JP2008108561A - Installation method of planar heating element and planar heating element unit - Google Patents

Abstract

Provided is a method for installing a planar heating element capable of greatly reducing generated electromagnetic waves without a significant increase in cost with a simple configuration.
A plurality of planar heating elements 10 are sequentially arranged so that only adjacent electrode lines 12 and 13 overlap between adjacent planar heating elements, and each of the overlapping electrode lines 12 and 13 includes: Electric power is applied to each planar heating element 10 so that currents with opposite polarities flow so that the generated electromagnetic waves cancel each other. When the planar heating elements are installed in this way, the electromagnetic waves generated from the overlapping electrode wires of the adjacent planar heating elements cancel each other, and the electromagnetic waves generated as a whole are nearly zero. Further, only the electrode wire portion is overlapped, and the heat generating portion is not overlapped, and the loss of the area of the heat generating portion, the thickness, and the weight are not significantly increased.
[Selection] Figure 3

Description

  The present invention relates to a method for installing a plurality of planar heating elements and a planar heating element unit having a plurality of planar heating elements, and in particular, a planar heating element capable of greatly reducing electromagnetic waves generated. The present invention relates to an installation method and a planar heating element unit.

In recent years, heat-generating parts (heat-generating elements) have been formed into a surface to melt snow on roofs and roads, to prevent snow melting and freezing at railroad crossings and track points, to heat, or to heat bedrock facilities and bedding. A planar heating element is used.
When an alternating current is used as a current applied to the heating element in the planar heating element, an electromagnetic wave is generated due to the alternating current. Although this electromagnetic wave is minute, such a planar heating element may be applied to a device that is used near a human body for a long time or a device that directly touches the human body, or may cause a malfunction due to the electromagnetic wave. When used in the vicinity of a certain device, it is desired to further reduce the generation of electromagnetic waves as much as possible.

As a general method for reducing electromagnetic waves generated from an alternating current, for example, a method of neutralizing an electromagnetic vector by twisting two electric wires such as electrode wires alternately is known. However, in the planar heating element having parallel electrodes, the electromagnetic wave has a characteristic that the power feeding side is strong and weakens toward the end, and the electromagnetic wave cannot be appropriately reduced by a simple wire twist method.
Thus, as a method of reducing electromagnetic waves from such a planar heating element, a method of superimposing two planar heating elements having the same dimensions and the same output has been proposed (for example, see Patent Document 1).
JP 2004-186038 A

  However, the method of stacking planar heating elements having the same dimensions and the same output requires twice as many planar heating elements as the same area, substantially more than double the cost, and the overall thickness and weight. Doubled and not practical.

The present invention has been made in view of such problems, and the object thereof is a planar heating element capable of greatly reducing generated electromagnetic waves without a significant increase in cost with a simple configuration. It is to provide an installation method.
Another object of the present invention is to provide a planar heating element unit that can significantly reduce electromagnetic waves generated without a significant increase in cost with a simple configuration.

  In order to achieve the above object, a method of installing a planar heating element according to the present invention includes a planar heating element having a pair of electrode wires and a heating part arranged in a planar shape between the pair of electrode wires. Are arranged side by side so that only the adjacent electrode lines overlap between the adjacent sheet heating elements, and electromagnetic waves generated are generated on each of the overlapping electrode lines of the adjacent sheet heating elements. It is characterized in that it is installed so that currents with opposite polarities only flow so as to cancel each other.

  With such a method of installing a planar heating element, the electromagnetic waves generated from the overlapping electrode wires of adjacent planar heating elements cancel each other, and as a whole, the generated electromagnetic waves have a strength close to substantially zero. . Further, only the electrode wire portion is overlapped, and the heat generating portion is not overlapped, and the loss of the area of the heat generating portion, or the significant increase in thickness and weight does not occur.

  Moreover, according to the planar heating element unit according to the present invention, the planar heating element unit includes a plurality of planar heating elements each having a pair of electrode wires and a heating portion disposed in a planar shape between the pair of electrode wires, The plurality of planar heating elements are sequentially arranged so that only the adjacent electrode lines overlap between the adjacent planar heating elements.

