An overall heat treatment method for a coil assembly with a bimetal sheet and the coil assembly

Abstract

An overall heat treatment method for a coil assembly with a bimetal strip, comprising the following steps: a. First heat treat the bimetal strip, and then fix it with the terminal of the coil by spot welding to form a coil and a bimetal welded thereto The coil assembly of the sheet; b. Put the coil assembly as a whole workpiece to be heat-treated into the high-temperature aging box; c. Operate the high-temperature aging box to heat up, the maximum temperature is less than 130°C, and the heating rate ranges from 0.2°C to 10°C / min; d. Turn off the power of the high-temperature aging box and keep it warm for a period of time; e. Open the door of the high-temperature aging box to cool the whole workpiece in the air with the furnace until it drops to room temperature and take it out. The coil assembly manufactured by this method includes a coil wound on a coil frame and a bimetallic sheet, and the bimetallic sheet is welded and fixedly connected to the terminal of the coil. By heat-treating the coil and the bimetal as a whole, the production efficiency can be effectively improved, the manufacturing cost can be reduced, and the repair rate of finished products can be significantly reduced.

Description

technical field [0001] The invention relates to a heat treatment method for electrical components, in particular to an overall heat treatment method for a coil component with bimetallic strips, and also relates to a coil component with bimetallic strips manufactured by the method. Background technique [0002] Coil components with bimetal strips are widely used components, such as low-voltage circuit breakers, which are commonly used to achieve instantaneous tripping and delayed tripping. Coil assemblies with bimetal strips generally include an induction coil wound on the bobbin of the coil and a bimetal strip connected by spot welding to terminals of the coil. As we all know, the bimetal sheet of the coil assembly is a temperature-sensitive element, which bends and changes with the change of its heating temperature, and requires a functional relationship between its temperature change and bending change (ie, the temperature bending characteristic ) is stable, and it is als...

AI Technical Summary

Problems solved by technology

However, in the process of connecting the coil and the bimetal by spot welding, due to the high temperature of the spot welding, heat and force must be applied to the bimetal, which will change the internal stress of the bimetal, resulting in The temperature bending characteristics of the bimetal sheet change, so that the temperature curvature of the bimetal sheet will be inconsistent, which greatly deteriorates the consistency of the temperature bending characteristics

The existing way to solve this problem is to select good consistency and put it on the same product, but due to the limited means of identifying consistency, it will still cause the following two problems: one is that this selection must invest a large amount of man-hours , which restricts production efficiency and increases manufacturing costs; second, it is still inevitable that there will be poor consistency, resulting in a high repair rate of finished products and serious waste problems

And because it is generally believed that the bimetallic sheet has been overheated before spot welding, there is no need to process it again. Therefore, existing manufacturers have not thought of needing to process it again.

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