JPH0729833B2 - Continuous production equipment for hollow ceramic plates - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention forms a hollow continuous body by continuously extruding a raw material containing clay as a main component, dries it in a short time, and runs the continuous body. The present invention relates to an apparatus for continuously manufacturing hollow porcelain plates by feeding them to a firing furnace that cuts them to a constant length with a cutter and then fires them in a short time.

[Conventional technology]

For roof tiles and tiles, a continuous molding strip sent from a molding machine is cut into short pieces, and further shaped by pressing, etc., and dried,
It was manufactured by firing, filling a mold with material, molding it by pressing, and then drying and firing. It has also been known to use a microwave heater and a far infrared heater device for reducing the drying time. Moreover, a tunnel dryer, which is not easy to control the temperature, was used for firing.

[Problems to be solved by the invention]

In this type of device, it takes several days for the drying and firing steps, so drying is performed in a continuous body in terms of productivity, cost and location.
This could not be cut into a predetermined length and fired. Further, in the conventional apparatus, since the uncured roof tiles and tiles are dried from the surface, there is a disadvantage that the roof tiles and tiles are twisted or cracked during drying and firing. In addition, in the conventional device, the extruded product immediately after being extruded is soft, so it must be cut into short pieces and dried, and long pieces cannot be formed. I could only produce In addition, in the conventional manufacturing method and apparatus, since the extruded hollow molded body is dried by the waste heat of the firing furnace, it takes several days to dry since it is dried from the surface of the extruded hollow molded body, and it takes about 8 hours for firing. was there. Moreover, in the conventional method of this kind, it was not possible to construct an integrated line from extrusion to drying or a firing furnace. In other words, the production of this line had the disadvantages of enormous cost, vast land, and high energy costs.
In addition, when the hollow molded body is simply dried by microwaves or the like and the drying time is to be significantly shortened, an increase in the water vapor pressure in the hollow portion and the occurrence of dew condensation, the drying degree of the inner wall and the outer surface of the hollow portion If there is not a considerable thickness due to the displacement, there is a defect that explosion, cracking, warpage, deformation such as twisting occurs. In addition, microwaves need to raise the temperature to 130 ° C or higher in order to reduce the water content of the extruded product to 1% or less.
There was considerable time and energy loss to raise to this temperature. There is also a method of drying by using far infrared rays instead of microwaves, but heating the extruded body to 130 ° C or higher takes a much shorter time than microwaves, but there is a weakness that the drying time becomes long. there were. Moreover, above 2
In the drying device using the device, a large amount of water vapor generated during drying is prevented from dew condensation, and there are various problems in the transport structure during drying of the material to be dried, such as deformation due to friction resistance between the material to be dried and the conveyor belt, long There was non-uniform heating of microwaves on the scale.

[Means for solving problems]

The present invention, in order to eliminate such defects, a conveying unit that smoothly transfers the extruded hollow molded article to the next step after the extruder, and then 1/3 of the moisture content of the continuous strip-shaped extruded hollow molded article. Microwave heater for evaporating the water content in a short time (about 5 to 30 minutes), and a far infrared heater device for reducing the water content of the extruded hollow molded body to 1% or less in a short time such as about 5 to 30 minutes. In addition to arranging in this order, the steam that accumulates inside the hollow part during heating is blown off by the air (air, dry air) blown from the outlet provided in the core of the extruder to reduce the steam pressure and In addition to increasing the heating efficiency of, the water content in the hollow part and the surface layer of the extruded hollow molded body is averaged by eliminating the dew condensation occurring in the hollow part, and the steam in the microwave heater space and the steam on the surface of the extruded hollow molded object And then bond it to the above surface. Preventing dew and condensation on the inner wall of the heated space, the inner and outer wall surfaces of the extruded hollow molded body are constantly blown off with air to keep the drying efficiency and drying time at 1 / 10-300th. It is possible to continuously dry a hollow body of a continuous body with a device that is much more compact than before without shortening, cracking, warping, deformation such as twisting of the dried object, or explosion.
Next, this dried continuous body is cut into a predetermined length and fed to a roller hearth kiln with easy temperature control and fired in a short time to make a hollow porcelain plate free from cracks, twists, warps and bends at low cost. It is intended to provide a continuous production apparatus for hollow porcelain plates that can be mass-produced in time.

