JPH0362489A - Far infrared heating device - Google Patents

Abstract

PURPOSE:To shorten temperature increasing time by constituting a far infrared generating source and a hot air generating source by a porous ceramic sintered body. CONSTITUTION:A far infrared generating source 1 is formed of porous silicon carbide sintered body as a porous ceramic sintered body formed into a plate, and terminal parts 1A, 1A formed on its both ends are held by a casing through holders 2, 2, having electric insulating function and heat insulating function. Each of the terminal parts 1A, 1A is electrically connected to a power source input terminal (not shown), whereby the far infrared generating source 1 is installed to an electrifying circuit (not shown). The casing 3 has its flat surface largely opened, and a reflector 4 for reflecting far infrared rays frontward is disposed between the back surface of the far infrared generating source 1 and the casing 3. An air hole 3A is formed in the rear center of the casing 3. By operating a blower 5, air is sent from the air hole 3A into the casing 3 as shown by an arrow X1 to blow hot air toward the front of the far infrared generating source 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a far-infrared heating device used for heating, drying, etc., for example.

[Prior Art] It has been well known that far-infrared heating devices are used for heating, drying, etc.
For example, as shown in Figure 3, a metal wire (chromium wire) B is built into a tubular ceramic A, and the tubular ceramic A is heated by heating the metal wire B, and far infrared rays are emitted from its surface. As shown in Figure 4, there are known devices in which a solid or hollow rod-shaped (or plate-shaped) ceramic A is directly energized to generate heat and emit far-infrared rays. [Problems to be Solved by the Invention] However, the far-infrared ray generation source shown in FIG. It takes a relatively long time to heat up the tubular ceramic A to the temperature range (400 to 600°C) where the most far infrared rays are emitted from the start of energization, and the initial rise temperature characteristics are poor. The metal wire B does not have a function as a far-infrared ray generation source, but merely heats the tubular ceramic A, and the thermal energy required to heat the tubular ceramic A is equal to that of the metal wire B. It is only a small part of the heat generated energy, and there is a lot of energy loss, and most of it is used to heat nearby members and air, so the effective utilization rate of thermal energy is low.

Furthermore, the tubular ceramic A used as a far-infrared radiation source has a low porosity (approximately 1% or less) and a very small specific surface area, so it has a low emissivity of far-infrared rays, that is, it has no heating or drying effect. It has problems such as small size.

On the other hand, the far-infrared ray generation source shown in Fig. 4 uses a direct heating method that heats the ceramic A by directly applying electricity to the ceramic A, so the time required to raise the temperature to the temperature range where the most far-infrared rays are emitted can be shortened. Although Ceramic A has the advantages of improved initial rise temperature characteristics and low energy loss, it has a low porosity, similar to the tubular Ceramic A described in FIG.
Since the specific surface area is small, it has problems such as low radiation efficiency of far infrared rays and low heating or drying effect.

On the other hand, a method has been proposed in which the above-mentioned tubular ceramic A or ceramic A is blown to force the heated air near the far-infrared generation source to be blown out as hot air to improve the heating and drying effects. There is.

However, since both the tubular ceramic A and the ceramic A shown in FIG. 4 have low porosity and no air permeability, the above-mentioned air is blown only onto the surfaces of both ceramics A.

Therefore, a problem arises in that the surface temperature of both ceramics A is unnecessarily lowered and the far-infrared emissivity with respect to the supplied power is reduced.

The present invention was developed in view of the above circumstances, and is a far-field technology that improves the initial rise temperature characteristics, suppresses energy loss, and increases the radiation efficiency of far-infrared rays, thereby improving the heating or drying effect. The purpose is to provide an infrared heating device.

[Means for Solving the Problems] In order to achieve the above object, the present invention equips an energizing circuit with a porous ceramic sintered body as a source of far infrared rays and a source of hot air (secondary radiation heat). In particular, the porous ceramic sintered body is preferably a porous silicon carbide sintered body.

[Function] According to the present invention, far infrared rays can be emitted by directly applying electricity to the porous ceramic sintered body.

Furthermore, since porous ceramics with high porosity and a large specific surface area are used as the far-infrared radiation source, the radiation efficiency of far-infrared rays is high.

Furthermore, in order to forcibly blow out the heated air near the far-infrared ray generation source as a hot air generation source, when air is started, the interior of the porous far-infrared ray generation source is also ventilated. Therefore, the surface temperature of the far-infrared ray generation source does not decrease, and since the temperature of the ventilation is raised by the heat exchange effect performed during the internal ventilation process, high-temperature hot air can be emitted. Furthermore, organic matter such as dust contained in the airflow is burned during the ventilation process, making it possible to emit clean hot air.

【Example] Hereinafter, embodiments of the present invention will be described based on the drawings.

