JPH03152901A - Positive coefficient thermistor device - Google Patents

Abstract

PURPOSE:To completely fix the two main surfaces of a thermistor by a method wherein one main surface positioned opposing to the other main plane, the heat heat generating surface, of the thermistor is arranged facing the supporting surface of a supporting member through the intermediary of a spacer, and at the same time, the other main surface and the supporting surface of the supporting member are adhered using the bonding agent in the aperture part of the spacer. CONSTITUTION:A thermistor 4 is arranged in such a manner that its main surface B, which is facing a main surface A becoming a heating surface, will be opposing to the supporting surface 111 of a supporting member 11 through the intermediary of a spacer 9. Said main surface A, to be used as a heating surface, is set at a fixed position to be determined by the thickness T1 of the spacer 9 based on the supporting surface 111, and as a result, the variation in height, inclination and the like of the main surface A is eliminated. Also, the main surface B of a positive coefficient thermistor and the supporting surface 111 of the supporting member 11 are bonded using a bonding agent 15. The positional deviation of the thermistor 4 on the supporting surface 111 of the supporting member 11 is prevented by the above-mentioned bonding, and the thermistor can be supported at the prescribed position of the supporting member.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a surface heating type positive temperature coefficient thermistor packaged in which one principal surface serving as a heat generating surface of the positive temperature coefficient thermistor and the other principal surface facing the Arranging the PTC thermistor to face the receiving surface of the support through a spacer, and bonding the other main surface of the PTC thermistor and the receiving surface of the support to each other with an adhesive placed in the opening of the spacer. This eliminates problems such as inclination of the heat generating surface of the PTC thermistor, fluctuation in height, and extrusion of adhesive, and makes it possible to securely fix the PTC thermistor to the support.

<Prior Art> As a positive temperature coefficient thermistor device of this type, one described, for example, in Japanese Patent Publication No. 5B-14221 is known. FIG. 9 is a plan view of a conventional positive temperature coefficient thermistor device, and FIG. 10 is a plan view of a conventional positive temperature coefficient thermistor device.

This is a cross-sectional view along a line, where 1 is a positive temperature coefficient thermistor body, and 2.3 is a pair of electrodes.

The positive temperature coefficient thermistor body 1 has a flat plate shape, and has a pair of electrodes 2.3 formed on one surface A of opposing principal surfaces A and B.

The electrode 2.3 has lead electrodes 201, 301 and branch electrodes 211-214, 311-314 provided along opposite sides of the PTC thermistor body 1. The branch electrodes 211 to 214 belonging to the electrode 2 and the branch electrodes 311 to 314 belonging to the electric fi3 are arranged in an alternating arrangement with an interval d1 between them. Therefore, branch electrodes 211-2
14 and the branch electrodes 311 to 314, a surface heating type positive temperature coefficient thermistor device is obtained in which each interval d1 formed between the branch electrodes 311 to 314 serves as a heating surface.

The above-mentioned positive temperature coefficient thermistor device is used by being attached to a support such as a case, with the main surface A, which is the heat generating surface, exposed, and the main surface B, which is the supporting surface.

<Problems to be Solved by the Invention> However, the conventional positive temperature coefficient thermistor device described above has the following problems.

(b) This type of surface heating type positive temperature coefficient thermistor device is used by being attached to a support such as a case, with the main surface A side, which is the heat generating surface, exposed, and the main surface B side serving as the supporting surface. . At this time, if the support body and the PTC thermistor device are not fixed, the position of the PTC thermistor device will shift on the support body, and the heating point with respect to the heated object will change. This causes the problem of

Furthermore, if the support and the PTC thermistor device are not combined, they must be handled separately when attaching them to a heated object, making assembly difficult.