〔Example〕

Hereinafter, an embodiment of a continuous production apparatus for hollow porcelain plates according to the present invention will be described in detail with reference to the drawings. 1 (a) and 1 (b) are explanatory views showing a typical example of the above apparatus. In the figure, reference numeral 1 is an extruder, and a raw material containing clay as a main material is introduced through a die 2 and a core 3 as shown in FIGS. 2 (a) and 2 (b), for example, FIGS. The extrusion hollow molded body A having a cross-sectional shape having a hollow portion shown in FIG. 4) is continuously extruded. For example, the extrusion speed is about 200 to 2000 mm / min although it varies depending on the thickness and width of the extrusion hollow molded body A. To further explain, the core 3 includes a large number of outlet portions 4 and a common portion 5.
And a connecting pipe 6 for supplying air from the outside or exhausting air and water vapor from the inside,
The outlet portion 4 is formed as a hollow body having the same cross-section as the hollow portion a of the extruded hollow molded body A, and the extruded hollow molded body A
It is formed integrally with the common portion 5 so as to correspond to the arrangement of the hollow portions a. In addition, the core 3 is formed from the tip 3a to the end 3b, for example, so that the clay extruded from the extrusion port 1'of the extrusion molding machine 1 can be extruded from the die 2 without interruption by a continuous body having a hollow portion a of a predetermined shape. It is formed in a streamlined shape. Further, the hollow portion 3c of the core 3 is supplied with a required amount of one or more kinds of air, dry air, wet air, warm air, etc. from a pump 7 installed outside, or discharges water vapor in the hollow portion a. In addition to promoting drying of the hollow portion a of the extruded hollow molded article A that is difficult to dry,
It functions to eliminate adverse effects such as deformation at that time. In addition, the above-mentioned clay is a natural product and has different components depending on each production site, and these advantages and disadvantages are mutually offset to obtain a predetermined mixed clay. As a specific example thereof, porcelain stone, feldspar, kaolinite, halosite, metahalosite, kibushi clay, frog eye clay, Shigaraki clay, chamotte, etc. are crushed and added with water and kneaded. If necessary, this clay may be ironed by a magnet. Reference numeral 9 denotes a plate feeding unit, which is, for example, a flea roller 10, or at least one type such as a drive belt 11 (not shown) synchronized with an extruding device, or a combination thereof as shown in the drawing. It is intended to be sent to the next process without deformation. Reference numeral 12 denotes a microwave heater having an oven continuous structure, which mainly permeates into the inside of the extruded hollow molded body A and converts the microwave B into heat energy without requiring time for heat conduction, and from several seconds. It is for generating heat in a few minutes to evaporate the water in the clay. The extruded hollow molded article A contains about 22 to 15% by weight of water, and has the ability to evaporate, for example, 5 to 10%. In particular, this type of extruded hollow molded article A has a water content of 5
The volume shrinks up to about 8%, but if the water content is less than that, the volume does not shrink. Therefore, the microwave heater 12 will be described in detail. A waveguide 13 for guiding the microwave B oscillated from a microwave oscillator (not shown) to a required location and a reflector 14 for reflecting the guided microwave B. A rotary blade 15 for agitating the reflected microwave B, and a fli-roller conveying unit 16 configured to move the extruded hollow molded body A at an extruding speed but to cause dielectric but not spark.
In addition, the inlet / outlet 17, 18 of the extruded hollow molded body A and the air inlet / outlet 20 for sucking a large amount of air C and the like from the heated space 19 and supplying the heated space 19 to the heated space 19 and the microwave B are external. It is composed of an enclosure 21 which is enclosed so as not to leak to the. The inlets and outlets 17 and 18 are formed to have a structure and length that also function as a filter that prevents the microwave B from leaking to the outside. Further, the heated space 19 for heating the extruded hollow molded body A varies depending on the purpose, but is, for example, about 1 to 5 m.
It is a place. Further, in the fli-roller transport unit 16, the microwave B, air C, etc. are uniformly radiated or blown onto the extruded hollow molding A from the front, back, and side surfaces,
When the extruded hollow molded article A is dried, the whole is contracted by about 10%, so that the extruded hollow molded article A can be conveyed while absorbing this. To illustrate one example,
As shown in FIGS. 4 (a) and (b), the fixed core rod 22
A pipe-shaped flee roller 23 made of Teflon, a core rod support 24 as shown in FIG. 5, and a shield plate 25 provided as necessary.
It is composed of and. To further explain, in FIG. 4 (a), the frill roller 23 is divided into three parts to reduce the resistance when passing through the extruded hollow molded article A, and FIG. 4 (b) shows a flier roller 23 'composed of one piece. Also, a core rod support
Reference numeral 24 is a through hole 24a formed so that the microwave B is also irradiated from the back surface of the extruded hollow molded body A. In addition,
When the extruded hollow molded body A is a long body, the shielding plate 25 suppresses the irradiation of the microwave B at the upper side and both side ends in the longitudinal direction at a high density to achieve uniform heating. It is useful. The air inlet / outlet 20 is connected to an air cycle pump 7 that can blow or suck air (including dry air, warm air, hot air, and air) such as a compressor and a ring blower. Reference numeral 26 denotes a far infrared heater device for raising the temperature of the extruded hollow molded article A to 130 ° C. or more in order to reduce the water content of the extruded hollow molded article A to 1 to 0%. It is composed of a transport mechanism 27 composed of more than one kind, a far infrared heater 28 and a heat insulation box 29, and the heating zone is about 2 to 10 m. Of course, the heating zone varies depending on the thickness, width and extrusion speed of the extruded hollow molded article A that has become a semi-dried body. Reference numeral 30 denotes a traveling cutter, which cuts the dried extruded hollow molded article A into a predetermined length. Reference numeral 31 denotes a take-out mechanism, which is for feeding the hollow dried plate A ′ that has been dried and cut into a predetermined length to the next step, and can be conveyed at a speed higher than the extrusion speed. Numeral 32 is a firing furnace consisting of a roller hearth kiln, which fires the hollow drying plate A'continuously in a short time, the temperature and speed can be easily controlled, and the size is greatly reduced compared to the conventional tunnel dryer. It is a thing. That is, the firing furnace 32 has a mountain-shaped temperature distribution from the inlet 32a to the outlet 32b, and is configured by temporarily dividing the preheating region 33, the firing region 34, and the cooling region 35 in this order, and the temperature of the preheating region 33 is 150 to 700. C., the firing region 34 is 800 to 1300.degree. C., and the cooling region 35 is up to 600 to 100.degree. Of course, depending on the type and composition of clay, the temperature setting between the regions is different, and the temperature between the regions is not clearly classified, but is a temporary classification during continuous firing. Further, the firing furnace 32 will be described. The firing furnace 32 burns a heatable gas, for example, LPG gas to burn the hollow drying plate A ', and the burner (not shown) is arranged in each of the above-mentioned regions. It is provided corresponding to. Further, a mesh belt, a metal roller, a ceramic roller, an alumina roller, or the like is used as a conveying means for the hollow drying plate A'in the firing furnace 32 .
Since the temperature rises up to about 1300 ° C, for example, as shown in FIG. 6, an alumina roller 38 is placed between the metal main shafts 36 and 37 so that the heat conduction is prevented from being transmitted to the drive source. is there. The firing region 34 of the firing furnace 32 forms a furnace with refractory bricks and the like, and passes through it linearly and continuously, and an exhaust damper (not shown) is arranged between each device and region. It is something to set up.