  In such a planar heating element unit, the electromagnetic waves generated from the overlapping electrode wires of the adjacent planar heating sections cancel each other, and the electromagnetic waves generated from the entire unit have a strength that is nearly zero. Further, only the electrode wire portions of the planar heat generating portion are overlapped, and the heat generating portions are not overlapped, and there is no significant loss in the area, thickness, or weight of the heat generating portion.

ADVANTAGE OF THE INVENTION According to this invention, the installation method of the planar heating element which can reduce significantly the electromagnetic waves to generate | occur | produce without making a significant cost increase with a simple structure can be provided.
In addition, it is possible to provide a planar heating element unit that can significantly reduce electromagnetic waves generated without a significant cost increase with a simple configuration.

An embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a main part plan view showing a structure of a planar heating element according to an embodiment of the present invention,
FIG. 2 is a cross-sectional view of an essential part taken along line II-II in FIG.
FIG. 3 is a view for explaining a method of installing the planar heating element according to the present invention,
FIG. 4 (A) is a diagram showing measured values of the intensity (magnetic flux density) of electromagnetic waves generated from the respective portions of the planar heating element arranged adjacent by the method according to the present invention,
FIG. 4B is a diagram showing the arrangement of the planar heating elements,
FIG. 5A is a diagram showing measured values of the intensity (magnetic flux density) of electromagnetic waves generated from each part of a single planar heating element for comparison,
FIG. 5B is a diagram showing the arrangement of the planar heating elements,
FIG. 6 (A) shows an electromagnetic wave generated from each part of a planar heating element unit that overlaps two planar heating elements for comparison and inputs an alternating current of opposite phase to the overlapping electrode band. Is a diagram showing the strength of
FIG. 6 (B) is a diagram showing the arrangement of the planar heating elements,
FIG. 7A shows an electromagnetic wave generated from each part of a planar heating element unit that overlaps two planar heating elements for comparison and inputs an alternating current of the same phase to the overlapping electrode band for comparison. Is a diagram showing the strength of
FIG. 7B is a diagram showing the arrangement of the planar heating elements.

First, the structure of the planar heating element according to the present embodiment will be described with reference to FIGS. 1 and 2.
There are various types of planar heating elements, but the planar heating element used in the present embodiment is a parallel electrode type planar heating element, and is linear between a pair of electrodes arranged in parallel. This is a linear surface type heating element in which heating elements are arranged in parallel.
The planar heating element 10 is a thin plate-like member having a rectangular planar shape, two electrode strips 12 and 13 (first electrode strip 12 and second electrode strip 13) arranged in parallel, and a heat generating portion. 14, a lead wire 22 and an insulating coating layer 30. More specifically, as shown in FIG. 2, a woven fabric 15 having a weft 16 and a warp 17 is sandwiched between the insulating coating layers 30, 30 to constitute the main part thereof.

  The weft 16 of the woven fabric 15 is composed of a conductive yarn for heat generation and a yarn including an insulating yarn as required. The heat-generating conductive yarn constituting the weft 16 is, for example, one in which the outer periphery of an insulating filament is covered with a conductive paint. The heat generating conductive yarn may be a single wire or a stranded wire. The material of the insulating filament is not particularly limited, and examples thereof include polyester, cotton, nylon, and glass fiber. As the conductive paint, for example, a positive temperature characteristic (PTC) type conductive paint having a high temperature dependency obtained by mixing conductive particles is used.

The PTC-type conductive coating is not particularly limited as long as the resistance increases as the temperature increases, and a good self-temperature control function is exhibited. For example, metal particles, carbon particles (carbon black particles, graphite carbon) Particles, graphite particles) and the like containing conductive particles are used. As the conductive particles, carbon particles are preferably used.
If an insulating filament is immersed in such a conductive paint and dried, the conductive yarn constituting the weft 16 of this embodiment can be obtained. The electric resistance value of the conductive yarn is, for example, about 500 to 10,000 Ω / cm.

