JPS61147124A - Sheet type heat sensitive probe - Google Patents

Abstract

PURPOSE:To make possible the mass production of products having high quality at a low cost by the simple constitution consisting in forming conductive patterns by printing on the surface side of films, press-welding thermistor tips thereto and combining suitably the conductive patterns and the resistance value of the conductive paterns and the thermistor tips. CONSTITUTION:Terminal window holes 52 are formed along both sides of a belt-like film 50 at a specified pitch and the conductive patterns 54 are formed by silk printing on one surface thereof. Part or the entire part of the patterns 54 are formed of a material having relatively high resistivity and the resistance value from the press contact point of the termistor tips 56 up to the exposing point of the holes 26a, 26b is selected to meet the resistance value of the tips 56. The tips 56 are the positioned to the top end parts of the patterns 54 and are adhered thereto. Another film 50 mad into exactly the same constitution is further superposed and positioned on the film 50 in such a manner that the printed surface of the patterns 54 face each other. Two sheets of the superposed films 50 are thereafter thermocompression-bonded. The laminated film is cut along dotted lines (b) and perforations 14 are formed, by which the probes are completed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) This invention relates to a temperature-sensitive probe for an electronic thermometer, and in particular,
This invention relates to a sheet-shaped probe intended to be disposable every time body temperature is measured.

(Summary of the invention) This invention includes a thermistor chip and conductive means for external connection between an insulating laminate film, and a conductive pattern is printed and formed on the bonding surface side of the film. The structure is such that the thermistor chip is electrically connected by press-welding the thermistor chip to this, and the conductive pattern is a resistor made of a material with relatively high resistivity, and the resistance value of the conductive pattern and the resistance value of the thermistor chip are By appropriately combining them, it is possible to eliminate variations between products, improve productivity, and reduce costs.

(Prior art and its problems) A typical example of this type of sheet-type temperature-sensitive probe is Patent Application Publication No. 500191 of 1982 (based on a PCT application), which has also been put into practical use. Further, an electronic thermometer using a sheet-type temperature-sensitive probe is disclosed in, for example, Patent Application Publication No. 54422 of 1981.

In the conventional sheet-type temperature-sensitive probe described in the above publication, two metal wires are stretched in parallel between two insulating sheets, and the two electrode surfaces of the thermistor chip are soldered to both wires. , which is sandwiched between both sheets. In addition, the tip end where the thermistor chip is installed is later covered with a plastic film, covering the cut surface of the wire to insulate it and making it liquid-tight. This allows the tip of the probe to be inserted into a person's mouth without any problems. Further, a terminal window hole is formed on the proximal end side of the probe, and the wire is exposed within the hole. This exposed wire contacts the terminals of the electronic thermometer.

In the conventional structure described above, two insulating sheets are roughly wrapped in a plastic film, so the number of parts is large and the assembly process is very troublesome. Furthermore, there are multiple steps for stretching and cutting wires on the sheet. Furthermore, soldering the wire and the thermistor chip is a very troublesome task because the chip is minute.

In this respect, conventional products have extremely low productivity, which is a major limiting factor in cost reduction through mass production.

In addition, in the conventional type, as a countermeasure against variations in the resistance value of the thermistor chips, two thermistor chips are connected in series between the above wires, and the resistance values of the two chips are appropriately combined, so that the combined value of the resistance is uniform. I'm trying to get it all together. This measure makes productivity even worse.

In addition, a metal plate is used as an intermediate connector to connect chips in series, but this metal plate increases the heat capacity of the chips and their surroundings, causing a longer body temperature measurement time.

(Object of the Invention) This invention was made in view of the above-mentioned conventional problems, and its object is to provide a simple configuration with a small number of parts,
An object of the present invention is to provide a highly productive sheet-type temperature-sensitive probe that enables mass production of high-quality products at low cost.

(Structure and Effect of the Invention) Therefore, the present invention has a basic structure in which a thermistor chip is sandwiched between two insulating films and laminated, and two conductive patterns are printed in advance on one or both bonding surfaces of the films. The two electrode surfaces of the thermistor chip were brought into pressure contact with the conductive pattern, and part of the conductive pattern was exposed in the terminal window hole formed in the film.

