Closed mode overheat protective technology

Abstract

Overheat protection technique includes following parts: (1) using piezoresistor and new type short circuit protector arranged in parallel; (2) new type short circuit protector uses heat molten mass; (3) the heat molten mass is divided into two portions: a hollow body part, and solid part. Short circuit protector includes main body with substrate of insulator, thermal deformation modules (TDM), electrode, and external cap of insulator. The substrate of insulator includes through holes for containing TDM, and mounting holes for installing external caps. The substrate of insulator also sets up position for fixing metal electrode. TDM is composed of small conduits and large sleeves prepared from thermal deformation material, and temperature controlled weldable fusible alloy in use for filling to the large sleeves. The external cap includes extended feet and slots for feet. Changing open circuit mode in current technique to close mode, the invention raises safety coefficient.

Description

technical field [0001] The invention relates to an overheat protection method in the electrical field, in particular to a closed-circuit mode overheat protection method. Background technique [0002] With the rapid development of modern electronic and electrical technology, more and more electronic and electrical equipment (such as: electronic equipment, network equipment, household appliances, electricity, electrical, medical, computer integrated circuits, etc.) are widely used in various fields, and At the same time, these electronic and electrical equipment are all subjected to lightning surge natural disasters and various electromagnetic interference surge currents and surge voltages without exception, causing these devices to fail to work normally, and in severe cases, they will catch fire, burn, explode, etc. [0003] An effective way to solve the above problems is to connect one or more groups of MOV zinc oxide varistors in parallel at the input terminals of these dev...

AI Technical Summary

Problems solved by technology

This technology refers to packaging the varistor and the thermal fuse in series, and using heat conduction to conduct the heat generated by the leakage current on the varistor to the thermal fuse. When the temperature rises to the set temperature of the thermal fuse, the thermal fuse Fusing, cutting off the varistor from the circuit, in addition to the life and reliability problems of the thermal fuse, there are also the following problems in using the thermal fuse to protect the varistor from overheating: the heat conduction path is long, the response speed is too slow, and in its structure The upper heat is first transmitted to the thermal fuse shell through a certain insulating material, then to the internal filling material of the thermal fuse, and finally to the melt of the thermal fuse. Therefore, the response speed of the thermal fuse is determined to be slow.

[0012] First, reduce some important characteristic parameters of varistors, such as flow capacity, life, power frequency withstand voltage, and high frequency characteristics in exchange for incomplete protection of varistors, which actually violates the use of varistors to a certain extent. The original meaning of the varistor

[0013]Second, these technologies adopt the open circuit protection mode when the varistor fails, and the basis for judging the failure is the temperature rise of the varistor

Due to structural reasons, it must be detected by temperature gradient. Therefore, the heat conduction is slow and the response is slow. At the same time, it is also affected by the temperature of the surrounding environment. Therefore, it is impossible to quickly and accurately judge the fault to trigger reliable action.

[0014]Third, the adaptability of the structure is poor, different structures are required for products of different specifications and sizes, and the cost is high

[0015] Fourth, due to the complex structure and manufacturing process and the use of low melting point (about 120 degrees) solder, manual assembly operations must be used, which is very inefficient

[0016]Fifth, due to the open circuit mode, the user cannot quickly and simply judge whether the piezoresistor has failed during use, and must be removed from the device for inspection and maintenance cycle and high cost

[0017] Therefore, there are defects such as slow response, poor shock resistance, consumables, high energy consumption, unstable work, and inaccurate temperature control in the prior art; because of its complex structure and many varieties, the operation is complicated and the failure rate is extremely high. The production efficiency is low and the scope of application is small, which brings some troubles to customers, and the maintenance of products is quite troublesome and expensive, which limits its market field

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