Structure composition of electromagnetic contactor

Electromagnetic contactor is mainly composed of transmission device (electromagnetic mechanism), contact device (actuating mechanism) and arc extinguishing device.

1. Electromagnetic mechanism

The electromagnetic mechanism includes three parts: a moving iron core (armature), a static iron core and an electromagnetic coil. Electric current is passed through the electromagnetic coil to generate electromagnetic attraction to drive the contacts.

Electromagnetic mechanism is one of the important components of electromagnetic contactor. The electromagnetic mechanism is composed of coil, iron core (static iron core), armature (moving iron core), pole shoe, iron yoke and air gap. The coil and iron core in the electromagnetic mechanism are not moving in the working state; the armature is movable.

The electromagnetic mechanism converts the electromagnetic energy generated by the electromagnetic coil into mechanical energy through the action state and action process of the armature and the corresponding mechanical mechanism to drive the contacts to close or open to achieve the control purpose of the controlled circuit.

2. Contact device

There are many structural forms of contacts, which can be divided into main contacts and auxiliary contacts according to the control circuit;

According to its original state, the contacts are divided into: normally open contacts and normally closed contacts;

According to its structure, the contacts are divided into: bridge-shaped contacts and finger-shaped contacts.

3. Arc extinguishing device

The arc extinguishing hood is an insulating and high temperature resistant arc extinguishing device made of clay and asbestos cement. It is a simple arc extinguishing device.

When using the arc extinguishing cover device to extinguish the arc, the longitudinal slit arc extinguishing method is generally used in the arc extinguishing cover to extinguish the arc.

Commonly used arc extinguishing devices: arc extinguishing cover (arc resistant clay, asbestos cement, arc resistant plastic), arc extinguishing grid (arc resistant grid-copper-plated thin steel sheet), magnetic blowing arc extinguishing device (a series of contacts in the circuit Arc quenching coil).

4. Other components, including reaction springs, buffer springs, transmission mechanisms and housings, etc.