JP2569203B2 - Casting mold - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a casting mold used in a casting method capable of reducing loss of raw materials during molding and improving product yield. .

(Prior art) In cast molding of ceramic products, metal products, ferrite products, etc., water-absorbing gypsum molds, porous resin molds, porous metal molds and the like are used, and slurry is poured into their cavities. After the injection and the elapse of a predetermined time, the remaining slurry is discharged to form a product base body having a required thickness on the inner surface of the cavity. However, in a slurry injection / discharge path such as a casting passage, a casting port, or a discharge port for guiding the slurry into the cavity, the water in the slurry is absorbed during the injection, molding, or discharge of the slurry, and the slurry is injected and discharged. As the solidification of the slurry component existing in the passage progresses, the slurry supply for replenishing the volume shrinkage of the product base in the cavity becomes insufficient, and the product base body becomes defective or deformed. It is necessary to prevent sludge from occurring in products that require sludge, as this may cause a lack of smoothness. As a method, it is desired to apply a non-water-absorbing material layer by applying an acrylic resin or inserting a vinyl chloride resin or a stainless steel pipe on an inner surface of a slurry injection and drainage passage connected to a cavity.
No. 20 (Japanese Utility Model Laid-Open No. 61-40208) describes the microfilm, but also forms a non-water-absorbing material layer on the slurry injection and drainage passage connected to the cavity by coating or inserting a pipe. However, when the mold is complicated and expensive, and when the injection / ejection path has a complicated shape, it cannot be followed. However, there is a problem that it takes a long time and the workability is extremely poor.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned conventional problems and completely prevents the absorption of water from the slurry in the slurry injection and discharge path to efficiently form a cast product base body. It has been completed with the object of providing a casting mold that can be manufactured and can be provided easily and at low cost, and that can also perform slurry injection and discharge of a plurality of mold cavities with one slurry injection and discharge path. Things.

(Means for Solving the Problems) A casting mold according to the present invention made to solve the above-mentioned problems is characterized in that a slurry is injected into a cavity, and after a lapse of a predetermined time, the remaining slurry is discharged. In a casting mold for molding a product base body having a required thickness, a mold (1) is divided into a mold body having a cavity formed therein and a slurry holding mold placed on the mold body. The molding die body is also a split mold, and a waterproof synthetic resin is adhered and integrated with the division surface between the molding die body and the slurry holding die and the division surface of the molding die body forming the casting port. The method is characterized in that a slurry injection passage covered with a thin film layer is provided.

(Embodiment) The drawings show embodiments of the present invention. In the drawings, (1) shows a mold made of gypsum, porous resin, porous metal, etc. having water absorbency. 1) is a split mold comprising a mold body (1a) in which a cavity (2) for molding a product body is formed and a slurry holding mold (3) placed on the mold body (1a). The slurry is injected into the inside and cast. The molding die body (1a) is of a two-part type, and has a short straight casting port (4) following the cavity (2) as a slurry injection drain on the division surface thereof. The inner peripheral surface of the entrance (4) is coated with a waterproof synthetic resin thin film layer (5), and the dividing surface between the mold body (1a) and the slurry holding mold (3) is A casting passage (7) is formed as a slurry injection drain covered with the synthetic resin thin film layer (5) having the same waterproof property as that described above, and covered with the synthetic resin thin film layer (5) integrated and bonded. I have.

As a synthetic resin thin film layer (5), in the presence of moisture, and
Epoxy resin and acrylic resin, which are hardened at a low temperature of 70 ° C or less and are partially impregnated into the inner surface of the casting port (4) and are strongly adhered to reinforce the pouring channel, which are excellent in wear resistance And a polyester resin are preferable. In order to further improve the curability at a low temperature, a polyamide-based, modified amine-based, or self-emulsifying fatty polyamide-based curing agent may be added and used in an appropriate amount.

