JPH06221765A - Kiln for ceramic - Google Patents

Abstract

PURPOSE:To provide a kiln for ceramics in which raw ceramic material can be forwarded at a rate alterable as desired, the condition set for each heating zone can be maintained, and moreover the temporary firing and the main firing of raw ceramic material can be carried out in a continuous process. CONSTITUTION:A kiln for ceramics 1 has a furnace body 3 having heating zones 2 into which the furnace is longitudinally divided, a plurality of tubular furnace cores 4 each of which is longer than the respective heating zone 2 and differs in inner diameter (d) from the others, and endless drives 5 in a plurality of sets which support the tubular furnace cores 4, each set holding one tubular furnace core at its two ends with its circumferential side on themselves in a manner of suspension and designed to revolve independent of the other sets. The tubular furnace cores 4 are so arranged that from the loading end 3a of the furnace body 3 they become enlarged in inner diameter (d) toward the discharging end 3b, that is, a succession of an arrangement that the end 4b on the discharging side of a tubular furnace core 4 having a smaller inner diameter (d) is inserted in the end 4a on the loading side of a tubular furnace core 4 having a larger inner diameter (d). Furthermore, a gas-discharging pipe 12 is provided between each two heating zones 2 where the differing inner diameters (d) between two adjoining tubular furnace cores 4 form a gap 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic firing furnace (hereinafter referred to as firing furnace) used for firing a ceramic raw material, and more particularly to a furnace core tube structure thereof.

[0002]

2. Description of the Related Art Conventionally, when firing a ceramic raw material such as a barium titanate-based dielectric material or a lead zirconate titanate-based piezoelectric material, a rotary kiln as shown in FIG. It is general to use a firing furnace 20 having a structure called. That is,
This firing furnace 20 is a ceramic raw material (not shown).
A furnace body 22 having a plurality of heating zones 21 divided along the longitudinal direction, which is the feeding direction of, and a cylindrical shape that is arranged in an inclined shape from the charging end 22a toward the extraction end 22b and is rotationally driven. And a core tube 23 of
In each heating zone 21, a heater 24 having a temperature controllable structure is provided. Reference numeral 25 in the drawing denotes a roller for supporting and rotating the core tube 23.

[0003]

By the way, in the above-described conventional firing furnace 20, since the furnace core tube 23 inserted through the furnace body 22 is an integral body, the feed rate of the ceramic raw material is It is natural that the furnace body 22 is constant from the charging end 22a to the extracting end 22b, and the setting condition for each heating zone 21 is set differently as necessary, but the setting is made for each heating zone 21. It was not possible to change the feed rate of the ceramic raw material according to the conditions. Further, each of the heating zones 21 in the firing furnace 20 is thermally based on heat conduction through the core tube 23 which is integrated despite being partitioned from each other along the longitudinal direction of the furnace body 22. These influences on each other, and since only the charging end 22a and the extraction end 22b of the furnace body 22 are opened to the outside, it is difficult to maintain the setting conditions of each heating zone 21, and the calcination of the ceramic raw material is difficult. In addition, there is a problem that the main firing cannot be continuously performed.

The present invention was devised in view of such inconvenience, and the feed rate of the ceramic raw material in each heating zone can be arbitrarily changed, and the setting condition for each heating zone can be continuously maintained. It is an object of the present invention to provide a firing furnace that can perform the preliminary firing and the main firing of the ceramic raw material continuously.

[0005]

The firing furnace according to the present invention comprises:
In order to achieve such an object, a furnace body having a plurality of heating zones sectioned along the longitudinal direction, a plurality of furnace core tubes longer than each heating zone and having different inner diameters, and The furnace core tube is provided with a plurality of sets of endless transmissions that are hung and supported at the outer circumferences of both ends of the furnace core tube, and each set is rotatably driven separately. It is arranged in the order of increasing inner diameter toward, and the extraction side end of the furnace core tube with a small inner diameter is successively inserted into the charging side end of the furnace core tube with a large inner diameter. ,further,
It is characterized in that an exhaust pipe is provided between each heating zone in which a gap generated between the inner diameters of the furnace core pipes continuous with each other is located.

