JPS6054162B2 - Method for manufacturing large ceramic containers - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a method for manufacturing large ceramic containers that cannot be carried by human hands, and in particular, uses a horizontally split three-tiered plaster mold to produce large ceramic containers that have previously been considered impossible. The present invention relates to a method for manufacturing large ceramic containers using plaster molds, which makes it easy to manufacture pots, bottles, etc.

The pour molding method, which takes advantage of the water absorption properties of plaster molds, is generally known, but conventional plaster molds were intended for relatively small pottery such as tea bowls and vases, and were so large that they could not be carried by humans. Until now, it has been considered impossible to manufacture large containers using the casting method using plaster molds.

In other words, molded products made using the pour molding method have a higher moisture content than molded products made using other methods, and require sufficient time and care to dry them. However, when the molded product becomes too large to be carried by human hands, the bottom of the molded product is pressed down by its own weight, which prevents drying and shrinkage more than other parts, resulting in completely unmanageable parts. Fatal thin cracks formed at the bottom, reducing the commercial value, and for this reason, it had been considered almost impossible to manufacture large ceramic containers using the plaster casting method. As a result of repeated trial production and research in order to solve the above-mentioned manufacturing difficulties, the present invention uses a horizontally divided three-stage plaster mold, in which the middle mold is suspended upward together with the molded product. By making it possible to remove the mold from the lower mold, promoting drying of the bottom of the molded product, and preventing cracks from forming at the bottom, it is possible to make large ceramics using a plaster mold, which was previously considered impossible. The container was successfully manufactured.

To describe the present invention in detail, there is a method for manufacturing a large ceramic container with a narrow mouth and a swollen body, such as a pot or bottle, using a plaster mold. Divided into three tiers, the lower tier type has a bottom, the middle tier type has a large diameter at the top and an annular groove carved on the outer periphery, and the upper part forming the top surface of the large container is open. The upper type and the lower type,
After assembling the middle mold and the upper mold one after another, pour the slurry through the opening of the upper mold and leave it for an appropriate amount of time. After forming a layer of base soil to a predetermined thickness on the inner wall surface of the plaster mold,
After the remaining slurry inside the plaster mold is discharged and the molding base soil has hardened to some extent, the upper mold is pulled out upward, and then the middle mold is pulled out together with the molding base soil itself upward from the lower mold. , while drying in this state, the molded base soil body with the middle mold still attached is placed on the top of the rootstock, the middle mold is lowered under the rootstock and removed from the molded base soil body, This is a method for producing a large pottery container, which is characterized by heat-treating the thus-obtained molded base body in a conventional manner.

Hereinafter, a specific configuration of the present invention will be explained in detail based on illustrated embodiments.

The method for producing a large pottery container of the present invention relates to a method for producing a large pottery container, such as a pot or bottle, with a narrow mouth and a rounded body using a plaster mold. , divide the plaster mold horizontally into three stages, bottomed bottom mold 1,
A middle type 2 whose upper part has the maximum diameter of the body of the large container and an annular groove carved on the outer periphery, and an upper type 3 whose upper part, which forms the upper surface of the large container, is an opening. After assembling the lower mold 1, middle mold 2, and upper mold 3 in sequence, pour a suitably mixed slurry into the opening 4 of the upper mold 3, leave it for an appropriate period of time, and then clean the inner wall surface 5 of the plaster mold. After confirming that the base soil layer 6 has been formed to a predetermined thickness, excess slurry 12 inside the plaster mold is discharged out of the plaster mold using a pump or the like, and as it dries, the molded base material is After the soil 7 has solidified to some extent, the upper mold 3 is pulled out upward using a chain block placed on the ceiling of the workshop, etc., and then removed at an appropriate time. After drying for a while and waiting for the molding base soil body 7 to harden, the middle mold 2 is lifted upward together with the molding base soil body 7 and removed from the lower mold 1, and while drying in this state, the middle mold The molding base body 7 is placed on the top surface of the rootstock 8 with the mold 2 still attached, and the middle mold 2 is lowered under the rootstock 8 and removed from the molding base body 7. The molded base body 7 thus obtained is heat-treated by a conventional method.

FIG. 1 shows a state in which a lower mold 1, a middle mold 2, and an upper mold 3 are assembled.