The warp yarns 17 of the woven fabric 15 are made of insulating yarns, extend along the longitudinal direction L (see FIG. 1) of the planar heating element 10, and are predetermined along the width direction W perpendicular to the longitudinal direction L. Arranged at intervals.
The insulating yarn constituting the warp yarn 17 is composed of an insulating filament used as a core material of a conductive yarn, for example, except that the warp yarn 17 is not coated with a conductive paint, or a metal wire that is insulated and coated, for example. The The warp yarn 17 may also be a single wire or a stranded wire.

A pair of electrode strips (sometimes referred to as electrode wires) 12 and 13 are arranged along the longitudinal direction L of the woven fabric 15 at both ends in the width direction W of the weft 16. The first electrode strip 12 and the second electrode strip 13 are each composed of a plurality of conductive lines. For example, the electrode strips 12 and 13 are each configured by connecting a plurality of conductive wires in a honeycomb shape (not shown) and connecting them in the width direction W. The conductive wires constituting the electrode strips 12 and 13 are preferably metal yarns such as copper, iron, and stainless steel, and the metal yarns may be single wires or stranded wires.
As shown in FIG. 2, the electrode wires 12 and 13 are knitted integrally with the woven fabric 15 at both ends of the woven fabric 15 and are electrically connected to the respective wefts 16.

In this embodiment, the space | interval L1 (refer FIG. 1) between the adjacent wefts 16 in the woven fabric 15 is 0.01-50 mm, for example. Moreover, the space | interval W1 between the adjacent warp yarns 17 in the woven fabric 15 is 0.01-50 mm, for example.
If the arrangement interval L1 of the weft yarns 16 is too narrow, the amount of heat generated per unit area tends to be too large, and if the arrangement interval L1 of the weft yarns 16 is too wide, the heat generation capacity of the entire planar heating element tends to decrease. is there. Further, since the warp yarn 17 hardly contributes to heat generation, the arrangement interval W1 of the warp yarn 17 can be made wider than the arrangement interval L1 of the weft yarn 16 as long as the strength as the woven fabric 15 can be maintained. However, considering the workability of forming the woven fabric 15 of the weft 16 and the warp 17, the weft arrangement interval W1 and the warp arrangement interval L1 should be substantially the same.

  Further, the wire diameters of the weft 16 and the warp 17 and the wire diameters of the metal yarns when the electrode bands 12 and 13 are made of metal yarns are substantially the same, for example, 10 to 1000 μm.

  As shown in FIG. 2, the woven fabric 15 including the electrode strips 12 and 13, the weft 16, and the warp 17 is covered with a transparent or opaque insulating coating layer 30. The insulating coating layer 30 is not particularly limited, and is formed of, for example, a vinyl chloride sheet, a polyethylene terephthalate (PET) sheet, a polyolefin sheet, a polyurethane sheet, an acrylic sheet, or the like.

The method for coating the woven fabric 15 with the insulating coating layer 30 is not particularly limited, and examples thereof include a method using an adhesive and a method using thermal fusion. When an adhesive is used, a polyurethane or epoxy resin adhesive is preferably used as the adhesive.
In addition, the insulating coating layer 30 of the planar heating element 10 in the above-described embodiment may be a single layer film, but may be composed of a multilayer film of, for example, a vinyl chloride sheet and a polyethylene terephthalate (PET) sheet. When this insulating coating layer 30 is composed of a multilayer film of a vinyl chloride sheet and a PET sheet, it is preferable that the inside is composed of a vinyl chloride sheet and the outside is composed of a PET sheet. By disposing the PET sheet on the outside, it is possible to effectively prevent the penetration of liquid from the outside. In addition, by arranging a relatively flexible vinyl chloride sheet on the inner side, it becomes easy to heat-seal with a woven fabric serving as a heating element, and damage to the outer PET sheet can be prevented. Can be compensated with. The multilayer film can be manufactured by, for example, a thermal lamination method.

  A lead wire 22 for connecting to an AC power source is connected to one end portion in the longitudinal direction L of each of the electrode strips 12 and 13. As the AC power supply, a commercial AC power supply of 100 to 200 V is usually used at 50 Hz or 60 Hz.

