A drive circuit is controlled when power is interrupted. When power is turned off, a main power supply is switched to a sub-power supply, and a residual charge of a step-up circuit is lowered to a drive voltage of a drive circuit using a step-down circuit is used as the sub-power supply.

Disclosed is a method for controlling a fuel injector provided with a solenoid for actuating a needle which opens the injector and with a spring for returning the needle to the closed position. The solenoid is supplied with power by a controller including a first potential and a second potential, a first diode and a second diode, a first transistor, a second and a third transistor which is controlled so as to generate various currents using the potentials.

A drive circuit is controlled when power is interrupted. When power is turned off, a main power supply is switched to a sub-power supply, and a residual charge of a step-up circuit is lowered to a drive voltage of a drive circuit using a step-down circuit is used as the sub-power supply.

Method for controlling a fuel injector with a solenoid actuating a needle opening the injector and a spring returning the needle to the closed position. A controller, powering the solenoid, provides a first potential connected to a first transistor's drain, the source of the first transistor connected to the first diode's anode, the cathode of the first diode connected to a second diode's cathode, to a first connector of the solenoid and to the source of a second transistor. The drain of a second transistor is connected to a second potential, the second diode's anode being connected to ground, the second potential being connected to ground via a capacitance and to the cathode of a third diode, the third diode's anode being connected to a second connector of the solenoid and to the drain of a third transistor, the source of the third transistor being connected to ground.

An electromagnetic valve driving device which drives a fuel injection valve having a solenoid coil, includes: a regenerative switching element disposed between a first end portion of the solenoid coil and the ground; and a control unit configured to control the regenerative switching element to be in an ON state or an OFF state, wherein the control unit includes: a voltage detection unit configured to detect a voltage of the first end portion of the solenoid coil; and an abnormality detection unit configured to detect an abnormality of the regenerative switching element on the basis of the voltage detected by the voltage detection unit.

Method for controlling a fuel injector with a solenoid actuating a needle opening the injector and a spring returning the needle to the closed position. A controller, powering the solenoid, provides a first potential connected to a first transistor's drain, the source of the first transistor connected to the first diode's anode, the cathode of the first diode connected to a second diode's cathode, to a first connector of the solenoid and to the source of a second transistor. The drain of a second transistor is connected to a second potential, the second diode's anode being connected to ground, the second potential being connected to ground via a capacitance and to the cathode of a third diode, the third diode's anode being connected to a second connector of the solenoid and to the drain of a third transistor, the source of the third transistor being connected to ground.

Disclosed is a method for controlling a fuel injector provided with a solenoid for actuating a needle which opens the injector and with a spring for returning the needle to the closed position. The solenoid is supplied with power by a controller including a first potential and a second potential, a first diode and a second diode, a first transistor, a second and a third transistor which is controlled so as to generate various currents using the potentials.

An electromagnetic valve driving device which drives a fuel injection valve having a solenoid coil, includes: a regenerative switching element disposed between a first end portion of the solenoid coil and the ground; and a control unit configured to control the regenerative switching element to be in an ON state or an OFF state, wherein the control unit includes: a voltage detection unit configured to detect a voltage of the first end portion of the solenoid coil; and an abnormality detection unit configured to detect an abnormality of the regenerative switching element on the basis of the voltage detected by the voltage detection unit.

An internal combustion engine according to the present disclosure has an ignition coil and an injector that share a power source, and has a controller that controls energization to the ignition coil and energization to the injector. The controller executes setting processing and correction processing. In the setting processing, the controller sets an energization period of the ignition coil in accordance with an operating condition of the internal combustion engine. In the correction processing, when the energization period of the ignition coil overlaps with an energization period of the injector, the controller corrects the energization period of the ignition coil so as to reduce an overlap period between the energization period of the ignition coil and the energization period of the injector.

A switching apparatus for switching a first actuator and a second actuator between a power supply and a ground, including: a first switch for switching a first current path between the first actuator and the ground; a second switch for switching a second current path between the second actuator and the ground; and a third switch for switching a current path between the power supply and the first actuator and a current path between the power supply and the second actuator; in which, as a result of the switching, the third switch simultaneously closes or opens the current path to the first actuator and to the second actuator. Also described are a related brake system and method.