Next, the operation will be described.

First, a clay consisting of Shigaraki clay, chamotte, a water reducing agent and water is prepared as a raw material. The weight% is, for example, Shigaraki clay 61.5%, chamotte 18%, water reducing agent 0.5% (trade name:
Cell Flow, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., water 20% clay mixer (MP
-100 type manufactured by Miyazaki Tekko Co., Ltd.). Also, the extrusion molding machine 1 has a model name MV with an extrusion capacity of 100 to 150 l / hr.
-FM-Al type (Miyazaki Tekko Co., Ltd.) was used. The pump 7 uses a ring blower to connect dry air heated by compression when blown to 20 to 50 ° C. to the connecting pipe 6 exposed to the outside of the base 2 via the hose 8 and another hose 8 (one-dot chain line). ) Is connected to the air inlet / outlet port 20 of the microwave heater 12 . Further, the far-infrared heater device 26 has ten far-infrared heaters 28 arranged every 10 meters to diffuse the water content in the extruded hollow molded article A to the surface to accelerate dehydration and to reduce the water content to 1%.
It can be reduced to the following. Further, the extrusion speed of the extrusion molding machine 1 is 200 mm / min, and the extrusion is performed in the cross section shown in FIG. 3 (a).
And the line distance from the base 2 to the running cup 30 was set to 15 m. Of course, the length of this line is set according to the shape, size, and thickness of the extruded hollow molded body A. Further, the firing furnace 32 is set to have a temperature curve that matches the composition. The pass lines of the extruded hollow molded article A were at the same height, and the moving speed of the conveying section 9 was set so as to be synchronized with the extruding speed. Therefore, the raw material containing clay as the main material is continuously extruded from the extruder 1 onto the conveying section 9 in the cross section shown in FIG. The extruded hollow molded body A that has been extruded is fed to the microwave heating machine 12 at the above-described speed, and while passing through the heated space 19 of the microwave heating machine 12 , the extruded hollow molded body A is heated by the microwave B and air C. A large amount of water vapor generated by microwave heating by the air C sent to the hollow portion a and the outer surface is blown off both inside and outside the hollow portion a at the same time to create an environment in which it is easy to evaporate at the same time, and the occurrence of dew condensation is eliminated. The rigidity of the soft extruded body A is increased to an average in a short time so as to prevent cracks, warpage, deformation, and explosion due to overheating. It is vaporized at a quantile and is fed from the outlet 18 to the far infrared heater device 26 to dry the water content to 1% or less and fed to the traveling cutter 30, and the dried continuous strip-shaped extruded hollow molded body A is predetermined. Cut to length. Then, the extruded hollow molded article A was dried in a short period of about 15 to 30 minutes from extrusion to cutting and as a continuous body.
When the extruded hollow molded article A was simply heated by using the microwave B, it was rapidly heated from the inside for a short time, so that the adverse effects of explosion and dew condensation were severe, and it was not practical. Next, the hollow dry plate A ′ cut to a predetermined length, for example, about 606 to 7272 mm, is fed to the firing furnace 32 through the take-out mechanism 31, preheated → fired → cooled, and the hollow porcelain plate A ″ is supplied from the outlet 32b. Although the firing time varies depending on the thickness, size and length of the hollow drying plate A ', it takes about 30 minutes to 3 hours depending on the feeding and temperature control. In addition, the hollow ceramic plate A ″ manufactured by this apparatus had a predetermined length without cracks, warps, twists, or explosions.

