JP2001012706A - Infrared ray generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an infrared ray generator for effectively radiating infrared rays. SOLUTION: A catalyst layer 20 for catalytic combusting a vaporized liquid fuel 71 is employed as an infrared ray generator, and the surface of the catalyst layer 20 is exposed to the outside as an infrared ray generation surface 21. Since combustion is effected in the catalyst layer 20 of the infrared ray generation source, the generation source can be effectively heated, and further since the catalytic combustion is achieved without any flame, heating efficiency is also high. The outside can be directly irradiated with infrared rays from the catalyst layer 20. Thus, there can be realized an infrared ray generation apparatus 5 having higher infrared ray generation efficiency of infrared rays.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an infrared ray generator for emitting infrared rays to an object.

[0002]

2. Description of the Related Art As an infrared ray generating device that emits infrared rays to an object such as a person or a wall, a device that burns liquid fuel by flame and generates infrared rays is known. For example,
No. 4,178,781 discloses, as an infrared ray generator using infrared rays as a heat source, a combustion chamber made of a refractory material, a nozzle (nozzle device) for flame burning liquid fuel attached to a side end inside the combustion chamber. An apparatus is disclosed that includes a perforated metal plate disposed across an outer end of the combustion chamber to substantially close the combustion chamber. In this device, the perforated metal plate becomes incandescent by the flame combustion in the combustion chamber, and the heat on its surface is radiated to the outside.

[0003]

In this infrared ray generating apparatus, fuel such as kerosene is primarily burned in a combustion chamber, and the perforated metal plate is heated by the heat, and infrared rays emitted from the heated metal plate are used. are doing. That is, when the fuel is sprayed from the nozzle, flame combustion is started immediately thereafter, and the entire combustion chamber is heated. Then, only infrared rays emitted from the heat radiation surface which is a part of the heated combustion chamber are used. Therefore, only a part of the energy generated by the flame combustion is emitted forward as infrared rays from the heat radiation surface, and it cannot be said that the energy generated by the combustion is utilized sufficiently effectively.

[0004] Therefore, an object of the present invention is to provide an infrared ray generating device that can more effectively utilize the energy generated by combustion and generate infrared rays more efficiently. And, when used as a heating appliance, an object is to provide an infrared ray generating device that is efficient and has a high heating capacity.

[0005]

As described above, when burning in a substantially closed combustion chamber provided with a heat radiating surface, only infrared rays provided to the outside through the heat radiating surface can be used. It is also possible to burn in an open combustion chamber without a heat-dissipating surface or the like. In this case, energy such as heat or light generated from the flame can be released to the outside world. However, it is dangerous if the flame goes out directly. In addition, since the conditions in the combustion chamber are not stable, stable combustion cannot be continued efficiently. Furthermore, since energy is radiated from the flame to the outside world, there are many components other than infrared rays such as visible light, and the radiation efficiency of infrared rays is not so high.

Therefore, the inventors of the present application focused on catalytic combustion, which is flameless combustion, and arranged a catalytic layer for performing catalytic combustion on the surface, thereby making the catalytic layer an infrared ray generating source and generating the infrared ray. Infrared rays are emitted directly from the source to the outside. That is, the infrared ray generating device of the present invention has a catalyst layer capable of catalytically burning the vaporized liquid fuel,
It is characterized in that its front surface is exposed to the outside so as to serve as an infrared emitting surface for emitting infrared light. Further, behind the catalyst layer, a vaporization chamber capable of vaporizing the liquid fuel by the radiant heat of the catalyst layer is provided, and the liquid fuel is vaporized by the radiant heat of the catalyst layer, and the vaporized liquid fuel is primarily burned in the catalyst layer. Like that.

[0007] Catalytic combustion is a catalytic reaction which is flameless and oxidizes within the catalyst layer, ie, combustion proceeds. Therefore, even if the catalyst layer is disposed on the surface, there is little danger, and the combustion reaction can be stably performed. Furthermore, since it is flameless combustion, most of the energy generated by the combustion is consumed for heating the catalyst layer, and is emitted as infrared rays from the catalyst layer which has become hot. Therefore, the ratio of energy generated by combustion is released as energy in a form other than infrared light such as visible light,
Infrared ray generation efficiency increases.

Further, in the infrared ray generating apparatus of the present invention, only the catalyst layer which is a source of infrared rays is directly heated by catalytic combustion, and the infrared rays emitted from the catalyst layer are used. Therefore, a large proportion of the energy generated by combustion can be emitted as infrared rays. In addition, since the catalyst layer is exposed on the surface, infrared rays generated from the catalyst layer are directly emitted to the outside. Therefore, the generation efficiency of infrared rays that can be used in the outside world is high, and when used as a heating device, effective heating can be performed.