When casting using such a mold (1),
Slip holding mold (3) placed on the mold body (1a)
When the slurry is injected from the casting passage (7), the slurry injected from the casting passage (7) is guided to the casting port (4) from the casting passage (7), and then the cavity (2). The product (10) having a complicated shape is cast by being injected into the inside, and the casting passage (7) as the slurry injection and discharge port and the casting port (4) are waterproof. Since the synthetic resin thin film layer (5) having
Water absorption of the mud in this portion is reliably prevented by the waterproof synthetic resin thin film layer (5), so that the mud does not solidify and accumulate in the casting port (4), and the initial molding process and replenishment during the process Injection of the slurry into the cavity (2) in the process is performed extremely smoothly, and the yield of the product is remarkably improved, and the diameter of the casting port (4) can be reduced. Reduction can be achieved. Furthermore, the concentration of the slurry recovered from the casting port (4) is the same as that at the time of injection,
Since there is no foreign matter, the material can be reused as it is, thereby preventing the loss of raw materials. Further, there are various advantages such that one mold holding mold (3) can correspond to a plurality of molding die bodies (1a). Further, in the present invention, the slurry reinforced by the synthetic resin thin film layer is provided. Since the pouring / discharging path is formed on the dividing surface between the molding die body (1a) and the slurry holding die (3), a complicated shape suitable for pouring and discharging the slurry can be easily obtained. Therefore, there is an effect that an object can be formed according to the mold along the mold.

EXPERIMENTAL EXAMPLE 1 A split mold made of a porous synthetic resin as shown in FIG. 1 was manufactured, and an epoxy resin (Epicoat 828: Shell Petrochemical Co., Ltd.) was placed on the inner peripheral surface extending from the casting port to the casting passage at 25 ° C. A resin thin film layer composed of 100 g, a hardening agent (Sunmide M1001: Sanwa Chemical Industry Co., Ltd.) 28 g and calcium carbonate 35 g was cured and bonded to form a synthetic resin thin film layer. After that, 100 g of alumina powder (AL160SG III: manufactured by Showa Light Metal Co., Ltd.), 0.2 g of ammonium polycarboxylate, 0.8 g of acrylate, and 28 g of water were injected and mixed with alumina slurry to perform casting. Even after the continuous molding, the solidification of the slurry did not occur in the casting port and the casting passage, and the molding was able to be performed extremely favorably, confirming the excellent effect of the present invention.

(Effects of the Invention) As is clear from the above description, in the present invention, the synthetic resin thin film layer having a waterproof property is coated and formed integrally with the inner peripheral surface of the slurry injection and discharge passage following the cavity. Completely preventing the absorption of water from the slurry in the injecting and discharging channels, enabling continuous molding of cast products with high efficiency.Continuous molding can be performed, so workability is excellent and the discharged slurry can be reused. It can be produced without any loss of raw materials and can exhibit excellent effects economically. Moreover, the slurry injection and drainage channel reinforced by the application of the waterproof synthetic resin thin film layer is not a mold body having a cavity having a complicated shape, but a dividing surface between the mold body and the slurry holding mold and a casting surface. Since it is provided on the divided surface of the molding die main body that can form the entrance, it can easily and accurately form the slurry injection channel reinforced with the synthetic resin thin film layer without requiring troublesome work, and it can be provided at low cost, Further, there is an advantage that a single slurry holding mold can be combined with a plurality of molding die bodies to perform slurry injection and discharge of the cavity.

Therefore, the present invention greatly contributes to industrial development as a casting mold for eliminating the conventional problems.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention. (1): Mold, (1a): Mold body, (2): Cavity, (3): Slurry holding mold, (4) Casting port, (5): Synthetic resin thin film layer, (7): Casting passage.

Claims (2)

(57) [Claims] In a casting mold, a slurry having a required thickness is formed on an inner surface of a cavity by injecting a slurry into a cavity and discharging a remaining slurry after a predetermined time elapses. ) Is a split mold comprising a mold body (1a) having a cavity (2) formed therein and a slurry holding mold (3) placed thereon, and the mold body (1a) is also a split mold, And a waterproof synthetic resin that is integrally bonded to the division surface between the molding die body (1a) and the slurry holding die (3) and the division surface of the molding die body (1a) forming the casting port (4). A casting mold having a slurry injection / discharge path covered with a thin film layer (5). 2. The casting mold according to claim 1, wherein the synthetic resin thin film layer (5) is cured at a temperature of 70 ° C. or less in the presence of moisture.