JP2003279253A - High-temperature burning furnace - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure enabling prevention of distortion due to thermal expansion of an inner wall of the furnace and also effective prevention of furnace contamination due to generation of dust from oxidation of a component and a heater in a high-temperature burning furnace having air-right structure requiring high cleanliness. <P>SOLUTION: In this high-temperature burning furnace 1, a plurality of heat insulation boards 5 formed by covering the surface of a plate-like heat insulating material 7 with a stainless sheet 9 are used and combined like a box without bonding to construct a structure 11, the structure 11 is installed in the furnace to burn material to be burnt in the interior of the structure 11. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-temperature firing furnace used for firing glass parts, semiconductors, and the like that do not like contamination, and which requires high cleanliness.

[0002]

2. Description of the Related Art Conventionally, for products such as glass parts and semiconductors that do not like contamination, which require a high degree of cleanliness during firing, use an airtight firing furnace in which the entire inner wall is made of stainless steel such as SUS. The firing was done.

[0003]

However, in a high-temperature firing furnace in which the temperature inside the furnace exceeds 700 ° C., the inner wall made of stainless steel is likely to be distorted due to thermal expansion, etc. There was a problem that it was easily damaged. Further, there is a problem that the cleanliness inside the furnace is adversely affected by the oxidation of stainless steel.

In addition, in order to maintain the cleanliness inside the furnace, in addition to preventing dust and the like from entering from the outside of the furnace, dust generated from a heater used for heating an object to be burned (metal heating element It is an important issue to prevent in-furnace contamination due to scale peeling caused by oxidation.

The present invention has been made in view of such circumstances, and an object of the present invention is, in a high-temperature firing furnace having an airtight structure that requires high cleanliness, due to thermal expansion of an inner wall of the furnace. It is an object of the present invention to provide a structure capable of preventing distortion and effectively preventing in-furnace contamination due to oxidation of constituent materials and dust generation from a heater.

[0006]

According to the present invention, a structure in which a plurality of heat insulating boards each having a plate-shaped heat insulating material whose surface is covered with a stainless steel plate are used, and which are combined in a box shape without being connected to each other Is provided in a furnace so that a material to be fired is fired inside the structure, and a high-temperature firing furnace is provided.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION FIG. 1 is an explanatory view showing an example of an embodiment of a high temperature firing furnace according to the present invention. As described above, in the high temperature firing furnace 1 of the present invention, the plate-shaped heat insulating material 7 is used.
A plurality of heat insulating boards 5 each having a surface covered with a stainless plate 9 are used, and a structure 11 in which the heat insulating boards 5 are combined in a box shape without being connected to each other is installed in the furnace. The structure 11 is contained in the inner wall 3 and the outer wall 2 of the furnace and the water cooling jacket 4 in the gap between them.

Then, since the object to be fired 13 is fired inside the structure 11 composed of the heat insulating board 5, the heat during firing is appropriately shielded by the structure 11. Therefore, even if the inner wall 3 of the furnace is entirely made of stainless steel such as SUS, it is prevented from being exposed to a high temperature and being distorted or oxidized by thermal expansion or the like.

It should be noted that the structure 11 itself is a combination of a plurality of heat insulation boards 5 in a box shape, and is not such that they are mutually coupled and integrated.
Even if each of the heat insulating boards 5 constituting the No. 1 is exposed to a high temperature and thermally expanded, the positional relationship between the heat insulating boards 5 is slightly displaced from each other, and the entire structure 11 is not greatly distorted and damaged. .

Further, the heat insulating board 5 is a plate-shaped heat insulating material 7.
Since the surface of the heat insulating board 5 is covered with the stainless plate 9, even if friction occurs due to thermal expansion or the like on the contact surfaces of the heat insulating boards 5 when the structure 11 is formed, friction powder is less likely to be generated, and clean The environment inside the furnace can be maintained. As a specific material for the heat insulating material 7, a fiber board formed of an inorganic binder or the like is preferable.