[0009] Further, in the infrared ray generating apparatus by catalytic combustion, the emission of harmful or odor-causing components in the combustion exhaust gas such as nitrogen oxide or carbon monoxide can be reduced, and the noise can be reduced. Therefore, it is suitable for an infrared ray generating device used as a heating device or the like. Further, since the lean air-fuel mixture can be burned and the range of adjusting the amount of combustion is wide, there are many advantages such as easy control of the amount of infrared rays generated.

In order to maintain a good catalytic combustion state,
It is desirable to make the frequency of contact between the catalyst and the fuel sufficiently high. On the other hand, if the heat radiation from the catalyst layer decreases and the temperature itself of the catalyst layer increases, this causes a flashback phenomenon. Therefore, the opening ratio of the catalyst layer is about 50 to 70%, and the thickness is 5%.
About 20 mm is desirable.

It is desirable that the liquid fuel supplied to the catalyst layer is sufficiently vaporized. To promote the vaporization, a porous radiant plate heated by the radiant heat of the catalyst layer is provided in the vaporization chamber. It is desirable to provide it facing the catalyst layer.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an outline of a heating device according to the present invention. In this example, an infrared generator according to the present invention is used as a heating device 1.

In the heating apparatus 1 of this embodiment, an infrared ray generating device 5 is mounted on an upper portion of a frame 60 with movable casters, and a fuel tank 2 is mounted on a lower portion, and these can be moved integrally. Therefore, it is possible to freely move to an appropriate place and to emit infrared rays by operating the infrared ray generating device 5 at that place. By changing the direction of the frame 60, the irradiation direction of the infrared rays can be adjusted.

The infrared generator 5 of this embodiment has a substantially rectangular housing 10 which is slightly long in the horizontal direction. The housing 10 is mounted on the arm 62 so as to be able to pivot vertically and is supported by the frame 60. The front 10a of the housing 10 is the infrared radiation surface 21 for outputting the infrared light 73, and a guard 69 is attached to the front for safety. Therefore, the housing 1
By turning around 0, the direction of generation and irradiation of infrared rays can be changed.

FIG. 2 shows a schematic configuration of the infrared ray generating device 5 of the present embodiment. In the infrared ray generating device 5 of this example,
A catalyst layer 20 is provided facing the outside, and a surface 21 outside the catalyst layer 20 is an infrared radiation surface. As the catalyst layer 20, a catalyst such as platinum is used as a carrier (for example, lime aluminate-
What is carried on ceramics such as fused silica-titanium oxide) can be used. Ceramics have high strength at high temperatures and are easily formed into a porous structure, so that the contact area between the catalyst and the fuel can be increased. Furthermore, the radiation efficiency of infrared rays, particularly far infrared rays, is high. Therefore, it is a suitable material both as a catalyst layer for performing catalytic combustion and as a source of infrared rays. The catalyst layer 20 of the present example has a honeycomb shape. As described above, in order to efficiently and stably perform catalytic combustion and to prevent a flashback phenomenon, the opening ratio is 50 to 70% and the thickness is 50 to 70%. Those having a length d of 5 to 20 mm are suitable.

Behind the catalyst layer 20, a vaporization chamber 12 for heating and vaporizing the liquid fuel 70 by the radiant heat 74 of the catalyst layer 20.
Is provided. The vaporization chamber 12 is a hollow space provided with a heat-resistant outer shell 11 such as SUS430 or aluminum-containing ferrite. Behind the vaporization chamber 2, from the fuel tank 2 to the fuel pipe 8 and a fuel pump (not shown)
Spraying unit 1 for spraying liquid fuel 70 supplied by fuel
3. A blower 15 for sending combustion air to the vaporization chamber 12 is provided. When the fuel spray unit 13 preheats the vaporization chamber 12 and the catalyst layer 20 (preliminary combustion), the burner 1
It functions as 3 so that the sprayed liquid fuel can be ignited by an igniter (not shown).

In the infrared generator 5 of this embodiment, a porous radiating plate 30 is disposed in the vaporization chamber 12 so as to face the rear surface 22 of the catalyst layer 20 and to face the catalyst layer 20 substantially in parallel. . This porous radiation plate 30 has a porous shape,
For example, a ceramic formed in a honeycomb shape or the like, or a material obtained by spraying ceramic on a punching metal can be used. Radiant plate 30 is arranged to directly receive radiant heat 74 of catalyst layer 20, and the temperature is raised or maintained by catalytic combustion. For this reason, when the fuel sent through the vaporization chamber 12, in particular, the fuel that has not been vaporized and is not sufficiently gasified comes into contact with the radiation plate 30, the vaporization is promoted by the heat of the radiation plate 30. In addition, the radiation plate 30 is considered to have an effect of promoting the mixing of the vaporized fuel and the combustion air and also heating the combustion air. It is an important component for maintaining stable catalytic combustion.