Further, in the present invention, part or all of the conductive pattern is formed of a material with relatively high resistivity, and the resistance value from the pressure contact point of the thermistor chip to the exposed point at the terminal window hole is determined by the resistance value of the thermistor chip. The selection was made in accordance with the value.

The thermistor chip enclosed in the laminated film is
It is electrically connected to a conductive pattern printed on the inner surface of the film, and is electrically connected to the conductive pattern in the terminal window hole.

Furthermore, variations in the resistance value of the thermistor chip are compensated for by the resistance value of the conductive pattern, and the resistance value seen from the terminal portion of the conductive pattern is made uniform.

The sheet-type temperature-sensitive probe according to the present invention has a thermistor chip sandwiched between two laminated films, and the S-electrode pattern printed on the inner surface of the film is used as wiring for external connection, so the number of parts is small. It does not involve troublesome processes such as wiring or soldering, and can be hung on the ceiling very easily.The simple structure reduces the number of defective products.

Furthermore, since the resistance FEt of the thermistor chip and the resistance value of the conductive pattern are matched, the characteristics of the product can be made uniform through a very simple process.

(Description of Embodiment) FIGS. 1 and 2 show the structure of a sheet-type temperature-sensitive probe according to an embodiment of the present invention.

In FIGS. 1 and 2, 208.20b indicates two insulating films having the same external shape, and both films 208.20b
0a and 20b are bonded (laminated) with their outer shapes aligned, but conductive patterns 22a and 2 are provided on the bonding surfaces, respectively.
2b is printed and formed in advance. conductive pattern 22a,
22b is formed by silk printing, for example, using a conductive paste in which silver, carbon, or the like is dispersed in a suitable binder.

When the films 20a and 20b are bonded together, the respective conductive patterns 22a and 22b are arranged in parallel at regular intervals.

A thin square thermistor chip 24 is sandwiched and fixed in the center of the circular portions at the tips of both films 20a and 20b. Conductive coatings are formed on both the front and back surfaces of the thermistor chip 24, and the coatings serve as two electrode surfaces. The thermistor chip 24 is a conductive pattern 22a.

It is positioned so that each side forms an angle of 45 degrees with respect to the longitudinal direction of 22b, and the corner portions of both the front and back surfaces are pressed against and electrically connected to the conductive patterns 22a and 22b.

It is preferable to use plastic films for the films 20a and 20b, and to bond both films 20a and 20b by thermocompression bonding. If sufficient bonding strength cannot be obtained by thermocompression bonding, both films 20a and 20b may be bonded together using an adhesive (by applying a heat-sensitive adhesive in advance). Note that the film 20 is not limited to a plastic film, and for example, a paper material coated with plastic can be used as the film 20.
You may use it as a, 20b.

Before pasting the films 20a and 20b together, the thermistor dip 24 is positioned on the inner surface of one of the films. At this time, the thermistor chip 24 may be fixed onto the film using an adhesive.

Note that a square recess corresponding to the thermistor chip 24 may be formed in one or both of the films 20a, 20b, and the chip 24 may be housed in the recess.

The rectangular portions on the base end side of the films 20a, 20b are terminal portions. In this portion, a rectangular terminal window hole 26a is formed in the film 20a, and the conductive pattern 22b of the film 20b to be used is exposed within this window hole. Similarly, the terminal window hole 26 formed in the film 20b
The conductive pattern 22a of the film 20a is exposed in the area b. This exposed conductive pattern is a terminal for external connection, and by sandwiching this portion between the electronic thermometer, the present probe and the electronic thermometer are electrically connected.

The conductive patterns 22a and 22b are formed of a material with relatively high resistivity, and have a resistance value of several ohms to several tens of ohms over the entire length. The resistance value can be changed arbitrarily depending on the blending ratio of the conductive material in the conductive base for printing, the pattern width and length during printing, and the coating thickness, but it can be changed depending on the resistance value of the thermistor chip 24 to be mounted. Selected.