(b) As a means to solve the above problems, generally,
As shown in FIG. 11, an adhesive is applied onto the support C, and the PTC thermistor 1 is fixed onto the support C using the adhesive. However, depending on the bonding process, the position of the heat generating surface of the PTC thermistor 1 tends to change, or the PTC thermistor 1 is easily installed at an angle, so that the heat generating surface A of the PTC thermistor 1 is at a predetermined height. It is difficult to set it so that

For example, as shown in FIG. 12, the positive temperature coefficient thermistor 1 may be installed at an angle θ, or as shown in FIG. Problems may occur, such as the height Hl changing or the adhesive spilling out to the surrounding area.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems and to maintain the position of the heat generating surface of a positive temperature coefficient thermistor at a predetermined height position so that the positive temperature coefficient thermistor can be reliably adhesively fixed on a support. An object of the present invention is to provide a thermistor device.

<Means for Solving the Problems> In order to solve the above-mentioned problems, the present invention provides a positive temperature coefficient thermistor device including a positive coefficient thermistor, a support, and a spacer, wherein the positive coefficient thermistor has a has a pair of electrodes on both main surfaces thereof, the spacer is plate-shaped and has an opening in its plane, and the positive temperature coefficient thermistor, the support body, and the spacer The other main surface of the positive temperature coefficient thermistor, which is opposite to the main surface having the pair of electrodes, is arranged to face the receiving surface of the support with the spacer interposed therebetween. The main surface of the spacer and the receiving surface of the support are bonded to each other with an adhesive placed in the opening of the spacer.

<Function> Since a positive temperature coefficient thermistor has a pair of electrodes on one of the opposing main surfaces of the positive temperature coefficient thermistor body, it is a surface heating type positive temperature coefficient thermistor device in which the main surface provided with the pair of electrodes serves as the heating surface. is obtained.

A positive temperature coefficient thermistor is arranged so that the other main surface, which is opposite to the main surface that is the heat generating surface, faces the receiving surface of the support with a plate-shaped spacer interposed therebetween. The position of the main surface is set at a constant position determined by the thickness of the spacer, using the receiving surface of the support as a reference, and the height fluctuation and inclination of the heat generating surface do not occur.

The other main surface of the positive temperature coefficient thermistor and the receiving surface of the support are:
Since they are bonded to each other with an adhesive, displacement of the positive temperature coefficient thermistor on the receiving surface of the support is prevented.

Moreover, the spacer has an opening in its plane, and the other main surface of the PTC thermistor and the receiving surface of the support are bonded to each other by an adhesive placed in the opening of the spacer. The adhesive application area is limited within the opening, and problems such as variations in the height of the heating surface, inclination, and extrusion of the adhesive due to variations in the thickness of the adhesive are prevented.

<Example> Fig. 1 is an exploded perspective view of a positive temperature coefficient thermistor device according to the present invention, Fig. 2 is a partially assembled sectional view of the main parts, and Fig. 3 is a partially sectional view of the PTC thermistor device attached to a heated object. It shows. In the figure, 4 is a positive temperature coefficient thermistor, 5 to 8 are terminal fittings,
9 is a spacer, 10 is a heat sink, 11 is a support, 12 is a presser piece, 13 is a connector, and 14 is a heated body.

The PTC thermistor 4 has a pair of electrodes 42.4 on one main surface A of both opposing main surfaces A and B of the PTC thermistor body 41.
3, and the main surface A provided with this pair of electrodes 42 and 43 becomes a heat generating surface. The terminal fittings 5 to 8 are attached to the sides of the PTC thermistor 4 and serve as power supply terminals for the electrodes 42 and 43. When attaching the terminal fittings 5 to 8 to the positive temperature coefficient thermistor 4, use the clamping openings 51 of the clip parts 52 to 82.
The sides on which the lead electrodes of the positive temperature coefficient thermistor body 41 are formed are sandwiched between the two main surfaces A and B by steps 81 to 81.

The spacer 9 is made of a mica laminate or the like, and has an opening 91 in its surface.

The heat sink 10 is formed into a flat plate using alumina porcelain or the like.

The support body 11 is formed into a case shape using alumina porcelain or the like, and has a substantially flat receiving surface 111 on its negative side. The holding piece 12 is made of a springy material such as a thin stainless steel plate, and has a curved central portion 121 to provide a predetermined springiness.
22.123 is provided.

