JPH01213978A - Surface-shaped heat emitting body - Google Patents

Abstract

PURPOSE:To provide a surface-shaped heat emitting body with self temp. adjusting function and overheat preventive function and enable suppression of unevenness in the temp. distribution by furnishing a PTC heat emitting region formed on a cloth base, a No.1 electrode consisting of a plurality of electrode divisions, and a No.2 electrode consisting of a plurality of electrode divisions arranged apart from the No.1 electrode. CONSTITUTION:In a No.1 surface-shaped heat emitting body 10, a No.1 and a No.2 electrode 14, 15 consisting each of a plurality of electrode divisions are arranged to PTC heat emitting regions 12A, 12B formed to at least one surface of a cloth base 11. This suppresses the PTC heat emitting regions 12A, 12B being turned into overheated condition to enlarge along electrode, which in turn binders enlargement of the overheated zone to suppress unevenness in the temp. distribution. This provides effectively the self temp. adjusting function and the overheat preventive function.

Description

Detailed Description of the Invention (1) Purpose of the Invention [Field of Industrial Application] The present invention relates to a planar heating element, which has a self-temperature function and an overheating prevention function, and has an uneven temperature distribution. This invention relates to a planar heating element in which oxidation is suppressed.

[Prior Art] Conventionally, as shown in FIG. 14, this type of planar heating element is made by using conductive particles (for example, carbon black or metal) for a crystalline polymer compound with a positive temperature coefficient of electrical resistance. P
It has been proposed to form a 12° TC heat generating layer by disposing it on a cloth base material (not shown) by coating or the like.

[Problems to be solved] However, in the conventional planar heating element, (i) when the heating layer, that is, the PTC heating layer 12° is overheated due to poor contact with the electrodes, the heat conduction between the electrodes 14' and 15° is Since the coefficient is extremely larger than the thermal conductivity coefficient of the heat generating layer, that is, the PTC heat generating layer 12°, the passage of the ship through the electrodes 14' and 15'
Heat is diffused from the electrode 14°.

There is a drawback that an overheated region is formed along the 15° angle, and (ii) when overheated, the electrical resistance of the heat generating layer, that is, the PTC heat generating layer 12° increases only in that area.
Considering that the value of the current flowing between 4° and 15° is constant across the cross section, the amount of heat generated is proportional to the resistance value, and the overheated part will be heated even more.

The disadvantage is that the temperature distribution becomes uneven, resulting in (
iii) There is a drawback that the PTC characteristics cannot be exhibited, and furthermore, (iv) if the PTC characteristics are to be maintained, the electrode 1
The distance between 4" and 15 degrees had to be reduced, and there was a disadvantage that an increase in weight and wall thickness and loss of flexibility could not be avoided.

Therefore, in order to eliminate these drawbacks, the present invention aims to provide a planar heating element that has a self-temperature control function and an overheating prevention function, and is capable of sufficiently suppressing non-uniformity of temperature distribution. It is something.

(2) Structure of the invention [IF, 1m point solution] The first solution to the problem provided by the present invention is as follows: (a) a cloth base material; (b) a +iO cloth base material; a PTC heat generating region formed over at least one surface; (C) a first electrode consisting of a plurality of divided electrodes arranged for the PTC heat generating region; and (d) a first electrode for the PTC heat generating region. and a second electrode consisting of a plurality of divided electrodes arranged apart from one electrode.

The second solution to the problem provided by the present invention is as follows.

“(a) With a cloth base material.

(b) a PTCQ heat region formed on at least one side of the cloth base material; and (c) a first heat region disposed adjacent to both sides of the PTC heat region. and a second normal heat generation area.

(d) Jingji 1. The first. and a second electrode.''

[Function] The first planar heating element according to the present invention has first and second electrodes each comprising a plurality of divided electrodes arranged in a PTC heating region formed on at least one surface of a cloth base material. Therefore, (i) it acts to suppress the PTC heat generation region from becoming overheated and expanding along the electrode, and (ii) it prevents the expansion of the overheating region and suppresses uneven temperature distribution. As a result, (iii) the self-temperature regulation function S and the overheating prevention function are effectively achieved.