That is, if the thermistor chips 24 are classified into, for example, 10 classes based on variations in their resistance values, then 10 types of films 20a, 20b with conductive patterns 22a, 22b having different resistance values into 10 classes are prepared. and the resistance class of each thermistor chip 24)
By appropriately combining the resistance classes of the Ti patterns 22a and 22b to create a probe, the thermistor chip 24 as seen from the terminals of the Ti patterns 22a and 22b
The overall resistance value, including the resistance value, is kept constant (at a constant temperature).

Note that it is not necessary that the entirety of the conductive patterns 22a, 22b be made of a high-resistance material, but only a portion thereof may be made of a high-resistance material, and the resistance value of that portion may be appropriately set.

Next, an example of the manufacturing process of the above-mentioned sheet-type temperature-sensitive probe will be explained. First, as shown in FIG. 3, a strip-shaped film 50 of a predetermined width is prepared, and terminal window holes 52, 52. ... (holes 5 on both sides)
The second arrangement differs by half a pitch). This film 50
Conductive pattern 54.54 by silk printing on one side of
．． ... to form. In this example, the conductive patterns 54 are formed in parallel with left and right opposite directions, shifted by half a pitch.

Next, as shown in FIG. 4, a thermistor chip 56 is positioned and bonded to the thin end portion of each conductive pattern 54. At this time, each side of the thermistor chip 56 forms an angle of 45 degrees with respect to the longitudinal direction of the conductive pattern 54, and the thermistor chip 56 is arranged so that the back surface of one corner is in contact with the conductive pattern 54.

After bonding the thermistor chip 56, this film 50
(Another film 50 with the same configuration is stacked and positioned with the printed surface of the conductive pattern 54 facing each other. At this time, the conductive pattern 50 stacked on top
As shown by the two-dot chain line a, it is parallel to the lower conductive pattern 50 at a certain interval, and the tip thereof is connected to the thermistor chip 56.
Place it so that it is in contact with the top surface of the other corner. Thereafter, the two stacked films 50.50 are firmly joined by thermocompression bonding. This film bonding force ensures that the thermistor chip 56 and the conductive pattern 54 are electrically connected.

Then, when the laminate film is cut along point 1b in FIG. 4 and perforations 14 are formed, a large number of probes 10° 10, . Two pieces are completed.

The individual probes 10, 10°, . . . can be easily separated from the connecting piece 12 by the perforations 14.

Note that each side of the thermistor chip 56 is connected to the conductive pattern 54.
Since it is tilted at 45 degrees with respect to
Positioning when bonding two films 50.50 together becomes easier.

In the above example, conductive patterns are printed on each of the two films to be laminated, but when placing the terminals of the two conductive patterns on one surface of the completed probe, Two conductive patterns are formed on the bonding surface of one film, and a terminal window hole is formed in the other film to expose a portion of the pattern.

[Brief explanation of drawings]

FIG. 1 is an enlarged perspective view of a probe according to an embodiment of the present invention, FIG. 2 is a perspective view of the probe shown in FIG. 1 with part of the film removed, and FIGS. 5
The figure is a plan view of the product in each manufacturing process of the same bulb. 10...bu, robe, 20a, 20b, 50...
Film, 22a, 22b, 54--conductive pattern,
24.56・=”f−mi′;1.9chi′)bu, 26a,
26b. 52...Terminal window hole. Patent applicant Tateishi Electric Co., Ltd. Agent Patent attorney Tetsuji Iwakura (1 other person) il1 Figure 113 Father Figure 4 et al.

Claims (1)

[Claims] A sheet-type temperature-sensitive probe formed by laminating two insulating films, wherein a thermistor chip is sandwiched and fixed at one end between the films, and the thermistor chip is fixed to the bonding surface of the films. Two conductive patterns are printed and formed, the two electrode surfaces of the thermistor chip are in pressure contact with the conductive patterns, and a terminal window hole is formed on the other end of the film, and the conductive patterns are in contact with each other. The conductive pattern is exposed in the terminal window hole, and part or all of the conductive pattern is formed of a material with relatively high resistivity, and the conductive pattern is formed from a pressure contact point of the thermistor chip to an exposed point in the terminal window hole. A sheet-type temperature-sensitive probe characterized in that a resistance value is selected in accordance with the resistance value of the thermistor chip.