JPH01181086A - Ceramic chain for continuous calcine furnace - Google Patents

Abstract

PURPOSE:To prevent the poor appearance as well as the chemical reaction of a porcelain and calcine the same uniformly, by carrying an article to be calcined, which is put on neighboring sleeves and whose side surface is abutted against the sleeves, through the inside of a furnace body while being rotated. CONSTITUTION:A thick disc-type ceramics compact 2 is arranged between the neighboring sleeves 22, 22 of a ceramics chain 21 and the outer side surfaces of the compact 2 are abutted against the side surfaces of the sleeves 22. Respective rolling wheels 22a, 22b of the sleeves 22, 22 are pressed against the floor surface of the central tube of a furnace and the chain 21 is conveyed in the direction of an arrow sign A3; then, the rolling wheels 22a, 22b of the ceramics chain 21 are rotated in the direction of an arrow sign A4. Accordingly, the ceramics compact 2 is rotated in the direction of an arrow sign A5. The ceramics compact 2, put on the chain 21, is transferred sequentially through the inside of the central tube of the furnace in accordance with the transfer of the chain 21. The ceramics compact 2 passes continuously through the inside of the central tube of the furnace while being rotated, whereby the compact 2 may be calcined uniformly.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a ceramic chain for a continuous firing furnace used for firing relatively large ceramic products such as ceramic dielectrics used in high-voltage capacitors and the like.

(Prior Art) Generally, as the withstand voltage of a ceramic capacitor increases, the shape of the ceramic dielectric used therein increases.

Conventionally, for example, the diameter was 50@lφ and the thickness was 2°ral.
When firing a ceramic dielectric material for a large high-voltage capacitor that has an Iφ disc shape and contains lead oxide or bismuth oxide, it is necessary to use a rectangular-shaped sac made of alumina or mullite, as shown in Figure 7. A ceramic molded body 2 formed by press molding a ceramic material into a disc shape is housed inside. Then, such boxes are stacked in multiple stages as shown in Fig. 8, and are used in a continuous tunnel furnace 3 as shown in Fig. 9 and Fig. 1θ, or a batch-type vertical furnace (
Not shown. ) is fired.

The tunnel furnace 3 has a tunnel-shaped furnace body 5 on the base 4.
are arranged horizontally. The boxes 1 stacked in multiple stages on the base plate 9 pass from the outside of the inlet 6 of the furnace body 5, through the inside of the furnace body 5, and toward the outside of the outlet lower part of the furnace body 5.
The bushing 8 automatically bushes first into the preheating zone following the inlet 6 of the furnace body 5, as indicated by the arrow A1. After burning the binder (molding aid) in the ceramic molded body 2 in this preheating zone (depine mite removal process),
The base plate 9 is pushed into a firing zone following the preheating zone of the furnace body 5, and the ceramic molded body 2 is fired. When this firing is completed, the ceramic molded body 2 is bushed into a cooling zone following the firing zone of the furnace body 5, cooled, and then pulled out from the furnace body 5.

On the other hand, although not specifically shown, in a vertical furnace, boxes 1 containing ceramic molded bodies 2 to be fired are stacked on a plywood board placed on the hearth of the furnace body. Then, the ceramic molded body 2 is heated by a heater made of silicon carbide (SiC) or the like disposed inside the furnace body, and fired according to a predetermined firing program.

By the way, as mentioned above, if the ceramic molded body 2 is housed in the box 1 and fired in the tunnel furnace 3 or the vertical furnace, jigs such as the base plate 9 and the box 1 are required, which increases the cost. Another problem was that the heat required to heat the jig resulted in energy loss.

In addition, by using the jig, the effective volume inside the furnace becomes larger compared to the volume occupied by the ceramic molded body 2, so
There were also problems in that the temperature distribution and atmosphere inside the oven became non-uniform, leading to compositional deviations in the baked product and deterioration of properties, and that the firing furnace also became large.

Furthermore, the ceramic molded body 2 also had the problem that its own weight deformed the portion thereof that contacted the bottom surface of the box 1 during firing.

