CN1945762A

CN1945762A - NTC thermosensitive resistor for automobile air conditioner and its preparing method

Info

Publication number: CN1945762A
Application number: CN 200610122810
Authority: CN
Inventors: 莫海声
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-10-17
Filing date: 2006-10-17
Publication date: 2007-04-11

Abstract

This invention discloses a NTC thermistor used in car air condition and its preparation method, in which, the thermistor is composed of a chip, metal electrodes coated on both sides of the chip, a leading out wire welded on the surface of the metal electrode and an insulation layer covering the outer surface characterizing that the main composition of the chip material includes: MnO2 40-60%, Co2O3 40-50%, Ni2O1-6% and Fe2O3 1-4%.

Description

A kind of NTC themistor that is applied to air conditioning for automobiles and preparation method thereof

Technical field

The present invention relates to the high-purity transition metal oxide is the electronic devices and components and the manufacture method thereof of primary raw material, specifically is a kind of NTC themistor that is applied to air conditioning for automobiles and preparation method thereof.

Background technology

NTC is the abbreviation of Negative Temperature Coefficient, and the meaning is the temperature coefficient of bearing, very big semi-conducting material or the components and parts of general reference negative temperature coefficient, and so-called NTC themistor is exactly a negative temperature coefficient thermistor.NTC themistor be a kind of be the semiconductive ceramic element that main material is made with the high-purity transition metal oxide, it is to be main material with metal oxides such as manganese, cobalt, nickel and copper, adopts the ceramic process manufacturing to form.These metal oxide materials all have semiconductor property because on electrically conducting manner semi-conducting materials such as all fours germanium, silicon.When temperature was hanged down, the charge carrier of these oxide materials (electronics and hole) number was few, so its resistance value is higher; Along with the rising of temperature, the charge carrier number increases, so resistance value reduces.Therefore it has the characteristic of resistance value respective change with variation of temperature, promptly measures under the power characteristic that resistance value descends with the rising of temperature certain.NTC themistor excursion at room temperature is at 100～1000000 ohm, temperature coefficient-2%～-6.5%.Utilize this characteristic, NTC themistor can be widely used in occasions such as temperature survey, temperature-compensating, inhibition surge current.

The NTC thermistor is installed near the automobile air-conditioning evaporator fin ambient temperature around surveying.When the temperature value that records is lower than a certain set point (near 0 ℃), relay disconnects, and compressor shuts down; When the temperature value that records is higher than another set point (usually above last temperature value), the relay adhesive, compressor starts again, can prevent that like this air-conditioning duct from freezing.

Summary of the invention

The present invention proposes a kind of NTC themistor that is applied to air conditioning for automobiles and preparation method thereof, the stable performance of this thermistor, but long-term work.

For achieving the above object, the technical solution adopted in the present invention is as follows: a kind of NTC themistor that is applied to air conditioning for automobiles, it is by chip and be coated in the metal electrode on chip two sides, the lead-out wire that is welded on surface of metal electrode and coating lid insulating barrier outside, it is characterized in that the main component of described chip material consists of:

Manganese dioxide 40%～60%;

Cobalt sesquioxide 40%～50%;

Nickel protoxide 1%～6%;

Di-iron trioxide 1%～4%.

The metal electrode of the coated on both sides of described chip is a silver electrode.

Described chip raw material are the electron level metal oxide.

A kind of preparation method who is applied to the NTC themistor of air conditioning for automobiles is characterized in that this preparation method's step is as follows:

A. respectively with the weighing in proportion of several raw material, add the deionized water ball milling;

B. with mixture under 100 ℃ of conditions the oven dry after, place Muffle furnace to carry out 950 ℃ calcining;

C. be pressed into the cylinder of definite shape with isostatic pressing machine, in 1200 ℃ high temperature furnace, sinter fine and close ceramic body into;

D. cut into the thin slice of 0.40mm with the high accuracy slicing machine,, be divided into 1.0 * 1.0 little chips with the high accuracy scribing machine again in its coated on both sides silver electrode;

E. lead-out wire is welded on the chip two sides respectively, coat one deck epoxy resin at last, promptly can be made into the NTC themistor that is applied to air conditioning for automobiles.

This NTC themistor resistance value and B value precision height, high conformity, and have good insulation performance sealing and anti-mechanical collision, warping resistance ability.

Embodiment

The invention will be further described below in conjunction with embodiment.

Be the epoxy packages NTC themistor that a model is HX-MF52AT152F390F below, the raw material of its chip material consist of:

Manganese dioxide 100 grams;

Cobalt sesquioxide 90 grams;

Nickel protoxide 6 grams;

Di-iron trioxide 4 grams.

Its preparation method is:

The first step with the weighing in proportion of several raw material, is added the deionized water ball milling respectively;

Second step after oven dry under 100 ℃ of conditions, placed Muffle furnace to carry out 950 ℃ calcining mixture;

The 3rd goes on foot the cylinder that is pressed into definite shape with isostatic pressing machine, sinters fine and close ceramic body in 1200 ℃ high temperature furnace into;

The 4th goes on foot the thin slice that cuts into 0.40mm with the high accuracy slicing machine, again in its coated on both sides silver electrode, is divided into 1.0 * 1.0 little chips with the high accuracy scribing machine;

The 5th step was welded lead-out wire respectively with the chip two sides, coated one deck epoxy resin at last, promptly can be made into the NTC themistor that is applied to air conditioning for automobiles.

The characteristics of this thermal resistor are:

1. resistance value and B value precision height, high conformity;

2. stable performance, but long-term work;

3. good insulated enclosure and anti-mechanical collision, warping resistance ability.

The scope of application of this thermal resistor is:

Be mainly used in air conditioning for automobiles.

Claims

1, a kind of NTC themistor that is applied to air conditioning for automobiles, it is by chip and be coated in the metal electrode on chip two sides, the lead-out wire that is welded on surface of metal electrode and coating lid insulating barrier outside, it is characterized in that the main component of described chip material consists of:

Manganese dioxide 40%～60%;

Cobalt sesquioxide 40%～50%;

Nickel protoxide 1%～6%;

Di-iron trioxide 1%～4%.

2, NTC themistor according to claim 1, the metal electrode that it is characterized in that the coated on both sides of described chip is a silver electrode.

3, NTC themistor according to claim 1 and 2 is characterized in that described chip raw material are the electron level metal oxide.

4, a kind of preparation method who is applied to the NTC themistor of air conditioning for automobiles is characterized in that this preparation method's step is as follows: