JPH0436071Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a heating element device using a ceramic semiconductor heating element having positive resistance-temperature characteristics, and in particular to a heating element device that can improve thermal efficiency. Regarding.

[Conventional technology]

Conventionally, as shown in Japanese Utility Model Publication No. 44-21744, a heating element device uses a plurality of ceramic semiconductor heating elements having positive resistance-temperature characteristics and tightly fixes them inside a metal case. generally known.

However, in this type of conventional heating element device, the conductor wires are directly adhesively fixed to the ohmic contact electrodes adhered to both sides of the ceramic semiconductor heating element, so it is difficult to arrange each heating element in a predetermined arrangement. It is not easy to do this, and sufficient contact cannot be obtained.Furthermore, when the conductor is fixed to the electrode by brazing, the heating element may be damaged due to thermal stress during brazing. There is a risk.

In addition, in conventional heating element devices, the porcelain semiconductor heating element is simply tightly sealed inside the metal case, so the heat generated by the heating element is not sufficiently transmitted to the metal case, resulting in poor thermal efficiency and heat generation. There is a risk of heat damage to the body.

Therefore, in Japanese Patent Application No. 61-42384, the present applicant previously proposed a heat dissipation case consisting of a first case plate and a second case plate made of metal that face each other at a predetermined interval and whose peripheral edges are connected to each other; A cylindrical center member rising from the center of the case plate and passing through the second case plate and the center, and an ohmic contact electrode arranged around the center member in the heat dissipation case and on a surface facing the inner surface of each case plate. a plurality of plate-shaped ceramic semiconductor heating elements having positive resistance-temperature characteristics, each of which is integrally arranged, an electrode plate that is pressed into contact with the ohmic contact electrode, and an insulation between the electrode plate and the inner surface of the heat dissipation case. an insulating layer that is connected to the electrode plate at one end and is led out through the interior of the central member;
The present invention has proposed a heating element device characterized by comprising a tightening member attached to the central member and tightening both case plates in the approaching direction.

[Problem that the invention attempts to solve]

In the heating element device, since the ceramic semiconductor heating element and the heat dissipation case are pressed together with great force, heat conduction is improved, thermal efficiency can be improved, and thermal damage to the heating element can be prevented. It has many advantages such as

However, since both case plates of the heating element device are made of aluminum alloy, there is a problem in that the case plates are damaged in a relatively short period of time when used in a strong acid solution or alkaline solution.

As a way to prevent this, both case plates are
A possible method is to use a metal material with excellent corrosion resistance and chemical resistance, such as zirconium, titanium, or stainless steel.

However, this type of metal material has very poor thermal conductivity; for example, titanium has a thermal conductivity that is less than 1/10 that of aluminum. Therefore, when this type of metal material is used as a case plate, there is a problem that the thermal efficiency of the heating element device becomes extremely poor.

This idea was created in view of the current situation,
It is an object of the present invention to provide a heating element device that can obtain high thermal efficiency and high insulation even when a metal with excellent corrosion resistance and chemical resistance is used as the material of the outer case.

[Means for solving problems]

The present invention comprises a metal outer case consisting of a first case plate and a second case plate opposed to each other at a predetermined interval and connected at their peripheral edges; a plate-shaped ceramic semiconductor heating element having positive resistance-temperature characteristics, a plurality of which are arranged in an arbitrary arrangement inside the outer case, and an ohmic contact electrode is integrally disposed on the surface facing the inner surface of each of the case plates; an electrode plate pressed against each of the ohmic contact electrodes; and an insulating layer for insulating between each of the electrode plates and the corresponding inner surface of the case plate; and each of the electrode plates and each of the corresponding case plates are pressed against each other via the insulating layer whose at least the surface is heat-melted, pressed against each other via the insulating layer, and integrated together via the insulating layer.

[Effect]

In the heating element device according to the present invention, each electrode plate and each corresponding case plate are pressed together through an insulating layer whose at least the surface is thermally fused, and are integrated through the insulating layer. This electrode plate is then pressed into contact with an ohmic contact electrode of a ceramic semiconductor heating element having a positive resistance-temperature characteristic. Therefore, the contact state between the ohmic contact electrode and the electrode plate can be stabilized, and the heat conduction between the outer case and the electrode plate is improved, and the outer case is made of metal with poor thermal conductivity. Even in the case where the electrode is formed of aluminum, thermal efficiency can be improved and high insulation properties can be maintained. Furthermore, it is also possible to prevent thermal damage to the heating element.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of a heating element device according to the present invention, and this heating element device 1 includes a first case plate 2
The outer case 2 has a disc-shaped outer case 2 consisting of a second case plate 2b and a second case plate 2b. It is drawn out to the outside through the inside of a cylindrical central member 5 arranged in the cylindrical center member 5.

The first case plate 2a has a shallow cylindrical container shape with an outer flange 6 at the periphery as shown in FIGS. A convex recess 7 is provided on the outside for positioning and fixing one end by welding, and between this recess 7 and the outer flange 6 is a ring-shaped convexly bent inward of the first case plate 2a. A pressing section 8 is provided.

Further, the second case plate 2b has a shallow drawn lid shape having an outer flange 9 on the periphery that is butted against the outer flange 6 of the first case plate 2a, as shown in FIGS. 5 and 6, At its center, there is a stepped cylindrical part 1 consisting of a large diameter part 10a and a small diameter part 10b.
0 is integrally provided toward the outer edge. As shown in FIG. 5 and FIG.
is provided. Further, between the outer flange 9 of the second case plate 2b and the stepped tube part 10, there is a ring-shaped press that is bent convexly inward of the second case plate 2b, as shown in FIGS. 5 and 6. A processing section 12 is provided, and this press processing section 12 is used to press both case plates 2.
When the outer case 2 is constructed by connecting the outer case 2a and 2b together, it corresponds to the press-processed portion 8 of the first case plate 2a, and presses and clamps the heat generating mechanism 3 from both sides.

Both case plates 2a and 2b are made of titanium, for example.
The outer flanges 6 and 9 of both case plates 2a and 2b are made of a metal material with excellent corrosion resistance and chemical resistance, such as zirconium or stainless steel. After the members 5 are connected, they are connected together by welding 13 in an inert atmosphere, as shown in FIG.

The heat generating mechanism 3 disposed inside the outer case 2 configured as described above includes six disc-shaped ceramic semiconductor heating elements ( (hereinafter referred to as PTC) 14, and ohmic contact electrodes 14a are integrally arranged on both surfaces of each PTC 14, respectively.

As shown in FIGS. 7 and 8, each of these PTCs 14 is housed in six positioning holes 15a provided at equal intervals in the circumferential direction in a donut disk-shaped positioning plate 15 made of, for example, laminated mica. , electrode plates 16 which also serve as heat dissipation plates are arranged on both sides of aluminum, copper, silver, or alloys thereof, and are formed in the shape of a donut disk with a slightly thick wall.The outer surfaces thereof are made of, for example, polyimide or Insulating sheets 17 in the shape of donut thin disks having heat resistance such as polytetrafluoroethylene are arranged. And with this insulating sheet 17,
Each electrode plate 16 and each corresponding case plate 2a,
2b is electrically insulated from the inner surface thereof, and these are welded together via an insulating sheet 17.

That is, each electrode plate 16 and each corresponding case plate 2a, 2b have an insulating sheet 17 between them.
The insulation sheet 17 is heated under pressure with the insulation sheet 17 interposed therebetween.
After softening and melting the surface, it is cooled. As a result, the surface layer of the melted insulating sheet 17 is transferred to the electrode plate 16 and the case plate 2.
The electrode plates 16 and the case plates 2 a and 2 b are integrated with each other through the insulating sheet 17 by solidifying the electrode plates 16 and the case plates 2 a and 2 b by entering into the irregularities on the surfaces of the electrode plates 16 and 2 b. Each electrode plate 16 and each case plate 2a, 2b
The contact part with the insulating sheet 17 is the insulating sheet 1
In order to improve the adhesion force due to the anchor effect of No. 7, a predetermined roughening process is applied to each of them.

As shown in FIGS. 7 and 8, one ends of conductive wires 4a and 4b are respectively connected to the inner edge portion of each electrode plate 16, and both conductive wires 4a and 4b
is passed through the center of the heat generating mechanism 3, and further passed through the inside of the central member 5 as shown in FIG. 1 and drawn out to the outside.

As shown in FIG. 9, the central member 5 is threadedly connected to a proximal end member 18 that is spot-welded to the recess 7 at the center inside the first case plate 2a, and to the distal end side of the proximal end member 18. a cylindrical male threaded member 19;
The conductors 4a, 4 are inserted into this male threaded member 19.
A protection tube 20 is provided to protect b.

As shown in FIG. 10, the proximal end member 18 is composed of a disk-shaped welded portion 18a that is fitted into the recessed portion 7 and spot-welded, and a cylindrical female threaded portion 18b that rises from this welded portion 18a. has been
Slits 21 are provided in two radially opposed locations on the circumferential surface of the female threaded portion 18b, extending in the axial direction from the tip. The conductive wires 4a, 4b are drawn into the center member 5 through the slit 21.

Further, the male threaded member 19 is shown in FIGS. 9 and 1.
1, the female threaded portion 1 of the proximal end member 18
8b, and a large-diameter male threaded portion 19b continuous to the small-diameter male threaded portion 19a in a stepped manner.
As shown in FIG. 1, a mounting nut 23 for mounting the heating element device 1 to an object 22 to be mounted is screwed into the mounting nut 9b.

In FIG. 1, numerals 24 and 25 are resin or rubber packings, which are attached to the heating element device 1.
The optimal material is selected as appropriate depending on the type of solution to be heated.

Next, the operation of this embodiment will be explained.

When manufacturing the heating element device 1, first, the welding portion 18a of the base end member 18 is spot-welded to the recessed portion 7 in the inner central portion of the first case plate 2a.

Next, an insulating sheet 17 is interposed between the inner surface of each case plate 2a, 2b and each electrode plate 16, and each case plate 2a, 2b and each electrode plate 16 are heated while being pressed. Then, the surface of the insulating sheet 17 softens and melts, and penetrates into the uneven portions of the surfaces of each case plate 2a, 2b and each electrode plate 16. Therefore, each case plate 2a, 2b and each electrode plate 16 are cooled, and the insulating sheet 17 is fixed. Thereby, each case plate 2a, 2b and each electrode plate 16 are integrated with each other via the insulating sheet 17.

Next, the PTC 14 is placed between the two insulated electrode plates 16.
Then, the positioning plate 15 is placed in the assembled state shown in FIG. 7, and the conductive wires 4a, 4b are drawn into the female threaded portion 18b through the slit 21. And furthermore,
With the conductive wires 4a and 4b passed through the protective tube 20 and the male threaded member 19, the male threaded member 19
The small diameter male threaded portion 19a is screwed into the female threaded portion 18b. As a result, as shown in FIG. 9, the tip of the small diameter portion 10b of the stepped tube portion 10 at the center of the second case plate 2b is aligned with the tip of the female threaded portion 18b and the large diameter male threaded portion 19.
It is clamped and fixed between the end face of b, and both case plates 2
The centers of a and 2b are tightened and fixed in a direction in which they approach each other. At this time, the proximal member 1
Since the female threaded portion 18b of No. 8 is provided with the slit 21, normally the female threaded portion 18b would expand outward when the male threaded member 19 is tightened, but as shown in FIG. Since the outer circumferential portion of the tip of the tube is supported by the small diameter portion 10b of the stepped tube portion 10, there is no such fear at all. Therefore, the male threaded member 19 can be strongly tightened.

After connecting the central parts of both case plates 2a and 2b in this way, both case plates 2a and 2b
is pressed from the outside to bring the outer flanges 6 and 9 of the outer periphery into close contact with each other. In this state, both flanges 6 and 9 are integrally connected by welding 13. At this time, in order to prevent oxidation of both case plates 2a and 2b, welding 13 is preferably performed in an inert atmosphere, and in order to prevent damage to the insulation sheet 17 etc. due to the heat of welding 13, both case plates 2a and 2b are welded in an inert atmosphere. 2a,
2b, it is preferable to actively cool parts other than the weld 13 part.