In the assembled state, the PTC thermistor 4 has a main surface B, which is opposed to the main surface A, which is a heat generating surface, with a spacer 9 interposed therebetween.
It is arranged so as to face the receiving surface 111 of the support body 11. The position of the main surface A, which is the heat generating surface, is set at a constant position determined by the thickness T1 of the spacer 9 with respect to the receiving surface 111 of the support 11, so that fluctuations in height, inclination, etc. of the main surface A may occur. It disappears.

Further, the main surface B of the positive temperature coefficient thermistor 4 and the receiving surface 111 of the support body 11 are bonded to each other by an adhesive 15. This adhesion prevents the PTC thermistor 4 from shifting on the receiving surface 111 of the support 11, securely holds the PTC thermistor 4 at a predetermined position on the support 11, and prevents the PTC thermistor 4 from shifting due to movement of the PTC thermistor 4. 5 to 80 metal fittings can be reliably prevented from being bent or damaged.

The main surface B of the positive temperature coefficient thermistor 4 and the receiving surface 11 of the support 11
1 and 1 are adhered to each other by adhesive 15 placed in opening 91 of spacer 9.

Therefore, the area to which the adhesive 15 is applied is limited to the inside of the opening 91, and problems such as variations in the height of the main surface A, tilting, and protrusion of the adhesive 15 due to variations in the thickness of the adhesive 15 do not occur. Although not shown, the receiving surface 111 of the support body 11
A recess may be provided to correspond to the opening 91, and the adhesive 15 may be placed in the recess.

The heat radiator 10 and the main surface A of the PTC thermistor 4 are bonded together with a heat conductive resin layer 16 such as a heat conductive silicone resin interposed therebetween in order to improve heat conduction between the two.

To attach this assembly to the object to be heated 14, as shown in FIG. Fixed at 14.

A plurality of openings 91 of the spacer 9 may be provided as shown in FIG. 4, or may be provided at the edge as shown in FIG.

Next, details of the positive temperature coefficient thermistor 4 and the terminal fittings 5 to 8 will be explained. First, as shown enlarged in FIG. 6, the positive temperature coefficient thermistor 4 has a plurality of branch electrodes 421 to 425, 431 to 436 constituting electrodes 42 and 43, and lead electrodes 44 to 47. . The lead electrodes 44 to 47 are provided along two opposing sides of the PTC thermistor body 4. Each of these electrodes is formed as a conductive film.

The branch electrodes 421 to 425 of the electric box 42 and the branch electrodes 431 to 436 of the electrode 43 are arranged to face each other at a distance d on the main surface A of the PTC thermistor element body 41. These branch electrodes 421-425.431
436 is deposited on the inner wall surface of the groove provided in the positive temperature coefficient thermistor body 41, or is deposited so as to fill the inside.

The sides of the PTC thermistor body 41 on which the lead electrodes 44 to 47 are provided are deep from the main surface A.

The stepped surfaces 401 to 404 are depressed at a lower angle. Step surface 40
The depth of 1 to 404 is larger than the thickness t of the lead electrodes 44 to 47 formed as conductive films, and the surface of the lead electrodes 44 to 47 and the positive characteristic damister element body 41
A gap given by the difference (h+t+) between the two surfaces is generated between the main surface and the surface 12. This gap allows the terminal fittings 5 to 8 to be positioned within the stepped surface, and the positive temperature coefficient thermistor element body 4 which becomes the heat generating surface.
It is used to thermally bond the main surface A of 1 to the object to be heated.

The lead electrode of the electrode 43 is divided into a plurality of parts 45 to 47. Although not shown, the lead electrode 44 of the electrode 42
can also be divided into multiple parts. When the lead electrodes 44 to 47 are divided into a plurality of parts, heat generation can be controlled. Although not shown in the drawings, the PTC thermistor body 41 is not limited to a rectangular shape, but may be formed in other angular shapes or circular arc shapes.