Although the illustrated embodiment is divided into three stages, it goes without saying that all or part of each of the stage molds 1, 2, and 3 may be further divided laterally to form a multi-stage mold. The lower mold 1 has a bottom and forms the bottom of a large container to be molded, and the middle mold 2 forms the body of the large container. In addition, the upper part of the middle mold 2, especially the vicinity of the fitting part with the lower part of the upper mold 3, is formed to have the maximum diameter of the body of the large container to be molded so that demolding can be easily performed. The lower part of the middle mold 2 has a smaller diameter than the upper part.
In addition, on the contact surfaces of each stage mold 1, 2, and 3, there are
As shown in the figure, a pair of protrusions 9 and recesses 10 are formed so that they can be fitted together and the plaster mold will not shift when assembled. Figure 4 shows the state in which slurry is injected into the assembled plaster mold from the opening 4 of the upper mold 3.The slurry 12 absorbs moisture over time and forms on the surface of the plaster mold. Layer 6 with low moisture in the contact area
is formed, and when this layer 6 reaches a predetermined thickness, the remaining slurry 12 inside the mold is drained out of the mold, and if left for a while, the plaster mold will still absorb moisture from the molding base 7, so eventually It will shrink and release from the mold. Therefore, the upper mold 3 is lifted upward to be demolded, but since the upper mold 3 has a large diameter at the bottom and a small diameter at the top, it can be demolded more easily than the molding base body 7. . FIG. 5 shows a state in which the upper mold 3 is removed and the upper surface of the molded base soil body 7 is exposed. In this state, the molded base soil body 7 is further dried.
Once solidified, the molded base material body 7 is lifted upward together with the middle mold 2 using a chain block or the like installed on the ceiling of the workshop.

As described above, since the upper part of the middle mold 2 has a larger diameter than the lower part, the middle mold 2 can be easily pulled up while holding the molded base body 7. By this operation, the lower mold 1 can be separated from the molding base body 7. In addition, an annular groove 11 is provided on the outer periphery of the middle mold 2.
is engraved on it, and a band or the like is fitted here to serve as a handhold when hoisting with a chain hoist or the like. Due to this lifting, the bottom of the molded product is exposed to the air and drying is accelerated. Figure 6 shows the state in which the molding base body 7 is placed on the upper surface of the rootstock 8 with the middle mold 2 attached. It can be placed under the legs and completely removed from the mold.

Next, the demolded molded base body 7 is fired in a conventional manner to obtain a large pottery container.

The method of the present invention has the above-mentioned structure, and it has become possible to easily manufacture large ceramic pots, bottles, etc., without difficult work, which was considered impossible by conventional casting methods. In particular, the upper part of the middle part of the three-tiered part has a larger diameter than the lower part, and an annular groove is provided on the outer periphery, so you can wrap a belt, etc. It is possible to remove the mold from the lower mold that covers the bottom of the molded base soil by lifting it together with the molded base soil body, and to expose the bottom of the molded base soil body to air to promote drying. It has become possible to prevent cracks from forming at the bottom of the base soil body. In addition, the parting line that occurs at the joint of the molds is formed in the horizontal direction, giving it the same texture as using a potter's wheel, and it also has the advantage of requiring almost no post-processing. be.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of the assembled plaster mold, Figure 2 is a bottom view of the upper mold, Figure 3 is a plan view of the middle mold, and Figure 4 is a cross-sectional view of the plaster mold with slurry poured into it. , FIG. 5 is a sectional view with the upper mold removed, and FIG. 6 is a front view showing the middle mold removed. 1: Lower mold, 2: Middle mold, 3: Upper mold, 4: Opening, 5
: Inner wall surface, 6: Layer, 7: Molded base soil body, 8: Rootstock, 9
: convex part, 10: concave part, 11: concave groove, 12: slurry.

Claims (1)

[Claims] 1. A method of manufacturing a large ceramic container with a narrow mouth and a swollen body, such as a vase or bottle, using a plaster mold, in which the plaster mold is divided horizontally into three stages, bottomed bottom type,
The middle type has a large diameter at the top and has an annular groove carved on the outer periphery, and the upper type has an opening at the top that forms the upper surface of the large container. After assembling the molds one after another, pour the slurry through the opening of the upper mold and leave it for an appropriate amount of time. After a layer of base soil is formed to a predetermined thickness on the inner wall of the plaster mold, the remaining inside of the plaster mold is drained. After draining the slurry and allowing the molding base soil to harden to some extent, pull out the upper mold upward, then pull out the middle mold together with the molding base soil upward and remove it from the lower mold, leaving it as it is. While drying, the molded base soil with the middle mold still attached is placed on the top of the rootstock, the middle mold is lowered under the rootstock, and the mold is removed from the molded base soil, thus obtained. A method for producing a large pottery container characterized by heat-treating the molded base material body by a conventional method.