Both case plates 2a and 2b are tightened at the center by the central member 5, and the peripheral edges are connected by welding 13 in a pressed state, so that each electrode plate 16 and the ohmic contact electrode of the PTC 14 14a will come into pressure contact with a strong force. Moreover, since each electrode plate 16 and each case plate 2a, 2b are integrated via an insulating sheet 17,
Even if the case plates 2a and 2b are made of a metal with poor thermal conductivity such as titanium, efficiency can be greatly improved and high insulation properties can be obtained.
Further, since partial heating is eliminated, thermal damage to the PTC 14 can be effectively prevented. Also case plate 2
Even if the thermal expansion coefficients of a, 2b and the electrode plate 16 are different, the insulating sheet 17 functions as a buffer material, and the close contact between the two is not impaired.

In the above embodiment, the insulating layer is an insulating sheet 1 made of polyimide or polytetrafluoroethylene.
7 has been described, but these may be applied to form an insulating layer. Also the 12th
As shown in the figure, the outer surface of the natural mica 26 may be wrapped with two insulating sheets 17 to form an insulating layer.

Further, in the above embodiment, the case where the outer case 2 has a circular shape has been described, but it may have another shape such as a square, and similar effects can be expected.

[Effect of idea]

As explained above, in the present invention, each case plate and each electrode plate constituting the outer case are pressed together through an insulating layer whose surface is at least thermally fused, and are integrated through the insulating layer. Even if the outer case is made of a metal with poor thermal conductivity, high thermal efficiency and insulation can be obtained, and thermal damage to the PTC due to partial heating can be prevented. Further, even if the thermal expansion coefficients of each case plate and each electrode plate are different, the insulating tank functions as a buffer material, and the integrity of the two is not impaired.

[Brief explanation of drawings]

Fig. 1 is a partial sectional view of a heating element device showing an embodiment of the present invention, Fig. 2 is a detailed view of the first case plate seen from the inside, Fig. 3 is a sectional view taken along the - line in Fig. 2; Figure 4 is the right side view of Figure 3, Figure 5 is a detailed view of the second case plate seen from the inside, and Figure 6 is the - of Figure 5.
7 is a sectional view of the heating mechanism, FIG. 8 is a similar exploded perspective view, FIG. 9 is a sectional view showing details of the central member, FIG. 10 is a perspective view of the base end member, and FIG.
The figure is a cross-sectional view of the male threaded member and the protective tube, and FIG. 12 is a cross-sectional view showing another example of the insulating layer. 1... Heating element device, 2... Outer case, 2a...
First case plate, 2b...Second case plate, 3...Heating mechanism, 5...Central member, 6, 9...Outer flange, 13...Welding, 14...PTC, 14a...
Ohmic contact electrode, 16... Electrode plate, 17... Insulating layer, 26... Natural mica.

Claims (1)

[Claims for Utility Model Registration] 1. A metal outer case consisting of a first case plate and a second case plate facing each other at a predetermined interval and connected to each other from the peripheral edge; a plurality of metal outer case plates arranged in an arbitrary manner within this outer case; a plate-shaped ceramic semiconductor heating element having positive resistance-temperature characteristics, in which ohmic contact electrodes are integrally arranged on a surface facing the inner surface of each of the case plates; an insulating layer that insulates between each electrode plate and the corresponding inner surface of each case plate; each electrode plate and each corresponding case plate have at least a surface A heating element device characterized in that the heating element device is pressure-welded through a thermally fused insulating layer and is integrated through the insulating layer. 2. The scope of the utility model registration claim, characterized in that at least the outer surfaces of the first case plate and the second case plate are made of a metal with excellent corrosion resistance and chemical resistance, such as zirconium, titanium, or stainless steel. The heating element device according to item 1. 3. The heating device according to claim 1 or 2 of the utility model registration claim, wherein the peripheral edges of the first case plate and the second case plate are interconnected by welding in an inert atmosphere. body equipment. 4. The heating element device according to claim 1, 2, or 3 of the utility model registration, wherein the insulating layer is formed of a heat-resistant resin sheet such as polyimide or polytetrafluoroethylene. 5. Utility model registration claims 1, 2, 3, or 4, characterized in that the electrode plate is made of aluminum, copper, silver, or an alloy thereof.
The heating element device described in Section 1. 6 Utility model registration claims 1, 2, and 3, characterized in that the electrode plate and the case plate are roughened on the surface facing the insulating layer.
5. The heating element device according to item 4, item 5, or item 5.