JPS62117703A - Rotary molding equipment for slip cast utilizing centrifugalforce - 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 slip casting mold device for obtaining a molded body by casting a slurry containing powder of ceramic, metal, carbon, etc. In particular, the present invention relates to a rotary molding device for slip casting that performs molding using centrifugal force.

[Conventional technology]

The so-called slip casting method, in which a slurry of ceramic or metal powder is cast into a mold to obtain a molded body, is widely used.

Among these methods, the casting method using centrifugal force is a convenient method for obtaining molded objects such as sleeves.

In the case of centrifugal casting, gypsum is often used as the mold material. However, this mold material has low strength, so it is usually held in a highly rigid frame to prevent it from breaking during rotation. For this reason, in the past, a cylindrical mold was fixedly held within a rotating frame, and the rotating frame was placed on rollers and rotated. Such a conventional rotary molding apparatus is shown in FIG. 2 is a cylindrical mold, 2 is a rotating frame, 3 is a roller, 4 is a mold end cover, 5 is a frame end cover, and 6 is a hopper for pouring slurry.

[Problem that the invention seeks to solve]

In a rotary molding apparatus having such a structure, since the cylindrical mold 1 is installed in the rotary frame 2, a certain amount of clearance 7 is required between the two.

This is because without the clearance 7, the cylindrical mold 1
This is because it is practically impossible to attach and detach the mold 1 and the rotary frame 2, and since there are tolerances in the mold 1 and the rotating frame 2, a margin for this is required. The cylindrical mold 1, which is held with a slight clearance 7, is rotated at the number of revolutions required for centrifugal casting (50
When the mold 1 is rotated at a speed of 0 to 4000 rpm), vibrations occur in the mold 1, which causes defects such as segregation and cracks in the powder slurry molded body.

Further, after the slurry is cast, the molded body must be released quietly and smoothly, so the cylindrical mold 1 has a structure in which it is divided into two parts in the axial direction.

Therefore, there is a gap 7 between the cylindrical mold 1 and the rotating frame 2.
If so, when the cylindrical mold 1 is fixed in the rotating frame 2, a gap will be created between the dividing surfaces 8, 8 of the cylindrical mold 1, and the gap will become larger due to rotation.

Therefore, if a slurry such as ceramics is cast in this state,
Sludge enters these gaps, causing defects such as cracks in the molded product.

Accordingly, an object of the present invention is to provide a rotary molding apparatus utilizing centrifugal force that does not have the above-mentioned problems.

[Means for solving problems]

The rotary molding device for slip casting of the present invention molds powder slurry while applying centrifugal force, which has a dual structure of a rotary mold having a molding space and a rotary frame that receives the rotary mold. The rotary mold and the rotary frame are integrally formed, and opposing surfaces of the rotary mold and the rotary frame are tapered in a complementary manner, so that the rotary mold can be fixed to the rotary frame from the axial direction.

[For production]

In the molding device of the present invention, the opposing surfaces of the rotary mold and the rotating frame are tapered in a complementary manner, which means that the outer surface of the rotary mold and the inner surface of the rotating frame are at the same inclination but in opposite directions. It means tapered. With this structure, when the rotary mold is inserted into the rotary frame in the axial direction, the rotary mold is completely fixed to the inner surface of the rotary frame, and there is no need to provide a clearance for attachment and detachment. Furthermore, even if there are slight molding errors between the opposing surfaces of the rotary mold and the frame, perfect fixation is ensured by slightly adjusting the axial position of the rotary mold.

〔Example〕

The present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a rotary molding apparatus according to an embodiment of the present invention.

In this figure, members corresponding to those in FIG. 4 are given the same numbers. It has a molding space 9 inside and an outer surface 1a.
A rotary mold 1 having a tapered shape is fixed within a rotary frame 2 having a tapered inner surface 2a. Since the outer surface 1a and the inner surface 2a have the same taper angle in opposite directions, they can be completely fixed by pushing the rotary mold 1 in the axial direction. Mold end covers 4a and 4b are provided at both ends of the rotary mold 10. End cover 4
A has a central hole from which an injection pipe of a casting hopper 6, which will be described later, protrudes. On the other hand, the end force bar 4b is constructed to completely seal the large diameter end of the rotary mold. End cover 4a.

A frame end cover 5a is provided on the outside of each frame end cover 4b.

