Sealed type direct current contactor with high breaking capacity

Abstract

The invention relates to a sealed type direct current contactor with high breaking capacity. The sealed type direct current contactor with high breaking capacity is characterized in that a reaction spring and a bridge terminal assembly are respectively arranged at the lower end and upper end of a push rod; a moving iron core is arranged in an electromagnetic coil and is connected with the push rod; a contact assembly is fixedly arranged above the electromagnetic coil; a casing and an arc extinguishing cover form a sealing cavity; an action system, a contact system and a magnetic circuit system are respectively arranged in the sealing cavity; the arc extinguishing cover comprises a metal ceramic sheet, a permanent magnet and an upper cover; the upper cover is connected and sealed with the casing; the metal ceramic sheet and the permanent magnet are respectively and fixedly arranged at the two ends and two sides of the upper cover. The sealed type direct current contactor has the beneficial effect that the electric arc generated by the disconnecting of a main contact is effectively extended by the metal ceramic sheet in a strong magnetic field which is generated by the permanent magnet, a metal oxide in the metal ceramic sheet can be decomposed by the effect of the electric arc to absorb a large amount of heat, and a large amount of electric arc energy is consumed, so that the electric arc can be quickly extinguished.

Description

technical field [0001] The invention relates to the field of low-voltage electrical switches, in particular to a sealed DC contactor. Background technique [0002] As one of the important components in the automatic control system, the DC contactor is specifically an automatic switcher used to switch on or off the DC main circuit with load or a large-capacity control circuit. The main control object is the motor, and it is also used For other electrical loads, such as electric heaters, electric welding machines, lighting equipment, etc. At the same time, the DC contactor can not only switch on and off the circuit, but also has the function of low voltage release protection. In addition, the contactor has a large control capacity, which can meet the operation requirements of frequent operation and remote control. [0003] The electromagnets of existing DC contactors generally use double-winding coils. Specifically, a pair of auxiliary normally closed contacts is set at the ...

AI Technical Summary

Problems solved by technology

[0003] The electromagnets of existing DC contactors generally use double-winding coils. Specifically, a pair of auxiliary normally closed contacts is set at the bottom of the housing. The contactor must form a non-sealed structure, and between the small cap and the shell, between the electromagnet, the mounting plate, and the seat plate assembly, the bonding surface between the cap cover and the seat plate assembly cannot prevent water, salt spray, Harmful substances such as dust enter the interior to cause rust, contact oxidation, and electrical insulation performance reduction

[0004] At the same time, the existing DC contactors still have the problems of excessive wear of the contacts when breaking large currents, and too long arcing time when breaking small currents

Images