  In the planar heating element 10 having such a configuration, when a predetermined alternating current flows between the electrode strips 12 and 13 via the lead wire 22, a current flows in the longitudinal direction W of the weft 16, and the weft 16 Generates heat. Accordingly, the inner region of the electrode strips 12 and 13 becomes the heat generating portion 14 of the sheet heating element 10. The heating temperature of the heating section 14 in the planar heating element 10 is preferably about 80 ° C. or less, although it depends on the material of the insulating coating layer 30. The heat generation temperature can be adjusted by adjusting the resistance value between the electrode bands and the voltage to be used.

  Next, a method of configuring the planar heating element unit 1 by arranging a plurality of planar heating elements 10 having the above-described configuration by the planar heating element installation method according to the present invention will be described.

First, when the planar heating element unit 1 is configured by arranging a plurality of planar heating elements 10, as shown in FIG. 3, the electrode strips 12 and 13 are overlapped between adjacent planar heating elements 10. Place some of them in layers.
In more detail in the example shown in FIG. 3, the first of the second sheet heating element _10-2 adjacent thereto and the second electrode strip 13 _-1 of the first sheet-like heating element 10 _-1 The electrode strip _12-2 is overlaid. Also, superimposed and third planar heating element ₁₀ first _-3 electrode strips _{12 -3} adjacent thereto and the second electrode strip _{13 -2} second planar heat generating element _{10 -2} . Similarly, the second electrode strip 13 _-n of the nth planar heating element 10 _-n and the (n + 1) th first electrode strip 12- _{(n + 1)} are overlapped to form a plurality of planar shapes. The heating elements 10 are sequentially arranged.

  By sequentially arranging and connecting the plurality of planar heating elements 10 in this way, as shown in FIG. 3, the peripheral portions where the electrode bands 12 and 13 of the planar heating elements 10 are formed are sequentially overlapped. The planar heating element unit 1 having a plurality of planar heating elements 10 is configured in such a manner that most of the heating sections 14 of each planar heating element 10 are arranged independently without being superposed. It is formed.

And an alternating current is input with respect to a series of planar heating element 10 arrange | positioned in this way as follows. In other words, it superimposed second electrode zone ₁₃ of the planar heating element _{10 -n} of the n and _-n and the (n + 1) sheet heating element _{10 - (n + 1)} first electrode strip ₁₂ of _{- (n + 1 )} , An alternating current is input to each planar heating element 10 so that an alternating current with an opposite phase, that is, an alternating current with the same absolute value and opposite polarity flows.

In other words, when a current of a predetermined value in a predetermined direction (a positive direction) flows through the second electrode strip 13 _-n of the n-th planar heating element 10 _-n , it is superimposed on this. The (n + 1) -th first electrode strips 12- _{(n + 1)} are supplied to each of the series of planar heating elements 10 so that currents of the same value in the opposite direction (− direction) flow. To input an alternating current of a predetermined phase. For this purpose, for example, the electrode strips 12 _-i and 13 _-i (i = 1, 2,...) Of each of the series of planar heating elements 10 are respectively connected to the output terminals of the same AC power source. What is necessary is just to connect so that electrode strip 12- _i and electrode strip 13- _i may become opposite.
Note that the characteristics of the current flowing through the first electrode strip 12 and the second electrode strip 13 of each planar heating element 10 are in accordance with the characteristics of the power applied to the planar heating element 10, and the planar heating element. There is no difference between the first electrode strip 12 and the second electrode strip 13 as the structure of FIG. However, in the following description, it is assumed that desired power is applied to each planar heating element 10 from the outside so that currents in opposite phases flow through the first electrode strip 12 and the second electrode strip 13. The first electrode strip 12 and the second electrode strip 13 are used separately.

As a result, the electromagnetic waves generated from the superimposed electrode bands, that is, the electromagnetic waves generated by the current flowing in the second electrode band 13 _-n of the nth planar heating element 10 _-n are superimposed on this. The electromagnetic wave generated by the current flowing through the (n + 1) th first electrode band 12- _{(n + 1)} is an electromagnetic wave having the same strength but the opposite polarity. As a result, these electromagnetic waves cancel each other, and the electromagnetic waves generated from the planar heating element unit 1 are greatly reduced.