Terminal fittings 5-8 are prepared corresponding to the number and shape of lead electrodes 45-47. Among the terminal fittings 5 to 8, the terminal fitting 5 includes a clip portion 52 having a clamping opening 51 opened in one direction, and a terminal portion 5 connected to the clip portion 52.
3, and an overcurrent fusing portion 54 disposed at a connecting portion between the clip portion 52 and the terminal portion 53. FIG. 7 is a perspective view of the terminal fitting 5. The clip portion 52 is U-shaped, and cutouts 56 are provided at appropriate intervals.

This is to ensure electrical contact with the beam electrode 44. The clip portion 52 also has a central notch 57.
It is divided into two parts, each of which is separately connected to a terminal part 53 via an iM current cutoff part 54.

The terminal portion 53 has one end connected to the other end of the overcurrent fusing portion 54 and extends in a direction perpendicular to the direction in which the overcurrent fusing portion 54 is arranged. Overcurrent fusing part 54 of terminal part 53
A tongue piece 55 that is bent in the opposite direction to the overcurrent fusing part 53 is provided on one end side where the overcurrent fusing part 53 is connected. Tongue piece 55
is provided at a slightly higher position than the overcurrent fusing portion 54.

The overcurrent fusing portion 54 is formed as a narrow portion, one end of which is connected to the clip portion 52, and the other end extending toward the clip opening 51. Overcurrent fusing part 5
The cross-sectional area, length, etc. of 4 are determined in consideration of the allowable current value. The overcurrent fusing section 54 shown in the embodiment has two
This is provided, and each overcurrent fusing part 54 is arranged so as to connect the clip part 52 and the terminal part 53.

The other terminal fittings 6 to 8 are similar to the terminal fitting 5 except that they do not have overcurrent fusing parts, and have clip parts 62 to 82 with openings 61 to 81 opened, and clip parts 62 to 82 with openings 61 to 81. ~
It has terminal parts 63 to 83 connected to 82, respectively.

As described above, among the terminal fittings 5 to 8, the terminal fitting 5 has the A current fusing part 54 disposed at the connection part of the clip part 52 and the terminal part 53, so that the PTC thermistor body 5 If overcurrent flows due to deterioration etc., the overcurrent fusing section 5
When the current density of 4 exceeds the allowable value, the current density exceeds the allowable value and the terminal portion 53 and the clip portion 52 contacting the lead electrode 44 of the positive temperature coefficient thermistor 4 are electrically cut off. Therefore, a surface heating type positive temperature coefficient thermistor device having a self-overcurrent protection function can be realized without adding an external overcurrent protection element such as a fuse. Although not shown, terminal fittings 6 to 8
It is also possible to provide an overcurrent fusing section.

In the embodiment, on the end side of the terminal part 53 of the terminal fitting 5,
Since a tongue piece 55 is provided which bends in the opposite direction to the overcurrent fusing part 54, the sides of the positive temperature coefficient thermistor 4 are sandwiched from both main surfaces A and B sides by the clamping opening 51, and the terminal fitting is inserted. 5
When attached to the positive temperature coefficient thermistor 4, the tongue piece 55 comes into contact with the main surface B of the positive temperature coefficient thermistor 4, and supports the force in the direction of arrow C0 against the terminal fitting 5. Therefore, the overcurrent fusing portion 54 is formed as a narrow portion and has low mechanical strength.
is reinforced by the action of the tongue piece 55, and damage to the overcurrent fusing portion 54 due to external force is prevented.

The tongue piece 55 is set at a higher position than the overcurrent fusing part 54, and in the assembled state where the tongue piece 55 is in contact with the main surface B,
A gap G2 is created between the overcurrent fusing portion 54 and the main surface B. Therefore, when an overcurrent flows through the overcurrent fusing part 54, the heat conduction from the At clear current fusing part 54 to the positive temperature coefficient thermistor 4 becomes extremely low, and the temperature of the overcurrent fusing part 54 rises rapidly. and is quickly fused.

