JPH0453704A - Gypsum mold for casting ceramics slurry - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a plaster mold for ceramic slurry casting for producing ceramics.

[Conventional technology]

Ceramics are manufactured by casting ceramic slurry into the cavity of a plaster mold that has water absorption ability, and firing the resulting molded body.

FIG. 2 is a cross-sectional view of a fired ceramic body used as a daily-bore bottle. When molding the molded body for manufacturing the fired ceramic body (1) that will become the vase using the slurry molding method, a pair (two pieces) of lower molds (2a) and upper molds as shown in Fig. 3 are used. A plaster mold consisting of (2b) (
2) and a method of using a plaster mold (3) consisting of one mold as shown in FIG.

In Figure 3, the plaster mold (2) has a concave mold surface (4a) formed on the lower mold (2a) and a convex mold surface (4b) formed on the upper mold (2b). A cavity (5) is formed, and a valve (
The slurry (8) is injected through 7a) and (7b).

The method for spinning the slurry (8) when using the plaster mold (2) in Fig. 3 is as follows: First, the valves of the tanks (6a) and (6b) (
7a) and (7b) and open the cavity of 1 plaster mold (2) (
Filling the slurry (8) in 5) As time elapses, the water in the slurry (8) is absorbed from the mold surfaces (4a) and (4b),
The slurry (8) injected into the plaster mold (2) covers both mold surfaces (4).
After completing the first inking on a) and (4b), the tank (6
Close the valves (7a) and (7b) in a) and (6b), remove the upper mold (2b), invert the lower mold (2a), and take out the molded body (9).

In Figure 4, the plaster mold (3) is the lower mold (2a) in Figure 3.
Consists of one type corresponding to . The method for casting the slurry (8) when using the plaster mold (3) in Figure 4 is as follows:
) Pour the slurry (8) from the tank (6) into the cavity (5) of the plaster mold ( ) to the desired thickness.
3), the excess slurry (8) is discharged, and then the plaster mold (3) is turned over and the molded body (9) is taken out.

The molded body (9) thus taken out is fired to produce a fired ceramic body (vase).

[Problem to be solved by the invention]

However, in the conventional plaster mold as mentioned above, the third
When using the plaster mold (2) shown in the figure, the slurry (8) should be applied to the mold surface (
4a) and (4b) to be uniformly inked over time,
An unfilled void portion (11) is formed in the thick wall portion (10) of the cavity (5).

In addition, when using the plaster mold (3) in Fig. 4, the molded body (9
) is not uniform in thickness, resulting in unevenness, and the slurry (8) used must be made in excess to cover the amount to be discharged, resulting in problems such as wastage.

This invention was made to solve the above-mentioned problems, and allows the slurry to completely adhere to the parts of the cavity with different thicknesses, and to form a molded body that is uniform and has no irregularities, making it easy to use. The purpose of the present invention is to obtain a plaster mold for ceramic slurry casting which requires only the amount of slurry corresponding to the molded body.

(Means for Solving Problem 11) A plaster mold according to the present invention is a plaster mold used for casting ceramic slurry, in which one mold surface forming a cavity has water absorption ability, and the other mold surface has water absorption ability. It has no power.

That is, in this invention, one mold surface of the plaster mold to which the slurry is attached has water absorption ability, and the slurry is attached by water absorption.

The other mold surface should be made of a non-water-absorbing material (e.g. stainless steel, plastic, etc.), or a non-water-permeable, especially hydrophobic tape, etc. should be attached to the surface of the plaster mold, so that it has no water-absorbing ability. Structure.

[For production]

In the plaster mold of this invention, the slurry adheres only to the mold surface that has water absorption ability using plaster, but the slurry does not adhere to the mold surface that does not have water absorption ability, so the thickening of the thick part is completed. Until this is done, the inking of other parts is not completed. Therefore, the slurry is completely inked even in the thick parts, no voids are formed, and a uniform molded article with no irregularities is obtained.

[Embodiments of the invention]

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

FIG. 1 is a cross-sectional view showing the plaster mold of the example. In the figure, the same parts as in FIG. 3 are given the same reference numerals and the explanation is omitted. The structure is similar, and the lower mold (2a) is made of gypsum, and its mold surface (4a) has water absorption ability, but the mold surface (4b) of the upper mold (2b) has water absorption ability. I don't have it.

Such an upper mold (2b) is made of a non-water-absorbing material such as stainless steel or plastic, or if it is made of a water-absorbing material such as plaster, the mold surface (
It is formed by attaching a water-impermeable film, tape, etc. to 4b). In Figure 1, the mold surface (
4b) is illustrated with a dashed line.

The method for casting slurry (8) using the plaster mold (2) described above is as follows: First, as shown in Figure 1, the lower mold (2a) to which the slurry (8) adheres and the slurry (8) to which it does not adhere. Combine the upper mold (2b). and a tank (6a) containing slurry (8), (
6b), open the valves (7a) and (7b), and remove the plaster mold (2).
) Inject the slurry (8) into the cavity (5). As time passes, the slurry (8) spreads to the mold surface (4a) of the lower mold (2a).
The mold surface (4b) of the upper mold (2b) is not inked at all.

Therefore, until the thick part (10) is finished, the other parts are not finished, and therefore the thick part (10) is coated with slurry (8).
When the slurry (8) is completely deposited and no voids (11) are formed, the upper mold (2b) is removed and the lower mold (2a) is inverted and molded. Take out the body (9).

In addition, although the example of the lower mold (2a) and the upper mold (2b) was explained in the above-mentioned example, 1. Both may be reversed or may be in other directions, and the direction is not important. It is applicable not only to vases but also to other fired ceramic bodies.

〔Effect of the invention〕

As described above, according to the present invention, one mold surface of the plaster mold has water absorbing ability and the other mold surface does not have water absorbing ability, so that voids are formed due to mud coming from the mold. It is possible to obtain a uniform molded body without any irregularities, and also to produce a fired ceramic body at low cost without any excess slurry being discarded.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a plaster mold according to an embodiment, FIG. 2 is a cross-sectional view of a fired ceramic body, and FIGS. 3 and 4 are cross-sectional views of a conventional plaster mold. In each figure, the same reference numerals indicate the same or corresponding parts, (1)
(2), (3) are plaster molds, (2) are ceramic fired bodies, (2) and (3) are plaster molds, (2)
a) is the lower mold, (2b) is the upper mold, (4a), (4b) is the mold surface, (5) is the cavity, (6), (6a), (6b)
is a tank, and (8) is a slurry.

Claims (1)

[Claims] (1) A plaster mold for casting ceramic slurry, which is characterized in that one mold surface forming a cavity has water absorption ability and the other mold surface does not have water absorption ability in a plaster mold used for casting ceramic slurry. .