Further, in the second planar heating element according to the present invention, a normal heating area is provided on both sides of the PTC heating area formed on at least one surface of the cloth base material, and a second heating area is provided on each side of the PTC heating area formed on at least one side of the cloth base material. 1. Since the second electrode is provided,
(iv) Even if the normal heating area becomes overheated and the overheating area expands along the electrode, it acts to prevent the PTC heating area from becoming overheated, and as a result, the above (ii)
It acts as Σ and (iii).

[Example] Next, the present invention will be specifically described with reference to the accompanying drawings.

FIG. 1 is a plan view showing a first embodiment of a planar heating element according to the present invention.

FIG. 2 is a cross-sectional view of the embodiment shown in FIG. 1 taken along the line ■-■.

FIG. 3 is a partially cutaway plan view showing a second embodiment of the sheet heating element according to the present invention.

FIG. 4 is a determination along the rV-17 line of the FIG. 3 embodiment.

FIG. 5 is a plan view showing a third embodiment of the sheet heating element according to the present invention.

FIG. 6 is a sectional view taken along the line VI-VI of the embodiment shown in FIG.

FIG. 7 is a partially cutaway plan view showing a fourth embodiment of the sheet heating element according to the present invention.

FIG. 8 is a sectional view taken along the line Vllll--Vllll of the embodiment of FIG. 7. FIG.

9 to 13 are explanatory views of the operation of the planar heating element according to the present invention.

First, the structure and operation of a first embodiment of the planar heating element according to the present invention will be described in detail with reference to FIGS. 1 and 2.

The bar is a planar heating element according to the present invention, and PTC heating regions (that is, heating regions having a positive temperature coefficient of electrical resistance) 12^ and 12B are arranged on at least one surface of the cloth base material 11. , and the electrodes 14. are spaced apart from each other with respect to the surface of the PTC heating region 12^. Is are arranged respectively. The electrode 14 includes a plurality of divided electrodes 14a =
14j, and the electrode 15 is formed by a plurality of divided electrodes ISa to 15j.

Electrode 14. Is can be connected to a DC or AC power source (not shown) via connection lines 11i and 17.

The cloth base material 11 is formed of a woven fabric (plain woven fabric or knitted woven fabric) or a nonwoven fabric of synthetic fibers (for example, nylon or Tetron). cloth base material it
The thickness of SO#Lm is normally desirably 1 mm, but is not limited to this.

The planar heating element according to the present invention generates heat as follows.

Thank you! Furthermore, when an appropriate voltage is applied between the electrodes 14 and 15, the electric current between the electrodes 14 and 15 is large because the electrical resistance of the PTC heating regions 12A and 12B is small in the initial low temperature state.
As a result, the amount of heat generated by the PTC heat generating regions 12A and 12B increases. Therefore, the temperature of the planar heating element rises rapidly.

When the sheet heat generation suspension reaches a high temperature, the PTC heat generation area 12A,
Since the electrical resistance of 12B increases and becomes larger, the electrode 14
, 15 becomes small. This reduces the amount of heat generated in the PTC heat generating regions 12A, 12B.

Therefore, the temperature of the planar heating element decreases.

When the temperature of the planar heating element becomes low, the PTC heating area 12A,
Since the electrical resistance of 12B becomes smaller, the current between electrodes 14 and 15 becomes larger again. This increases the amount of heat generated by the PTC heat generating regions 12A and 12B. Therefore, the temperature of the sheet heating element rises again.

By repeating the above operations, the planar heating element according to the present invention exhibits self-temperature function and overheat prevention function.

(Abnormal heating operation) For example, the divided electrode 14d of the electrode 14 and the PTC heating area 1
When a contact failure or the like occurs with 2A, the temperature of the area where the contact failure or the like occurs (referred to as the "overheated region") increases compared to the surrounding area.

1m5wm is 14 itm W"er 1 pole 14a"
14j, it does not expand along the electrode 14 and is limited to a local portion of the PTC heat generating regions 12A, 12B.

In the portions of the PTC heating regions 12A and 12B that have become overheated regions, the electrical resistance increases, so the current decreases.

Therefore, the current from the electrode 14 is transferred to the PTC heating region 12.
It flows to the electrode 15 through the PTC heating area IZA 12B while avoiding the overheated areas of A and 12B. As a result, the PTC heat generating regions 12^, 12B generate heat in the same manner as in the normal heat generating operation described above, except for the overheated region.

