CN205751736U - A kind of varistor with Double-side hot protection - Google Patents

Abstract

The utility model discloses a kind of varistor with Double-side hot protection; including shell; described enclosure is provided with varistor MOV; the first varistor MOV metal electrode and the second varistor MOV metal electrode it is provided with on described varistor MOV; described enclosure is provided with heat conduction embedding silica gel, and described enclosure is respectively arranged with major loop Thermal Cutoffs TCO1, minor loop Thermal Cutoffs TCO3 and major loop Thermal Cutoffs TCO2 in varistor MOV both sides.This utility model is respectively provided with a Thermal Cutoffs in varistor both sides; it is carried out Double-side hot protection; before producing high heat after pressure responsive resistor failure; varistor abnormal heating amount can not only be utilized faster; shorten Thermal Cutoffs movement time; can also reduce further varistor because unilateral focus is too high the risk of puncture short, circuit can be cut off effectively and rapidly to prevent varistor ignition.

Description

A kind of varistor with Double-side hot protection

Technical field

This utility model is about the piezoresistive surge protector in lightning protection field, is specifically related to one and has The varistor of Double-side hot protection.

Background technology

Varistor MOV due to special conductive characteristic and cheap and be widely used in electrical appliance and other In electronic product, play the effects such as overvoltage protection, lightning protection, surge current suppression, amplitude limit, de-noising, protection semiconductor components and devices.

During life-time service, due to its shelf-life and external factor, as made moist, leakage current increase cause MOV heating, The reasons such as sustained overvoltage, MOV the most inevitably there will be aging deterioration phenomenon.When aging deterioration is to certain After degree, MOV shows leakage current and increases, and caloric value continues to increase, and body temperature rises, and varistor is the most breakdown leads Cause catching fire.It is thus desirable to MOV carries out Thermal protection, traditional way is a Thermal Cutoffs and MOV to be connected and temperature Degree electric fuse is against MOV side, and the two is potted in same shell or passes through resin-encapsulate together, during MOV abnormal heating, and heat Amount be transmitted on Thermal Cutoffs, when temperature rises to Thermal Cutoffs operating temperature, Thermal Cutoffs fuse, by MOV from Circuit Interrupt is opened, thus protects MOV, and such as Chinese patent 200510118249.3 " is provided with the pressure-sensitive of alloy-type temperature fuse Resistance ".But this patent there is the problem that Thermal Cutoffs only with varistor one side contacts, with varistor another Side there is no any heat conduction path so that the heat produced during varistor deterioration cannot be fully utilized, and Thermal Cutoffs is not Front action can be deteriorated further to cut off circuit at varistor.

Furthermore, in April, 2011 Meteorology Publishing House publish the superfine chief editor of Li Xiang " surge protector (SPD) principle with should With " page 69 mention: varistor is owing to self preparing material and technological reason, and varistor there may be Density inhomogeneity (as many in space, uneven etc.), then leakage current skewness, result in temperature distributing disproportionation even.When existing uneven, Producing a focus on element, along with flowing through the increase of focus channel current, element punctures the most at last.In large-size components It is frequently seen this phenomenon, because whole each point temperature difference of this element is the biggest.In other words, if varistor both sides are deposited At focus, then the temperature difference of both sides is big.

Chinese patent 201520376567.9 " a kind of Thermal protection varistor and combinations thereof element " discloses a kind of heat and protects Protecting resistance, wherein the second metal electrode of varistor and the first electrode of Thermal Cutoffs are same electrode, varistor Second metal electrode by insulating heat-conductive parts and auxiliary heat conduction electrode mediate contact, and auxiliary heat conduction electrode again with Temperature protection Second electrode of silk is linked together by welding or crimping mode, it is possible to the abnormal heating amount of varistor two positive and negative passed It is delivered on two pins of Thermal Cutoffs, improves the safety in utilization of varistor.But, due to the second of varistor Second electrode of metal electrode not in direct contact Thermal Cutoffs, therefore the abnormal heating at the second metal electrode of varistor Amount just must can be transmitted to the second electrode of Thermal Cutoffs, i.e. insulating heat-conductive parts and auxiliary heat conduction by two heat transfer mediums Electrode, is affected by material thermal conductivity and interface resistance, and the abnormal heating amount of varistor second fails to all, rapidly It is delivered to the second electrode of Thermal Cutoffs, varistor both sides precisely can not be protected.

Utility model content

In order to protect varistor MOV both sides simultaneously, solving above-mentioned the deficiencies in the prior art, this utility model carries Go out a kind of varistor with Double-side hot protection.