Therefore, for example, as shown in FIG.
A ceramic belt conveyor 13 is provided that moves continuously in the direction indicated by arrow A within the furnace body 12, and the ceramic molded body 2 is placed on this belt conveyor 13. In some cases, the ceramic molded body 2 is transported and fired during the process. A furnace core tube 15 is disposed within the furnace body 12, and a heater H is disposed outside thereof. The conveyor belt 13 is this furnace core tube 1
Move within 5.

The belt conveyor 13 is shown in FIGS. 12 and 13 (a).
As shown in FIG. 13(b), the unit members 16a and 16b (see FIGS. 13(a) and 13(b)) are square shaped and made of alumina or mullite ceramic material. A projection 17 formed on the unit member 16b and having a circular cross section is fitted into the unit member 16a from the axial direction thereof, and a recess 18 is formed in which the projection 17 is prevented from coming out in the axial direction. There is.

Thereby, the unit members 16a and 16b can be bent to a certain degree by the projections 17 and the recesses 18. In the belt conveyor 13, a large number of the above two types of unit members 16a and 16b are connected to form an endless belt, as shown in FIG. Then, on this belt conveyor 13, as shown in FIG. 14, the ceramic molded body 2 is directly placed horizontally or vertically.

By the way, when the belt conveyor 13 as described above is used, when the ceramic molded body 2 is placed horizontally on the belt conveyor 13, the contact area between the ceramic molded body 2 and the belt conveyor 13 is large, and the ceramic molded body 2 and the belt conveyor 13 have a large contact area. There was a problem in that chemical reactions were likely to occur between the two.

Furthermore, if the ceramic molded body 2 is placed vertically on the belt conveyor 13, the appearance of the ceramic molded body 2 tends to be poor at the point of contact with the belt conveyor 13, and the temperature distribution becomes uneven in the large-shaped ceramic molded body 2. There was a problem.

Furthermore, when the ceramic molded body 2 is placed vertically, the ceramic molded body 2 tends to move on the belt conveyor 13 and is unstable, and when the ceramic molded body 2 is placed horizontally, there is a problem that the number of processing is reduced.

(Objective of the Invention) The object of the present invention is to maintain a uniform ambient temperature around a ceramic object to be fired, and to prevent poor appearance and chemical reactions of the porcelain while rotating the porcelain without using a jig such as a box. It is an object of the present invention to provide a ceramic chain for a continuous firing furnace that prevents the firing of porcelain and enables uniform firing of porcelain.

(Structure of the Invention) Therefore, the present invention has a tunnel-shaped internal space leading from one end opening side to the other end opening side, and the object to be fired is placed between the one end opening and the other end opening of this internal space. A ceramic chain for conveying a workpiece to be fired from the one end opening side to the other end opening side through the internal space of the furnace body, which is set to a temperature curve suitable for firing the workpiece, the ceramic chain having a disk shape. A cylindrical ceramic sleeve with coaxial rolling wheels spaced apart from each other at intervals greater than the thickness of the object, and a ceramic shaft with a circular cross section that is inserted through the sleeve and rotatably supports the sleeve. and a ceramic shaft fixing plate that fixes the shaft member at a protruding portion of the sleeve from the rolling wheel and fixes the shaft member at an interval smaller than the diameter of the object to be fired. The adjacent shaft fixing plates are rotatably coupled to each other by the shaft member, and the rolling wheels are placed on the adjacent sleeves by rolling on the hearth in the furnace body, so that the side surfaces thereof are attached to the sleeves. It is characterized in that the object to be fired which is in contact with the furnace body is conveyed through the furnace body while rotating.

When the ceramic chain moves inside the hearth tube from the inlet to the outlet of the hearth tube, the rolling wheels of the sleeve of the ceramic chain come into contact with the hearth and rotate. Along with this rotation, the disk-shaped object to be fired, which is placed on the sleeve that is fitted onto the adjacent shaft members of the ceramic chain with its outer peripheral surface in contact with it, rotates and moves inside the furnace core tube. transported.

In this process, the object to be fired is heated and fired.