The infrared ray generator 5 of this embodiment is controlled as follows. To perform catalytic combustion in the catalyst layer, it is necessary to set the temperature to an activation temperature of about 300 to 400 ° C. Further, since it is necessary to supply vaporized fuel to the catalyst layer, it is necessary to heat the vaporization chamber 12 to a temperature at which it vaporizes. Therefore, prior to catalytic combustion, the fuel spray unit 1
3 is used as a burner to perform pre-combustion.
The radiation plate 30 and the catalyst layer 20 are heated (preheated). In the infrared ray generating apparatus 5 of this example, a flame is formed in the vaporization chamber 12 by the preliminary combustion. However, by providing an electric heater to generate warm air, the vaporization chamber, the radiation plate, and the catalyst layer are appropriately formed. It may be preheated to the temperature.

When the temperature of the vaporization chamber 12 increases due to the preliminary combustion, the supply of fuel is stopped once to stop the combustion. Thereafter, the fuel is supplied again to the fuel spray unit 13 and the mist-like liquid fuel is jetted into the heated vaporization chamber 12. Thus, catalytic combustion starts.

Since the vaporization chamber 12 is preheated and the temperature is maintained by the radiant heat from the rear surface 22 of the catalyst layer 20 when the catalytic combustion starts, the liquid fuel 70 sprayed into the vaporization chamber 12 is gradually vaporized. . Further, the air is mixed with the combustion air supplied from the blower 15 in the vaporization chamber 12. Further, in this example, since the radiation plate 30 is provided in the vaporization chamber 12, vaporization and mixing are promoted as described above, the gasified fuel and air are mixed, and the temperature of the combustion gas 71 is increased.
Is supplied to the catalyst layer 20. And this mixed gas 71
Is oxidized (catalytic combustion) by the action of the catalyst of the catalyst layer 20.

Therefore, the infrared ray generating device 5 of the present embodiment
It can be regarded as a catalytic combustion device, and when catalytic combustion starts, primary combustion is performed in the catalyst layer 20 at the outlet of the vaporization chamber. Then, the heat generated by the catalytic combustion (primary combustion) heats the catalyst layer 20, that is, the ceramic, which is mainly a carrier, and the catalyst layer 20, which has a high temperature, is irradiated with infrared rays. In the infrared generator 5 of this example, since one surface 21 of the catalyst layer 20 is outside, the surface 73 (infrared radiation surface) is irradiated with infrared rays 73 directly from the outside.
The rear surface 22 of the catalyst layer 20 is also irradiated with infrared rays 74, whereby the radiation plate 30 and the vaporization chamber 12 are heated and used as energy for vaporizing the liquid fuel.

In order to stably maintain catalytic combustion, it is desirable to satisfy some conditions as described above. First, if the opening ratio of the catalyst layer 20 is too large, the geometric surface area of the catalyst becomes small, so that the catalytic combustion characteristics are deteriorated, and further, there is a problem in strength. On the other hand, if the aperture ratio is too small, the pressure loss increases and the combustion efficiency decreases.
Further, the passing speed of the vaporized fuel or the like supplied to the catalyst layer 20 becomes slow, so that the temperature of the infrared radiation surface 21 decreases.

When the thickness d of the catalyst layer 20 is reduced, the contact area of the vaporized fuel is reduced, so that the catalytic combustion efficiency is low and a desired amount of heat cannot be obtained. On the other hand, when the thickness d is increased, the catalytic combustion characteristics are improved, but the catalyst layer 20 may be overheated (overheated) and a flashback phenomenon may occur.

Therefore, in the catalyst layer 20 of the present embodiment, as described above, the aperture ratio is about 50 to 70%, and the thickness d is 5 to 70%.
By setting the thickness to about 20 mm, efficient catalytic combustion is stably performed, and combustion with a high calorific value and a low emission rate of harmful components is realized. At the same time, it is possible to avoid troubles such as flashback.

In order to stably maintain catalytic combustion, it is desirable to satisfy some combustion conditions in addition to these conditions. For example, if there is insufficient air in the catalyst layer, the catalytic reaction will stop and uneven combustion will occur. Therefore, it is desirable that the excess air ratio λ be 1.2 or more. On the other hand, if the excess air ratio λ is 2.0 or more, flashback may occur depending on the temperature (gas temperature) of the vaporization chamber 12. Therefore, the excess air ratio λ is 1.2 to 2.0.
It is desirable to be within the range. For this purpose, the vaporization chamber 1
Blower 15 so that the internal pressure of space 2 becomes 2-3 mmAq.
It is desirable to adjust the output of