For solving the problems referred to above, this utility model adopts the following technical scheme that a kind of pressure-sensitive electricity with Double-side hot protection Resistance, including shell, described enclosure is provided with varistor MOV, and described varistor MOV is provided with the first varistor MOV metal electrode and the second varistor MOV metal electrode, described enclosure is provided with heat conduction embedding silica gel, described shell Inside is respectively arranged with major loop Thermal Cutoffs TCO1, minor loop Thermal Cutoffs TCO3 and master in varistor MOV both sides Loop temperature electric fuse TCO2, described major loop Thermal Cutoffs TCO1 is by low-melting alloy silk, the first major loop Temperature protection Silk TCO1 pin, the second major loop Thermal Cutoffs TCO1 pin, alloy flux disconnected agent and outer protecting shell body is constituted, and described master returns Road Thermal Cutoffs TCO2 is protected by low-melting alloy silk, the first major loop Thermal Cutoffs TCO2 pin, the second major loop temperature Disconnected agent fluxed by danger silk TCO2 pin, alloy and outer protecting shell body is constituted, and described minor loop Thermal Cutoffs TCO3 is provided with the Primary circuit Thermal Cutoffs TCO3 pin and second time loop temperature electric fuse TCO3 pin, described second major loop temperature is protected Danger silk TCO1 pin and the first varistor MOV metal electrode are weldingly connected, and described second major loop Thermal Cutoffs TCO2 draws Foot and the second varistor MOV metal electrode are weldingly connected, and described shell is provided above upper cover, described first major loop temperature Electric fuse TCO1 pin and the first major loop Thermal Cutoffs TCO2 pin all extend to housing exterior.

As preferably, described major loop Thermal Cutoffs TCO1 and major loop Thermal Cutoffs TCO2 employing side shell mould temperature Electric fuse or cast Thermal Cutoffs.

As preferably, described major loop Thermal Cutoffs TCO1 and major loop Thermal Cutoffs TCO2 is arranged on varistor MOV both sides or the same side.

Compared with prior art, this utility model has the advantages that

This utility model is respectively provided with a Thermal Cutoffs in varistor both sides, and it is carried out Double-side hot protection, in pressure Before producing high heat after quick resistance failure, especially when varistor both sides focus is uneven or both sides generate heat uneven, can not only be more Quickly utilize varistor abnormal heating amount, shorten Thermal Cutoffs movement time, it is also possible to reduce varistor further The risk of puncture short because unilateral focus is too high, can cut off circuit effectively and rapidly to prevent varistor ignition, reduce fire Calamity risk, makes varistor use safety and reliability.

Accompanying drawing explanation

In order to be illustrated more clearly that this utility model embodiment or technical scheme of the prior art, below will be to embodiment Or the required accompanying drawing used is briefly described in description of the prior art, it should be apparent that, the accompanying drawing in describing below is only It is embodiments more of the present utility model, for those of ordinary skill in the art, in the premise not paying creative work Under, it is also possible to other accompanying drawing is obtained according to these accompanying drawings.

Fig. 1 is the circuit diagram with Double-side hot protection varistor that this utility model provides；

Fig. 2 is the structural representation of embodiment one in this utility model；

Fig. 3 is the structural representation of embodiment two in this utility model.

Wherein: 1. shell；2. varistor MOV；3a. the first varistor MOV metal electrode；3b. second is pressure-sensitive Resistance MOV metal electrode；4. major loop Thermal Cutoffs TCO1；5a. the first major loop Thermal Cutoffs TCO1 pin；5b. Second major loop Thermal Cutoffs TCO1 pin；6. minor loop Thermal Cutoffs TCO3；7a. loop temperature electric fuse for the first time TCO3 pin；7b. second time loop temperature electric fuse TCO3 pin；8. major loop Thermal Cutoffs TCO2；9a. first is main Loop temperature electric fuse TCO2 pin；9b. the second major loop Thermal Cutoffs TCO2 pin；10. heat conduction embedding silica gel；11. Upper cover.

Detailed description of the invention

For the technological means making this utility model realize, creation characteristic, reach purpose and be easy to understand with effect, below In conjunction with detailed description of the invention, this utility model is expanded on further.

