A drive circuit for operating a solenoid includes a main switch and a charge pump circuit. The main switch is coupled in series with a coil of the solenoid. The main switch is configured to selectively enable current flow from a voltage source according to a main switching signal to translate a poppet of the solenoid between an opened position and a closed position. The charge pump circuit is coupled to the voltage source. The charge pump circuit is configured to discharge through the coil to translate the poppet from the closed position to the opened position, and to charge when the poppet is held in the opened position.

A drive circuit anomaly diagnosing device of the present invention performs an anomaly diagnosis on a drive circuit including a power supply line on which a solenoid is disposed midway, a main switch disposed on the power source side relative to the solenoid, a first diode disposed on a protection line connecting a point between the main switch and the solenoid to ground with a forward direction corresponding to a direction from the ground side to the power source side, and a first capacitor interposed on a first line connecting a point between the protection line and the solenoid to the ground midway on the power supply line, the drive circuit being configured to supply power to the solenoid, on the basis of a current detected by a first current sensor disposed upstream of the main switch on the power supply line.

An operation coil drive device includes a drive control unit to perform control to set, for a semiconductor switching element to switch on and off the source voltage applied to an operation coil of a magnetic contactor, a larger ON/OFF time ratio for a circuit-closing control and a smaller ON/OFF time ratio for a holding control, wherein the drive control unit includes: a circuit-closing-control inductance calculation unit to calculate an inductance of the operation coil immediately after a start of the circuit-closing control; a circuit-closing-control resistance value calculation unit to calculate a direct current resistance value of the operation coil based on the calculation result; and a circuit-closing-control switching correction unit to correct the ON/OFF time ratio of the semiconductor switching element for the circuit-closing control based on the calculation result.

Device forming an electromagnetic lock comprising an electromagnetic suction pad (3) comprising an electromagnet (4), a counter plate (1) and an electric circuit comprising a current source designed to supply at least one coil of the electromagnet of the electromagnetic suction pad with an electric magnetization current to create an electromagnetic field and an associated electromagnetic force pinning the counter plate and the electromagnetic suction pad against one another to close the lock; switching means designed to cut off the supply of current; and anti-remanent means for dealing with the remanent electromagnetic force which remains when the switching means have disconnected the supply of current to the electromagnetic coil.

A load drive device that drives and controls an inductive load based on a PWM signal from a microcomputer is provided, and the load drive device has excellent reliability and responsiveness capable of quickly detecting disconnection of the inductive load. The load drive device includes a microcomputer and a driver circuit that drives an inductive load by a pulse width modulation signal of a constant cycle based on a control command from the microcomputer, in which the driver circuit includes a current monitoring circuit that monitors a current flowing through the inductive load, and a disconnection diagnosis circuit that detects disconnection of the inductive load based on a current value detected by the current monitoring circuit, and the disconnection diagnosis circuit obtains a change amount of a current value detected by the current monitoring circuit, and when the change amount is equal to or less than a predetermined threshold, determines that the inductive load is disconnected and notifies the microcomputer of the disconnection.

The disclosure proposes a method for controlling discharge of a solenoid valve arranged in a vehicle, wherein the solenoid valve comprises an inductor and a plunger arranged to be moved by the inductor from a hold position to a rest position, whereby the solenoid valve is opened or closed. The method comprises stepwise discharging the inductor by discharging the inductor at a slow decay rate during an operating time period during which a final part of a movement of the plunger from the hold position to the rest position takes place. The method further comprises discharging the inductor at a fast decay rate during at least one other time period, wherein the plunger is stagnant during at least a part of said other time period, wherein the fast decay rate is faster than the slow decay rate.

A fast shut-off solenoid circuit network includes a solenoid circuit and a current dissipation circuit. The solenoid circuit is operable in response to an electrical current, and configured to operate in an enable mode and a disable mode. The current dissipation circuit is configured to dissipate the current discharged from the solenoid circuit in response to invoking the disable mode. The fast shut-off solenoid circuit network further includes a dissipation bypass circuit. The dissipation bypass circuit is configured to divert the current discharged by the solenoid circuit away from current dissipation circuit when operating in the enable mode.

A solenoid for a motor vehicle starter includes at least one coil wound on at least one spool, the at least one coil defines a toroidal space encircling the at least one coil. A stop member is positioned adjacent to the at least one spool. A diode holder is positioned in the toroidal space defined by the at least one coil, and a diode is positioned in the diode holder. The diode includes a cylindrical body, a first lead extending from a first end of the cylindrical body, and a second lead extending from a second end of the cylindrical body. The cylindrical body of the diode is retained by the diode holder within the toroidal space, and the first lead of the diode extends out of the toroidal space and is electrically connected to the stop member.

An electromagnetic relay includes a fixed contact, a moving contact, an electromagnet device, and a second coil. The moving contact moves from a closed position where the moving contact is in contact with the fixed contact to an open position where the moving contact is out of contact with the fixed contact, and vice versa. The electromagnet device includes a first coil and a mover. The mover is actuated on receiving a magnetic flux generated when a current flows through the first coil to move the moving contact from one of the closed position or the open position to the other position. The second coil gives, when a current flows through the second coil, at least a magnetic flux, of which a direction is opposite from a direction of the magnetic flux generated by the first coil, to the mover.

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.