JPS5951503A - Thermistor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a thermistor that detects the temperature of food inside the pot through the bottom of the pot when cooking in a pot. Temperature detection has been carried out by mechanically bringing a thermocouple 2 into contact with the pot bottom 1 and detecting the thermoelectromotive force of the thermocouple 2, as shown in FIG.

At this time, the thermocouple 2 was fixed to the support container 3 in order to bring the thermocouple 2 into strong mechanical contact with the pot bottom 1. However, there was a drawback in that thermoelectromotive force could normally only be produced at a small value. For example, alumel-chromel thermocouples have excellent heat resistance (500 to 10,001:); 1. They are inexpensive, but have a heat resistance of ~40μ/℃? Only IU force is generated. Copper-constancouple thermocouples and platinum-white 6i-rhodium thermocouples not only cannot obtain a thermoelectromotive force of (30 to 60) μV/TL, but also have low heat resistance (copper-constancouple thermocouples). The drawback was that it was expensive (platinum-platinum/rhodium thermocouple). Various other thermocouples exist, but all of them have the drawbacks mentioned above. When controlling the amount of heat generated by a heat source by electrically detecting a small thermoelectromotive force as described above, a large amount of electrical amplification must be performed, which increases the cost. There were also disadvantages such as the need for complex electrical circuits.

On the other hand, when temperature is detected using a thermistor instead of the above thermocouple, the rate of change in resistance value with respect to temperature is (1 to 7%/
℃) can be obtained. Therefore, it has the advantage of not requiring a complicated electric circuit and being much cheaper. In this case, the thermistor element t is made as small as possible and one with a small heat capacity is selected. This is because miniaturization allows for faster thermal response. When taking out the internal lead wire from such a small thermistor element, such as a thin film thermistor chip, it is usually necessary to use a heat-resistant, corrosion-resistant thin metal wire,
For example, gold wire, white wire, etc. with a diameter of 50 to 200 μφ are selected. Because this internal lead wire is thin and difficult to handle, and because it is expensive, an external lead wire is further connected to this internal lead wire, and the resistance value of the thermistor element is adjusted through this external lead wire. , and therefore the temperature is detected. For the outer Er1SIJ- lead wire, Sderens wire, nickel helix, iron-chromium wire, etc. are selected in consideration of ease of connection with the inner lead wire, reliability, heat resistance, and corrosion resistance. However, in this case, the connection strength between the internal lead wire and the thermistor element is tens of tens of tens
Because it is small, only a few hundred meters, a slight stress may be applied during use, or in extreme cases, internal damage may occur. j′
, depending on the weight of the ls lead wire, it is several hundred to several thousand ratio 1
There was a drawback that the wire was likely to be disconnected from the connection after the connection was completed.

OBJECTS OF THE INVENTION The present invention i1--provides a horn I (erasing/ζ buzzer star) which overcomes the drawbacks of the prior art.

Structure of the Invention The present invention (1) is a thermistor in which a thin film thermistor element is fixed to a supporting container and internal lead wires and external lead wires are taken out, and a plurality of small holes are provided at least at the end of the supporting container. In addition, an insulating support plate having a layer (connection layer) that can be used for soldering is provided around the small hole so as to be electrically isolated from each other, and This configuration connects an internal lead wire and an external lead wire.

DESCRIPTION OF THE EMBODIMENTS In one embodiment of the present invention, as shown schematically in FIG. A thermistor with an external lead wire 6 taken out has a plurality of small holes 7 at least at the end of the support container 3, and the areas around the small holes are soldered or soldered so as to be electrically isolated from each other. An insulating support plate 9 having a layer (connection layer) 8 made of material is provided, and the internal lead wire 6 and the external lead wire 6 are connected via the insulating support plate 9.

The thin film thermistor element 4 is constructed by forming a temperature sensitive resistor film and an electrode film on one surface of an insulating substrate.

This thin film thermistor element 4 is fixed so that the other surface of the insulating substrate and the surface of the support container 3 face each other.

This fixation can be done using inorganic or organic adhesive, solder, or
This is done via a fixing layer 1o such as brazing.

The internal lead wire 6 is taken out of the insulating support plate 9 through a small hole 7. The internal lead wire 5 and the external lead wire 6 are connected by solder or brazing material 11 at the connection layer 8 portion. The insulating support plate 9 is fixed to the support container 3 by claws 12 provided on the support container 3. Therefore, thermistor element 4
No stress is applied to the connection portion between and the internal lead wire 6. Is the tensile strength of the connection between the internal lead wire 5 and the external lead wire 6 still greater than 2 Kf? ! ), which was sufficient for practical use.

