Specification

Electromagnetic contactor (contactor) refers to an electrical appliance that
uses the current flowing through the coil to generate a magnetic field in
industrial electricity to close the contact so as to control the load. The
contactor is composed of electromagnetic system (armature, stator core,
electromagnetic coil), contact system (normally open contact and normally
closed contact) and arc extinguishing device.
Structural composition
Electromagnetic contactor is mainly composed of transmission device
(electromagnetic mechanism), contact device (actuator) and arc extinguishing
device.

1. Electromagnetic mechanism


The electromagnetic mechanism includes three parts: moving core (armature),
static core and electromagnetic coil. The electromagnetic coil is connected
with current to generate electromagnetic suction and drive the contact to act.


Electromagnetic mechanism is one of the important parts 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 do not move 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 contact to close or open, so as to realize the control purpose of the
controlled circuit.


2. Contact device


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


The contact is divided into normally open contact and normally closed contact
according to its original state;


The contact is divided into bridge contact and finger contact according to its
structural form.


3. Arc extinguishing device


Arc extinguishing cover is an insulated 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 seam arc extinguishing method is generally used in the arc
extinguishing cover.


Common arc extinguishing devices: arc extinguishing cover (arc resistant clay,
asbestos cement and arc resistant plastic), arc extinguishing grid (arc
resistant grid sheet copper plated thin steel sheet), magnetic blowing arc
extinguishing device (an arc extinguishing coil is connected in series in the
contact circuit).


4. Other components, including reaction spring, buffer spring, transmission
mechanism and shell, etc.