JP3134433B2 - Hearth rotating batch furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary hearth batch furnace, and more particularly to a technique for improving a temperature distribution in a firing chamber.

[0002]

2. Description of the Related Art Conventionally, as a hearth rotary batch furnace, as shown in FIGS. 3 and 4, a baking chamber 1 for storing and heating an object to be heated S, and Firing room 1
It is known that the apparatus includes a hearth table 2 that rotates inside the furnace. The hearth table 2 is configured to perform not only a rotation operation but also a lifting operation. That is, the object to be heated S is previously placed on the hearth table 2 outside the furnace, and then the hearth table 2 is raised and the heated object inlet / outlet provided below the firing chamber 1 (shown in FIG. Is heated in accordance with a predetermined temperature condition while being rotated in the firing chamber 1 while being closed.

[0003] When the object to be heated S is, for example, a disc-shaped ceramic molded body for thermistor production, it is placed in a box-shaped firing sagger (not shown). In general, these baking saggers are stacked on each other and placed on the hearth table 2 after being housed. Reference numeral 3 in FIGS. 3 and 4 denotes a furnace body in which a firing chamber 1 is provided, 4 denotes a heater disposed at predetermined positions in the firing chamber 1, and 5 and 6 denote furnace bodies, respectively. 3 is a supply passage and a discharge passage for the in-furnace atmosphere gas provided through the passage 3.

[0004]

In the hearth rotary batch furnace having the above-mentioned structure, the atmosphere gas in the furnace, which has been heated and lightened in specific gravity, rises by convection. The temperature of the upper layer portion tends to be higher than that of the lower layer portion in the furnace 1, and the temperature distribution in the firing chamber 1 becomes uneven. If such a non-uniform temperature distribution occurs, the characteristics of each of the fired ceramic molded bodies will not be uniform, resulting in a serious inconvenience such as a reduction in product yield. It will also be.

The present invention has been made in view of such inconvenience, and an object of the present invention is to provide a rotary hearth batch furnace capable of easily achieving a uniform temperature distribution in a firing chamber.

[0006]

In order to achieve the above object, the present invention comprises a firing chamber for storing and heating an object to be heated, and a hearth table for rotating the object to be heated. A hearth rotary batch furnace, which is provided with a jig for stirring the atmosphere gas in the furnace, which is stacked and placed on the uppermost portion of the object to be heated, and the jig for stirring includes a rotation of the jig. Accordingly, there is provided a blade for sending out the atmosphere gas in the furnace toward the periphery.

[0007]

According to the above construction, the jig for stirring the atmosphere gas in the furnace is rotated by the hearth table together with the object to be heated, and when the stirring jig rotates, the jig is located in the upper layer of the firing chamber. The atmosphere gas in the furnace is disturbed by the rotation of the blades and is sent out to the surroundings. Then, the furnace atmosphere gas sent from the stirring jig collides with the inner wall surface of the firing chamber, and is forced to flow toward the lower part of the firing chamber along the inner wall surface. .

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional view showing a schematic structure of a hearth rotary batch furnace according to the present embodiment, and FIG.
FIG. 2 is a cross-sectional view along the line A. Since the overall configuration of the hearth rotary batch furnace is not fundamentally different from that of the conventional example, the same reference numerals are given to the same or corresponding parts and portions in FIGS. 1 and 2 as in FIGS. 3 and 4. The detailed description here is omitted.

[0010] The hearth rotary batch furnace according to the present embodiment,
A baking chamber 1 for storing and heating the object to be heated S;
And a furnace hearth table 2 for rotating the inside of the firing chamber 1, and a jig 10 for stirring the atmosphere gas in the furnace, which is stacked and placed on the uppermost portion of the object S to be heated. The stirring jig 10 is formed using mullite, alumina, silicon carbide, silicon nitride, or the like having excellent heat resistance and impact resistance, and is a hollow circle placed on the object S to be heated. A plate portion 10a, and blades 11 which are spaced apart from each other at predetermined positions on the hollow disk portion 10a and which project upward.
It is composed of At this time, it is desirable that each of the blades 11 has a curved shape as shown in the drawing so that the in-furnace atmosphere gas can be easily sent to the surroundings as the stirring jig 10 rotates. .

In this embodiment, the stirring jig 10 is shown as being integrally formed, but the invention is not limited to this. For example, the stirring jig 10 is divided as shown by a virtual line in the drawing. It is needless to say that they may be configured by applying different methods to each other. Further, since the stirring jig 10 is placed on the uppermost portion of the object S to be heated, when the object S to be heated is a stack of firing saggers, the stirring jig 10 is placed. Will also function to prevent these collapses. That is, in the hearth rotary batch furnace, the object S to be heated is placed on the hearth table 2 which is moved down in advance and located outside the furnace, and furthermore, the uppermost part of the object S to be heated After the jigs 10 for stirring the atmosphere gas in the furnace are stacked and placed, the object S to be heated and the jigs 10 for stirring are housed in the firing chamber 1 with the raising operation of the hearth table 2. . The object to be heated S stored in the firing chamber 1 is heated by the rotating operation of the hearth table 2 according to a predetermined temperature condition while being rotated, for example, in the direction of arrow C in the drawing. become.

At this time, the stirring jig 10 placed on the heated object S is rotated by the hearth table 2 together with the heated object S, and the stirring jig 10 is rotated. At this time, the furnace atmosphere gas in the upper part of the firing chamber 1 is disturbed by the rotation of the blades 11 and is sent out toward the periphery thereof. Furthermore, the furnace atmosphere gas sent from the stirring jig 10 collides with the inner wall surface 1a of the firing chamber 1,
The fluid is forced to flow along the inner wall surface 1a toward the lower layer in the firing chamber 1.

[0013]

As described above, in the hearth rotary batch furnace according to the present invention, the jig for stirring the atmosphere gas in the furnace is stacked on the uppermost part of the object to be heated rotated by the hearth table. Since the stirring jig rotates with the object to be heated, the atmosphere gas in the furnace in the upper layer of the firing chamber is disturbed by the rotation of the blades provided on the stirring jig, and It will be sent out to the surroundings. Then, the furnace atmosphere gas sent from the stirring jig collides with the inner wall surface of the firing chamber, and is forced to flow toward the lower part of the firing chamber along the inner wall surface.

Therefore, according to the present invention, the forced flow of the atmosphere gas in the furnace in the vertical direction in the firing chamber is ensured, and the temperature distribution and the atmosphere gas in the firing chamber can be easily made uniform. The effect is obtained. Therefore, when the object to be heated is a ceramic molded body or the like, the properties of each of the fired ceramic molded bodies are equal to each other, so that the product yield can be improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a schematic structure of a hearth rotary batch furnace according to an embodiment.

FIG. 2 is a cross-sectional view taken along the line AA of FIG.

FIG. 3 is a longitudinal sectional view showing a schematic structure of a hearth rotary batch furnace according to a conventional example.

FIG. 4 is a transverse sectional view taken along line BB of FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Baking room 2 Hearth table 10 Jig for stirring 11 Blade S Heated object

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F27D 7/04 C21D 1/767 F27B 3/06

Claims (1)

(57) [Claims] 1. A hearth rotary batch furnace comprising a firing chamber (1) for storing and heating an object to be heated (S), and a hearth table (2) for rotating the object to be heated (S). And a jig (10) for stirring the atmosphere gas in the furnace, which is stacked and mounted on the uppermost portion of the object to be heated (S), and the jig (10) includes A rotary hearth type batch furnace, comprising a blade (11) for sending out an atmosphere gas in the furnace toward the periphery as the tool rotates.