The above description is merely one example of the apparatus according to the above, and a glaze machine is provided between the traveling cutter and the firing furnace, or a microwave heating machine 12 as shown by a chain double-dashed line in FIG. In combination with the pump 7, or independently providing an air supply device instead of the pump 7, or by supplying warm air or hot air to the far-infrared heater device 26 from the firing furnace 32 as shown by the one-dot chain line, for further drying. It can also be configured to save time. Of course, it is possible to supply one or more kinds of hot air, hot air, etc. to the microwave heater 12 not shown.

〔The invention's effect〕

As described above, according to the apparatus for continuously producing a hollow porcelain plate according to the present invention, extrusion of clay, reduction of water content, drying, firing,
There is a great feature that cooling can be performed in a straight line in a short time and at a high speed as a continuous zone. Further, in the present invention, a hollow extruded body containing water in an amount of 22 to 15% (weight ratio) is heated in two stages and air or the like is blown to the hollow portion of the extruded hollow body, the exposed surface or the heated space. As a result, a large amount of water vapor, dew condensation water, etc. generated during heating are excluded from the inside and outside of the extruded hollow molded body and the atmosphere to create an environment that is easier to dry. It has the characteristic that it can be dried quickly by the body. In addition, productivity is 10% compared to Spypid which took several days before.
It is characterized in that it can be dried in -60 minutes, and then the continuous body can be cut into a predetermined length, and this can be baked in about 30 minutes to 3 hours. Furthermore, the volume of the extruded hollow molded article shrinks by 10% or more when dried, as compared with during extrusion, but there is an advantage that the adverse effect on the extruded hollow molded article can be absorbed by a flea roller or the like. Further, in the present invention, since extrusion to drying are arranged in series, there is a feature that a long body and a continuous body can be dried quickly.

[Brief description of drawings]

1 (a) and 1 (b) are schematic configuration diagrams showing an embodiment of an apparatus for continuously producing hollow porcelain plates according to the present invention and a sectional view taken along the line ii, and FIG. 2 (a) is an outlet of an extruder. Explanatory diagram showing a part,
(B) is an explanatory view showing cores extracted, and FIG.
(N) is a cross-sectional view showing an example of an extruded hollow molded body, FIGS. 4 (a), (b), and 5 are explanatory views showing the main constituent members of the fli-roller conveying section of the microwave heater, and FIG. FIG. 3 is an explanatory diagram showing an example of a firing furnace. 1 ... Extruder, 3 ... Core, 7 ... Pump, 9 ...
Conveyor, 12 …… Microwave heater, 26 …… Far infrared heater device, 30 …… Cutter, 32 …… Baking furnace.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication C04B 33/30 L 33/32 L

Claims (1)

[Claims] 1. An extrusion molding machine with a core for continuously extruding a raw material mainly made of clay in a predetermined shape having a hollow portion and an extrusion hollow molding body continuously extruded from the extrusion molding machine A conveying section for transferring to the process, an oven continuous microwave heater for reducing the water content of the extruded hollow molded body sent from the conveying section in a short time, and an extruded hollow molded body passing through the microwave heating machine. A far-infrared heater device for reducing water content and increasing temperature, a running cutter for cutting a continuous extruded hollow molded body in a dry state to a fixed length sent from the heater device, and a constant length cut by the cutter A take-out mechanism for conveying the hollow dry plate and a baking furnace for baking the hollow dry plate continuously in a short time are arranged, and gas is extruded from the outside into a core installed in the die of the extruder. In the hollow part of the hollow molded body A pump for feeding without hindrance and an air inlet / outlet for supplying air or the like to the inner wall of the heated space other than the inlet / outlet of the microwave heater, or for discharging water vapor and air in the space are provided. Characteristic hollow porcelain plate continuous production equipment.