As described above, the planar heating element according to the present invention exhibits self-efficiency and overheat protection while suppressing non-uniformity of temperature distribution even in abnormal situations, that is, in the event of overheating.

Next, with reference to FIGS. 1 and 2, a manufacturing method of a first embodiment of the sheet heating element according to the present invention will be described in detail.

(The electrically conductive elastomer composition of the electrically conductive elastomer composite has (i)
A conductive material for adjusting the electric resistance and appropriately setting the amount of heat generated and thus the temperature of the heat generated; (ii) a rubber compounding agent (i.e., a vulcanizing agent as an essential component and a reinforcing filler and a plasticizer as optional components); , a vulcanization accelerator, a vulcanization regulator, a processing aid, an anti-aging agent, and a flame retardant, etc.) are kneaded together. (
For example, it is prepared by kneading and dispersing the mixture using a roll.

As the sheet heating element of the present invention is often used in the air, the elastomer is preferably one that does not deteriorate due to air oxidation, that is, one that does not contain too many unsaturated groups, such as (i) ethylene propylene rubber. , acrylic rubber, silicone rubber, fluororubber, butyl rubber, chlorinated polyethylene, or (ii) polyvinyl chloride containing a plasticizer such as DOP, ie, dioctyl phthalate.

At least one of resins such as resin family polyamide!
It is preferable to use I.

A particulate material or a fibrous material may be used as the conductive material.

As the particulate material, (i) at least L types of materials selected from carbon black materials such as Ketschen black, acetylene black, ECF carbon black, graphite or carbon fiber, or (
ii) At least one metal material selected from nickel powder, copper powder, silver powder, gold powder, aluminum powder, brass powder, metal-coated mica powder, metal-coated glass powder, etc.
It is preferable to use seed material. The amount of the carbon black material added is preferably 5 to 50 parts by weight per 100 parts by weight of the elastomer, and the amount of the metal material added is 10 to 9 parts by weight per 188 parts by weight of the elastomer.
0 part by weight is preferable, and if desired, the carbon black material and the metal material may be used in combination with each other. It is appropriately selected depending on the requirements for conductivity.

Examples of fibrous materials include carbon fiber, metal-coated polymer fiber, metal-coated glass fiber, or metal fiber (for example, aluminum fiber, brass mm, nickel am
> etc. are suitable. The amount of the fibrous material added is preferably 10 to 90 parts by weight per 100 parts by weight of the elastomer.

Examples of reinforcing fillers include white carbon, precipitated calcium carbonate, and fine powdered mica 9 synthetic fibers! l(
It is preferable to use at least one of short fibers such as nylon or tetron, whiskers, and hard clay.

Suitable vulcanizing agents include, for example, sulfur or peroxides. Here, as the peroxide, at least one of dicumyl peroxide, tert-butyl cumyl peroxide, 2,5-dimethyl-2゜5-di(tert-butylperoxy)hexane, etc. is used. If desired, at least IN of ethylene dimethacrylate, trimethylolpropane trimethacrylate, or a polyaryl compound (eg, triarylisocyanurate) may be used in combination.

When sulfur is used as a vulcanizing agent, at least one of benzothiazoles (for example, 2-mercaptobenzothiazole), dithiocarbamates, and thiurams (for example, tetramethylthiuram monosulfide) is used as the vulcanization accelerator. If used, it is suitable.

It is preferable to add a vulcanization accelerator (for example, zinc white, etc.) together with the vulcanization accelerator, since the vulcanization accelerator will function satisfactorily.

As the anti-aging agent, it is preferable to use, for example, at least one of N,N'-diphenyl-P-phenylenediamine P-isopropoxydiphenylamine and N,N'-di-0-tolylethylenediamine.

Flame retardants, together with anti-aging agents, function to ensure product lifespan and safety. ! ! 1 As a fuel, organic phosphorus compounds (for example, tricresyl phosphate,
at least one of the following: cyphenylsulfate, trioctylphosphate, triphenylphosphate, tris(chloroethyl)phosphate, etc.) and an organic halogen compound (e.g. hexabromobiphenyl, pentabromochlorocyclohexane or tris-( 2,3-dibromopropyl-1)
- at least one of the following: - isocyanurate, etc.);
It is preferable to use at least L selected from the group consisting of metal oxides (for example, antimony oxide) and metal hydroxides (for example, aluminum hydroxide or zinc borate). .