As described above, stress is not substantially applied to each connection part of the thermistor of this embodiment, or mechanical ((practical)
2. Since it has sufficient strength, disconnection will not occur.

Note that the connection layer 8 includes Ag, Ag-Pd, Au, 'A
u-Pt.

Cu on thick film electrode film such as PT, Ct, Ni etc.

Vapor deposited film laminated with silver, Ag, etc., or W.

One or more metallized films selected from the group of Mo, Ni, and Mn are used. Thick film electrode films and vapor deposited films can be easily soldered, but the heat resistance temperature is (150 to 3
00) It has the disadvantage of being low at below ℃. This is thought to be because Au, Ag, etc. gradually diffuse into the solder, reducing adhesive strength. For the same reason, brazing cannot be used for thin films. However, a brazing material can be used for the metallized film,
Moreover, its heat resistance temperature is (300 to eoo)°C.

In fact, when silver brazing material was applied to W metallized film (20 to 60
)''//cni tensile strength was obtained.

Therefore, thermistors can be used at high temperatures.

Ru. When the thermistor is brought into contact with the pot bottom 1 to detect the temperature inside the pot as described above, the metallized film is light and heavy since the cooking temperature ranges from 50 to 350°C.

Further, the insulating support plate 9 is made of alumina, mullite, beryllia, or the like.

Further, in the above description, a configuration was shown in which the insulating support plate 9 was fixed with the claws 12, but in this case, since it is fixed mechanically, a slight gap occurs. As a result, steam from oil, oil, etc.
In a high-temperature air atmosphere containing fine droplets, steam, fine droplets, etc. may enter the support container 3 and stain the thin film thermistor element 4. Since this dirt causes the fluctuation of the thermistor element 4 to decrease by .eta., this kind of dirt must be removed. In such a case, it is preferable to form a metallized film 13 as described above on the peripheral part 98 of the insulating support plate 9, and to print this metallized film 13 and the peripheral part 3A of the support container 30 in a roll. This configuration is shown in FIG. The peripheral part 38 of the support container 3 and the peripheral part Ffli 9 of the insulating support plate 9
It is fixed to A by brazing material 14. As a result, the support container 3 and the insulating support plate 9 are integrated, and not only are they mechanically and firmly connected, but also their peripheral parts 3
A, 9A, steaming, minute droplets, etc. will not enter the inside of the support container 3. At this time, the small hole 7 is set to low) 11
sealed by. In this way, the structure shown in FIG.
The inside of the film thermistor element 4 is completely airtight.
will not become dirty. .

Effects of the Invention The present invention (:11) A thermistor in which a thin film thermistor element is identified in a support J-1 container and an internal lead heald and an external lead wire are taken out, which has a plurality of small holes at least at the end of the support container. In addition, an insulating support plate having a layer (connection layer) made of semi-conductor or brazing material is provided around the small hole so as to be electrically isolated from each other, and this insulating support plate is Because the structure connects the internal IJ lead wire and the external lead wire through the thermistor, there is virtually no stress applied to each connection part of the thermistor, or the wire has sufficient mechanical strength for practical use, so disconnection does not occur. It also has excellent thermal properties, and the internal thin-film thermistor does not become contaminated by the external atmosphere.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the configuration of a conventional example, and FIG. FIG. 3 is a cross-sectional view showing the configuration of an embodiment according to the present invention. 6° 3...Support container, 3A...Support container 30 periphery, 4...Thin film thermistor element, 6...
Internal lead wire, 6... External lead wire, 7...
... Small hole, 8 ... Layer that can be soldered or brazed (connection layer), 9 ... Insulating support plate, 9A ...
... Peripheral part of insulating support plate 9, 10 ... Fixed layer, 11 ... Low moon, 12 ... Nail, 13
...metalized film, 14... brazing material. Name of agent: Patent attorney Toshio Nakao and one other person. H≦12-

Claims (3)

[Claims] (1) A thermistor formed by fixing a thin film thermistor element to a support container and taking out an internal lead wire and an external lead wire, which has a plurality of small holes at least at the end of the support container, and around the small holes, An insulating support plate having a layer (connection layer) that can be soldered or brazed so as to be electrically isolated from each other is provided, and the internal saw 1' wire and the external lead wire are connected via this insulating support plate. thermistor. (2) The thermistor according to claim 1, wherein the connection layer is a metalized film of one or more types selected from the group of W, Mo, Ni, and Mn. (3) W, Mo, Ni on the periphery of the insulating support plate
, Mn, forming one or more metallized films. Mister.