KR200250373Y1 - Close-adhesion type thin-film temperature sensor - Google Patents

Abstract

The present invention relates to a temperature sensor having a structure that is easy to measure the surface temperature. Specifically, the sensor element is embedded in the flexible sheet-type insulating protective layer so that the wide surface of the sensor element is arranged in parallel with the surface portion of the measuring portion, and the sheet-like conductive polymer layer is located between the contact surface between the insulating material and the measuring object. The present invention relates to a surface-contact type thin temperature sensor having a structure in which electrodes are connected to the outside.

According to the present invention, since the temperature sensor is manufactured in the form of a sheet and has overall flexibility, it is not disturbed by the surface shape of the measuring object, and by additionally configuring a conductive polymer layer having excellent thermal conductivity on top of the measurement material under the insulating protective layer. A quick and accurate temperature sensor can be obtained.

Description

CLOSE-ADHESION TYPE THIN-FILM TEMPERATURE SENSOR}

The temperature sensor is a sensor element that mainly measures the internal temperature by submerging in a given space or material, and is currently widely used in air conditioners, refrigerators, automobiles, and the like.

A conventional temperature sensor is shown in FIG. Fig. 1A shows a schematic view of a conventional temperature sensor, Fig. 1B shows a cross section of an epoxy protective layer, and Fig. 1C shows a cross section of an outer cap layer. The conventional temperature sensor connects the wire 14 to the sensor element 11, specifically, a platinum element or a negative temperature coefficient (NTC) thermistor element, and forms the protective layer 13 on the outside of the element by epoxy, glass, or the like. Then, most of the so-called cylindrical probe-type temperature sensors, which are again built in a protective cap 16 or the like filled with silicone resin and kept airtight from the outside. In this sensor structure, as shown in FIG. 1B, the diameter of the epoxy protective layer is larger than that of the sensor element, and the cap is protected by the cap again. As shown in FIG. In addition, such a probe-type temperature sensor includes the following problems when measuring the temperature when the part to be measured is the surface.

(A) It is difficult to transmit temperature due to the small area in contact with the surface.

(B) The sensor's response time is long because the sensor element is embedded in epoxy, silicone resin in the protective cap, and is isolated from the outside.

(C) In particular, when measuring the temperature of the flat surface, the probe-type sensor may fall off the measurement surface. In this case, the temperature transmitted through the air must be measured. Therefore, the accuracy is inferior. none.

On the other hand, when measuring the human body temperature, in the past, a method of measuring the temperature by putting a probe-type temperature sensor in the armpit or holding it in the mouth. Because children tend to avoid foreign objects, which makes measurement difficult. Recently, non-contact temperature sensors using internal temperature of the ear have been used in pediatric hospitals, but non-contact temperature sensors have a limited measurement area and complex structure compared to contact types. It is expensive and difficult to use for general purpose.

An object of the present invention is to provide a temperature sensor that accurately measures the temperature of the surface portion.

It is another object of the present invention to provide a temperature sensor having a large contact area and reaching thermal equilibrium in a short time.

Another object of the present invention is to provide a temperature sensor with a small thermal gradient in the wiring.

1 conventional temperature sensor

1a structure of a conventional temperature sensor

Figure 1b cut surface of the epoxy protective layer

Fig. 1c Cut surface of the outer protective cap

2 is a structure of the surface-contact type temperature sensor module

3 Another example of the present invention

Figure 4 Temperature sensor using the surface-contact temperature sensor module

4a, 4b appearance of the temperature sensor module with the built-in temperature sensor element

Figure 4c wires connecting the temperature sensor module and the display circuit portion

Fig. 4d Completed sensor with integrated temperature sensor module and connecting wire

Explanation of symbols for main parts of the drawings

11: temperature sensor element

12: soldering part

13: epoxy protective layer

14: lead wire

15: soldering lead wire

16: outer protective cap

21: upper insulating protective layer

22, 32: internal wiring electrode

23: lower insulating protective layer

24: thermally conductive polymer layer

25: measuring object

2 shows a first embodiment of the present invention. In the temperature sensor module of the present invention, the sensor element 11 is positioned between the flexible insulating sheet protection layers 21 and 23 in which the internal wiring electrode 22 is formed, The contact surface side has a structure in which the thermally conductive polymer sheet layer 24 is formed. The characteristic of the present invention is that the entire temperature sensor is designed to have a thin sheet-like structure as shown in FIG. 2 and further comprises a conductive polymer layer in contact with the measurement material. By having such a structure, the contact area with the part to be measured can be increased and thermal equilibrium can be reached within a short time, so that accurate temperature measurement is possible.

Hereinafter, the configuration of each part will be described in more detail.

First, the temperature sensor element 11 functions to convert heat sensed from the measurement object 25 into an electrical signal, and its shape is embedded so that the wide surface of the element is configured in parallel with the surface portion of the measurement portion. . As the temperature sensor element 11, a platinum temperature sensor, a double-sided electrode type negative temperature coefficient thermistor, a thermocouple element, or the like may be used. Among them, Negative Temperature Coefficient (NTC) thermistors have the advantage of being thinner than platinum temperature sensors and thermocouple sensor elements. That is, thermocouple type devices are difficult to manufacture in a thick film type because of the wire shape, while in the case of a negative temperature coefficient thermistor, it is very easy to manufacture a thin film type or a thin film type through a thick film process.

