One embodiment describes an operating coil driver circuitry, which includes a control circuitry that outputs a trigger signal and a reference voltage; an operational amplifier that compares the reference voltage to a node voltage, in which the node voltage is directly related to current flowing through an operating coil of a switching device and the operational amplifier outputs a logic high signal when the node voltage is higher than the reference voltage and outputs a logic low signal when the node voltage is lower than the reference voltage; and a flip-flop that outputs a pulse-width modulated signal to instruct a switch to supply a desired current to the operating coil based at least in part on the trigger signal and the signal output by the operational amplifier.

In some embodiments, a DC relay includes a pair of fixed contacts fixedly installed on one side of a frame, a movable contact movably installed below the pair of fixed contacts and brought into contact with the pair of fixed contacts or separated therefrom, an insulating plate installed below the movable contact, a contact spring provided between the movable contact and the insulating plate, a plate installed below the insulating plate and including a through hole formed in a central portion thereof, a fixed core inserted from above the plate through the through hole and including a shaft hole formed at the center thereof, an anti-noise pad provided between the fixed core and the insulating plate, a movable core installed to be linearly movable below the fixed core, and a shaft installed to penetrate through the through hole.

A self-holding magnet has a spring (accumulator spring) and a first armature. The self-holding magnet is capable of holding the first magnet armature against the spring force in a lift position which is determined by a stop. The stop determines a remaining air gap of a working air gap. The magnetic circuit of the self-holding magnet has a magnetic shunt with particularly low reluctance of the same order of magnitude as a series reluctance of the remaining working air gap(s). The working air gap(s) and the shunt are magnetically connected in parallel with the flow generated by a permanent magnet but in series with the flow generated by the trigger coil. The self-holding magnet additionally has at least one positive feedback device such as a compressible resilient stop or a shunt.

A self-holding magnet has a spring (accumulator spring) and a first armature. The self-holding magnet is capable of holding the first magnet armature against the spring force in a lift position which is determined by a stop. The stop determines a remaining air gap of a working air gap. The magnetic circuit of the self-holding magnet has a magnetic shunt with particularly low reluctance of the same order of magnitude as a series reluctance of the remaining working air gap(s). The working air gap(s) and the shunt are magnetically connected in parallel with the flow generated by a permanent magnet but in series with the flow generated by the trigger coil. The self-holding magnet additionally has at least one positive feedback device such as a compressible resilient stop or a shunt.

A bistable relay and a bistable actuator are provided. The bistable actuator includes a magnetic latching mechanism and an electromagnet. The magnetic latching mechanism includes a rotation shaft, a pillar-shaped permanent magnet, a columnar hollow magnetic conductor and two shells, and operates between a first and second stable states. The columnar hollow magnetic conductor surrounds the pillar-shaped permanent magnet wrapping the rotation shaft, and maintains a gap with the pillar-shaped permanent magnet. The electromagnet is connected to the columnar hollow magnetic conductor for driving the pillar-shaped permanent magnet to rotate, so as to switch the magnetic latching mechanism to the stable state. During a process that the magnetic latching mechanism is switched to the stable state, the rotation shaft rotates synchronously along with the magnetic latching mechanism to drive an impact system to move relative to a contact system, so as to contact or disconnect the contact points.

A bistable relay and a bistable actuator are provided. The bistable actuator includes a magnetic latching mechanism and an electromagnet. The magnetic latching mechanism includes a rotation shaft, a pillar-shaped permanent magnet, a columnar hollow magnetic conductor and two shells, and operates between a first and second stable states. The columnar hollow magnetic conductor surrounds the pillar-shaped permanent magnet wrapping the rotation shaft, and maintains a gap with the pillar-shaped permanent magnet. The electromagnet is connected to the columnar hollow magnetic conductor for driving the pillar-shaped permanent magnet to rotate, so as to switch the magnetic latching mechanism to the stable state. During a process that the magnetic latching mechanism is switched to the stable state, the rotation shaft rotates synchronously along with the magnetic latching mechanism to drive an impact system to move relative to a contact system, so as to contact or disconnect the contact points.

In the electromagnetic operating device, the driving power supply is composed of two types of power supplies: a capacitor power supply serving as a power supply which is for performing opening/closing operation in a normal time with respect to the vacuum valve; and a DC power supply which is for performing opening/closing operation in an emergency. The capacitor power supply which is for performing opening/closing operation in the normal time includes: capacitors that store electric power to be supplied to the electromagnetic coil; and a control board which controls a current to be supplied from the capacitors to the electromagnetic coil in response to an open-contact or close-contact command to the vacuum valve. Then, the DC power supply which is for performing opening/closing operation in the emergency is to directly supply DC electric power to the electromagnetic coil.

An electrical switch comprising a solenoid assembly including a core casing having a first bearing site and a bearing bush having a second bearing site, an armature movably borne in a switching direction at the first bearing site, and an armature shaft fixed to and movable with the armature and movably borne in the switching direction at the second bearing site.

An electrical switch comprising a solenoid assembly including a core casing having a first bearing site and a bearing bush having a second bearing site, an armature movably borne in a switching direction at the first bearing site, and an armature shaft fixed to and movable with the armature and movably borne in the switching direction at the second bearing site.

In some embodiments, a DC relay includes a pair of fixed contacts fixedly installed on one side of a frame, a movable contact movably installed below the pair of fixed contacts and brought into contact with the pair of fixed contacts or separated therefrom, an insulating plate installed below the movable contact, a contact spring provided between the movable contact and the insulating plate, a plate installed below the insulating plate and including a through hole formed in a central portion thereof, a fixed core inserted from above the plate through the through hole and including a shaft hole formed at the center thereof, an anti-noise pad provided between the fixed core and the insulating plate, a movable core installed to be linearly movable below the fixed core, and a shaft installed to penetrate through the through hole.