(Effects of the Invention) According to the present invention, the object to be fired rotates during the process of being conveyed in the furnace core tube, and is fired by receiving heat directly from the furnace body, so jigs such as boxes and base plates are is not required, and costs can be reduced in terms of jigs and power consumption. Further, according to the present invention, since the object to be fired is fired while rotating,
Uniform porcelain firing is possible without the appearance defects and chemical reactions that occur when the object to be fired is placed directly inside the box.

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

An embodiment of the ceramic chain for continuous firing furnaces according to the present invention is shown in FIGS. 1 and 2. Further, its constituent parts are shown in FIGS. 3, 4, and 5.

, the chain 21 includes a ceramic sleeve 22, a ceramic shaft member 23 that rotatably supports the ceramic sleeve 22, and a ceramic shaft member 23.
3 and a fixing plate 24 made of ceramic.

As shown in FIGS. 5(a), 5(b) and 5(c), the sleeve 22 is rolled at a distance d greater than the thickness of the ceramic molded body 2 having a disc shape (see FIG. 7). It is provided with driving wheels 22a and 22b coaxially.

A hole 22c through which the shaft member 23 is inserted is formed in the axial center of the sleeve 22.

As shown in FIGS. 3(a), (b) and (c), the shaft member 23 has a hole 22c in the sleeve 22.
The cross section is circular and has a diameter slightly smaller than the inner diameter of the tube. The shaft member 23 is connected to the hole 22 of the sleeve 22.
c and is fixed to the fixing plate 24.
2 is rotatably supported. The shaft member 23 has a locking portion 23 at one end of which the diameter is larger than that of the other portion.
It has a. Further, the other end of the shaft member 23 also has a locking portion 23b having a larger diameter than the other portions.

However, this locking portion 23b is cut out at two locations facing each other so that the cutout surfaces are parallel to each other.

On the other hand, the fixed plate 24 is attached to the rolling ring 22a of the sleeve 22, as shown in FIGS. 4(a) and 4(b).

It is a flat plate having a width smaller than the diameter of 22b. The fixing plate 24 has a short axis approximately equal to the diameter of the shaft member 23 and a long axis at a locking portion of the shaft member 23 at intervals smaller than the diameter of the ceramic molded body 2 (see FIG. 7). An elliptical locking hole 24a having a diameter slightly larger than that of 23a and 23b.

24a is formed.

The sleeve 22, shaft member 23, and shaft fixing plate 24 described above are assembled into a continuous ceramic chain 21 as shown in FIG.

That is, each of the shaft members 23 is first inserted into the locking holes 24a, 24a of the two shaft fixing plates 24.24, and then into the holes 22c of each sleeve 22. The locking portions 23b of each sleeve 22 of each shaft member 23 are connected to a pair of adjacent shaft fixing plates 24.
24 locking holes 24a.

24a, and each of the shaft members 23 is rotated 90 degrees. As a result, the locking portion 23b of each sleeve 22
Therefore, the shaft fixing plate 24.2 on this locking portion 23b side
4 is prevented from being removed (see Figure 2). The adjacent shaft fixing plates 24, 24 are connected to each shaft member 23.
are rotatably connected using the connecting shaft.

With such a configuration, the ceramic chain 21
As shown in FIG. 2, a thick disk-shaped ceramic molded body 2 is arranged between adjacent sleeves 22.22, and its outer surface abuts the side surface of the sleeve 22.22. Each rolling wheel 22a, 22b of the sleeve 22.22
Also, due to the weight of the chain 21 and the ramic molded body 2, it is pressed against the floor surface of the furnace core tube 15. As a result, when the chain 21 is conveyed in the direction of arrow A in the furnace core tube 15 as shown in FIG. 2, the rolling wheels 22a and 22b of the ceramic chain 21 are moved in the direction of arrow A4. Rotate. Therefore, the ceramic molded body 2, which is arranged between adjacent sleeves 22, 22 of the chain 21 and whose outer surface is in contact with the side surface of the sleeve 22, rotates in the direction of arrow A.