As a processing aid, it is preferable to use stearic acid or the like.

(mW of PTC combination) PTC! The u composition (polymer conductive material composition having a positive temperature coefficient of electrical resistance) is, for example, l rho 2 compared to the crystalline polymer compound that functions as a matrix resin.
It is prepared by dispersing conductive particles so as to exhibit conductivity of about 103 Ωcm. That is, PTC
The composition is prepared by putting the crystalline polymer compound and the conductive particles into a mixer (for example, an open roll or kneader) and kneading the compound while heating it to the softening point of the crystalline polymer compound.

As the crystalline polymer compound, it is preferable to use an ethylene acrylic acid copolymer which has a low melting point of 103''C, has carboxyl groups in its side chains, and whose carboxyl groups can be bonded to each other via a polyvalent metal.

Conductive particles include carbon black (furnace carbon black, channel carbon black, thermal carbon black).

If at least one of the following is used: acetylene carbon black, Ketschen black, etc.), graphite powder, carbon fiber, gold aims, metal powder, etc.
The preferred amount of the conductive particles to be added may be appropriately selected as desired, but is particularly preferably from 10 to 70 parts by weight per 100 parts by weight of the crystalline polymer compound.

(Creation of PTC elastomer solution) PTC! The 11 substances are stirred and dissolved together with the conductive elastomer composition in an appropriate solvent (for example, methyl ethyl ketone) to form a PTC elastomer solution.

(Preparation of PTC Composition Sheet) The PTC elastomer solution is coated on the cloth base material 11 to an appropriate thickness and then dried to form a PTC composition sheet.

(Preparation of PTC heating element) [1 The product sheet is cut into an appropriate size as desired to form a PTC heating area element.

The PTC heating region element is directly used as a planar heating element (see FIGS. 1 and 2).

The electrode 14 consisting of divided electrodes 14a = 14j and the divided electrodes 15a to 15a are attached to the surface of the planar heating element element with A1 Kaji Q arrangement using an appropriate conductive adhesive or by vulcanization adhesion or pressing.
15j and the electrodes 15j are arranged spaced apart from each other (
(See Figures 1 and 2).

As a result, a planar heating element according to the present invention is formed.

Here, the electrodes 14 and 15 are made of copper, brass, or stainless steel.

Metal plates such as aluminum, metal foil, metal rods, metal-based,
It is preferably formed of metal twisted yarn or metal net, and in particular, when it is necessary to ensure flexibility for the planar heating element according to the present invention, it is preferably formed of metal wire or metal foil. is preferred.

Next, with reference to FIGS. 3 and 4, the structure of the second embodiment of the sheet heating element according to the present invention will be explained. & and details the action.

The average is a planar heating element according to the present invention, which has a PTC heating area (that is, a heating area where the temperature coefficient of electric resistance is positive) on at least one surface of the cloth base material 21 22A, 22B.
are disposed, and electrodes 24 and 25 are disposed on the surface of the PTC heat generating region 22^ so as to be spaced apart from each other.

The electrode 24 is formed by a plurality of divided electrodes 24a to 24j, and the electrode 25 is formed by a plurality of divided electrodes 25a to 24j.
~25j.

The electrodes 24.25 can be connected to a DC or AC power source (not shown) via connecting lines 26.27.

An insulating polymer film layer, that is, an insulating layer 26 is disposed as a surface layer on the planar heating layer. That is, the cloth base material 21. PTC heating areas 22A, 22B and electrode 2
4. The portion of 25 that forms the outer surface is provided with peripheral members (
An insulating polymeric film layer or insulating layer 26 is provided to avoid direct contact with (not shown).

The cloth base material 21 is formed of a woven fabric (such as a plain woven fabric or a stockinette woven fabric) or a nonwoven fabric of synthetic fibers (for example, nylon or Tetron). Cloth base material 21
It is preferable that the wall thickness is usually 50 μm to 1 mm, but it is not limited to this.

Therefore, in addition to the planar heating elements shown in FIGS. 1 and 2, the planar heating element according to the present invention shown in FIGS. It has a configuration in which Therefore, the heating operation of the sheet heating element is essentially the same as that of the sheet heating element,
The use of planar heating elements, which will not be explained, is different from the use of planar heating elements, which requires an insulating polymer film, that is, an insulating layer 26.
Therefore, there is no risk of electrical leakage even if it comes into contact with surrounding components.