5b is placed. The frame end cover 5a fixes the end cover 4a in the axial direction and has a hopper hole in the center. Further, the frame end cover 5b has a protrusion that can enter into the rotating frame 2 so as to push the end cover 4b. frame end cover 5a,
5b is fixed to the rotating frame 2 by appropriate means. The injection pipe of the slurry casting hopper 6 passes through holes in the end covers 5a, 4a and opens into the molding space 9. Finally, the rotating frame 2 is placed on the rollers 3, and the rotation of the rollers 3 causes the entire rotary molding apparatus to rotate.

When performing slip casting using the apparatus of the present invention, after the apparatus is assembled as shown in FIG. 1, slurry is injected from the hopper 6, and the slurry is uniformly adhered to the inner surface of the rotary mold 1 and solidified. Thereafter, the frame end cover 5b is attached and detached, the mold end cover 4b is removed, and the rotary mold 1 is taken out. Since the outer surface 1a of the rotary mold 1 is tapered toward the tip, removal is extremely easy.

FIG. 2 is a sectional view taken along the line AA in FIG. 1, and shows that the rotary mold 1 and the rotary frame 2 are in close contact with each other.

FIG. 3 shows another embodiment of the device of the invention. This device basically has the same structure as in FIG. 1, but has a partial recess 10 in the inner surface 2a of the rotary frame 2. This recess 1
0 may have any shape as long as the rotary mold 1 does not rattle in the rotary frame 2. This recess 10 makes it easier to attach and detach the rotary mold. Note that the recess may be provided on the outer surface 1a of the rotary mold 1, or may be provided on both the inner surface 2a and the outer surface 1a.

The monolithic rotary mold 1 can be manufactured as shown in FIG. A metal core 12 is installed at the center of a metal pedestal 11, and a conical outer frame 14 is installed at an outer edge section 13 of the pedestal 11. Next, a slurry of the rotary mold material is poured into the space formed by the base 11, the cores 1 and 2, and the outer frame 14, and is dried and solidified.

Thereafter, the outer frame 14 and core 12 are removed to obtain a rotary molded product. Note that the outer frame 14 can be made into a two-piece structure to facilitate removal of the molded product inside.

The apparatus of the present invention can be used for slip casting of any powder such as ceramic powder, metal powder, carbon powder. Additionally, the rotary mold can be made of any material, but gypsum is suitable.

In the rotary molding apparatus shown in Figure 1, the inner diameter of the mold 1 is set to 8
0mm, using ceramic slurry, 200-150
Slip cast molding using centrifugal force was performed at a rotation speed of 0 rpm. The obtained tubular molded product had a uniform wall thickness, and there were no defects such as steps or cracks on the surface.

〔Effect of the invention〕

Since the rotary molding apparatus of the present invention has the above-described structure, it has the following effects.

(1) Since the facing surfaces of the rotary mold and the rotary frame are tapered in a complementary manner, when the rotary mold is installed, it can be completely fixed without any clearance between the two. This can eliminate vibrations caused by the gap between the rotary mold and the rotary frame, and can prevent defects such as segregation and cracking of ceramic products caused by vibrations.

(2) Since the rotary mold is integrally formed, it is possible to prevent the occurrence of cracks, steps, etc. in the resulting molded product, and also prevent defects such as cracks caused by these.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a rotary molding apparatus according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line A-A in FIG. 1, and FIG. FIG. 4 is a longitudinal sectional view of a rotary mold manufacturing apparatus, and FIG. 5 is a longitudinal sectional view of a conventional rotary mold apparatus. DESCRIPTION OF SYMBOLS 1... Rotating mold, 2... Rotating frame, 3... Roller, 4a, 4b... End cover, 5a, 5b...
・Frame end cover, 6...Casting hopper. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (3)

[Claims] (1) A rotary mold device for slip casting that molds powder slurry while applying centrifugal force, which has a dual structure of a rotary mold having a molding space and a rotary frame that receives the rotary mold, and The mold is integrally formed, and opposing surfaces of the rotary mold and the rotary frame are tapered in a complementary manner, so that the rotary mold can be fixed in the rotary frame from the axial direction. Features of rotary molding equipment for slip casting. (2) The rotary mold device for slip casting according to claim 1, wherein the rotary mold is elongated so as to be able to mold a long sleeve. (3) In the rotary molding device for slip casting according to claim 1 or 2, at least one of the opposed surfaces of the rotary mold and the rotary frame is partially provided with a recess. Features of rotary molding equipment for slip casting.