JPH0240885A - Plate type heating unit - Google Patents

Abstract

PURPOSE:To improve a heat supply effect of far infrared rays by providing a ceramic layer on a radiation surface so as to enhance far infrared rays radiation characteristics. CONSTITUTION:A plate type exothermic body H is equipped, in its inside, with an inorganic plate type forming body 1 which generates a heat when power is applied, and at the same time a ceramic layer 2 is provided on a radiation surface. The ceramic layer 2 is utilized for radiating a far infrared ray effectively, and the far infrared rays, in this case, an infrared ray with its wave length of about 4mum or more. In the mean time, the thickness of the ceramic layer 2 is, for example, 2-200mum in the case of a coat layer, while it is normally 30-50mum, but for a sheet layer, it is thicker than those. Consequently, men, animals and plants, etc., can receive an effective hat supply accompanied by infrared ray radiation.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a plate-shaped heating element used for heating and the like.

[Conventional technology]

As a plate-shaped heating element used for heating, etc., a molded body made by dispersing conductive materials such as carbon fiber or carbon blank in an inorganic material made of cement mixed with aggregate such as silica sand or coal ash, and molding this into a plate shape. Some molded products are equipped with a molded body that generates heat when energized.

[Problem to be solved by the invention]

The above-mentioned plate-shaped heating elements have been installed, for example, on the back side of a decorative panel on the floor surface, and used to heat the room by supplying the heat generated in the molded body from the floor to the room through conduction and convection. There is. However, in terms of heat supply function, there is no particular difference from other heating devices, so in order to expand the use of the same plate-shaped heating element, a major challenge is to provide it with more effective functions. There is.

In view of the above circumstances, it is an object of the present invention to provide a plate-shaped heating element having a more effective heat supply function.

[Means to solve the problem]

In order to solve the above problem, the inventors, after various studies, discovered the effects of far-infrared rays in the long wavelength range (wavelength range of about 4 μm or more) that exceeds the near-infrared range on humans, animals, and plants. I paid attention. In recent years, the effectiveness of far infrared rays emitted from radiators at temperatures around room temperature has often been talked about, but the reason far infrared rays have such special benefits is that they penetrate deep into the human body. It is said that this is because it has the effect of In particular, wavelengths of 7 to 14 μm are said to provide a warm sensation to the human body.

Then, we conducted a deeper study and found that if the heat dissipation surface of the plate-shaped heating element could efficiently radiate far-infrared rays,
We were able to complete this invention by obtaining the knowledge that far-infrared rays can have a heat supply function that combines the special effects of infrared rays.

Therefore, in the plate-shaped heating element according to the present invention, a ceramic layer is provided on the heat radiation surface to improve far-infrared radiation characteristics.

[For production]

In the plate-shaped heating element of the present invention, heat generated in the inorganic plate-shaped molded body is transmitted to the ceramic layer on the heat radiation surface. The ceramic layer is
It has the property of efficiently emitting far-infrared rays. A portion of the heat from the inorganic plate-shaped molded body is sufficiently radiated as infrared rays in the far-infrared region.

It goes without saying that some heat is released from the ceramic layer by conduction and convection. Of course, the emitted far infrared rays play a part in the heat supply function, so the provision of the ceramic layer does not impair the heat supply function.

〔Example〕

Hereinafter, one embodiment of the plate-shaped heating element according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the plate-shaped heating element according to the present invention. FIG. 2 shows the structure around the inorganic plate-shaped molded body of this plate-shaped heating element, and FIG. 3 shows the state in which the plate-shaped heating element is used.

The plate-shaped heating element H includes an inorganic plate-shaped molded body l that generates heat when energized inside, and a ceramic layer 2 is provided on the heat dissipation surface. A heat insulating material 3 is provided on the back surface of the inorganic plate-shaped molded body 1, and the molded body 1 and the heat insulating material 3 are connected to a covered (cover) material 4.
covered with. The ceramic layer 2 is provided on the heat radiation side surface of the coating material 4.

The inorganic plate-shaped molded body 1 is made by mixing and dispersing a conductive material 10 such as carbon fiber, carbon black, or metal powder into an inorganic material that is a combination of cement and aggregate such as silica sand or coal ash. is formed into a plate shape as shown in Figure 2. When using carbon fibers, the carbon fibers are coated with a conductive resin to prevent oxidation. Conductive material 10
, the plate-shaped molded body l has a certain level of conductivity.

Specifically, the molded body 1 is made of, for example, an inorganic material with a water-cement ratio of 90% by volume and a silica sand/cement ratio of 1.3, in which carbon fiber and carbon black are each added at 0.5%. ~4% by volume, 2-10
14 by mixing the mixture in a proportion of % by volume and molding it into a plate of a desired size. If the amount of carbon fiber mixed is less than 0.5% by volume, sufficient impact resistance and cracking resistance will not be achieved, while if it exceeds 4% by volume, it will not be uniformly dispersed depending on kneading. Moreover, the cost increases.Furthermore, the carbon blank is used to adjust the total amount of carbon in the molded body 1 to obtain a predetermined calorific value, and the amount is determined by taking into account the amount of carbon fiber. Further, the thickness of the molded body 1, which is mixed with a carbon blank so that the desired amount of heat can be obtained no matter which direction the current is applied, is usually about 5 to 20 mm. If it is too thin, the heat capacity will become too large even though the strength increases, and the temperature increase rate will slow down.If it is too thin, the temperature increase rate will increase, but the strength will not be sufficient.

For example, when a commercial voltage of 100V is applied between the electrodes 5.5, the above-mentioned molded body l exhibits a characteristic of 300w/n (approximately 300w/n) and a heating rate of approximately 730 minutes at 10°C. As shown in the figure, an electrode 5'5' made of a coiled conductor embedded in the molded body 1 may be used.

The heat insulating material 3 is for preventing the heat generated in the molded body 1 from escaping from the back surface, and the heat insulating material 3 is made of, for example, a hard urethane material. The covering material 4 serves to protect and electrically insulate the molded body 1 and the heat insulating material 3, and is made of, for example, vinyl chloride resin or polyimide resin.

The ceramic layer 2 is for efficiently emitting far-infrared rays. Note that far-infrared rays as used in the present invention refer to infrared rays having a wavelength of approximately 4 μm or more.

The ceramic layer 2 is formed by coating with a paint mixed with ceramic powder, or by pasting a ceramic sheet. Therefore, the ceramic layer is not only a layer consisting purely of ceramic components, but also a layer containing a certain amount of resin necessary for layer formation. In this example, the ceramic layer 2 is provided on the coating material 4, but since the ceramic layer 2 normally has electrical insulation properties, the ceramic layer 2 is placed directly on the surface of the molded body 1. It may also be provided. In short, any configuration is sufficient as long as the ceramic layer 2 serves as a heat dissipation surface of the plate-shaped heating element.

The ceramic layer 2 may have a smooth surface, or
The material may have fine irregularities on its surface or may be a foam material. In the case of a coat layer, the thickness of layer 2 is, for example, 20 to 200 μm, usually 30 to 50 μm.
The thickness is in the range of about 1.5 m, but the thickness is not limited to this, and in the case of a sheet, it is thicker.

Materials with good far-infrared characteristics include ceramic materials that have characteristics close to black body radiation characteristics (100% line), as shown in curve A' in Figure 6, or ceramic materials that have characteristics close to the black body radiation characteristics (100% line), as shown in curve A' in Figure 6. In addition, there is a ceramic material that has low efficiency in a wavelength range shorter than about 4 μm, but has high efficiency in a longer wavelength range, close to the radiation characteristics of a fish body.

Any of these can be used for the ceramic layer 2 of this invention.

Note that FIG. 6 shows a case where the temperature of the ceramic layer is high salinity of about 500° C., and as the temperature of the ceramic layer becomes lower, the characteristics of the latter also become close to the former. The metal layer made of silver paste material has poor far-infrared radiation characteristics, as shown by curve C in Figure 5 and curve C' in Figure 6, and of course the radiation characteristics remain poor even at low temperatures. It is.

Materials with characteristics close to blackbody radiation include, for example, transition element oxide sintered ceramics, such as manganese dioxide (Mn
O□), iron oxide (Felon), cobalt oxide (Co
O), ceramics such as copper oxide (CuO), chromium oxide (crtox), or an appropriate mixture of materials selected from the above materials, and at least one selected from the transition metal oxides described above. Among these materials, there are composite ceramic materials in which cordierite, β-spodumene, aluminum titanate, etc. are appropriately mixed. An example of a mixture is manganese dioxide (60%), iron oxide (
20%), copper oxide (10%), cobalt oxide (10%)
Ceramic mixed and sintered, or calcined material of this composition (25%), Honbushi clay (25%), petalite (5%)
There is a ceramic (with a small coefficient of thermal expansion) that is mixed and sintered with 0%). The radiation intensity (at 100° C.) is as shown in curve A in FIG. More specifically, for example, iron oxide (20%), mica and pulp, etc. (45%)
There is a paint made of silicone resin (35%), and this paint is commercially available as B-600 (Okimoku High Efficiency Radiation Paint, Organic Solvent Based, Black). The ceramic layer 2 can be formed by applying and baking this paint. The heat dissipation surface on which the ceramic layer 2 is formed has the property of sufficiently radiating far infrared rays.

Ceramics whose efficiency improves when the wavelength exceeds about 4 μm include zirconia, titania, alumina, and silica. For example, cordierite (2Mg
0.281□0.・5SiO□), β-spondume 7 (LizO・AlzOx ・4 Sing),
Examples include aluminum titanate (AhOx・Ti0-) and silicon carbide. The radiation intensity (at 100° C.) of the alumina system is as shown at the curved line in FIG. More specifically, titanium oxide (5%), alumina zirconia (
60%) and silicone resin (35%). This paint is commercially available as W-500 (Okimoku Highly Efficient Radiation Paint, Organic Solvent-based, White). Alternatively, titanium oxide (5%), alumina zirconia (60%)
%), and some paints are made of sodium sulfate (35%). This paint is commercially available as W-600 (Okimotsu High Efficiency Radiation Paint Water-based White). Again, the ceramic layer 2 can be formed by coating such as painting or baking. The heat dissipation surface on which the ceramic layer 2 is formed has a property of sufficiently radiating far infrared rays.

The present invention is not limited to the above-mentioned embodiments. For example, a structure may be adopted in which a metal surface whose back surface is covered with an insulating resin is coated with a ceramic layer and assembled into a molded body.

The plate-shaped heating element of the present invention may be used not only for heating a house but also as a heating means for a greenhouse for plants and the like.

〔Effect of the invention〕

The plate-shaped heating element of the present invention has a ceramic layer on the heat radiation surface, and far infrared rays are efficiently radiated. Therefore, people, animals, plants, etc. can receive an effective heat supply effect accompanied by infrared radiation. Infrared radiation is a form of heat supply, and the efficient radiation of far-infrared rays does not impair the heat supply effect, so it is in fact a highly practical product with new functions. It becomes.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of an embodiment of the plate-shaped heating element according to the present invention, FIG. 2 is a perspective view of the structure around the inorganic plate-shaped molded body of the same heating element, and FIG. , Fig. 4 is a perspective view of another example of an inorganic plate-shaped molded body, and Fig. 5 shows the infrared radiation intensity and wavelength of ceramics, etc. hail relationship graph,
FIG. 6 is a graph showing the relationship between far-infrared radiation efficiency and wavelength of ceramics, etc. L... Inorganic plate-shaped molded body 2... Ceramic layer H... Plate-shaped heating element agent Patent attorney Takehiko Matsumoto Figure 3

Claims (1)

[Claims] 1. A plate-shaped heating element comprising an inorganic plate-shaped molded body in which a conductive material is dispersed, which generates heat when energized, the heat-radiating surface of the heating element having good far-infrared radiation characteristics. A plate-shaped heating element characterized by being provided with a ceramic layer for heating.