[0006]

According to the above construction, each of the furnace core tubes is arranged after being divided into each heating zone, and the furnace body is installed by adjusting the length of each endless transmission. It is supported as an inclined shape from the entrance end to the extraction end, and is then separately rotated. Therefore, the ceramic raw material charged inside the furnace core tube located on the charging end side of the furnace body is positioned on the extraction end side of the furnace body while being successively delivered by each of the furnace core tubes whose inner diameter is increasing. It will be sent to the furnace core tube.

Therefore, by adjusting the rotation speed of each set of endless transmissions supporting each furnace core tube, the feed rate of the ceramic raw material in each heating zone is changed. At this time, since the furnace core tubes are divided from each other and the exhaust pipe is provided between the heating zones, the thermal zones from other feasible zones are different from each other. It is possible to maintain the necessary set conditions for each heating zone.

[0008]

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

FIG. 1 is a vertical cross-sectional side view showing a simplified overall structure of a firing furnace according to this embodiment, and FIG. 2 is a partial perspective view showing a main structure of a furnace core tube. Reference numeral 1 in FIG. A firing furnace is shown.

The firing furnace 1 according to the present embodiment has a plurality of (three in the figure) heating zones 2 divided along the longitudinal direction which is the feeding direction of the ceramic raw material (not shown) to be fired. The furnace body 3 and the plurality of heat-resistant alloys each having a cylindrical shape longer than the zone length of each heating zone 2 and having different inner diameters d (3 in FIG.
Main core tube 4 and a plurality of sets of endless transmissions 5 each of which is made of a ceramic chain or a ceramic cord, which is hung and supported on the outer circumferences of both ends of each core tube 4 and is individually rotated. Is equipped with. Here, in order to set the firing temperature of the ceramic raw material to a low temperature range of 1000 ° C. or lower, it is common to use the furnace core tube 4 made of a heat-resistant alloy such as SUS or Inconel, and the firing temperature is 1000 to 14
In the high temperature range of about 00 ° C., the furnace core tube 4 made of ceramic such as mullite or alumina is used.

At this time, each of the furnace core tubes 4 is provided at each position corresponding to each heating zone 2, while each of the endless transmissions 5 supporting each furnace core tube 4 is a furnace. The set is pierced through the ceiling part of the body 3 and is extended to the outside, and is rotationally driven synchronously for each set through a transmission shaft 7 connected to a rotational drive source 6 such as an electric motor. It has become so. In each heating zone 2 of the furnace body 3, a heater 8 having a temperature controllable structure similar to the conventional example is arranged.

Further, each of the furnace core tubes 4 is suspended in an inclined shape from the charging end 3a of the furnace body 3 toward the extraction end 3b by adjusting the length of each of the endless transmissions 5 forming a pair. On the other hand, the extraction side end of the furnace core tube 4 is arranged in the order of increasing the inner diameter d from the charging end 3a of the furnace body 3 toward the extraction end 3b while being supported downward. 4b is a charging-side end 4a of a thick furnace core tube 4 having an inner diameter d
In contrast, they are sequentially inserted by a length of about 150 mm so that they are in a line with each other and are continuous. At this time, a ring 9 having a width of 20 to 30 mm may be fitted along the inner peripheral surface of the charging-side end 4a of the furnace core tube 4 having a large inner diameter d. If fitted, it can prevent backflow (spillage) of the ceramic raw material.
Further, here, when inclining each furnace core tube 4,
It is also possible to arrange the transmission shaft 7 and the rotary drive source 6 for suspending and supporting a pair of endless transmission bodies 5 having substantially the same length so as to have a predetermined inclination.

