JPH0525848Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a mold used for pressure casting, and is particularly improved to prevent leakage of slurry, pressurized water, etc. from the molding space inside the mold. This invention relates to a mold for pressure casting.

[Prior Art] Pressure casting is a method in which pressure is applied mainly when carrying out sludge casting, and is widely used today as a method for manufacturing sanitary ware such as toilet bowls and washbasins. To give an overview of this pressure casting casting method, by injecting slurry (sludgy form of powdered clay for molding) into the molding space formed in the mold and pressurizing it, unnecessary parts are removed in the slurry. At the same time, a liquid (e.g. water) is allowed to penetrate into the mold, the remaining powdery clay is deposited on the inner surface of the mold, excess slurry is discharged from the mold, and then the mold is separated. The molded product is then removed.

The mold used for this pressure casting is shown in a side sectional view in FIG. The illustrated mold 1 is for casting a wash basin, and the blank space within the mold is the molding space. The mold 1 includes, from the molding space side, a filtering material layer 2, a backing layer 3, and a pressure-resistant reinforcing layer 4.
The entire mold can be separated into an upper mold 5 and a lower mold 6.

The filtering material layer 2 is formed of a porous synthetic resin (or gypsum), the backing layer 3 is formed of a non-porous synthetic resin (or basa mortar),
The pressure-resistant reinforcing layer 4 is formed of an iron plate or the like. In addition, water is supplied to the filtering material layer 2 under pressure in order to remove water in the slurry by suction during casting, and to form a water film on the molding surface 2a during demolding of the molded product. A porous tube 7 was buried there.

Incidentally, in the mold 1, what is important in fitting the upper mold 5 and the lower mold 6 is that their contact surfaces must rub against each other to the extent that they can be water-sealed. This is because, in pressure casting, as described above, after the slurry is injected into the molding space, the slurry is pressurized to promote the adhesion of the clay. Therefore, conventionally, when the upper mold 5 and the lower mold 6 are assembled, the respective backing layers 3,
3 were made to make strong contact with each other to ensure water-sealing properties.

[Problem to be solved by the invention] In such a mold for pressure casting, foreign matter such as hardened slurry or mold fragments gets caught in the mating surfaces of the split molds (upper mold 5 and lower mold 6 in FIG. 2). When the molds were inserted, the mating surfaces of the split molds did not overlap perfectly, and the slurry sometimes leaked out.

Further, when the split molds are strongly pressed against each other with such foreign matter interposed between the filter material layers of the split molds, the filter material layers may be chipped. (Since this filter material layer is porous, its strength is low and it is easily chipped.) Even if this chipping occurs, the water sealing property is reduced and the slurry leaks out. In addition, if the inked surface side of the elastic material layer is chipped, a burr-like convex portion having a shape that follows the chip will be formed on the surface of the molded product obtained by adding ink, which deteriorates the surface quality of the molded product. .

[Means for Solving the Problems] The pressure casting mold of the present invention is a pressure casting mold formed by combining a plurality of split molds each having a porous filter layer on the inner surface. It is characterized in that an elastic material is provided only in the portion of the filter material along the inlayed surface of the mating surfaces.

[Function] In the pressure casting mold of the present invention, since the elastic material is interposed on the mating surfaces of the split molds, the mating surfaces overlap in a watertight manner, improving water-tightness. Moreover, when this elastic material is interposed, even if foreign matter gets caught in the mating surface, the force with which the foreign matter presses against the mating surface of the split mold is reduced, and chipping of the filter medium layer is also prevented.

Note that this elastic material is provided only on the filtering material layer along the inked surface of the mating surfaces. In this way, even if the mating surfaces of the split molds have some unevenness, the elastic materials provided on each split mold can be brought into close contact with each other. As a result, a tight water seal is formed near the bonded surface of the mating surface, and infiltration of slime into the mating surface is reliably prevented.

[Examples] Hereinafter, the present invention will be described based on drawings showing examples thereof.

FIG. 1 is a partially sectional view showing an enlarged main part of a mold for pressure casting according to an embodiment. This figure roughly corresponds to the arrow A section in FIG. 2 showing the conventional example, and shows a split mold 8 drawn on the upper side (corresponding to the upper mold 5 in FIG. 2) and a lower part. Split mold 9 drawn on the side (second
(corresponding to the lower mold 6 in the figure) are separated vertically.

