Contactor system for low-voltage breaker

Abstract

The invention provides a contact system for a low voltage circuit breaker, belonging to the low voltage electric appliance technical field; the invention comprises an upper contact and a lower contact which are corresponding to each other, wherein the upper contact is fixed on a second electric conduction pole which is used to be connected with a rotating shaft of an operating mechanism of a circuit breaker, and the lower contact is fixed on the front end of a first electric conduction pole of which the back end pivotally arranged on a bracket fixed on a base of the circuit breaker; the contact system is characterized in that: an electric conduction component extends with an arc strike part which is used to receive the electric arc from the contact surface of the lower contact and transfer the received electric arc on the part approximately corresponding to the front end of the lower contact; the contact system has the advantages that: when the upper contact and the lower contact are disassembled, the generated electric arc can be quickly stretched, and the increased electric arc voltage neutralizes the power voltage, which reaches the effect of limiting the increasing of the short circuit current, and the electric arc on the contact surface of the lower contact can be quickly transferred by the arc strike part, and the burning of the electric arc on the lower contact is avoided, thereby ensuring that the circuit breaker has the desirable opening-breaking capability.

Description

technical field [0001] The invention relates to a contact system of a low-voltage circuit breaker, in particular to a contact system of a current-limiting low-voltage circuit breaker, and belongs to the technical field of low-voltage electrical appliances. Background technique [0002] The duty of the circuit breaker is to break and connect the circuit, especially to cut off the power supply when the circuit is abnormal, so as to protect the circuit and equipment. The breaking and making of the circuit breaker are achieved by the separation and contact between the contact pair, that is, the upper contact and the lower contact. In the process of disconnecting the contacts to cut off the circuit, an arc will inevitably be generated between the contacts. Since the arc has a high temperature of thousands of degrees Celsius, whether the arc root of the arc can be quickly transferred from the contacts not only determines the breaking of the circuit breaker ( Also known as breakin...

AI Technical Summary

Problems solved by technology

[0005] The contact system shown in Figure 2 has the problem of taking into account one thing and losing another. The so-called focus on this means that the lower contact 1 is designed as a movable structure, which is more beneficial to elongate the arc; the so-called loss of the other means that the lower contact 1 cannot be made The contact surface of the head 1, that is, the arc 7 on the working surface of the lower contact is transferred rapidly, and the arc 7 is always burning on the lower contact 1 from generation to extinguishment. Therefore, on the one hand, the service life of the lower contact 1 will be reduced, and on the other hand It will cause the concentration of metal vapor in the arc extinguishing chamber to increase, which in turn will constrain the further improvement of the breaking capacity of the circuit breaker.

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