Therefore, between the core tubes 4 having different inner diameters d, that is, between one extraction side end portion 4b and the other charging side end portion 4a, only about 30 to 50 mm along the radial direction. The separated gap 10 is formed. In addition, as shown in FIG. 2, along the circumferential direction of the outer circumferences of both ends of each furnace core tube 4, as shown in FIG.
The anti-slip projections 11 located at both sides of the endless transmission 5 are attached in a state of being separated from each other.

Further, an exhaust pipe 12 drawn to the outside of the furnace body 2 is provided between each heating zone 2 in which a gap 10 formed between the inner diameters d of the furnace core tubes 4 connected to each other is located. There is. Therefore, the exhaust gas (not shown) discharged from each furnace core tube 4 is discharged to the outside of the furnace after passing through the exhaust pipe 12 for each heating zone 2.
It should be noted that each of these exhaust pipes 12 can be used for introducing an atmospheric gas adjusted to the required components, if necessary during firing of the ceramic raw material.

That is, in the firing furnace 1 configured as described above, each of the furnace core tubes 4 constituting the firing furnace 1 is divided for each heating zone 2 and arranged in an inclined shape so as to be rotationally driven at an arbitrary rotation speed. Will be done. Therefore, the furnace body 3
The ceramic raw material charged in the frontmost furnace core tube 4 located on the charging end 3a side of the furnace body 3 is sequentially transferred by each of the furnace core tubes 4 whose inner diameter d increases, and the extraction end 3b of the furnace body 3 is To the furnace core tube 4 located on the side, and while being sent through the furnace core tubes 4 and fired, discharged from the final stage furnace core tube 4 to the outside of the furnace body 3. become.

[0016]

As described above, according to the firing furnace of the present invention, each of the furnace core tubes arranged corresponding to each heating zone is suspended and supported by a set of endless transmission bodies. Therefore, it is possible to arbitrarily change the feed rate of the ceramic raw material in each heating zone by adjusting the rotation speed of each of these endless transmission bodies. Also,
At this time, each of the furnace core tubes is divided from each other, and
Since an exhaust pipe is provided between each heating zone, thermal effects from other possible zones will not be exerted on each heating zone, and as a result, the necessary setting conditions will be maintained for each heating zone. Not only will it be possible to continue
It is also possible to obtain the effect that the preliminary firing and the main firing of the ceramic raw material can be continuously performed.

[Brief description of drawings]

FIG. 1 is a vertical side view showing a simplified overall structure of a firing furnace according to an embodiment.

FIG. 2 is a partial perspective view showing a main structure of a furnace core tube according to the present embodiment.

FIG. 3 is a vertical sectional side view showing a simplified overall structure of a firing furnace according to a conventional example.

[Explanation of symbols]

 1 Firing Furnace (Ceramic Firing Furnace) 2 Heating Zone 3 Furnace Body 3a Charging End 3b Extraction End 4 Furnace Core Tube 4a Charging Side End 4b Extraction Side End 5 Endless Transmission Body 10 Gap 12 Exhaust Pipe d Inner Diameter

Claims (1)

[Claims] 1. A furnace body (3) having a plurality of heating zones (2) divided in the longitudinal direction, and a plurality of furnace bodies (3) longer than each heating zone (2) and having different inner diameters (d) from each other. Of the furnace core tube (4), and a plurality of sets of endless transmissions (5) each of which is rotatably driven separately by suspending and supporting the outer periphery of both ends of each furnace core tube (4), Each of the furnace core tubes (4) has a charging end (3) of the furnace body (3).
The inner diameter (d) is arranged in the order of increasing from a) toward the extraction end (3b), and the extraction side end (4b) of the furnace core tube (4) having a small inner diameter (d) is the inner diameter (d). d) is inserted into the charging side end portion (4a) of the thick furnace core tube (4) and is continuously connected. Further, it is generated between the inner diameters (d) of the furnace core tubes (4) that are continuous with each other. A ceramic firing furnace, characterized in that an exhaust pipe (12) is provided between each heating zone (2) in which the gap (10) is located.