As a result, the ceramic molded bodies 2 mounted on the chain 21 are sequentially transported into the furnace core tube tS (see FIG. 11) as the chain 21 is transported.

This furnace core tube I5 includes a ceramic molded body 2 and a chain 21.
Since the diameter is small enough to allow the passage of the porcelain, the atmosphere and temperature around the porcelain can be kept uniform.

On the other hand, as the chain 21 moves, the sleeve 22 rotates as shown in FIG. 2, and at the same time, the ceramic molded body 2 does not rotate and passes continuously through the furnace core tube 15. In this process, the ceramic molded body 2 can be fired uniformly without using jigs such as a box or a base plate, and the ceramic molded body 2 can be fired uniformly without causing any appearance defects or chemical reactions due to contact with the sleeve 22. It can be fired to

Next, another embodiment of the present invention is shown in FIG.

The ceramic chain 31 shown in FIG. 6 has the length of the shaft member 23 of the ceramic chain 21 shown in FIG. 1 approximately doubled, and two sleeves 22 are rotatably attached to each shaft member 23. 2 can be fired in two rows.

If such a ceramic chain is used, a large number of objects 2 to be fired can be processed at one time.

Three or more sleeves 22 can also be attached to the shaft member 23.

[Brief explanation of the drawing]

Fig. 1 is a plan view of an embodiment of the ceramic chain according to the present invention, Fig. 2 is an explanatory diagram of the operation of the ceramic chain of Fig. 1, and Figs. 3 (a), (b), and (c) are respectively 1, and FIGS. 4(a) and 4(b) are a front view, a top view, and a top view of the shaft fixing plate of the ceramic chain in FIG. 1, respectively. Figures 5 (a), (b) and (c) are the left side view, top view and right side view of the ceramic chain in Figure 1, and Figure 6, respectively.
The figure is a plan view of a modified example of the ceramic chain in Figure 1, Figures 7 and 8 are illustrations of conventionally used boxes, respectively, Figure 9 is an illustration of a conventional continuous firing furnace, and Figure 10 is an illustration of a conventional continuous firing furnace. The figure is a cross-sectional view of the continuous firing furnace shown in Figure 9 taken along the line ■-■. Figure 11 is an explanatory diagram of a continuous firing furnace using a conventional belt conveyor. Figure 13 (
a) and (b) are explanatory views of the components of the belt conveyor shown in FIG. 12, respectively. FIG. 14 is an explanatory view showing the state in which the belt conveyor shown in FIG. 12 is used. 2... Ceramic molded body, 21... Ceramic chain, 22... Sleeve,
22a, 22b...Rolling wheel, 23...Shaft member, 24...Shaft fixing plate, 31...Ceramic chain patent applicant Murata Manufacturing Co., Ltd. Attorney: Patent attorney (mentioned above), 2nd person other than Ao Figure 1 Figure 2 Figure 3 (a) (b) (c) Figure 4 Figure 5 E Figure 6 Figure 8 Figure 12 Figure 13 (o) (b)

Claims (1)

[Claims] (1) It has a tunnel-shaped internal space leading from one end opening side to the other end opening side, and a temperature curve suitable for firing the object to be fired is set between the one end opening and the other end opening of this internal space. The ceramic chain conveys the object to be fired through the internal space of the furnace body from the one end opening side to the other end opening side, the ceramic chain preferably having an interval larger than the thickness of the disk-shaped object to be fired. a cylindrical ceramic sleeve coaxially equipped with a rolling wheel; a ceramic shaft member with a circular cross section that is inserted into the sleeve and rotatably supports the sleeve; and a ceramic shaft fixing plate that fixes the shaft member at a protruding portion from the rolling wheel and fixes the shaft member at an interval smaller than the diameter of the object to be fired, and adjacent shaft fixing plates They are rotatably connected to each other by a shaft member, and as the rolling wheels roll on the hearth in the furnace body, the objects to be fired that are placed on the adjacent sleeves and whose side surfaces are in contact with the sleeves are fired. A ceramic chain for a continuous firing furnace, characterized in that it is conveyed through the furnace body while rotating.