JP2727448B2 - Drying equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a drying apparatus for drying an ultra-thin sheet-shaped ceramic molded body extruded to a thickness of 0.5 mm or less. (Prior Art) In order to manufacture a sheet-like molded body made of a ceramic material having a thickness of 0.5 mm or less, a method such as a doctor blade method or a roll coating method called a reverse roll coater is widely used. Have been. These methods, which are also called a tape casting method, are methods in which a slurry (slurry) containing a ceramic material is applied on a plastic film, dried, and then the sheet-like molded body is peeled from the plastic film. . In this method, a large amount of an advantageous solvent must be used to prepare a slurry containing a ceramic material, so that the working environment is deteriorated and there is a risk of an explosion accident due to vapor of an organic solvent. In addition, the plastic film can be used repeatedly only about several times, and the use of an organic solvent causes a problem that the production cost of the sheet-shaped molded article increases. In recent years, with the progress of ceramic material extrusion molding machines and organic binders, thickness 0.5 mm
Extrusion molding of the following ultra-thin sheet-like molded articles has become possible. In this method, a plastic comprising a ceramic material, an organic binder, and water is extruded from an extrusion die 1 of an extruder to form a sheet-shaped molded body 2, and the sheet-shaped molded body 2 is transferred to a belt conveyor 3. Since it is placed and dried in the drying tunnel 4 (see FIG. 2), the above-described problem does not occur. (Problems to be Solved by the Invention) By the way, in the extrusion molding, the drying tunnel 4 cannot be made too long despite the fact that water, which hardly evaporates as compared with the organic solvent, must be evaporated. ° C
The temperature rises to ~ 200 ° C. For this reason, it is necessary to use a heat-resistant cotton belt capable of withstanding this temperature for the belt of the belt conveyor 3, but since the surface of the heat-resistant cotton belt is rough and uneven, a very soft sheet-like molded as-extruded form is formed. When the body 2 is placed on a heat-resistant cotton belt, the surface of the sheet-like molded body 2 is scratched or has unnecessary irregularities, so that a smooth surface cannot be obtained unlike the tape casting method.
There was a problem that the bending strength of the baked product was reduced. The present invention has been made in order to solve this problem, and to provide a drying device that can dry an extruded sheet-shaped molded body without giving a surface a scratch or unnecessary unevenness. It is an object. (Means for Solving the Problems) According to the present invention, a gas is blown onto a lower surface of an extruded sheet-shaped ceramic molded body from a number of holes provided in a blast plate at a pressure balanced with the weight of the ceramic molded body. A first drying unit for solidifying the lower surface of the ceramic molded body to some extent while the ceramic molded body is floated flat, and a ceramic molded body with the lower surface dried by the first drying unit facing downward is placed on the heat-resistant wire belt. And a second drying means for drying the whole of the ceramic molded body by transporting the ceramic molded body in the drying tunnel. (Operation) According to the present invention, in the first drying means, a pressure balanced with the weight of the sheet-shaped ceramic formed body is formed on the lower surface of the extruded sheet-shaped ceramic formed body through a plurality of holes provided in the blast plate. The sheet-like ceramic molded body does not meander, wavy, or deform by blowing a gas to lift the sheet-like ceramic molded body flat, so that the sheet-like ceramic molded body is dried by the second drying means. Can be placed flat on the heat-resistant cotton belt, and it is possible to prevent the surface of the sheet-shaped ceramic molded body from being scratched and unnecessary irregularities from occurring. In the first drying means, the lower surface of the sheet-shaped ceramic molded body is dried or thermally gelled and solidified to some extent while the sheet-shaped ceramic molded body is floated up flat, so that the sheet is formed in the second drying means. The shape of the ceramic molded body can prevent the contact surface with the heat-resistant cotton belt from causing scratches and unnecessary irregularities. Furthermore, by drying the sheet-like ceramic molded body using the first drying means and the second drying means, the bending strength of the fired ceramic molded body can be increased. (Embodiment) FIG. 1 shows a configuration of an embodiment of the present invention.
The same reference numerals as those in the drawings indicate the same parts,
Reference numeral 5 denotes a blast plate provided with a large number of fine holes (not shown) for blowing out gas, and the blast plate 5 is a sheet-like molded product 2 between the extrusion die 1 and the belt conveyor 3.
It is installed under the transport path of. In the present embodiment configured as described above, the sheet-like molded body 2 extruded from the extrusion molding die 1 is guided onto the blast plate 5 which blows out gas from the fine holes, and the blast plate 5
The sheet is conveyed to the belt conveyor 3 while floating, while the lower surface of the sheet-like molded body 2 is dried or thermally gelled and hardened. Then, the sheet-like molded body 2 whose lower surface is appropriately hardened is placed on a belt conveyor 3, and
It is sent to the drying tunnel 4 and further dried. By the way, the amount of gas blown out from the blast plate 5 is such that the force of the gas supporting the sheet-shaped molded body 2 and the weight of the sheet-shaped molded body 2 are balanced, and the sheet-shaped molded body 2 is flattened as shown in FIG. However, if the force received from the blown gas exceeds the weight of the sheet-like molded body 2 too much, the sheet-like molded body 2 meanders or undulates, causing Therefore, it is better to suppress the blowing amount to such an extent that the sheet-shaped molded body 2 does not contact the blast plate 5 because the sheet-shaped molded body 2 is deformed. The number of pores provided in the fumarolic plate 5 should be as large as possible, and the number should be 10 or more per square centimeter. In addition, a comparison between a sheet-shaped molded body 2 containing barium titanate as a main component, which was dried and fired by the drying apparatus of the present invention, and a sheet which was dried and fired by the conventional drying apparatus, shows the following table. become that way. (Effects of the Invention) As described above, according to the present invention, in the first drying unit, the sheet-like ceramic formed body is formed on the lower surface of the extruded sheet-shaped ceramic molded body by using a large number of holes provided in the blowing plate. Gas is blown at a pressure commensurate with the weight of the ceramic molded body, so that the sheet-shaped ceramic molded body is lifted up flat, so that the meandering, waving and deformation of the sheet-shaped ceramic molded body are not generated, and the sheet-shaped ceramic molded body is not generated. Since the molded article can be placed flat on the heat-resistant cotton belt of the second drying means, it is possible to prevent the surface of the sheet-shaped ceramic molded article from being damaged and unnecessary irregularities from being generated. . In the first drying means, the lower surface of the sheet-shaped ceramic molded body is dried or thermally gelled and solidified to some extent while the sheet-shaped ceramic molded body is lifted up flat, so that the sheet is formed in the second drying means. This has the effect of preventing the ceramic shaped body in the form of a scratch and unnecessary irregularities from being generated on the contact surface with the heat-resistant cotton belt, and increasing the bending strength of the fired ceramic shaped body.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration diagram of one embodiment of the present invention, and FIG. 2 is a configuration diagram of a conventional drying device. DESCRIPTION OF SYMBOLS 1 ... Extrusion metal mold, 2 ... Sheet-shaped molded object, 3 ... Belt conveyor, 4 ... Tunnel for drying, 5 ... Foam plate.

Claims (1)

(57) [Claims] On the lower surface of the extruded sheet-shaped ceramic molded body, a gas is blown from a large number of holes provided in a blast plate at a pressure proportional to the weight of the ceramic molded body, and while the ceramic molded body is floated up flat, First drying means for solidifying the lower surface of the ceramic molded body to a certain extent; and placing the ceramic molded body having the lower surface dried by the first drying means facing downward on a heat-resistant belt, and transporting the ceramic molded body in a drying tunnel. A drying device for drying the entirety of the ceramic molded body.