Patch type fuse and batch manufacturing method thereof

Abstract

The invention discloses a patch type fuse which comprises an insulating inner shell, an insulating outer shell and a metal sheet. The insulating inner shell is provided with a first side wall and a bottom surface, the insulating outer shell is provided with a second side wall and a top surface, the insulating outer shell covers the periphery of the insulating inner shell, the first side wall, the top surface and the bottom surface jointly define an inner cavity, and the metal sheet comprises a fuse link located in the inner cavity and extension parts bent and extending from the two sides of the fuse link. The extension parts extend out from the positions between the first side walls and the corresponding second side walls to form end electrodes, and the high-temperature thermoplastic resin is filled in the inner side of the top face and the positions between the first side walls and the second side walls and enables the insulating inner shell and the insulating outer shell to be fixedly connected. And the high-temperature thermoplastic resin wraps the extension part of the metal sheet located at the top of the first side wall and the extension part located between the first side wall and the second side wall. The bonding surfaces between the insulating inner shell and the insulating outer shell are placed on the top surface and the side surface of the product and have a good heat dissipation relationship with the external environment, so that the fuse has good low temperature rise performance.

Description

technical field [0001] The invention relates to a chip type fuse, in particular to a fuse with low-temperature rise performance and a batch manufacturing method. Background technique [0002] With the development of industries such as power batteries and small energy storage tools, there is an increasing demand for high-current surface-mount fuse products, and its temperature rise characteristics are particularly important. Considering the structural design of the product itself, the traditional shell-shaped fuse products use leaded solder to form an electrical connection between the internal metal melt and the external end cap through high-temperature melting welding and similar methods, and with the product itself As the rated current is getting higher and higher, the structure and main performance indicators of products obtained by welding technology, such as the limitations of temperature rise, are gradually becoming prominent, and a new product design is required to mee...

AI Technical Summary

Problems solved by technology

The advantage of this structure is mainly to reduce the contact resistance between the metal melt and the end electrodes, but the disadvantages are also obvious. Because the silicone resin is at the bottom of the product, it is difficult to dissipate heat, and it is in direct contact with the metal sheet of the fuse, which is easy to Cause heat accumulation, and its sealing resin will age with the increase of product use time and temperature, which will cause the end electrodes and fuses to fall off

Chinese patent 201320839953.8 uses a ceramic material bottom cover and high thermal conductivity adhesive as the sealing layer at the opening end of the insulating shell, but the patent still clearly points out that the high temperature generated by the fuse will quickly heat up the ceramic material and eventually cause the temperature of the ceramic material to be higher than that of the metal The temperature of the melting point, so that the fuse body will fall off the main board of the electronic device

Considering this potential failure, Chinese patent 201680085101.0 designed a base with complex structure to replace this sealing layer. The production process of the product is relatively complicated, and the material dimensional accuracy is very high; The inner shell of the bump and the outer shell with grooves are connected by a snap-fit ​​insulating shell structure, but because the outer shell has a certain elasticity, it is convenient to press the groove of the outer shell into the bump of the inner shell Therefore, the material of the shell can only be plastic or bakelite, which has insufficient heat resistance, and the insulating shell of the product may be deformed after reflow soldering

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