The manufacturing method of such a stacked negative temperature coefficient thermistor element is described in detail in the applicant's utility model application No. 2000-14797 (single plate surface mount chip component) and patent application No. 2000-28304 (negative temperature coefficient element using spinel ferrite). Described.

The internal wiring electrode 22 serves to connect signals from the temperature sensor element and is designed in the insulating protective layers 21 and 23 on both sides of the element 11. It should be noted that the upper wiring electrode is also designed on the back surface of the upper insulating protective layer 21 of FIG.

The internal wiring electrode 22 is generally made of a material having high electrical conductivity, such as copper, aluminum, silver, and gold. This internal wiring electrode can be formed in the insulating protective layer by a method such as thick film printing, lamination and etching. On the right side of FIG. 2, a portion of the electrode is exposed to the outside. The electrode portion exposed to the outside is coated with a single layer or a multi-layer structure using nickel, gold, solder, or the like to improve durability of the electrode portion. It is also possible to facilitate solder bonding.

The upper and lower insulation protection layers 21 and 23 are insulation protection layers of the device, and are made of one or a variety of resins such as vinyl, epoxy, phenol, Teflon, and silicon. The lower protective layer has a structure of a composite layer with a conductive polymer layer, which will be described later, so that the surface of the measuring object and the sensor achieve thermal equilibrium in a short time, and the upper insulating layer suppresses heat transfer between the sensor and the outside air. To stabilize the thermal equilibrium. In order to maximize the above effects, the upper insulating layer needs to have a certain thickness for electrical insulation and insulation, and the lower insulating layer preferably has a minimum thickness for electrical insulation.

A thermally conductive polymer layer 24 is formed at the bottom of the lower protective layer 21. This effectively transfers heat from the measuring object to the sensor element. The thermally conductive polymer layer 24 preferably has a minimum thickness for thermal conductivity and structural durability. As the thermally conductive polymer layer 24, a silicon rubber in which carbon is filled with a filler is used.

At this time, by applying a gel-like adhesive material to the lower surface of the conductive polymer layer 24 to produce a temperature sensor it is easy to attach and detach on the surface of the measuring body. When maintaining the adhesive state for a long time or when there are a lot of movements, such as measuring the body temperature of children, using the temperature sensor of the present invention coated with the adhesive material can be produced a temperature sensor that is not easily removable.

On the other hand, if the difference between the temperature of the temperature sensor element and the temperature of the ambient atmosphere is large, heat dissipation to the conductor wiring may occur, which may be different from the actual temperature of the measuring body. In order to solve this problem, it is necessary to lower the thermal conductivity of the conductor wiring. For this purpose, if the cross-sectional area and thickness of the conductor are reduced or the length of the conductor wiring is increased, the temperature gradient in the wiring is small, and heat dissipation by the wiring can be ignored.

3 illustrates a configuration of a temperature sensor module in which a shape of a conductor wiring, which is another embodiment of the present invention, is changed. Compared with the first embodiment of FIG. 2, the components of the temperature sensor module have the same configuration, but the shape of the lead wire connecting electrode is different from that of the zigzag shape 32. The thin temperature sensor module having such a structure has an advantage in that the temperature gradient in the wiring is reduced so that a stable value can be read out during temperature measurement.

Figure 4 shows a schematic diagram of a temperature sensor using a temperature sensor module of the present invention. The sensor element 11 is positioned between the insulating protective layers 21 and 23 in which the conductor wirings 22 and 32 are embedded as shown in FIG. 2 or 3, and the thermally conductive polymer layer 24 is disposed on the lower contact surface. Positioning and then integrating by a method such as thermocompression, the temperature sensor module as shown in Figure 4a or 4b is completed. Figure 4c shows a wire connecting the sensor and the display circuit portion, when integrated with the temperature sensor module, the temperature sensor as shown in Figure 4d is completed.

According to the present invention, since the temperature sensor has a thin structure, the temperature sensor may be built in a very small space, and the temperature sensor may be manufactured without affecting the shape of the surface due to its flexibility.

The temperature sensor according to the present invention is manufactured by a simple process, and can be mass-produced by using a sheet-like material, thereby providing a low-cost supply.

Claims (3)

Sheet-type insulating protective layers 21 and 23 having internal electrodes 22 for wiring, Thin negative temperature coefficient thermistor sensor element 11 embedded between the upper and lower insulating protective layers, A sheet-shaped thermally conductive polymer layer 24 formed on the contact surface with the measurement material, Surface-tight, thin temperature sensor consisting of an electric wire for connection from the internal electrode for wiring to the measuring instrument The method of claim 1, Surface-contact type thin temperature sensor characterized in that the internal electrode is formed in a zigzag shape The method according to claim 1 or 2, Surface-contact thin temperature sensor, characterized in that the gel adhesive material is applied to the bottom of the thermal conductive polymer layer