JPS6129179Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to an improvement of a planar heating element, in which a plurality of circuits 2 stacked vertically via a heat-sensitive element body 1 are arranged longitudinally between the front and back insulating sheets 3. This relates to a planar heating element in which each circuit 2 is provided with a short circuit part 4 for each unit length, and the positions of the short circuit part 4 of one circuit 2 and the short circuit part 4 of the other circuit 2 are shifted. be.

Conventionally, for heating elements used in electric heating carpets, heating floors, etc., the planar heating element and the heating element were manufactured separately, and the edges of the heating element and the heating element were individually processed. In order to improve the quality and reduce the cost of the heating element, a long sheet heating element is formed by integrating a flat heating element and a heat-sensitive element, and the long sheet heating element is cut to an appropriate length. When used, it was difficult to process the end face of the circuit. In other words, when a long planar heating element is formed by integrating a heat-sensitive element body as shown in FIG. 3, and this planar heating element is cut to make a fixed-length heating element, for example, twice the unit length. , A to form a predetermined circuit on a sheet heating element of a fixed length.
It is necessary to cut the short-circuit part of part B and insulate the punched end face near the short-circuit part of part B, but as shown in the C-C cross section of Fig. 3 shown in Fig. If the circuits have exactly the same circuit pattern, the second
As is clear from the DD cross section in Figure 3, the insulation distance between the upper and lower circuits is maintained only by a thin heat-sensitive element body made of a plastic film such as polyamide film that has negative temperature resistance. There was a risk of a short circuit between the upper and lower circuits.

The present invention eliminates the above-mentioned drawbacks,
The purpose of this is to shift the positions of the short-circuit parts provided in the circuits stacked above and below through the heat-sensitive element body, so that even if the short-circuit part or the circuit near the short-circuit part is punched out, the punched upper and lower circuits will still remain the same. To provide a planar heating element whose end faces are not short-circuited and which can improve the quality and reduce the cost of the planar heating element by integrating the planar heating element and a heat-sensitive element body.

The present invention will be explained in detail below with reference to embodiments shown in FIGS. 3 to 8. A lower circuit 2a such as an electrode circuit is disposed on the upper surface of the back insulating sheet 3a made of synthetic resin such as vinyl chloride resin over almost the entire length in the longitudinal direction. The heat-sensitive element body 1, which is made of a polyamide film with a thickness of 30 to 100 μm and has a negative temperature resistance, is attached over almost the entire surface of the insulating sheet 3a. The upper circuit 2b is disposed, and an insulating sheet 3b on the front side is attached to the upper surface side of the upper circuit 2b to form a long planar heating element. The upper circuit 2b includes a linear portion 5a disposed on one side in the width direction of the heat-sensitive element body 1 over substantially the entire length in the longitudinal direction, and a linear portion 5a extending from a position close to the linear portion 5a to the other side of the heat-sensitive element body 1. A meandering portion 6 that is bent at a substantially right angle so as to meander across the
The meandering parts 6a, which are separated from each other in the longitudinal direction of the heat-sensitive element body 1, are electrically connected on the straight part 5a side, and both sides of each meandering part 6a and the straight part 5a are connected to each other.
is conductive at a substantially right angle at the short circuit part 4a, and the short circuit part 4a
On the left side in FIG. 3, wide portions 7a and 7b are provided on the linear portion 5a and the meandering portion 6a, respectively. The lower circuit 2a has approximately the same shape as the upper circuit 2b, but as shown in FIGS. 4 to 7, the short circuit part 4b is shifted to the right side in the figure from the short circuit part 4a, and the short circuit part 4b is On the left side, both the linear portion 5b and the meandering portion 6b are shifted to the outside of the linear portion 5a and the meandering portion 6b. Therefore, when cutting a long planar heating element in the width direction to form a fixed-length planar body,
As shown in Fig. 3, the wide part 7 side of the short circuit part 4a is
A planar heating element having a fixed length of 2 units is formed by cutting along the line and cutting the outside of the second wide width section 7 from the cut wide section 7 along the line FF. Next, as shown in FIGS. 4 to 6, the short-circuit parts 4a and 4b in the center of the planar heating element are punched out to form punched holes 8a and 8b, respectively, to form predetermined circuits 2a and 2b. Since the lower circuit 2a does not exist on the insulating sheet 3a side of 8a, and the upper circuit 2b does not exist on the insulating sheet 3b side of the punched hole 8b, the upper circuit 2b and the lower circuit 2a will not be short-circuited. Further, as shown in FIG. 7, the straight portions 5a, 5b and meandering portions 6a, 6b on the outside of the side short-circuit portions 4a, 4b are punched out to perform end face treatment, but as is clear from FIG. Since the lower circuit 2a does not exist on the insulation sheet 3a side of the punching hole 9a, and the upper circuit 2b does not exist on the insulation sheet 3b side of the punching hole 9b, the upper circuit 2b does not exist on the insulation sheet 3b side of the punching hole 9a.
This prevents short circuit between the lower circuit 2a and the lower circuit 2a.

As described above, the present invention includes a plurality of circuits stacked vertically via a heat-sensitive element body in the longitudinal direction between the front and back insulating sheets, and a short-circuit section is provided for each unit length of each circuit. Therefore, by forming a long planar heating element, cutting it into appropriate circuit unit lengths, and punching out the short-circuit parts at predetermined positions of each circuit, a heating circuit is formed. It is possible to obtain a planar heating element of a fixed length, and since the positions of the short-circuited part of one circuit and the short-circuited part of the other circuit in each of the upper and lower circuits are shifted, it is possible to The positions of the circuits can be shifted, and the insulation distance between the upper and lower circuits can be increased at the parts where the short-circuit parts of the upper and lower circuits are punched out, thereby preventing the end faces of the circuits from being short-circuited at this part. By integrating the planar heating element and the heat-sensitive element body, it is possible to improve the quality and reduce the cost of the planar heating element.

[Brief explanation of the drawing]

1 and 2 are longitudinal sectional views of a conventional example, FIG. 3 is a partially cutaway front view of an embodiment of the present invention, FIG. 4 is a partial enlarged sectional view of section A in FIG. 3, and FIG. Figures to 6th
The figures are a cross-sectional view taken along line X-X to Y-Y in FIG. 4, FIG. 7 is a partially enlarged front view of section B in FIG. 3, and FIG. 8 is a cross-sectional view taken along Z-Z in FIG. 1 is a heat-sensitive element body;
2 is a circuit, 3 is an insulating sheet, and 4 is a short circuit portion.

Claims (1)

[Scope of utility model registration request] A plurality of circuits are stacked vertically through heat-sensitive elements and are installed in the longitudinal direction between the front and back insulating sheets, and each circuit is provided with a short-circuit part for each unit length, and the short-circuit part of one circuit is connected to the short-circuit part of the other circuit. A sheet heating element made by shifting the position of the short-circuit part of the circuit.