As described above, according to the planar heating element 10 of the present embodiment, when the plurality of planar heating elements 10 are arranged, the first electrode strip 12 of the planar heating element 10 and another planar condition adjacent thereto are provided. Since the second electrode band 13 of the heating element 10 is superposed, and currents having opposite phases are input to the first electrode band 12 and the second electrode band 13, The generated electromagnetic waves cancel each other, and the intensity of the electromagnetic waves generated from the entire sheet heating element 10 can be suppressed to a very low level.
As a result, it is possible to easily install a plurality of planar heating elements while greatly reducing the generated electromagnetic waves without increasing the cost. In addition, it is possible to provide a planar heating element unit that can significantly reduce electromagnetic waves generated without a significant cost increase with a simple configuration.

In the planar heating element unit 1 according to this embodiment in which a plurality of planar heating elements 10 are arranged in such a configuration, the fact that the emitted electromagnetic waves are greatly reduced will be described using actual measurement results. To do.
Here, while showing the measured value of the electromagnetic wave radiate | emitted from the planar heating element unit 1 which concerns on this embodiment, as a comparative example, the measured value of the electromagnetic wave radiate | emitted from the planar heating element 10 single-piece | unit, 2 sheet-like shape The measured value of the electromagnetic wave emitted when an alternating current of opposite phase is input to the overlapping electrode band and the two heating elements are completely overlapped and overlapped with the overlapping electrode band. The measured value of the electromagnetic wave emitted when a phase alternating current is input is shown.

  In addition, the measurement of electromagnetic waves measures the magnetic flux density of a predetermined | prescribed measurement point when 50Hz and 100V alternating current power is applied to each planar heating element 10 using the EMF-822A measuring instrument by a Teston Co., Ltd. By doing. The measurement points are the width direction W of the sheet heating element 10 (see FIG. 1), that is, a predetermined plurality of positions in the direction in which the sheet heating elements 10 are arranged, and the longitudinal direction L of the sheet heating element 10 (see FIG. 1). ) As a measurement position, and a point 1 cm away from the surface of the planar heating element 10 at the measurement position vertically (directly above) as a measurement point.

  The planar heating element used for the measurement here has a distance (center-to-center distance) between the first electrode band 12 and the second electrode band 13 of 74 cm in the width direction W (FIG. 1), and the longitudinal direction. L (FIG. 1) is a planar heating element 10 in which the length of the electrode bands 12 and 13 from the feeding position (position where the electrode bands 12 and 13 and the lead wire 22 are connected) is 80 cm or more. Yes, the same planar heating element 10 is used in each example and comparative example.

Table 1 shows the intensity (magnetic flux density) of electromagnetic waves generated from the vicinity of the connection portion between two adjacent sheet heating elements 10 _-1 and 10 _{-2 in} the sheet heating element unit 1 according to this embodiment. 4A is a graph showing the measured values, and FIG. 4B is a diagram showing two planar heating elements 10 ₋₁ , It is the figure which showed arrangement _| positioning of _10-2 .

In this measurement, the planar heating element ₁₀ -1, (see FIG. 4 (B)) in the width direction W of _10-2, the first sheet of the planar heat generating element _{10 -1} second electrode strip 13 _{- 1} and the first electrode strip _12-2 and are superimposed position of the second sheet of the planar heat generating element _10-2 (electrode position) as a reference, each of the planar heating element ₁₀ -1 from the reference position, 10 _-2 directions (first sheet heating element _10-1 direction (-direction) and second sheet heating element 10 _-2 direction (+ direction)) 10 cm apart and each position until 30 cm away Is the measurement position. Further, in the longitudinal direction L of the planar heating elements 10 ₋₁ and 10 ₋₂ , each position up to 80 cm away from the feeding position by 20 cm is set as a sample position (measurement position).