FIG. 8 is a diagram showing the mounting structure between the PTC thermistor 4 and the terminal fittings 5 to 8, in which the terminal fittings 5 to 8 have an end height h
2, the two opposing main surfaces of the positive temperature coefficient thermistor element 41 are arranged within the stepped surfaces 401 to 404 so as to be lower by Δh than the main surface A of the positive temperature coefficient thermistor element 41, which becomes the heat generating surface. It is attached so as to be elastically clamped from sides A and B. This makes it possible to thermally bond the main surface A of the PTC thermistor body 41, which is a heat generating surface, to the heat sink 10.

<Effects of the Invention> As described above, the positive temperature coefficient thermistor device according to the present invention provides the following effects.

(a) A positive temperature coefficient thermistor has a pair of electrodes on one of the two opposing main surfaces of the positive temperature coefficient thermistor body, so a surface heating type positive temperature coefficient thermistor device in which the main surface provided with the pair of electrodes serves as a heat generating surface. can be provided.

(b) In a positive temperature coefficient thermistor, the main surface serving as the heat generating surface and the other main surface in an opposing relationship are arranged through a spacer in which the other main surface is plate-shaped.
Since it is arranged so as to face the receiving surface of the support, it is possible to provide a positive temperature coefficient thermistor device that does not cause height fluctuations or inclinations of the heat generating surface.

(c) Since the other main surface of the hourly thermistor and the receiving surface of the support are bonded to each other with an adhesive,
It is possible to provide a positive temperature coefficient thermistor device that can prevent the positional shift of the positive temperature coefficient thermistor and can reliably prevent bending, damage, etc. of components such as terminal fittings combined with the positive temperature coefficient thermistor.

(d) The spacer has an opening in the plane, and the other main surface of the PTC thermistor and the receiving surface of the support are bonded to each other with an adhesive placed in the opening of the spacer. Therefore, it is possible to provide a positive temperature coefficient thermistor device that does not cause problems such as height position fluctuations, inclinations, and adhesive extrusion of the heat generating surface due to changes in the thickness of the adhesive.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of a positive temperature coefficient thermistor device according to the present invention, FIG. 2 is a partially assembled cross-sectional view of the main parts, FIG. Figure and 5th
The figures are perspective views of different embodiments of the spacer, Figure 6 is a perspective view of a positive temperature coefficient thermistor, Figure 7 is a perspective view of a terminal fitting,
FIG. 8 is a diagram showing the state of connection between a PTC thermistor and a terminal fitting, and FIG. 9 is a plan view of a conventional PTC thermistor device.
FIG. 10 is a sectional view taken along line B+B+ in FIG. 9, FIG. 11 is a diagram showing the assembly process of a conventional positive temperature coefficient thermistor device, and FIGS. 12 and 13 are diagrams showing the problems. 4... Positive temperature coefficient thermistor 41... Positive temperature coefficient thermistor body 42, 43... Pair electrodes 44-47... Lead electrodes 5-8... Terminal fitting 9... Spacer 91... Opening 10... Heat sink 11... Support 15... Adhesive 9 JP-A-3 152901 (7)

Claims (2)

[Claims] (1) A PTC thermistor device including a PTC thermistor, a support, and a spacer, wherein the PTC thermistor has a pair of electrodes on one of the opposing main surfaces of a PTC thermistor body. the support has a receiving surface, the spacer is plate-shaped and has an opening in the plane, and the other main surface of the PTC thermistor is connected to the spacer. The other main surface of the PTC thermistor and the receiving surface of the support are placed in the opening of the spacer, and A positive temperature coefficient thermistor device characterized in that the positive temperature coefficient thermistor device is bonded to each other by a bonded adhesive. (2) Each of the pair of electrodes of the PTC thermistor has a lead electrode, the lead electrode is provided along a side of the PTC thermistor body, and the lead electrode includes: Terminal fittings are attached, and at least one of the terminal fittings includes a clip portion with an opening, a terminal portion connected to the clip portion,
and an overcurrent fusing part disposed at a connecting part of the clip part and the terminal part, and the side of the positive temperature coefficient thermistor body is sandwiched from both main surfaces by the clipping opening of the clip part. 2. The positive temperature coefficient thermistor device according to claim 1, wherein the terminal fitting is attached to the positive temperature coefficient thermistor.