Next, with reference to FIGS. 3 and 4, a manufacturing method of a second embodiment of the sheet heating element according to the present invention will be described in detail.

After the first planar heating element shown in FIGS. 1 and 2 is prepared as described above, its surface, that is, the cloth base material 21. P
By forming an insulating layer 26 on the surfaces of the TC heating regions 22A, 22B and the electrodes 24, 25, a sheet heating layer according to the present invention is created.

Further, with reference to FIGS. 5 and 6, the structure and operation of a third embodiment of the planar heating element according to the present invention will be described in detail.

The recesses are planar heating elements according to the present invention, each having a PTC heating area (i.e., heating bond area with a positive temperature coefficient of electrical resistance) on at least one surface of the central portion of the cloth base material 32A.
, 32B are arranged, and a normal heat generating area (i.e. a heat generating area where the electrical resistance hardly changes when the temperature changes) is provided on both sides of both measurement parts of the cloth base material 31.
, 33C, 330 are arranged, and electrodes 34.3 are provided on the surfaces of the normal heating areas 33^, 33C, respectively.
5 are arranged.

The electrodes 34, 35 are connectable to a DC or AC power source (not shown).

The sheet heating element according to the present invention generates heat by substantially the same mechanism as the sheet heating element of the first embodiment described above.

In addition, with reference to FIGS. 7 and 8, the at and operation of the fourth embodiment of the sheet heating element according to the present invention will be described in detail.

42A is a planar heating element according to the present invention, and a PTC heating area (that is, a heating area where the temperature coefficient of electrical resistance is positive) is provided on at least one side of the central portion of the cloth base material 41.
, 42B are disposed on both sides of the cloth base material 31, and normal heat generation regions (i.e. heat generation regions whose electrical resistance hardly changes when temperature changes) 43A, 4:I8 are disposed on both sides of the cloth base material 31, and Electrodes 44 and 45 are arranged on the surfaces of regions 43^ and 43C, respectively.

The electrodes 44, 45 can be connected to a DC or AC power source (not shown).

An insulating polymer film layer, that is, an insulating layer 46 is disposed as a surface layer on the planar heating weight. That is, the cloth base material 41. PTC heat generating areas 42A, 428: normal heat generating areas 43A, 4:18 and portions of the electrodes 44.45 that form the outer surface are provided to avoid direct contact with peripheral members (not shown). An insulating polymer film layer, that is, an insulating layer 46 is disposed on the surface.

The cloth base material 41 is formed of a woven fabric (such as a plain woven fabric or a stockinette woven fabric) or a nonwoven fabric of synthetic fibers (for example, nylon or Tetron). Cloth base material 41
It is preferable that the wall thickness is usually 50 pm to 1 mm, but it is not limited to this.

Therefore, in addition to the planar heating element shown in FIGS. 5 and 6, the planar heating element according to the present invention shown in FIGS. 46. For this reason, the heating operation of the sheet heating element is substantially the same as that of the sheet heating element and the sheet heating element, and the sheet heating element, which requires no explanation, is Molecular film layer or insulating layer 4
6, there is no risk of electrical leakage even if it comes into contact with peripheral members.

Next, with reference to FIGS. 7 and 8, a manufacturing method of a fourth embodiment of the sheet heating element according to the present invention will be described in detail.

The surface of the planar fever rest created according to the third embodiment,
In turn, the cloth base material 31. PTC heating area 32A.

32B, normal heating area 3A, 338: 33
By disposing an insulating layer 46 on the surfaces of the heating element 0 and the electrodes 34 and 35, a sheet heating element according to the present invention is produced.

In addition, in order to better understand the planar heating element according to the present invention, specific numerical values will be given and explained.

Ethylene propyne rubber in the construction tsuba 1 too fflEk section and 20
Weight part of Ketchen Black EC and S ffi amount a
Zinc white ZnO; 1. s, ii stearic acid, t, s g tetramethylthiuram monosulfide, 0.5 parts by weight of tetramethylthiuram disulfide, and 2 parts by weight of sulfur in an oven roll mixer. A conductive elastomer composition was prepared by kneading the conductive elastomer composition.

