Overcurrent and overvoltage protector with bimetallic strip temperature switch

Abstract

The invention relates to an overcurrent and overvoltage protector with a bimetallic strip temperature switch. The protector comprises a PTC (positive temperature coefficient) thermistor chip (1), a piezoresistor chip (2) and the bimetallic strip temperature switch (3), wherein one side electrode of the PTC thermistor chip (1) is connected with one side electrode of the piezoresistor chip (2) through soldering tin to form a common terminal which is led out by a first lead foot (6); a metal shell of the bimetallic strip temperature switch (3) is connected with the other side electrode of the PTC thermistor chip (1) through the soldering tin; a first leading-out terminal (4) of the bimetallic strip temperature switch (3) is connected with the other side electrode of the PTC thermistor chip (1); a second leading-out terminal of the bimetallic strip temperature switch (3) is led out by a second lead foot (5); and the other side electrode of the piezoresistor chip (2) is led out by a third lead foot (7). According to the overcurrent and overvoltage protector with the bimetallic strip temperature switch, a post-stage circuit is protected, and the functions of automatic power off and automatic power on are realized.

Description

[0001] technical field [0002] The invention relates to the structure of an over-current and over-voltage protector, in particular to an over-voltage and over-current protection device capable of automatic power-off and automatic power-on in the protection of nonlinear power supplies. [0003] Background technique [0004] In the combination application of PTC thermistor and varistor in nonlinear power supply, there are generally the following three methods, such as figure 1 , figure 2 , image 3 As shown (in the attached figure, PTCR means PTC thermistor, RV means varistor): [0005] like figure 1 In the circuit shown, the varistor is used in various electronic circuits to absorb lightning induction pulse transient overvoltage due to its excellent nonlinear characteristics, but due to various abnormal reasons, the varistor often fails or even catches fire and explodes. In order to solve this problem, designers often have to consider increasing the varistor voltage va...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to propose an overcurrent and overvoltage protector with a bimetal strip temperature switch, which can solve the problem that the existing composite PTC thermistor cannot be applied to industrial control occasions with automatic power-off reset and unattended on-site environmental problems

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