Refering to shown in Fig. 1-3, a kind of varistor with Double-side hot protection, including shell 1, described shell 1 is internal to be set It is equipped with varistor MOV2, described varistor MOV2 is provided with the first varistor MOV metal electrode 3a and second pressure-sensitive Resistance MOV metal electrode 3b, described shell 1 is internally provided with heat conduction embedding silica gel 10, and described shell 1 is internal at varistor MOV2 both sides are respectively arranged with major loop Thermal Cutoffs TCO14, minor loop Thermal Cutoffs TCO36 and major loop Temperature protection Silk TCO28, described major loop Thermal Cutoffs TCO14 are by low-melting alloy silk, the first major loop Thermal Cutoffs TCO1 pin Flux disconnected agent and outer protecting shell body thereof of 5a, the second major loop Thermal Cutoffs TCO1 pin 5b, alloy is constituted, described major loop temperature Electric fuse TCO28 is by low-melting alloy silk, the first major loop Thermal Cutoffs TCO2 pin 9a, the second major loop Thermal Cutoffs Flux disconnected agent and outer protecting shell body thereof of TCO2 pin 9b, alloy is constituted, and described minor loop Thermal Cutoffs TCO36 is provided with first Minor loop Thermal Cutoffs TCO3 pin 7a and second time loop temperature electric fuse TCO3 pin 7b, described second major loop temperature Electric fuse TCO1 pin 5b and the first varistor MOV metal electrode 3a is weldingly connected, described second major loop Thermal Cutoffs TCO2 pin 9b and the second varistor MOV metal electrode 3b is weldingly connected, and described shell 1 is provided above upper cover 11, described First major loop Thermal Cutoffs TCO1 pin 5a and the first major loop Thermal Cutoffs TCO2 pin 9a all extends to outside shell 1 Portion, described major loop Thermal Cutoffs TCO14 side is provided with minor loop Thermal Cutoffs TCO36, aging bad at varistor Produce during change one normally closed turn normally opened or by normally opened turn of normally closed signal, for remote alarm or instruction, embedding heat conductive silica gel 10, Described embedding heat conductive silica gel 10 has high thermal conductivity coefficient, is filled in described major loop Thermal Cutoffs TCO14, minor loop temperature Gap between degree electric fuse TCO36 and major loop Thermal Cutoffs TCO28 and described voltage dependent resistor chip, can be quickly by heat Amount is transmitted to described major loop Thermal Cutoffs TCO14, minor loop Thermal Cutoffs from described voltage dependent resistor chip surface In TCO36 and major loop Thermal Cutoffs TCO28；It addition, when described varistor abnormal heating, described alloy-type temperature When degree electric fuse quick fuse is to cut off circuit, volume will expand, and described embedding heat conductive silica gel has certain elasticity, permissible When producing deformation to prevent described alloy-type temperature fuse from fusing, expansion bursts, and Thermal Cutoffs selection temperature range is 100 ~ 135 DEG C, current range is 10A ~ 40 A, and maximum discharge current (8/20 μ s dash current) is 6 ~ 60 kA.

It should be noted that described major loop Thermal Cutoffs TCO14 and major loop Thermal Cutoffs TCO28 employing side shell Type Thermal Cutoffs or cast Thermal Cutoffs.

It should be noted that described major loop Thermal Cutoffs TCO14 and major loop Thermal Cutoffs TCO28 is arranged on pressure Quick resistance MOV2 both sides or the same side.

Of the present utility model ultimate principle and principal character and of the present utility model advantage have more than been shown and described.One's own profession Skilled person will appreciate that of industry, this utility model is not restricted to the described embodiments, described in above-described embodiment and description Principle of the present utility model is simply described, on the premise of without departing from this utility model spirit and scope, this utility model is also Have various changes and modifications, in the range of these changes and improvements both fall within claimed this utility model.This utility model Claimed scope is defined by appending claims and equivalent thereof.

Claims (3)

1. a varistor with Double-side hot protection, it is characterised in that: including shell (1), described shell (1) is internal to be arranged There is varistor MOV (2), described varistor MOV (2) is provided with the first varistor MOV metal electrode (3a) and second Varistor MOV metal electrode (3b), described shell (1) is internally provided with heat conduction embedding silica gel (10), and described shell (1) is internal Major loop Thermal Cutoffs TCO1 (4), minor loop Thermal Cutoffs TCO3 (6) it is respectively arranged with in varistor MOV (2) both sides With major loop Thermal Cutoffs TCO2 (8), described major loop Thermal Cutoffs TCO1 (4) by low-melting alloy silk, first lead back Flux disconnected agent and outer in road Thermal Cutoffs TCO1 pin (5a), the second major loop Thermal Cutoffs TCO1 pin (5b), alloy Protective case body is constituted, and described major loop Thermal Cutoffs TCO2 (8) is by low-melting alloy silk, the first major loop Thermal Cutoffs TCO2 Flux disconnected agent and outer protecting shell body thereof of pin (9a), the second major loop Thermal Cutoffs TCO2 pin (9b), alloy is constituted, described time Loop temperature electric fuse TCO3 pin (7a) and second time loop temperature for the first time it is provided with on loop temperature electric fuse TCO3 (6) Electric fuse TCO3 pin (7b), described second major loop Thermal Cutoffs TCO1 pin (5b) and the first varistor MOV metal Electrode (3a) is weldingly connected, described second major loop Thermal Cutoffs TCO2 pin (9b) and the second varistor MOV metal electricity (3b) is weldingly connected in pole, and described shell (1) is provided above upper cover (11), described first major loop Thermal Cutoffs TCO1 pin (5a) it is outside that He the first major loop Thermal Cutoffs TCO2 pin (9a) all extends to shell (1).

A kind of varistor with Double-side hot protection the most according to claim 1, it is characterised in that: described major loop temperature Spend electric fuse TCO1 (4) and major loop Thermal Cutoffs TCO2 (8) employing side shell mould Thermal Cutoffs or cast Thermal Cutoffs.

A kind of varistor with Double-side hot protection the most according to claim 1, it is characterised in that: described major loop temperature Degree electric fuse TCO1 (4) and major loop Thermal Cutoffs TCO2 (8) are arranged on varistor MOV (2) both sides or the same side.