JPS61282791A - Seal structure of batch type atmosphere baking furnace - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a sealing structure for a batch atmosphere firing furnace that seals between a furnace body and a closing member that closes an opening thereof.

(Prior Art) Generally, in a batch type atmosphere firing furnace, a predetermined gas is introduced into the furnace body, and the object to be fired is fired in this gas atmosphere.

Conventionally, this type of batch-type atmosphere firing furnace has been divided into two types, depending on the type of workpieces to be fired being taken in and out of the furnace body: one is a door opening/closing type as shown in Figure 2, and the other is a type with a door that opens and closes as shown in Figure 3. There is also a formula.

The batch-type atmosphere firing furnace with an opening/closing door shown in FIG.
It has an opening 2b through which it enters and exits the furnace body 2.
A door 4 is provided to close the furnace body 2. The door 4 has a fixing hole 4a, into which a bolt 5 protruding from the side surface 2a of the furnace body 2 is inserted, and the layer 4 is fixed to the furnace body 2 with a nut 6.

On the other hand, the batch-type atmosphere firing furnace with a raised and lowered hearth shown in FIG. 13 are provided.

The hearth 13 is raised and lowered by a screw 15 supported by a beam 14 of the pedestal 11 or by a hydraulic cylinder (not shown). When firing the object 3 to be fired, the hearth 13 is guided by the pedestal 11 and a part of it is attached to the furnace body 12. The main body fits into the opening 12b of the main body and rises.

By the way, in the above-mentioned batch type atmosphere firing furnace, in order to increase the internal pressure with a small amount of gas input and obtain a sufficient gas atmosphere effect on the object 3 to be fired, one side 2a of the furnace body 2 and the door 4 are connected. A sealing member 7 made of a material such as silicone rubber or silicone sponge is interposed between the bottom surface 12a of the furnace body 12 and the hearth 13 (in the case of FIG. 3). equipped.

However, the sealing member 7 is
It is constantly pressed against the furnace body 2 or 12 via the door 4 or the hearth 13, and receives heat from the furnace body 2 or 12. For this reason, the sealing member 7 is made of a material with low thermal conductivity such as silicone rubber or silicone sponge.
The temperature of the furnace body 2 increases, causing it to burn out or deform.
There was a problem in that the seal between the door 4 and the furnace body 12 and the hearth 13 deteriorated.

(Object of the Invention) The object of the present invention is to improve the sealing performance between the furnace body and the closing member that closes the opening of the furnace body, to increase the internal pressure with a small amount of gas input, and to achieve a sufficient gas atmosphere effect. It is an object of the present invention to provide a sealing structure for a batch-type atmosphere firing furnace for obtaining fired products.

(Structure of the Invention) For this reason, the present invention includes a sealing plate on the furnace body side that surrounds the opening, projects perpendicularly to the opening end surface of the furnace body, and has a gas passageway reaching from the side surface to the tip. The closing member side is provided with a groove portion for receiving the seal plate. A flexible elastic member is attached to the inside of the groove and protrudes obliquely from the top of both opposing inner walls of the groove toward the bottom of the groove. The tip of the elastic member is brought into close contact. The same gas as that supplied to the furnace main body 1 is introduced into the groove through the gas passage of the seal plate, and the elastic member is urged toward the seal plate and cooled by this gas. That is, in the present invention, the tip of the elastic member attached to the opening of the groove of the closing member is brought into close contact with the side surface of a seal plate protruding from the furnace body, and the elastic member is inserted into the furnace body through the seal plate and into the groove. Gas is introduced, the elastic member is cooled by the gas, and the pressure is used to press the tip of the elastic member against the side wall of the sealing plate, thereby sealing the inside of the furnace main body.

(Effects of the Invention) According to the present invention, the elastic member that seals the inside of the furnace body is cooled by the gas injected into the furnace body, and no large pressure is applied from the closing member, so that the elastic member is deformed. The seal between the furnace body and the closing member can be maintained in good condition for a long period of time.

Further, according to the present invention, if the seal plate and the groove are concentric, it is possible to obtain a batch-type atmosphere firing furnace with a rotary hearth in which the hearth can be rotated while maintaining sealing properties.

(Examples) Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an embodiment in which the present invention is applied to the hearth raising and lowering type batch atmosphere firing furnace shown in FIG.

In FIG. 1, a metal frame 21 having an L-shaped cross section is provided at the peripheral edge of the lower surface 12a of the furnace body 12, and a seal plate 22 is welded to this frame 21. The seal plate 22 is a metal plate (not shown) having a constant width, which is curved into a roughly U-shape at its center.

The seal plate 22 is connected to the opening 1 of the furnace body 12 shown in FIG.
2b, and is welded to the frame 21 at a position corresponding to the position where the seal member 7 is in contact with the seal member 7.

As shown in FIG. 1, the seal plate 22 is provided with oxygen (02), nitrogen (N2), or hydrogen, which is the same gas as the gas injected into the furnace body 12, on the outer side plate 22a near the furnace body 12. A pipe 23 for introducing cold gas such as (N2) or a mixture thereof is attached.