Next, 83 parts by weight of carbon was added to 100 parts by weight of ethylene acrylic acid copolymer, which is a l:l copolymer of ethylene acrylate and acrylic acid, and
PTCm was prepared by kneading while heating to ℃.

The conductive elastomer composition and PTCjlit material are 8:
A PTC elastomer solution was prepared by dissolving and mixing the PTC elastomer solution into methyl ethyl ketone at a weight ratio of 2:2. P
The volume electrical resistance Rv of the TC elastomer changed as shown in FIG. 9 as the temperature T changed.

The PTC elastomer solution was made of Tetron nonwoven fabric (thickness 0.2
mm) by knife coating and drying.
PTC! Il product sheet high quality sheet PTC! [1 The composite sheet had a PTC heat generating layer with a wall thickness of 0.7 mm.

PTC! The il majesty sheet is 100 mm x 80 mm P.
It was cut into a TC heating region element body and used as a planar heating element element body.

Each side edge of the surface of the planar heating element element has a length of 20 mm.
A copper foil of mm x width 2 mm x thickness 0.05 mm is used as divided electrodes 14a to 14j; ISa to 15j of 6 mm.
10 divided electrodes 14a to 14j; 15a to 15j are vulcanized and bonded at intervals to form electrodes 14.15.
The adhesion length of each was 5 mm.

Through the above steps, a planar heat-generating suspension according to the present invention was created (see FIGS. 1 and 2).

The electrical resistance between the electrodes 14 and 15 of the planar heating element according to the present invention was 132Ω at room temperature of 20°C.

5 between the electrodes 14 and 15 of the sheet heating element IO according to the present invention
When an AC voltage of 50 volts was applied at 0 hertz and the temperature distribution was measured with an infrared thermotracer, the results were as shown in Figure 1O.

By arranging a vinyl sheet with a thickness of 0.2 mm as the insulating layer 26 on the surface of the sheet heating sheet produced in Example 1, the sheet heating element according to the present invention can be made. (See Figures 3 and 4).

The electrical resistance between the electrodes 24 and 25 of the planar heat generating circuit according to the present invention was 131Ω at room temperature of 20°C.

50 between the electrodes 24 and 25 of the planar heating suspension according to the present invention
When an AC voltage of 50 volts was applied and the temperature distribution was measured with an infrared thermotracer, the results were as shown in FIG.

(Example 3) Radius 5 was applied to the center of the surface of the PTC elastomer solution Tetron nonwoven fabric (thickness 0.2 mm) 31 prepared in Example 1.
PTC heat generating regions 32^ and 32B were formed by coating the film to a thickness of 0.7 mm and drying it.

By coating the conductive elastomer solution prepared in Example 1 to a width of 20 mm and a thickness of 0.7 mm on the Tetron nonwoven fabric 31 so as to be adjacent to both sides of the PTC heating regions 32A and 32B, and drying the first゜Second normal heat generating areas 3A, 33B, 33C, and 33D were formed.

The heat generating sheet created as above is 100mm x 80m.
The heating element was cut into a planar heating element element having a diameter of m, and a copper foil having a length of 100 mm, a width of 5 mm, and a thickness of 0.05 mm was vulcanized and bonded to each side edge as an electrode 14.35.

As a result, a planar heating element covering a shellfish was created (see Figures 3 and 4).

Electrode 34 having a planar heating structure according to the present invention. :15 was 128Ω at room temperature of 20°C.

Electrode 34 having a planar heating structure according to the present invention. :5 in 15
When an AC voltage of 50 volts was applied at 0 Hz and the temperature distribution was measured using an infrared thermotracer, the results were as shown in FIG.

(Example 4) A sheet heating structure according to the present invention was created by placing a vinyl sheet with a thickness of 0.2 mm on the surface of the heating sheet formed in Example 3 as an insulating layer 46. (See Figures 7 and 8).

The electrical resistance between the electrodes 44 and 45 of the planar heating device according to the present invention was 128Ω at room temperature of 20°C.

50 between the electrodes 44 and 45 of the planar heating structure according to the present invention
When an AC voltage of 50 volts was applied and the temperature distribution was measured with an infrared thermotracer, the results were as shown in FIG.

100 mm of PTC composition sheet prepared in Example 1
It was cut into a size of 80 mm x 80 mm to obtain a planar heating element element.