As described above, in the infrared ray generating apparatus 5 of this embodiment, in order to generate the infrared ray 73, the fuel is flamelessly burned by the catalyst layer itself, which is a source of the infrared ray. In a conventional flame combustion type infrared ray generating device, the source of infrared rays is indirectly heated by the radiant heat of the flame, or
While it is only part of the area heated by the flame,
In the infrared ray generating apparatus of the present invention, since the infrared ray generating source is a burning body, it is directly heated, and most of the energy generated by combustion is provided to the infrared ray generating source. In addition, in the flame combustion, the generated energy is also converted into visible light and radiated, whereas the catalytic combustion is flameless combustion, so that such radiated energy is small. Therefore, the energy generated by the combustion is very efficiently supplied to the catalyst layer, which is the source of infrared rays, and the infrared rays are efficiently emitted. Then, since the catalyst layer, which is an infrared source, appears on the surface, the infrared source irradiates infrared rays directly to the outside. Also in this respect, an infrared ray generating device having high infrared irradiation efficiency can be realized. Therefore, it is possible to provide a compact and high-output infrared ray generating device.

Further, by using a ceramic or the like for the carrier of the catalyst layer 20, the emissivity in the far infrared region, which is considered to have a high heat-retaining effect, is high among infrared rays, and the infrared ray is used as a heating device or for treatment. Excellent as a generator.

Further, since the catalytic combustion is employed, an effect accompanying the catalytic combustion can be obtained. For example, it is possible to provide a highly safe infrared ray generating device 5 or a heating device 1 using the same, which lowers the combustion temperature as compared with flame combustion. Further, in the infrared generation device 5 using catalytic combustion of the present embodiment, NO
The emission of harmful combustion exhaust gas such as x can be reduced, and a lean air-fuel mixture can be burned.
Also, noise can be reduced.

In the above description, an example is shown in which the infrared ray generating device 5 is used as the heating device 1. However, the present invention is not limited to this.
Of course, it can be used for medical equipment utilizing infrared rays. Further, the catalyst layer 20 is not limited to the honeycomb shape, and may be of a sponge shape or the like.

[0030]

As described above, the infrared ray generating apparatus of the present invention employs a catalyst layer that performs catalytic combustion as an infrared ray generating source, performs primary combustion on the catalyst layer, and makes the surface of the catalyst layer infrared rays. It is made to appear outside as a generation surface. Therefore, the infrared radiation source is directly heated, and since it is flameless combustion, the heating efficiency is good. Therefore, it is possible to provide an infrared ray generating device having a high generation efficiency of infrared rays emitted to the outside. In addition, since it is flameless combustion, it is safe to expose the burning part to the surface.

Therefore, it is possible to realize a compact, high-output, and highly safe infrared ray generating apparatus. For this reason,
When the infrared ray generating device of the present invention is used as a heating device, a compact heating device with high heating efficiency can be provided. In particular, since the infrared radiation source is a catalyst layer made of ceramic, it is possible to provide a heating device that has high generation efficiency of far infrared radiation and can perform effective heating.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing a heating device equipped with an infrared ray generating device according to the present invention.

FIG. 2 is a longitudinal sectional view showing a configuration of the infrared ray generating device shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heating apparatus 2 Fuel tank 5 Infrared ray generator 10 Housing 10a Housing front 11 Outer shell of vaporization chamber 12 Vaporization chamber 13 Fuel spraying part 15 Blower 20 Catalyst layer 21 Infrared radiation surface 30 Radiation plate 60 Frame 62 Arm 69 Guard 70 Liquid fuel ( Kerosene) 71 Gas mixture 73 Infrared rays radiated to the outside 74 Radiant heat

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shoichi Muraoka 246 Sachitaka, Oaza, Suzaka City, Nagano Prefecture Inside Orion Machinery Co., Ltd. F term (reference) 3K052 AA04 AB01 AB06 AB10 AC01 FA01 FA05 3K065 TA12 TA14 TB01 TB17 TC05 TD02 TD04 TK02 TK04 TK06

Claims (3)

[Claims] 1. A catalyst layer capable of catalytically burning a vaporized liquid fuel, the front surface of which is exposed to serve as an infrared radiation surface for radiating infrared rays, and further behind the catalyst layer, An infrared ray generator having a vaporization chamber for vaporizing a liquid fuel by radiant heat of a catalyst layer, wherein the liquid fuel vaporized in the vaporization chamber is primarily burned in the catalyst layer. 2. The infrared ray generator according to claim 1, wherein an aperture ratio of the catalyst layer is about 50 to 70%, and a thickness is about 5 to 20 mm. 3. The infrared ray generator according to claim 1, wherein a porous radiant plate heated by radiant heat of the catalyst layer is disposed in the vaporization chamber so as to face the catalyst layer.