In the present invention, the heat insulating board 5
Is important. For example, if the thickness of the heat insulating board 5 is increased, the heat shielding property is improved, but the portion of the stainless plate 9 facing the inside of the structure 11 is heated to the same internal temperature. In this case, even if the structure 11 is composed of a plurality of divided heat insulation boards 5, it is difficult to completely avoid the influence of thermal expansion, and it is difficult to maintain the in-furnace cleanliness by oxidation due to heating. Become.

On the other hand, if the thickness of the heat insulating board 5 is reduced, the problems of thermal expansion and oxidation described above are eliminated, but the heat shielding effect is reduced, so that the heat in the furnace escapes to the water cooling jacket 4 through the inner wall 3. Therefore, an excessive amount of heat generation is required to maintain the temperature in the furnace, and a heating source with a large amount of heat generation corresponding to that is required. The optimum thickness of the heat insulating board 5 depends on the temperature inside the furnace, but when the temperature inside the furnace is 700 ° C., for example, it is desirable to set the thickness to about 20 mm.

As shown in FIG. 1, the high-temperature firing furnace of the present invention uses, as a heating means, a metal heating element 15 and Si that emits far infrared rays to the object to be fired by receiving heat generated from the metal heating element 15. It is preferable to use a heater having a muffle plate 17 made of impregnated SiC and having a structure in which the metal heating element 15 is isolated from the surrounding atmosphere by the muffle plate 17 and a cover 19 made of quartz or the like.

Here, Si-impregnated SiC is a refractory material obtained by impregnating SiC with metallic Si, and is known to have a high far-infrared emissivity. Therefore, the metal heating element 1
When the muffle plate 17 made of Si-impregnated SiC receives the heat emitted from the No. 5, and the far infrared rays are radiated from the muffle plate 17 to the object to be fired 13, the object to be fired 13
Can be heated quickly.

Muffle plate 17 made of Si-impregnated SiC
Is manufactured by, for example, molding SiC powder into a predetermined muffle plate shape, and firing the obtained molded body while impregnating the metal Si in a reduced pressure inert gas atmosphere or vacuum in which the metal Si is present. be able to. The metal Si that is melted during firing and impregnated into the molded body binds the SiC particles, which are filled in the pores and become the aggregate, and densify the molded body.

The metal heating element 15, which is a heating source, is isolated from the surrounding atmosphere by such a muffle plate 17 and the cover 19. As a result, it is possible to effectively prevent the inside of the furnace from being contaminated by dust generated from the metal heating element 15.
As the metal heating element 15, specifically, an iron-chromium-aluminum metal wire or the like molded with ceramics can be preferably used.

[0017]

As described above, according to the present invention, it is possible to prevent distortion and oxidation due to thermal expansion of the inner wall of the furnace in the high-temperature firing furnace having an airtight structure that requires high cleanliness. Further, it is possible to effectively prevent the inside of the furnace from being contaminated due to dust generated from the heater.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an example of an embodiment of a high temperature firing furnace according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... High temperature firing furnace, 2 ... Outer wall, 3 ... Inner wall, 4 ... Water cooling jacket, 5 ... Insulation board, 7 ... Insulation material, 9 ... Stainless plate, 11 ... Structure, 13 ... Firing object, 15 ... Metal heating element , 17 ... Muffle plate, 19 ... Quartz cover.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masaya Onishi             2-56 Suda-cho, Mizuho-ku, Nagoya-shi, Aichi             Nusy Kei Kirntech Co., Ltd. F-term (reference) 4K051 AA09 AB01 AB03 AB05 FA07                 4K061 AA03 BA09 BA11 CA08 CA11                       CA20

Claims (2)

[Claims] 1. A structure in which a plurality of heat insulating boards each having a plate-shaped heat insulating material whose surface is covered with a stainless steel plate are used, and which are combined in a box shape without being bonded to each other, is installed in a furnace, and the structure is formed. A high-temperature firing furnace characterized in that a material to be fired is fired inside the body. 2. A metal heating element, and a muffle plate made of Si-impregnated SiC that radiates far infrared rays to an object to be fired by receiving heat generated from the metal heating element, the metal heating element being the muffle plate. The high-temperature firing furnace according to claim 1, further comprising a heater having a structure that is isolated from an ambient atmosphere by a cover and a cover.