A method for end position detection in an electromagnetic, bistable actuator (101) includes applying excitation energy to the actuator (101) with the aid of a two-position controller while an armature (103) of the actuator (101) is in an end position, and determining at least one value of a switching frequency of the two-position controller.

A method and a device determine a movement profile of a solenoid plunger in a solenoid for monitoring a plunger-type armature movement for changes. The solenoid is an electromagnet in which a magnetic field can be generated by an electrical coil and a measuring unit is connected to the electrical coil. The method includes measuring a current profile with respect to time when the solenoid is operated, examining a measured current profile with respect to time for a position of a first reversal point in respect of time after operation of the solenoid and a current intensity, and assigning the position of the first reversal point to a movement end of the plunger-type armature.

The semiconductor device controls the first circuit for supplying/stopping the current supplied by a DC power supply to the latching solenoid consisting of a coil and a movable iron core and a permanent magnet, the current is measured based on the input from the current detection circuit. The semiconductor device includes a control circuit having a low power dissipation mode in which the leakage current is reduced, and a normal operation mode. The control circuit maintains the low power consumption mode when no current is flowing through the coil, when a current is flowing through the coil maintains the normal operation mode, further, the movable iron core It comprises a control circuit configured to detect the inflection point of the current detected by the current detection circuit when leaving the permanent magnet.

A method for closing an actuator in a magnetically actuated switch assembly, where the actuator includes an armature and a winding, and the switch assembly includes a manual actuation device coupled to one end of the armature and a movable terminal in a vacuum interrupter coupled to an opposite end of the armature. The method includes commencing a closing operation of the actuator using the manual actuation device to move the armature towards a closed latch position, detecting that the actuator is being manually closed, and energizing the winding to assist moving the armature to the closed latch position when the armature gets to a predetermined distance from the closed latch position.

A bistable solenoid valve device for a fluid system includes a bistable solenoid valve and a detection device. The bistable solenoid valve has a permanent magnet yoke, an armature configured to be displaced between a first armature position for contact against a first core to form an air gap with a second core and a second armature position for contact against the second core to form an air gap with the first core. The bistable solenoid valve device further includes a detection device configured to evaluate and/or measure a first inductance of the first armature coil, and evaluate and/or measure a second inductance of the second armature coil without displacement of the armature, to compare the inductance of the first armature coil and the inductance of the second armature coil, and to output a state signal that indicates the armature position.

Some embodiments provide irrigation valve control apparatuses comprising: a solenoid configured to cooperate with a plunger; an input stimulus source coupled with the solenoid and configured to apply an input stimulus while a plunger drive signal is not being applied and that is sufficiently small to not cause the plunger to move; sampling circuitry configured to measure one or more voltage measurements corresponding to one or more voltages across the solenoid, wherein the one or more voltage measurements are dependent upon the current position of the plunger relative to the solenoid; and control circuitry cooperated with the sampling circuitry to receive the one or more voltage measurements from the sampling circuitry, wherein the control circuitry is configured to determine whether the plunger is in one of the open and closed positions based on the one or more voltage measurements.

A controller of an electromagnetically driven reciprocating pump influences velocity of the magnetic armature by switching voltage applied to the electromagnet depending on the position of the magnetic armature, its position determined from state variables of the electromagnet. A processor calculates electrical resistance of the magnetic coil from the voltage and current measured by the measuring device, and calculates the temporal change of the linked magnetic flux in the electromagnet from the electrical voltage, the current and the resistance of the magnetic coil, and calculates the linked magnetic flux in the electromagnet from an earlier magnetic flux and from the temporal change, and determines the position of the magnetic armature from the linked magnetic flux in the electromagnet and the electrical current through the magnetic coil, and switches the voltage at the magnetic coil by the switching device depending on the position of the magnetic armature.

A current control device includes a target setting unit, a storage unit, an oil pressure ratio calculation unit, a specific current detection unit and a correction unit. The target setting unit adds a dither amplitude to a target current so that the current of the solenoid periodically changes at a dither cycle period longer than a PWM cycle period of the solenoid. The storage unit stores a stroke-current relationship between a stroke of the spool and the current of the solenoid. The oil pressure ratio calculation unit calculates an oil pressure ratio which is a value calculated by dividing an amplitude of the output oil pressure by an average value of the output oil pressure. The specific current detection unit detects a specific current based on the oil pressure ratio. The correction unit corrects the stroke-current relationship based on the specific stroke and the specific current.

In an electromagnetically moving device 100, a magnetic-flux variation measuring unit 3 is placed at a position which is outside a closed magnetic path established when a movable core 6 and a stationary core 5 are being attached to each other due to permanent magnets 7, and at which a leakage magnetic-flux variation due to movement of the movable core 6 can be measured, so that a behavior of a movable part in a switch, etc. is estimated such that an inflection point time is calculated from the measurement of time-series data of the magnetic-flux variation.

An image stabilization apparatus includes a movable member configured to hold an image stabilization optical element, a fixed member holding the movable member movably in a direction crossing an optical axis, an electrical element mounted on the movable member, and a flexible sheet member electrically connecting the electric element to the fixed member. The flexible sheet member is fixed to the movable member and the fixed member so that the flexible sheet member is bent between the movable member and the fixed member.