Copper foils having a length of 1 mm, a radius of 5 mm, and a thickness of 0.05 mm were vulcanized and bonded as electrodes to both sides of the surface of the planar heating element.

As described above, a planar heating element was prepared (see Fig. 14).

The electrical resistance between electrodes 14° and 15° of the sheet heating element is:
It was 128Ω at room temperature of 20°C.

An alternating current voltage of 50 volts at 50 Hz was applied between the electrode 14' in the form of a sheet heating element, and the temperature distribution was measured with an infrared thermotracer, as shown in FIG. 14.

(3) Effects of the Invention As is clear from the above description, the first planar heating element according to the present invention includes (a) a cloth base material, and (b) a PTC formed on at least one surface of the cloth base material. and heat generating areas.

(c) a first electrode consisting of a plurality of divided electrodes arranged for the PTC heat generating region; (d) a plurality of divided electrodes arranged for the PTC heat generating region apart from the first electrode; and a second electrode consisting of an electrode.

(i) It has the effect of suppressing the PTC heat generation area from becoming overheated and expanding along the electrode, and (ii) It has the effect of preventing the expansion of the overheating area and suppressing uneven temperature distribution. As a result, (iii) self-temperature control i! 1 function and an overheat prevention function.

Further, the second planar heating element according to the present invention includes (a) a cloth base material, (b) a PTC heat generation region formed on at least one surface of the cloth base material, and (C) a PTCi heat generation region formed on at least one surface of the cloth base material. The first. (d) A second normal heat generation area; The first. (iv) Even if the normal heating area becomes overheated and the overheating area expands along the electrode, it has the effect of preventing the PTC heating area from becoming overheated. However, it also has the effects (ii) and (iii) above.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a first embodiment of the sheet heating element according to the present invention, FIG. 2 is a sectional view taken along the line n-■ of the embodiment in FIG. FIG. 3 is a partially cutaway plan view showing a second example of such a sheet heating element. FIG. 4 shows the determination along the ff-IV line of the embodiment in FIG. 3. FIG. 5 is a plan view showing a third embodiment of the planar heating element according to the present invention, FIG. 6 is a sectional view taken along the line Vl-Vl of the embodiment in FIG. FIG. 8 is a partially cutaway plan view showing a fourth embodiment of such a sheet heating element, FIG. 8 is a sectional view taken along the line Vllll-Vllll of the embodiment in FIG. 7, and FIGS. 9 to 13 are according to the present invention. Explanatory diagram of operation of planar heating element, 1st
FIG. 4 is an explanatory diagram of a conventional example. 10.20, 30.40... Sheet heating element 11.21. :ll, 41・・・・・・・・・・
... Cloth base material 12A, 12B: 22A, 22B; 32A, 32B, 42A, 42B... PTC heat generating area 33A to 330.43A to 43D... Normal heat generating area 14, is, 24, 25° 34 .35, 44.45... Electrode 14a
~14j, ISa ~15j...-Divided electrode 24a
~24j, 25a~25j...Divided electrode 16.1
7,26.27・・・・・・・・・Connection line 28.
48・・・・・・・・・・・・・・・・・・Insulating layer patent applicant NOK Co., Ltd. agent Patent attorney Engineering # Takashi Otsutsu 1 picture prisoner ＼ lr , +510
Figure 2-＼ ノ) ++ 128) l
743B 41
428 43D Fig. 14---80°C -50'C

Claims (4)

[Claims] (1) (a) a cloth base material; (b) a PTC heat generating region formed on at least one surface of the cloth base material; and (c) a plurality of divided electrodes arranged for the PTC heat generating region. and (d) a second electrode consisting of a plurality of divided electrodes arranged at a distance from the first electrode with respect to the PTC heat generating region. shaped heating element. (2) A surface condition according to claim (1), characterized in that an insulating layer is formed on the outer surfaces of the cloth base material, the PTC heating region, and the first and second electrodes. heating element. (3) (a) a cloth base material; (b) a PTC heat generation region formed on at least one surface of the cloth base material; and (c) each arranged adjacent to both sides of the PTC heat generation region. (d) first and second electrodes disposed for the first and second normal heat generating areas, respectively. shaped heating element. (4) An insulating layer is formed on the outer surfaces of the cloth base material, the PTC heat generating region, the first and second normal heat generating regions, and the first and second electrodes. Range number (3)
The planar heating element described in .