JPS60170201A - Temperature sensor - 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] [Technical field to which the invention pertains] The present invention relates to a temperature sensor that detects changes in the temperature around a resistor according to changes in the electrical resistance value of the resistor, especially for fire prevention. This invention relates to a temperature sensor that can be used in an alarm.

[Prior art and its points of interest]

Generally, the warm sensors used in fire alarms are vime,
It uses the thermal expansion of metal materials and fluids, such as the 6-ru type and tongue type. This type of temperature sensor has poor responsiveness because its temperature-sensing element has a large heat capacity, and it takes from several seconds to several minutes to operate after sensing heat (fire outbreak). Therefore, by the time a fire alarm is issued by the temperature sensor, it is often too late for fire extinguishing and evacuation efforts. Furthermore, since this type of temperature sensor has moving parts, there are also problems with operational reliability and accuracy.

[Purpose of the invention]

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, it is an object of the present invention to provide a temperature sensor with good responsiveness, reliable operation, and high accuracy.

[Key points of the invention]

According to the present invention, this object is achieved by providing a temperature sensor of the type mentioned at the outset, in which a thin film resistor made of a metal having a large temperature coefficient of resistance and being resistant to corrosion is provided on the surface of a flexible insulating film having heat and corrosion resistance. This is achieved by forming.

[Implementation of the invention-Example]

K.Explain. Identical parts in each drawing are designated by the same reference numerals.

1 and 2 are a plan view and a side view, respectively, of a temperature sensor according to the present invention, and 1 is a flexible insulating film with excellent heat resistance and corrosion resistance, for example, a thickness of 50 μm.
2 is a polyimide film formed on the surface of this insulating film, and 2 is a thin film resistor made of a metal with a large resistance temperature coefficient and excellent corrosion resistance, for example, a platinum layer with a thickness of 500 A produced by high frequency sputtering method. and
Reference numeral 3 denotes an M pole consisting of a gold layer having a thickness of 0.5 μm, which was similarly produced by high-frequency sputtering at both ends of the thin film resistor 2.

This temperature sensor has resistance-temperature characteristics as shown in FIG. In Figure 3, the horizontal axis is temperature (T (℃))
The vertical axis is the resistance value (R(T°C)/R(3o°C):) based on the resistance value at 30°C. The temperature coefficient of resistance of this temperature sensor at 30°C is 0. ]5%/°C. Although the resistance value is more than twice the value calculated from the bulk resistivity, film thickness, and shape, if the thin film formation conditions, such as sputtering conditions, are fixed, the resistance temperature coefficient and resistance value can be obtained with good reproducibility. Figure 4 shows the relationship between the resistance value (Ω) and the temperature coefficient of resistance (%/''C) at 30°C obtained by setting the sputtering input to 50 W and 100 W for sensors of the same shape. If the variation in value is suppressed to ±10, the variation in temperature coefficient of resistance will be ±10.
It is within 0.0015%/°C, which is sufficient for practical use.

Since the resistor according to the present invention is an extremely thin film, it has a small heat capacity and responds sensitively to ambient temperature. Even if one sensor is wrapped around a rod with a diameter of 10 mm, the layer of the thin film resistor 1 will not peel off from the insulating film.
No abnormality occurs in the resistance value. Therefore, it can be used in various forms as required.

FIG. 5 shows different embodiments of the temperature sensor according to the invention. In this case, the electrodes 3 at both ends of the thin film resistor 2 are formed to cover the ends of the thin film resistor 2, and furthermore, the entire exposed surface of the thin film resistor 2 is covered with a protective coating 4 having excellent corrosion resistance. . Therefore, this sensor can withstand highly corrosive atmospheres.

FIG. 6 shows yet another embodiment, in which the thin film resistor 2
are formed in a U-shape, and the electrodes 3 are located on the same side, which is advantageous for wiring. Furthermore, if necessary, the C thin film resistor 2 can be meandered a plurality of times to provide a desired resistance value.

Note that as the material for the thin film resistor 2, gold, titanium, or the like can also be used in addition to platinum in the above-mentioned example.

In addition to the above-mentioned polyimide, polyoxybenzoyl, polyamideimide, polyether ether, ketone, polyphenylene sulfide, polyphenylene oxide, polysulfone, or polytetrafluoroethylene may be used as the material for the flexible insulating film. I can do it.

〔Effect of the invention〕 .

The temperature sensor according to the invention has the following advantages.

Since the heat capacity of the mm film resistor is very small, it immediately responds to the ambient temperature (within a few seconds) and has very good responsiveness.

(2) Since the temperature-sensitive element, that is, the thin film resistor is formed on an insulating film with excellent heat resistance and corrosion resistance, it can be used for a long period of time even in harsh environments.

(3) Since it has no moving parts, it has high operational reliability and accuracy, and can be used in various temperature detection sensors such as for air conditioning as well as fire alarms.

[Brief explanation of the drawing]

1 and 2 are a plan view and a side view, respectively, of a temperature sensor according to the present invention, FIG. 3 is a diagram showing the resistance-temperature characteristics of the temperature sensor according to the present invention, and FIG. 4 is a diagram showing the resistance-temperature characteristics of the temperature sensor according to the present invention. Figure 5 is a diagram showing the relationship between the resistance value and the temperature coefficient of resistance at 30°C with the sputtering input of temperature sensors of the same shape as parameters based on the present invention; FIG. 6 is a plan view of still another embodiment of the invention. 1... Flexible insulating film, 2... Thin film resistor,
3... Electrode, 4... Protective film. Figure 1 Figure 2 Lagoon Degree T (0C) Figure 4 Figure 5

Claims (1)

[Scope of Claims] ]) A temperature sensor characterized in that a thin film resistor made of a metal having a large temperature coefficient of resistance and corrosion resistance is formed on the surface of a flexible insulating film having heat resistance and corrosion resistance. 2. The temperature sensor according to claim 1, wherein the material of the film resistor is platinum, gold, or titanium. 3) In the temperature sensor according to claim 1 or 2, a flexible insulating film 7
A temperature sensor characterized in that it is made of polyphenylene oxide, polyphenylene oxide, polysulfone, or polytetrafluoroethylene. 4) The temperature sensor according to any one of claims 1 to 3, characterized in that the thin film resistor is formed on the surface of a flexible insulating film by high-frequency sputtering. sensor. 5) A temperature sensor according to any one of claims 1 to 6, characterized in that the thin film resistor is covered with a corrosion-resistant protective coating.