JPH07211438A - Heater - Google Patents

Abstract

PURPOSE:To keep a heating element from moving so as to obtain a desired heat distribution by providing an injection molded inner layer inside the recessed portion of an outer layer which is also injection molded, and embedding a heater element, which comprises a heating element secured to a substrate, between the bottom surface of the recessed portion and the inner layer. CONSTITUTION:A saucer-shaped outer layer 1 having a raised periphery is injection molded from ABS resin or the like, and a heater element 3 whose size is almost same as the size of the bottom surface of a recessed portion 2 is fitted into the recessed portion 2, and the outer layer 1 is filled with an identical synthetic resin so as to integrate an inner layer 4 with the outer layer 1. The element 3 comprises a heating element 6 such as nichrome wire secured to a substrate 5 made of synthetic resin films, unwoven paper, heat-resistant paper, or the like, and is covered with polyethylene terephthalate or the like to provide an electrical insulating property. The element 3 is almost same size of the recessed portion 2 of the outer layer 1, and if the inner layer 4 is so thin that the area where it is fused integrally with the outer layer 1 is small, a plurality of through holes 8 are bored in the portion of the inner layer 4 where the heating element 6 is not provided, so that the area of fusion can be enlarged by the filling resin flowing into the holes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heater used when antifreeze of a liquid such as water, heat retention, water resistance and environment resistance not affected by gas are required.

[0002]

2. Description of the Related Art Since this type of heater is required to be formed in a shape corresponding to a mounting tool, a planar heater element is embedded in a cover body injection-molded with a synthetic resin. Moreover, it is a watertight structure. From the above, for example, the actual exploitation 63-
The technology disclosed in Japanese Patent Laid-Open No. 199699 is known, and the one disclosed in that publication is specifically a heating toilet seat.
In particular, as clearly shown in FIGS. 3 and 4, a concave surface layer is formed in a mold by injection molding, the surface layer is fitted into another mold, and the heater is placed in the concave portion of the surface layer. And place
In addition, the cords including the cords are temporarily fixed with an adhesive tape, and then the recesses of the surface layer are filled with the reinforcing layer by injection molding again, and the molding is performed by double injection molding with high pressure and low pressure.

[0003]

The structure of the heater according to the above publication is not described because it is not described, but since the means for temporarily fixing with an adhesive tape is described,
It is determined that the outer shape is elongated and the outer shape is set at a predetermined position. Also, in FIG. 5 of the publication, an example in which a heater is embedded in the central portion of the surface layer is seen. Even in the case of a toilet seat, a long heater is provided in a meandering shape to heat almost the entire upper surface of the surface layer. Is the ideal. However, if the heater is provided in a meandering shape, it takes time to temporarily fix it,
The larger the area of heat generation, the more labor required. Moreover, the tape is attached manually,
The arrangement is not uniform, and adjacent heater wires may come into contact with each other due to defective tape attachment, resulting in reliability problems.

The present invention is to solve the above problems, and to provide a heater having a structure capable of generating heat over almost the entire surface of a heater body which is watertight and which can be easily manufactured. is there.

[0005]

Means for Solving the Problems According to the solution of the present invention, an outer layer having a recess is made of a synthetic resin that is injection-moldable and has insulation and heat resistance, and the recess of the outer layer is made of the same synthetic resin as the outer layer. The inner layer formed by injection molding is provided so as to be in close contact with the outer layer, and a heater element having a heating element fixed to a substrate that can withstand the heat of injection molding is embedded between the bottom surface of the recess of the outer layer and the inner layer. To do.

Further, it is most preferable that the heating element of the heater element is a metal wire and is fixed to the substrate by sewing.

[0007]

The present invention is obtained by fitting a heater element into an injection-molded outer layer recess and then similarly injection-molding the inner layer into the recess. Particularly, in the present invention, the inner heater element fixes the heating element to the substrate. By using a heating element fixed to the entire surface of the substrate or according to a desired heat generation distribution, the heat generation distribution from the molded heater can be surely obtained in a desired state.

If a heating element made of a conductor of a heater element is sewn to a substrate, a pattern corresponding to the heat generation distribution can be freely manufactured, and the pattern does not collapse at the time of injection molding. It can be offered as an expensive product.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS To explain the present invention in detail, the examples shown in FIGS. 1 and 2 are flat plate heaters, and the outer layer 1 having a rectangular plate-like outer periphery is made of ABS resin or polypropylene. The outer layer 1 is injection-molded with a resin, and a heater element 3 having a size substantially equal to the size of the bottom surface of the recess 2 is fitted in the recess 2 formed by standing upright around the outer layer 1. The inner layer 4 is integrally provided with the outer layer 1 by injection molding again so that the recess 2 is filled with a synthetic resin of the same quality as the material of the outer layer 1 in a mold (not shown).

