CN101265021A - Continuous Firing Furnace - Google Patents

Abstract

The invention provides a continuous firing furnace. This continuous firing furnace efficiently cools the entire outer surface of the object to be processed, such as a glass substrate, without causing local warpage or deformation on the object to be processed, and reduces the cooling time. An introduction channel (1) and an exhaust channel (2) are provided in a cooling chamber (15) of a continuous firing furnace (10). The introduction passage and the exhaust passage are opened in substantially the entire area in the furnace width direction (Y) on the upper inner wall surface (15A) of the cooling chamber. The introduction path ejects air toward the upstream side of the conveyance direction (X). The exhaust passage exhausts the air in the cooling chamber on the upstream side of the introduction passage along the conveyance direction (X). Above the object to be processed (100) conveyed on the rollers (16), a flow path of cooled external air is uniformly formed over substantially the entire area in the furnace width direction (Y). The entire upper surface of the treated object is in uniform contact with the air.

Description

Continuous Firing Furnace

technical field

The present invention relates to a continuous firing furnace for continuously performing soaking, annealing and cooling treatment on a glass substrate for a plasma display panel (PDP).

Background technique

The continuous firing furnace has a heating chamber and an annealing chamber inside the furnace, and a cooling chamber outside the furnace. From the heating chamber, through the annealing chamber to the cooling chamber, a conveying mechanism for continuously conveying the processing object is arranged. The continuous firing furnace in the prior art, for example, uses a roller hearth (roller hearth) in which a plurality of rollers are arranged at equal intervals as a conveying mechanism.

Both ends of the plurality of rollers are exposed to the outside through through holes in the side walls of the furnace and the cooling chamber, and the one end exposed to the outside is rotated by being supplied with a driving force. A glass substrate to be processed is conveyed in a state mounted on a thin-plate-shaped carrier by rotation of a plurality of rollers.

As an example, the temperature of the glass substrate is raised to 500-600°C and held for a predetermined time while being transported in the heating chamber (soaking treatment), and then cooled to about 350-450°C while being transported in the annealing chamber (annealing treatment). , while being transported in the cooling chamber, it is rapidly cooled to a temperature that can be taken out (cooling treatment) (for example, refer to Japanese Patent Laid-Open Publication No. 2003-148869). In addition, the cooling chamber has a water-cooled fin cooler and a fan filter unit (hereinafter referred to as FFU (fan filter unit)). The water-cooled finned cooler cools the processing object. The FFU ensures the cleanliness of the area through which objects are processed.

However, the water-cooled fin cooler and the FFU in the cooling chamber of the conventional continuous firing furnace are separately installed according to their respective purposes, and cannot cooperate with each other to function. In addition, the cooling chamber in the prior art does not have an exhaust mechanism, but the cooling air introduced into the cooling chamber exchanges heat with the air in the cooling chamber and the glass substrate, and then flows from the supply ports formed on the side walls of the cooling chamber. Multiple through-holes for rollers discharge to the outside. When external air is locally introduced into the cooling chamber from the FFU through a plurality of introduction channels, only a part of the glass substrate near the introduction channels may be rapidly cooled, causing local warpage or deformation.

Contents of the invention

The object of the present invention is to provide a continuous firing furnace, which is provided with an exhaust passage in the cooling chamber, and can efficiently cool the entire surface of the processing object such as a glass substrate by controlling the flow path of the cooling air introduced into the cooling chamber. There is no local warping or deformation on the object to be processed, and cooling processing can be realized in a short time.

The continuous firing furnace of the present invention has a structure in which an introduction passage and an exhaust passage are provided on the same inner wall surface in the cooling chamber into which the heated processing object is carried in a predetermined conveyance direction. The introduction path uniformly sprays cooling gas over the entire area in the direction perpendicular to the conveyance direction. The exhaust passage exhausts gas uniformly over the entire area in the direction perpendicular to the conveyance direction. The introduction channel and the exhaust channel are arranged along the conveying line.

In this structure, in the cooling chamber, the flow path of the cooling gas along the conveyance line to be processed is uniformly formed over the entire area in the furnace width direction perpendicular to the conveyance direction. The cooling gas evenly contacts the entire surface of the processing object conveyed in the cooling chamber, and uniformly cools the entire surface of the processing object.

In this configuration, the exhaust passage can be arranged on the upstream side of the introduction passage in the conveyance direction. In this way, the object to be processed can be efficiently brought into contact with the cooling gas, and the cooling efficiency can be improved.

Furthermore, the inlet channel can eject cooling gas in the direction of the exhaust channel. In this way, the flow path of the cooling gas from the introduction passage to the exhaust passage can be efficiently formed.