Each measurement position in the width direction W defined by the distance from the position (reference position) of the electrode wires 13 _-1 and 12 _-2 and each measurement position in the longitudinal direction L defined by the sample length from the feeding position. Table 1 shows the measurement results of the magnetic flux density at the lattice points. FIG. 4A shows a three-dimensional graph with the measured magnetic flux density as the vertical axis. Incidentally, although not shown, electrode strips _{12 -1} and _{12 -2} are connected to the same output terminal of the AC power source, the electrode strips _{13 -1} and _{13 -2,} the AC power source identical to the AC power source Are connected to an output terminal opposite to the output terminal.

  Table 2 is a table showing measured values of the intensity (magnetic flux density) of electromagnetic waves generated from each part of the single planar heating element 10 for comparison, and FIG. 5A shows the measured values. FIG. 5 (B) is a diagram showing a single sheet heating element 10 for easy understanding.

  In this measurement, in the width direction W of the sheet heating element 10 (see FIG. 5B), the position of the first electrode line 12 is used as a reference, and the first electrode line in the direction of the second electrode line 13 is used. The distance from 12 is 0 cm (0 cm = position of the first electrode line 12), 2 cm, 7 cm, 17 cm, 27 cm, 37 cm, 47 cm, 57 cm, 67 cm, 72 cm and 74 cm (74 cm = position of the second electrode line 13) In the longitudinal direction L of the planar heating element 10, each position up to 80 cm away from the power feeding position is set as a sample position (measurement position).

  Table 2 shows the measurement results of the magnetic flux density at the lattice points at the respective measurement positions in the width direction W and the longitudinal direction L of the planar heating element 10. FIG. 5A shows a three-dimensional graph with the measured magnetic flux density as the vertical axis.

Table 3 also shows that for comparison, the two sheet heating elements 10 _-1 and 10 _-2 are overlapped, and the overlapping electrode bands 13 _-1 and 12 _-2 and 12 _-1 and 13 _-2 are overlapped. In other words, two sheets of sheet heat are generated so that electrode bands 13 _-1 and 12 _-2 and 12 _-1 and 13 _-2 through which an alternating current of opposite phase flows are overlapped with each other. FIG. 6A is a table showing measured values of the intensity (magnetic flux density) of electromagnetic waves generated from a planar heating element unit of a conventional form in which the entire bodies 10 ₋₁ and 10 ₋₂ are overlapped. FIG. 6B is a diagram showing the arrangement of the two sheet heating elements 10 ₋₁ and 10 ₋₂ for easy understanding.

In this measurement, in the width direction W of the planar heating elements 10 _-1 and 10 _-2 (see FIG. 6B), the first electrode wire 12 _-1 of the first planar heating element 10 _-1 is used. the distance from the second electrode line 13 _-2 and are superimposed position as a reference (reference position), each reference position to the other electrode line direction of the second sheet-like heating element 10 _-2 0 cm (0 cm = electrode lines _{12 -1} and the electrode line _{13 -2} and is superimposed position), 2cm, 7cm, 17cm, 27cm, 37cm, 47cm, 57cm, 67cm, 72cm and 74cm (74cm = electrode lines _{13 -1} and the electrode wire 12 ₋₂ is a measurement position, and in the longitudinal direction L of the planar heating elements 10 ₋₁ and 10 ₋₂ , each distance of 20 cm from the power feeding position to 80 cm. Position the sample position (measurement position) That.

Table 3 shows the measurement results of the magnetic flux density at the lattice points at the respective measurement positions in the width direction W and the longitudinal direction L of these planar heating elements 10 _-1 and 10 _-2 . Further, FIG. 6A shows a three-dimensional graph with the measured magnetic flux density as the vertical axis.

Further, Table 4 shows that for comparison, the two planar heating elements 10 _-1 and 10 _-2 are overlapped, and the overlapping electrode bands 12 _-1 and 12 _-2 and 13 _-1 and 13 _-2 are overlapped. In other words, two sheets of sheet heat are generated so that the electrode bands 12 _-1 and 12 _-2 and 13 _-1 and 13 _-2 through which the alternating current of the same phase flows are overlapped with each other. FIG. 7A is a table showing measured values of the intensity (magnetic flux density) of electromagnetic waves generated from the planar heating element unit in which the entire bodies 10 ₋₁ and 10 ₋₂ are superposed. FIG. 7B is a diagram showing the arrangement of the two sheet heating elements 10 ₋₁ and 10 ₋₂ for easy understanding.