The heater element 2 comprises a substrate 5 and a heating element 6 fixed to it. Specifically, a synthetic resin film, a non-woven fabric or heat-resistant paper to be the substrate 5 is provided with a metal wire to be the heating element 6, specifically. Is a sewn nichrome wire with a sewing machine. In the figure, 7 indicates a sewing thread. Board 5
The material such as synthetic resin film, non-woven fabric or heat-resistant paper to be used may be one that can withstand the temperature at the time of injection molding the outer layer 1 and the inner layer 4 and has electrical insulation properties, such as polyethylene terephthalate (PET) and glass. Fiber is suitable.

Further, the heater element 3 is formed to have a size substantially equal to the size of the recess 2 of the outer layer 1 as described above, and the injection-molded inner layer 4 has a small thickness and is integrally fused to the outer layer 1. When the inner layer 4 has a small amount, a plurality of through holes 8 are provided in a portion of the substrate 5 that constitutes the heater element 3 where the heating element 6 is not provided. It is desirable to increase the fusion area with.

The cord 9 of the heater element 3 is
The inner layer 4 is projected from a window 10 provided at the same time as the injection molding, and after the molding, the window 10 is sealed by injecting a synthetic resin as a molding material 11.

Next, in the example shown in FIG. 3, the water pipe is formed to have a C-shaped cross section so as to cover the outer surface, and the heating element 6 is fixed to the outer layer 1, the inner layer 4 and the substrate 5 as in the above example. As shown in the figure, the outer layer 1 is on the outer side and the inner layer 4 is on the inner side. In addition, although not shown, the outer layer 1 is on the inner side and the inner layer 4 is on the outer side. You may. As shown in FIG. 3, when the outer layer 1 is on the outer side, a window hole 10 is provided in the outer layer 1, a cord 9 is passed through this hole, and a molding material 11 is used for sealing. Further, reference numeral 12 in the drawing denotes a fastening metal fitting, and by molding the outer layer 1 and the inner layer 4 with polypropylene resin, flexibility is obtained, and the fastening metal fitting 12 can be brought into close contact with, for example, the surface of a water pipe.

Due to the above structure, the heater element 3 in which the outer layer 1 is formed by injection molding in the mold to have the size of the concave portion 2 of the outer layer 1 and the heating element 6 is fixed to the substrate 5 is provided. It can be manufactured by fitting it in the recess 2, putting it in the mold again, and injection-molding the inner layer 4 in the recess 2.

When the heater is energized, heat is generated from the inner and outer layers 4, 1 according to the arrangement pattern of the heating elements 6 provided on the heater element. For example, the heating elements may be provided over the entire surface of the substrate. For example, heat is generated at a substantially uniform temperature from the entire surface of the outer layer 1 and the inner layer 4.

[0016]

According to the heater of the present invention, the inner layer, which is also filled by injection molding, is provided in the recess of the injection-molded outer layer, and the heater element having the heating element fixed to the substrate is embedded between the bottom surface of the recess and the inner layer of the outer layer. Since the heating element is fixed to the substrate, even if the inner layer is formed on the heater element fitted in the recess by the injection molding method,
The heating element does not shift due to the injection pressure, and heat is generated according to the heating elements arranged in a pattern according to the desired heat distribution. Moreover, it is needless to say that it is provided with a watertight structure because it is injection molded.

If a heating element made of a metal wire of a heater element is sewn to a substrate, a pattern according to the heat generation distribution can be freely manufactured, and the pattern does not collapse during injection molding, and reliability is improved. Can be provided as a high-quality product.

[Brief description of drawings]

FIG. 1 is a perspective view showing a heater according to the present invention.

FIG. 2 is a partially enlarged cross-sectional view of the same.

FIG. 3 is a perspective view showing a modified example of the heater according to the present invention.

[Explanation of symbols]

 1 Outer layer 2 Recessed portion 3 Heater element 4 Inner layer 5 Substrate 6 Heating element

Claims (2)

[Claims] 1. An outer layer (1) having a recess (2) is made of injection-moldable synthetic resin having insulation and heat resistance, and the recess (2) of the outer layer (1) has the same quality as the outer layer (1). The inner layer (4) formed by injection molding with the above synthetic resin is provided so as to be in close contact with the outer layer (1), and heat between the bottom surface of the concave portion (2) of the outer layer (1) and the inner layer (4) is not affected by injection molding heat. A heater characterized in that a heater element (3) having a heating element (6) fixed to a substrate (5) that can withstand is embedded. 2. The heater according to claim 1, wherein the heater element (3) has a heating element (6), which is a metal wire, fixed to the substrate (5) by sewing means.