JP2504797Y2 - Casting mold for ceramic products with overhang - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a molding die for cast molding of ceramics, and more particularly to a molding die for molding a product having an inverse taper.

(Prior Art) Conventionally, a gypsum mold has been used for cast molding of ceramics.

However, when a product having an inverse taper, for example, a drum-shaped cup and the like is formed by cast molding, the mold cannot be removed, and therefore the mold must be broken and removed.

Therefore, it is conceivable to use a split mold, but in the split mold of the gypsum type, scratches on the mold appear at the seams of the mold.

That is, the viscous fine particles are composed of scale-like, flake-like, etc. crystals, and tend to be arranged parallel to the surface at the corners of the mold, and because the firing shrinkage in the thickness direction is larger than that direction, before firing Even if it is finished smooth, it rises after firing and appears as scratches on the mold.

Therefore, in the case of a drum-shaped cup, etc., the upper part and the lower part are separately rotomolded, and raw bonding is performed, which is time-consuming and costly.

(Problems to be solved by the invention) The present invention has been made in view of the present situation, and the purpose thereof is to cast a ceramic product having an inverse taper without using a split mold and break the mold. An object of the present invention is to provide a molding die for cast molding which can be die-cut without any die.

(Means for Solving the Problem) In order to achieve the above-mentioned object, the casting mold of the present invention comprises a mold for molding the surface side having an overhang portion made of an elastic material, and The mold which is in charge of molding on the surface side other than the surface that is formed is made of a non-stretchable and water-absorbing material, and the elastic material mold is backed up from the back mold to prevent deformation of the mold during molding. A backup member that can be divided is provided.

(Operation) The casting mold for molding which is configured as described above can be removed even if there is an overhang by stretching the mold made of a stretchable material, and unlike the split mold, there is no seam of the mold. , Does not cause mold scratches.

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

In this embodiment, as a ceramic product having an overhang, there is provided an instrument portion whose diameter gradually decreases from an opening to a bottom, and a base leg which extends further downward from the bottom of the instrument portion and gradually increases the diameter downward. Shows a forming die for casting and forming a drum-shaped cup made of a part, and the forming die is composed of an inner die B and an outer die A each having a casting space 3 corresponding to a drum-shaped cup which is a product in a die assembled state. Further, the inner mold B is composed of an upper mold B ₁ for forming the inner surface shape on the cup side and a lower mold B ₂ for forming the inner surface shape on the cupboard leg side.

The inner mold B is made of a water-absorbing material such as gypsum. The inner mold B is provided with a casting port 1 for sludge and an air blowing hole 2 for releasing the mold.

On the other hand, the outer mold A is in charge of molding the shape of the entire outer peripheral surface having a drum-shaped cup overhang, and is made of a stretchable material, for example, silicon rubber, and corresponds to the outer surface shape of the cup. It is shaped like a drum.

The outer mold A made of the elastic material is backed up on the back side by the backup member C in the mold assembled state.

The backup member C prevents the outer mold A from being deformed due to casting, and is formed in a ring shape surrounding the outer mold A with a material having a certain degree of rigidity, such as gypsum.
The inner peripheral surface corresponds to the outer surface of the outer mold A.

The backup member C is configured to be divided into a plurality of pieces.

Then, such a molding die is assembled into a mold, and the slurry is cast into the casting space 3 from the slurry casting port 1 according to a conventional method. At this time, the inner mold B made of gypsum absorbs the water content of the slurry to some extent, and the slurry becomes a semi-hardened molding base a whose surface is dry. However, the molding base a is easily separated from the inner mold A, but air is blown into the air blowing hole 2 and air is blown between the mold surface and the molding base a through the fine holes of the inner mold B made of gypsum. Is supplied to further improve the mold release of the molding base.

In addition, the molding die is opened after the molding material has hardened to some extent, the backup member C is divided and removed, and the molding material a is removed from the molding die. It is stretched outward and removed from the molding base a.

(Effect) Since the present invention is configured as described above, it has the following effects.

Since the mold responsible for molding the surface with overhang of the product was formed of elastic material such as rubber, even if it is molding of the product with the shape with overhang, stretch the mold made of the above elastic material. Can be demolded,
There is no need to use a split mold.

Therefore, it is possible to manufacture a ceramic product having an overhang like a drum-shaped cup by cast molding without causing mold scratches.

Further, since it is not necessary to break the mold each time the mold is removed, it can be used repeatedly and is economical.

[Brief description of drawings]

FIG. 1 is a sectional view showing a state at the time of molding by assembling a casting mold for a ceramic product having an overhang portion showing an embodiment of the present invention, and FIG. 2 is a perspective view showing an exploded state. A: Mold that is in charge of molding on the surface side that has the overhang portion (outer mold) B: Mold that is in charge of molding on the surface side other than the surface that has the overhang portion (inner mold) C: Backup member

Claims (1)

(57) [Scope of utility model registration request] 1. A casting molding die for a ceramic product having an overhang portion on either the front or back side, wherein the die in charge of molding the surface side having the overhang portion is made of an elastic material and has the overhang portion. The mold for molding the surface other than the surface is composed of a non-stretchable and water-absorbing material, and the elastic mold is backed up from the back mold to prevent deformation of the mold during molding. Casting mold with a possible backup member.