In addition, the introduction passage and the exhaust passage may be arranged on the upper inner wall surface of the cooling chamber. In this manner, in the roller hearth type continuous firing furnace, the object to be conveyed and processed placed on the carrier is efficiently cooled by bringing the cooling gas into contact with the upper surface.

According to the present invention, in the cooling chamber, the flow path of the cooling gas along the conveying line of the processing object can be uniformly formed over the entire area in the furnace width direction. The cooling gas can be uniformly brought into contact with the entire surface of the processing object conveyed in the cooling chamber, and the entire surface of the processing object can be uniformly cooled. Thereby, the cooling process can be realized in a short time without locally warping or deforming the object to be processed.

Description of drawings

Fig. 1 is a side sectional view showing an example of a continuous firing furnace according to an embodiment of the present invention.

Fig. 2 is a side sectional view of a cooling chamber of the above-mentioned continuous firing furnace.

In Fig. 3, (A) is a cross-sectional view at position A-A in Fig. 2, and (B) is a cross-sectional view at position B-B in Fig. 2 .

Detailed ways

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. Fig. 1 is a side sectional view showing an example of a continuous firing furnace according to an embodiment of the present invention. The continuous firing furnace 10 has a first heating chamber 12, a second heating chamber 13, and an annealing chamber 14 along the conveying direction X in the furnace 11, and the furnace 11 located on the downstream side of the annealing chamber 14 along the conveying direction X There is a cooling chamber 15 outside. In the first heating chamber 12 , the second heating chamber 13 , the annealing chamber 14 , and the cooling chamber 15 , a plurality of rotatable rollers 16 are arranged at equal intervals along the conveyance direction X.

The first heating chamber 12 performs the first temperature raising treatment and the first soaking treatment, for example, heating the treatment object to 350° C. to 400° C. and maintaining this state for 20 minutes. The second heating chamber 13 performs the second temperature raising treatment and the second soaking treatment, for example, heating the treatment object to 600° C. and maintaining this state for 30 minutes. The annealing chamber 14 performs annealing treatment, for example, cooling the object to be processed to 400° C. over 40 minutes. The cooling chamber 15 performs cooling treatment, for example, cooling the object to be treated to normal temperature in about 50 minutes.

Both end portions of the plurality of rollers 16 passing through the side walls of the furnace 11 and the cooling chamber 15 are rotatably supported from the outside. The plurality of rollers 16 are rotated by being supplied with a driving force at one end, and the processing target 100 such as a glass substrate placed on the upper surface of the carrier 200 is conveyed along the conveyance direction X.

Fig. 2 is a side sectional view of a cooling chamber of the above-mentioned continuous firing furnace. In Fig. 3, (A) is a sectional view at A-A in Fig. 2, and (B) is a sectional view at B-B in Fig. 2 . The cooling chamber 15 has an inlet channel 1 and an exhaust channel 2 . The introduction passage 1 and the exhaust passage 2 are opened, for example, on the upper inner wall surface 15A of the cooling chamber 15 .

A water-cooling jacket (not shown) is disposed on the upper wall of the cooling chamber 15 , and a plurality of water-cooling fins 15B protrude from the upper inner wall surface 15A. As an example of a water-cooling jacket, a copper pipe through which cooling water flows is used and embedded in a stainless steel (SUS) muffle furnace with heat-conducting cement in a coiled state. The water-cooling fins 15B are arranged such that their longitudinal directions are parallel to the conveyance direction X, and promote heat exchange between the air in the cooling chamber 15 and the cooling water in the water-cooling jacket.

In the example shown in FIG. 2 , there are plural pairs of introduction passages 1 and exhaust passages 2 . In each pair of the introduction path 1 and the exhaust path 2 , for example, the exhaust path 2 is arranged on the upstream side of the introduction path 1 in the conveyance direction X.

The introduction channel 1 has a filter 17 and a wind direction plate 18 . The introduction channel 1 supplies air from unillustrated high-pressure clean air, clean dry air (CDA, clean dry air), or a blower. The filter 17 removes dust in the air passing below. The wind direction plate 18 directs the ejection direction of the air from the introduction duct 1 toward the upstream side in the conveyance direction X. As shown in FIG.

The air supplied to the introduction duct 1 is ejected toward the upstream side in the conveyance direction X in the cooling chamber 15 after passing through the filter 17 to remove dust. The introduction duct 1 is opened in the cooling chamber 15 over substantially the entire area in the furnace width direction Y perpendicular to the conveyance direction X, and blows air uniformly over substantially the entire area in the furnace width direction Y.