Further, holes 24 having a diameter of about 2 mm are formed at the tip of the seal plate 22 at intervals of fsOcm. This hole 2
Reference numeral 4 refers to a groove 2 provided in the elevating hearth 13, which serves as a closing member to describe the cold gas introduced from the pipe 23.
It is for discharging into 5.

The groove 25 is formed in a groove forming metal fitting 26 having a generally U-shaped cross section, and this groove forming metal fitting 26 is fixed to the elevating hearth 13 by a fixing metal fitting 27. The groove forming metal fitting 26 is attached to the elevating hearth 13 by means of a fixing metal fitting 27 at a position where the center of the groove 25 coincides with the center of the beam seal plate 22 and the seal plate 22 fully enters the inside of the groove 25. Fixed.

The groove forming metal fitting 26 has both side plates 26a.

26b has folded parts 28a and 28b which are folded back diagonally downward at the bottom of the groove part 25. Elastic members 29a and 29b made of a heat-resistant material such as silicone rubber are attached to these folded portions 28a and 28b by means of a tie 30 and a presser plate 31, respectively.

As shown in FIG.
a and 29b have their tips connected to side plates 22a and 22b.
It is separated into two sides and tightly adheres to these side plates 22a and 221) by elastic force. In addition, a predetermined gas such as oxygen, nitrogen, hydrogen, or a mixture thereof is introduced into the groove 25 into the furnace body 12, and at the same time, the pipe 23, the seal plate 22, and the tips of the seal plate 22 are charged. Hole 2
4, a portion of the gas (cold gas) is introduced.

The gas pressure in the groove 25 is maintained at 40 mAq or more, which is higher than the gas pressure of the gas introduced into the furnace body 12.

With such a configuration, the gas injected into the furnace body 12 is as indicated by arrow A. As shown, the lower surface 12a of the furnace body 12
and the elevating hearth 13, and reaches the elastic member 29b that is in close contact with the side plate 22b of the seal plate 22, and pressure A1 is applied to this elastic member 29b. On the other hand, the elastic members 29a and 29b are caused by the gas introduced into the groove 25 from the outside to cause the side plates 22a of the seal plate 22 to 22b.

Therefore, the tips of the elastic members 29a and 29b are connected to the side plate 22a.
, 22b to seal between the furnace body 12 and the elevating hearth 13. A pipe 33 having a valve 32 is attached to the lower part of the side plate 26a, and the pressure A2 of the gas introduced into the groove 25 is adjusted by the valve 32, while the elastic members 29a, 29b
Maintains the cooling effect of

In the above embodiment, the elastic members 29a and 29b are
2, but is in pressure contact with the side plates 22a and 22b of the sealing plate cooled by the passage of cold gas, and is attached to the groove forming metal fitting 26 cooled by the cold gas, so it has elasticity. Member 29a.

29b will not be deformed or scorched by heat,
Good sealing performance can be obtained for a long period of time.

In FIG. 1, a seal plate 22 and a groove forming metal fitting 26 are shown.
If they are formed concentrically, it is possible to obtain a rotary hearth type batch type atmosphere firing furnace in which firing is performed by rotating the elevating hearth 13.

The present invention can also be applied to a batch type atmosphere kiln with a door opening/closing type as shown in FIG.

In this case, a seal plate 22 is attached to one side 2a of the furnace body 2 so as to surround the opening 2b, and an elastic member 29a is attached to the door 4.
, 29b may be provided.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view of an embodiment of the sealing structure of a batch type atmosphere firing furnace according to the present invention, and FIGS. 2 and 3 are a door opening/closing type and a hearth lifting type batch type having conventional sealing structures, respectively. FIG. 2 is a longitudinal cross-sectional view of an atmosphere firing furnace. 2...furnace body, 2a...-side, 2b...
・Opening, 3...Object to be fired, 4...Door,
7... Seal member, 12... Furnace body,
12a...lower surface, 12b...opening,
13... Elevating hearth, 22... Seal plate, 23... Pipe, 24... Hole, 25...
Groove portions, 29a, 29b...elastic members.

Claims (1)

[Claims] (1) A sealing structure for a batch atmosphere firing furnace that seals between the furnace body and a closing member that closes the opening of the furnace body, and the furnace body side has a seal structure that surrounds the opening and an end surface of the opening of the furnace body. The sealing plate is provided with a gas passage that protrudes perpendicularly to the side surface and reaches the tip from the side surface, while the closing member side is provided with a groove portion for receiving the sealing plate, and inside this groove portion there are two opposing inner sides of the groove portion. A flexible elastic member is attached to the upper part of the wall and protrudes diagonally toward the bottom of the groove, and the tips of the elastic member are in close contact with both sides of the seal plate fitted into the groove of the closing member. The same gas as that supplied into the furnace body is introduced into the groove through the gas passage, and the elastic member is urged toward the seal plate and cooled by this gas. Seal structure of batch type atmosphere firing furnace.