A small circuit breaker

Abstract

The invention discloses a miniature circuit breaker. The miniature circuit breaker comprises a tripping part and an opening and closing part, wherein the tripping part comprises a movable hanging hole and a tripping rod, the movable hanging hole moves from a first position to a second position under the influence of overcurrent, the front end of the tripping rod is movably connected to the interior of the movable hanging hole, the tripping rod is fixed to a base plate through a first rotary shaft, a first spring is connected to the tail end of the tripping rod, and force enabling the tripping rod to rotate clockwise along the first rotary shaft is supplied by the first spring; the opening and closing part comprises a handle and a connecting piece, the handle rotates in a reciprocating mode between a third position and a fourth position with a second rotary shaft as the center, the connecting piece is movably connected with a protrusion at the lower end of the handle, a guide rod groove is also formed in the lower end of the handle, the tripping rod penetrates through the guide rod groove, a second spring is arranged between the tripping rod and a third rotary shaft located below the tripping rod, force enabling the tripping rod to rotate anticlockwise along the first rotary shaft is supplied by the second spring, and the connecting piece is movably connected to the third rotary shaft and rotates along the third rotary shaft; a wire connecting end is connected to the side wall of the bottom end of the connecting piece and moves along with the connecting piece, the wire connecting end is disconnected with a contact point, and then a circuit is opened.

Description

technical field [0001] The invention relates to a circuit breaker, in particular to a small circuit breaker. Background technique [0002] Usually, a miniature circuit breaker (Miniature Circuit Breaker, MCB) is installed on the circuit to protect the household or industrial switchboard system. . [0003] Utility model patent No. 20-0462420 discloses a small molded case circuit breaker. When an abnormal current occurs on the circuit, the tripping device trips. The trip device consists of a trip coil, a movable coil that moves under the influence of electromotive force in said trip coil and is pressurized in the direction of releasing the locking of the lower end of the trip bar and the latch when an abnormal current occurs, and is deformed due to thermal deformation when an abnormal current occurs. Consists of a bimetal that pushes the upper portion of the trip bar back to the latch-released position. [0004] The small molded case circuit breaker of the registered utilit...

AI Technical Summary

Problems solved by technology

[0004] The small molded case circuit breaker of the registered utility model invention No. 20-0462420 adopts a structure in which the trip lever is rotated in the direction of unlocking the latch when an abnormal current occurs, and includes a trip coil and a movable iron core. Electromagnetic tripping devices and thermal tripping devices with bimetal strips can improve the reliability of the tripping action, but the disadvantage is that the installation structure of the tripping device becomes complicated, and the hinge shaft of the latch is the center. The iron core is located at the lower end, and the bimetal sheet is located at the upper end, which takes up a lot of installation space for the switchgear, which is not conducive to making miniaturized circuit breakers

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