FIG. 1 is a schematic longitudinal sectional side view showing an embodiment of the present invention. Terminal portions IA, IA formed at both ends are held in the casing 3 via a holder 2.2 having electrical insulation and heat insulation functions. Each of the terminal parts IA and IA is electrically connected to a power input terminal (not shown), so that
The configuration is such that a far-infrared ray generating source 1 is installed in a current-carrying circuit (not shown).

The casing 3 has its front side wide open to expose the heat generating part of the far infrared ray generation source 1.
A reflector plate 4 that reflects far infrared rays forward is arranged between the back surface of the casing 3 and the casing 3. In addition, a vent hole 3A is formed at the rear center of the casing 3, and by operating the blower 5, an arrow Xi is drawn from the vent hole 3A into the casing 3.
The physical properties of the porous silicon carbide sintered body constituting the far-infrared ray generating source 1 are shown in the column of Table 1 below.

Table 1 In the above configuration, far infrared rays can be emitted as shown by arrow x2 by direct energization to the porous silicon carbide sintered body constituting far infrared ray generation source l, so that far infrared rays can be emitted from the start of energization. Time to heat far infrared rays source 1 to the temperature range where it emits the most far infrared rays! It is possible to reduce the size. Therefore, initial rise temperature characteristics are improved, and energy loss is suppressed compared to conventional indirect heating methods, so it is possible to improve thermal efficiency.

As is clear from column 1 of Table 1 above, the porous silicon carbide sintered body has a high porosity and a large specific surface area.
The radiation efficiency of far infrared rays indicated by 2 is extremely high, so the heating or drying effect is greatly improved.

Further, the heated air near the far-infrared ray source 1 is blown out as hot air in front of the far-infrared ray source 1 by the operation of the blower 5, as shown by the arrow xl, but in this case, from the vent 3A. The blown air flows along the surface of the far-infrared radiation source 1 and passes through the inside of the porous far-infrared radiation source 1. Therefore, only the surface temperature of the far-infrared radiation source 1 is not reduced.

Moreover, since heat exchange occurs during the process of passing through the far-infrared ray generation source 1, high-temperature hot air can be emitted to increase the heating or drying effect. Furthermore, as the air passes through the inside of the far-infrared ray source 1, organic matter such as dust contained in the air is burned, so no clogging occurs, and
It has a purifying effect by emitting clean hot air and can purify the room.

In addition, in the above embodiment, the far-infrared ray generation source l is constructed from a porous silicon carbide sintered body formed into a plate shape, but
As shown in FIG. 2, the far-infrared ray generating source l may be constructed of a tubular porous silicon carbide sintered body. In this FIG. 2, the same or corresponding parts as in FIG. , so a detailed explanation will be omitted.

Further, as a comparative example that the present inventor has diligently studied, even if the far-infrared ray source 1 is constructed of porous recrystallized ceramics having the physical characteristics shown in column II of Table 1,
Although heating is possible, the porosity is small and insufficient at about 23%, and the specific surface area is also small, so the radiation efficiency of far infrared rays is also small compared to the present invention.

[Effects of the Invention] As explained above, according to the present invention, since the far-infrared ray generation source and the hot air generation source are configured with the porous ceramic sintered body, far-infrared rays can be radiated by direct energization. . Therefore, it is possible to shorten the time required to heat up the far-infrared source to the temperature range where the most far-infrared rays are emitted from the start of energization, and the initial rise temperature characteristics are improved. In comparison, energy loss is suppressed, so thermal efficiency can be improved.

Furthermore, since the porous silicon carbide sintered body with high porosity and large specific surface area is used as the far-infrared radiation source, the radiation efficiency of far-infrared rays is extremely high. Therefore, the heating or drying effect is greatly improved.

Furthermore, when air is blown to forcibly blow out the heated air near the far-infrared generation source as hot air, the inside of the porous far-infrared generation source is also ventilated, so it functions as a hot air generation source. Without lowering only the surface temperature of the far-infrared ray source, the heat exchange effect performed during the ventilation process can emit high-temperature hot air to improve heating and drying effects. It can also be used to purify organic matter, such as dust, by burning it to release clean air.

[Brief explanation of drawings]

1 and 2 show an embodiment of the present invention, FIG. 1 is a schematic longitudinal sectional side view of the first embodiment, FIG. 2 is a partial sectional view of another embodiment, and FIG. 3 is a conventional example. A schematic explanatory diagram, FIG. 4 is a schematic explanatory diagram of another conventional example. l... far infrared radiation source

Claims (2)

[Claims] (1) A far-infrared heating device characterized in that a energizing circuit is equipped with a porous ceramic sintered body as a far-infrared ray and hot air generation source. (2) The far-infrared heating device according to claim (1), wherein the porous ceramic sintered body is a porous silicon carbide sintered body.