Snap-in adjustable electromagnetic release

Abstract

A snap-fit ​​adjustable electromagnetic tripper belongs to the technical field of circuit breakers. It includes a current-carrying wire, a first bracket fixed on the current-carrying wire, a second bracket hinged on the first bracket, an armature fixed on the second bracket, and an armature fixed on the current-carrying wire and corresponding to the armature. The iron core, the iron core includes first and second U-shaped cores, and the first and second U-shaped cores are fixed with the current-carrying wires. Advantages: Due to the use of the first and second U-shaped cores, two independent magnetic circuits are formed by the first and second U-shaped cores and the armature, so that the first and second U-shaped cores form with the armature Four magnetically conductive air gaps δ, the magnetically conductive area S can be increased, and the number of ampere-turns passed through the first U-shaped core is large, so even when the current-carrying wire flows through a small current, a large electromagnetic attraction will be generated , so as to ensure sensitive and reliable tripping, and can expand the current regulation range from the original 200-250A in the prior art to 125-250A.

Description

technical field [0001] The invention belongs to the technical field of circuit breakers, and in particular relates to a snap-fit ​​adjustable electromagnetic tripper installed in a low-voltage molded case circuit breaker. Background technique [0002] The structure of the clapping type adjustable electromagnetic tripper widely used in the prior art consists of figure 1 As shown, it includes a current-carrying wire 1, first and second brackets 2, 3, an armature 4 and an iron core 5, the first bracket 2 is fixed on the current-carrying wire 1, the second bracket 3 is hinged with the first bracket 2, and the armature 4 is fixed to the second bracket 3 , and the iron core 5 is fixed to the current-carrying wire 1 and corresponds to the armature 4 . The snap-fit ​​adjustable electromagnetic release of this structure can be applied to large current setting and adjustment. For example, the frame level of the circuit breaker is 250A, and its current adjustment range is 200-250A, ...

AI Technical Summary

Problems solved by technology

However, when the above structure is used for small current setting, for example, the frame level of the circuit breaker is 250A, and the current adjustment range is required to be below 200A, according to the relation F ∞ ( I · N ) 2 S δ 2 , Because of the above structure, the number of turns N, magnetic permeability air gap δ and the area S of the magnetically conductive air gap remain unchanged. At this time, the current is small, and the attraction force provided by the iron core 5 is also small, so the iron core 5 is not easy to be attracted. Therefore, the tripping of the electromagnetic release is not sensitive. Tripping is unreliable and cannot play a protective role

That is to say, the adjustment range of the current in a frame is limited. Taking the above-mentioned circuit breaker frame level of 250A as an example, the current setting range is only 200-250A, so the adjustment ability is limited.

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