In this measurement, in the width direction W of the planar heating elements 10 _-1 and 10 _-2 (see FIG. 7B), the first electrode wire 12 _-1 of the first planar heating element 10 _-1 is used. And the first electrode line 12 _{-2 of} the second planar heating element 10 _-2 as a reference (reference position), and the distance from the reference position in the direction of the other electrode line is 0 cm (0 cm) = electrode lines _{12 -1} and the electrode line _12-2 and is superimposed position), 2cm, 7cm, 17cm, 27cm, 37cm, 47cm, 57cm, 67cm, 72cm and 74cm (74cm = electrode lines _{13 -1} and the electrode wire 13 each position is _-2 and is superimposed position) as a measurement position, also the planar heating element ₁₀ -1, in the longitudinal direction L of _10-2, each of up to 80cm away from the feed point by 20cm Position the sample position (measurement position) That.

Table 4 shows the measurement results of the magnetic flux density at the lattice points at the respective measurement positions in the width direction W and the longitudinal direction L of these planar heating elements 10 _-1 and 10 _-2 . FIG. 7A shows a three-dimensional graph with the measured magnetic flux density as the vertical axis.

  As can be seen from Tables 1 to 4 and FIGS. 4 (A) to 7 (A), in the sheet heating element 10 alone, as shown in Table 2, FIGS. 5 (A) and 5 (B), Very strong electromagnetic waves having a magnetic flux density of 12.30 Tesla are generated above the first electrode strip 12 and the second electrode strip 13, respectively.

On the other hand, the two planar heating elements 10 _-1 and 10 _-2 are completely overlapped, and currents of opposite phases are passed through the overlapping electrode wires 12 _-1 and 13 _-2 and 13 _-1 and 12 _-2 respectively. As shown in Table 3, FIG. 6 (A) and FIG. 6 (B), the intensity of electromagnetic waves generated is significantly reduced compared to the case of the planar heating element 10 alone, also in the upper part of the strongest electrode lines, maximum 1.62 Tesla at the top of the electrode lines _{12 -1} and _{13 -2,} and it has a maximum 2.43 Tesla at the top of the electrode lines _{13 -1} and _{12 -2.}
However, even in this arrangement, the electromagnetic waves are stronger in the upper part of the electrode wires 12 _-1 and 13 _-2 or in the upper part of the electrode wires 13 _-1 and 12 _-2 than in other positions. Some electromagnetic waves are generated.

The two sheet heating elements 10 _-1 and 10 _-2 were completely overlapped, and currents having the same phase were supplied to the overlapping electrode wires 12 _-1 and 12 _-2 and 13 _-1 and 13 _-2 respectively. In this case, as shown in Table 4, FIG. 7 (A) and FIG. 7 (B), the intensity of the generated electromagnetic wave is greatly increased as compared with the case of the sheet heating element 10 alone, electrode lines _{12 -1} and _{13 -2} upper and electrode lines _{13 -1} to ₁₂ top both _-2, has become a very large value and a maximum 19.90 Tesla.

In contrast, only the electrode lines are sequentially overlapped by the adjacent planar heating elements 10 ₋₁ and 10 ₋₂ , and overlapped electrode lines (electrode lines 13 ₋₁ and 12 ₋₂ and 12 ₋₁ and 13 ₋₂ ) are overlapped. In the arrangement according to the present invention in which the current of opposite phase is applied, as shown in Table 1, FIG. 4 (A) and FIG. 4 (B), in the case of a planar heating element alone (Table 2, FIG. 5 (A) and FIG. 5 (B)), and when two sheet-like heating elements are completely overlapped and an anti-phase current is passed through the overlapping electrode wires (Table 3, FIG. 6 (A) and FIG. 6). Compared with (B)), the intensity of the generated electromagnetic wave is greatly reduced.
In particular, as is apparent from Table 1 and FIG. 4A, no particularly strong electromagnetic wave is observed at the upper part of the electrode wire, and a magnetic flux density of approximately 0.03 terraces and a magnetic flux density close to zero at the maximum. It has become. From this, it can be seen that such an arrangement according to the present invention effectively cancels the electromagnetic waves generated in the superimposed electrode bands.

