electrical network having a second DC voltage, higher than the first DC voltage, supplies power to the electric motor. The method includes connecting the second DC voltage to the injectors; reading the value of the second DC voltage; adapting control parameters of the injectors based on the value of engine speed, engine temperature and injection pressure upstream of the injectors; and controlling the injectors using the second DC voltage. Wherein there is no change in the control parameters when the value is higher than a threshold value; and changing at least one of the control parameters when the value is lower than the threshold value.

The present invention provides a high-efficiency and highly-reliable fuel injection control device that controls a fuel injection valve of an internal combustion engine and can perform injection amount control in accordance with a deterioration degree of the fuel injection valve. A fuel injection control device controlling a fuel injection valve of an internal combustion engine includes a deterioration determination unit that determines a deterioration state of the fuel injection valve, an injection amount learning unit that learns the injection amount of the fuel injection valve, and a learning frequency change unit that changes the learning frequency of the injection amount learning unit in accordance with the deterioration state of the fuel injection valve.

An electromagnetic valve drive device includes: a state detection unit configured to detect an on-state or an off-state of a first switch and a second switch forming a boosting circuit; a boosting control unit configured to control a boosting operation, by performing a synchronous rectification control on switching of the first switch and the second switch, depending on the state of the first switch or the second switch detected by the state detection unit; and a drive circuit configured to drive an electromagnetic valve by supplying a voltage boosted by the boosting operation to the electromagnetic valve.

A fuel injection control device includes an injection valve drive circuit that drives a plurality of injection valves, a booster circuit that generates a boosted voltage supplied to the injection valve drive circuit; and a fuel pump drive circuit that drives a fuel pump for compressing fuel of an internal combustion engine. The fuel pump drive circuit is configured to, when driving the fuel pump, regenerate energy into the booster circuit. The injection valve drive circuit is configured to, during a non-drive period of the injection valves or during a period in which the fuel pump is intermittently driven continuously, perform a non-valve opening energization on at least one of the plurality of injection valves.

Various embodiments include a method for operating a fuel injector comprising: applying a first current to a solenoid to perform a first injection process and inject a predefined injection quantity; determining a value of a system parameter indicating the relationship between the actual fuel quantity and the predefined quantity; determining, on the basis of the value of the system parameter, whether the actually injected fuel quantity is smaller than the predefined fuel quantity by a predefined amount corresponding to a disparity between a magnetic force exerted on the armature in the direction of the pole piece and an opposite hydraulic force exerted on the armature by fuel; and if it was determined that the quantities differ by enough, applying a second current to the solenoid to perform a second injection; wherein the second current exerts a lower magnetic force on the armature in the direction of the pole piece.

Disclosed is a method for regulating the duty cycle of a controlled current signal of a conversion module of a voltage converter including a step of measuring, by the microcontroller, the duty cycle of the envelope of the controlled current signal, and when the value of the duty cycle is below a predetermined threshold, a step of controlling, by the microcontroller, the current control module to decrease the amplitude of the control signal and that the duty cycle of the envelope of the controlled current signal thus tends toward a predetermined threshold, or when the value of the duty cycle is higher than the predetermined threshold, a step of controlling, by the microcontroller, the current control module so the current control module increases the amplitude of the controlled current signal and that the duty cycle of the envelope of the controlled current signal thus tends toward the predetermined threshold.

Various embodiments may include a method for actuating a fuel injector with a solenoid drive and a nozzle needle. The solenoid drive has a solenoid and a movable armature. The fuel injector has an idle stroke between the armature and the nozzle needle. An example method includes: applying a precharging current to the solenoid drive during a precharging phase to move the movable armature into mechanical contact with the nozzle needle; and applying a voltage pulse to the solenoid drive during a boost phase until the current intensity of the current flowing through the solenoid reaches a predetermined peak value.