In this embodiment, an elastic material 10 is provided on the mating surface of the filter material 2 of the lower mold 9. This elastic material 10
In this embodiment, is attached to the mating surface with an adhesive.

Providing such an elastic material 10 improves the water sealing properties of the mating surfaces. Furthermore, even if foreign matter gets caught in the mating surfaces of the upper die 8 and the lower die 9, the force pressing against the filter medium 2 is reduced, and chipping of the filter medium 2 is prevented.

That is, for example, if the upper mold 8 and the lower mold 9 are joined together with foreign matter present on the elastic material 10, the foreign matter will sink into the elastic material 10, and the mating of the upper mold 8 and the lower mold 9 will be interrupted. The surface is tightly water-sealed by the elastic material 10. Further, the force with which the foreign matter presses the filter medium 2 is also small.

Even if foreign matter exists on the mating surface other than the elastic material 10, when joining the upper mold 8 and the lower mold 9,
The upper mold 8 and the lower mold 9 are made by the thickness of the elastic material 10 after compression.
A clearance exists between the parts other than the elastic material 10. For this clearance,
The force with which the foreign matter presses the filter medium 2 is reduced, and chipping of the filter medium 2 is prevented.

In the present invention, the elastic material 10 is a soft porous material with closed pores. By forming independent pores, slime does not penetrate, the elasticity of the elastic material 10 becomes permanent, and sufficient water sealing properties are obtained.

A preferable example of the elastic material is urethane sponge. The width b of the elastic material 10 is 3 to 50 mm
The elastic material 10 is preferably provided only on the filter material 2. The elastic material 10 is 0.2~
Preferably, the thickness is about 3 mm.

By bonding this elastic material 10 with an adhesive, its position remains unchanged, making it easier to mold. Furthermore, even if water pressure is applied during demolding, the elastic material will not peel off. However, the present invention does not require the use of adhesive. Preferred adhesives include those based on modified polyamines.

As shown in the figure, it is preferable to provide the elastic material 10 slightly recessed from the surface of the filter material 2 to be coated. When the elastic material 10 is provided recessed in this manner, when the upper mold 8 and the lower mold 9 are joined together and pressed against each other, the elastic material 10
Even if the elastic material 10 spreads in the mating surface direction, the elastic material 10 is prevented from protruding from the inlay surface. The recession a is preferably 1 to 20 mm, and more preferably 5 to 10 mm. Even if a foreign object gets caught in the recession a, there is a clearance of the compressed thickness of the elastic material 10, so that the filter material 2 is prevented from being chipped, and
There is sufficient water sealing.

Although the above embodiment relates to one having a backing layer 3,
The present invention can also be applied to a structure in which the filter material 2 is in direct contact with the pressure-resistant reinforcing layer 4.

Furthermore, in the embodiment described above, since the proposed structure was applied to a mold for casting a washbasin, the mold forming parts 8 and 9 corresponded to the upper mold and the lower mold, respectively. However, when implementing the proposed structure in a mold for casting toilet bowls (particularly Western-style toilet bowls), etc., a back mold, a core mold, etc. are added in addition to the upper and lower molds. In this case, an elastic material may be provided on the mating surface of each mold as described above.

[Effects of the invention] As is clear from the above explanation, according to the pressure casting mold according to the invention, there is no leakage of slurry or pressurized water at the mating surfaces of the filter material layers, so there is no burr in the molded product. will never occur. Therefore, there is no need to remove burrs every time before drying of the molded product begins, and the efficiency of the entire casting operation is improved. Furthermore, when manufacturing split molds, it is no longer necessary to precisely finish the flatness and smoothness of the mating surfaces of the split molds, and so on.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view showing an enlarged main part of the proposed structure, and FIG. 2 is a side sectional view showing a conventional mold. 2...filtering material layer, 3...backing layer, 4...pressure-resistant reinforcing layer, 8, 9...split mold, 10...elastic material.

Claims (1)

[Scope of utility model registration request] In a pressure casting mold formed by combining a plurality of split molds each having a porous filter layer on the inner surface,
A mold for pressure casting, characterized in that an elastic material is provided only in the part of the filter material along the inking surface of the mating surfaces of the split molds.