  As described above, according to the planar heating element 10 of the present embodiment, when the plurality of planar heating elements 10 are arranged, the adjacent electrode bands 12 and 13 of the adjacent planar heating elements 10 are overlapped. Since power is applied to each planar heating element 10 so that currents in opposite phases flow through the overlapped electrode bands, the electromagnetic waves generated from the electrode bands cancel each other, The intensity of the electromagnetic wave generated as a whole of the heating element 10 can be suppressed to a very low level.

  Further, the adjacent sheet heating elements 10 overlap with each other only in the electrode band, and the heating part 14 does not overlap. Therefore, the planar heating element 10 can be used effectively, and the state where the cost is remarkably increased or the weight is doubled can be prevented.

  The planar heating element 10 according to the present embodiment is a so-called linear surface type heating element of a parallel electrode type. Therefore, even if a part of the planar heating element is damaged and a part of the linear heating element composed of the weft 16 is cut, a current is supplied to the other weft 16 to maintain the heat generation. it can. Further, the cut weft 16 does not generate heat because no current flows, the voltage applied to the other weft 16 does not change, and there is no possibility of abnormal heat generation.

  The present invention is not limited to the above-described embodiment, and can be variously modified within the scope of the present invention.

  For example, in the above-described embodiments, the present invention has been described using a linear surface type heating element, but the present invention is not limited to the case where a linear surface type heating element is used. For example, the present invention can be similarly applied to a planar heating element of a pure planar type in which a heating element made of a planar conductive film or the like is disposed between electrodes.

FIG. 1 is a main part plan view showing the structure of a planar heating element according to one embodiment of the present invention. FIG. 2 is a cross-sectional view of an essential part taken along line II-II in FIG. FIG. 3 is a view for explaining a method of installing the planar heating element according to the present invention. FIG. 4 (A) is a diagram showing measured values of the intensity (magnetic flux density) of electromagnetic waves generated from the respective portions of the planar heating element arranged adjacent by the method according to the present invention, and FIG. It is a figure which shows arrangement | positioning of the planar heating element. FIG. 5A is a diagram showing measured values of the strength (magnetic flux density) of electromagnetic waves generated from each part of a single sheet heating element for comparison, and FIG. It is a figure which shows arrangement | positioning of a heat generating body. FIG. 6 (A) shows an electromagnetic wave generated from each part of a planar heating element unit that overlaps two planar heating elements for comparison and inputs an alternating current of opposite phase to the overlapping electrode band. FIG. 6B is a diagram showing the arrangement of the planar heating elements. FIG. 7A shows an electromagnetic wave generated from each part of a planar heating element unit that overlaps two planar heating elements for comparison and inputs an alternating current of the same phase to the overlapping electrode band for comparison. FIG. 7B is a diagram showing the arrangement of the planar heating elements.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Planar heating element unit 10 ... Planar heating element 12 ... 1st electrode belt | band | zone (electrode wire)
13 ... Second electrode band (electrode wire)
DESCRIPTION OF SYMBOLS 14 ... Heat generating part 15 ... Woven cloth 16 ... Weft 17 ... Warp 22 ... Lead wire 30 ... Insulation coating layer

Claims (2)

  A plurality of planar heating elements each having a pair of electrode wires and a heating portion formed in a planar shape between the pair of electrode wires are arranged so that only the electrode wires adjacent between the adjacent planar heating elements are They are arranged side by side so as to overlap each other, and each of the overlapping electrode lines of the adjacent planar heating elements is installed so that currents having opposite phases only flow so that generated electromagnetic waves cancel each other. An installation method of a planar heating element characterized by the above. A plurality of planar heating elements having a pair of electrode wires and a heating part formed in a planar shape between the pair of electrode wires,
The planar heating element unit, wherein the plurality of planar heating elements are sequentially arranged so that only the adjacent electrode wires overlap between the adjacent planar heating elements.

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