The exhaust duct 2 has a fan 21 . The fan 21 discharges the air in the cooling chamber 15 to the outside through the exhaust passage 2 . The exhaust passage 2 is opened over substantially the entire area in the furnace width direction Y in the cooling chamber 15, and discharges the air in the cooling chamber 15 uniformly in substantially the entire area in the furnace width direction Y.

The air ejected from the introduction duct 1 flows upstream in the conveyance direction X along the upper surface of the processing object 100 . The exhaust duct 2 mainly exhausts the air above the processing object 100 to the outside.

Thus, the air ejected from the introduction duct 1 flows upstream along the upper surface of the processing object 100 in the conveyance direction X, and most of the air is discharged to the outside by the exhaust duct 2 after exchanging heat with the processing object 100 . Above the object 100 to be processed, a cooling gas flow path is uniformly formed over substantially the entire area in the furnace width direction Y from the downstream side in the conveyance direction X to the upstream side.

Water-cooling fins 15B protrude from the inner wall surface 15A of the openings of the inlet channel 1 and the exhaust channel 2 , and the flow path of the air introduced from the inlet channel 1 is parallel to the longitudinal direction of the water-cooling fins 15B. The introduced air is cooled by the water-cooling fins 15B while passing over the object to be processed 100 , and continues to exchange heat with the object to be processed 100 until it is exhausted through the exhaust duct 2 . The introduction channel 1 and the exhaust channel 2 work together with the water-cooling fins 15B to efficiently cool the processing object 100 .

In the cooling chamber 15, the entire upper surface of the processing object 100 is uniformly cooled by the cooling gas. Thereby, the processing object 100 can be cooled in a short time without warping or deforming the processing object 100 .

Since the cooling gas flows in the direction opposite to the conveyance direction of the processing object 100, heat exchange can be effectively performed between the cooling gas and the processing object 100 as a whole, and the processing object 100 can be efficiently cooled by the cooling gas. .

The present invention is also similarly applicable to a carrier-less continuous firing furnace in which the object 100 to be processed is conveyed directly by the rollers 16 without being placed on the carrier 200 .

In addition, the distance between the introduction duct 1 and the exhaust duct 2 in the conveyance direction X can be appropriately set according to the length of the processing object 100, the length of the cooling chamber 15, and the like. It is not necessarily necessary to provide multiple pairs of the introduction channel 1 and the exhaust channel 2 .

The surface on which the introduction channel 1 and the exhaust channel 2 are arranged in the cooling chamber 15 is not limited to the upper inner wall surface 15A, as long as the introduction channel 1 and the exhaust channel 2 are satisfied on the same surface, they can also be arranged on other surfaces superior. However, in consideration of the cooperation with the water-cooling fins 15B and the cooling efficiency for the processing object 100 conveyed on the rollers 16, it is most optimal to arrange the introduction channel 1 and the exhaust channel 2 on the upper inner wall surface 15A. Effective.

In addition, in the description of the above-mentioned embodiment, it should be thought that it is an illustration in all the points, and it should not restrict|limit the content. The scope of protection of the present invention is not indicated by the above-mentioned embodiments, but is based on the claims. In addition, the protection scope of the present invention should include all changes within the meaning and scope equivalent to the claims.

Claims (5)

1. continuous burning furnace, it has process object after the heating by the cooling room of sending into along regulation carrying direction, it is characterized in that,

Above-mentioned cooling room has at above-mentioned carrying direction place, same inner-wall surface upper edge circuit: spray the introduction channel of cooling gas equably in whole zone with the vertical direction of above-mentioned carrying direction, and with the gas in the above-mentioned cooling room in the exhaust-duct of discharging equably with the whole zone of the vertical direction of above-mentioned carrying direction.

2. continuous burning furnace as claimed in claim 1, wherein,

Above-mentioned exhaust-duct is disposed at the upstream side along above-mentioned carrying direction of above-mentioned introduction channel.

3. continuous burning furnace as claimed in claim 2, wherein,

Above-mentioned introduction channel direction towards above-mentioned exhaust-duct in above-mentioned cooling room sprays cooling gas.

4. continuous burning furnace as claimed in claim 1, wherein,

Above-mentioned introduction channel direction towards above-mentioned exhaust-duct in above-mentioned cooling room sprays cooling gas.

5. as any described continuous burning furnace of claim 1 to 4, wherein,

Above-mentioned introduction channel and above-mentioned exhaust-duct are positioned at the inner-wall surface of the upside of above-mentioned cooling room.

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