JP2007275923A - Method for manufacturing gypsum mold in gypsum casting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a gypsum mold in a gypsum casting method with which a portion easily broken in the gypsum mold at the time of separating from a rubber mold can be reinforced without fearing the development of cracking in the gypsum mold and the repairing work, etc., of the gypsum mold after manufacturing can be reduced. <P>SOLUTION: In a land part 3a of the gypsum mold 3, a reinforcing member 4 composed of linear materials is embedded in the portion easily broken in the gypsum mold 3 at the time of separating from the rubber mold 1. The reinforcing member 4 is the one formed as a basket-like by bending at least one piece of linear material 4x in three-dimensional-state shown in Fig.2 and the reinforcing member 4 formed as the basket-like by curving the linear material 4x in the center part of the land part 3a of the gypsum mold 3. The linear material of wire diameter of 4x having 0.05-2.0 mm, desirably 0.1-1.0 mm diameter, is used, and the material of the linear material 4x uses a metal (metallic wire, such as steel wire, ceramic wire material, etc.) having high heat resistance, or non-metallic material (fiber having heat resistance, for example, glass fiber, carbon fiber, etc.). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for producing a gypsum mold in a gypsum casting method. More specifically, the gypsum mold poured into a rubber mold is cured (completely dried) or semi-cured (semi-dried), and the rubber mold is removed from the gypsum mold. The present invention relates to a method for manufacturing a gypsum mold in a gypsum casting method, which enables mold release so that a defective portion does not occur in a part of the gypsum mold when releasing the mold.

  Conventionally, as a method of producing a gypsum mold in the gypsum casting method, a gypsum that has been slurried with a predetermined moisture content is poured into a rubber mold that has been previously formed into a shape corresponding to a molding die, and the gypsum is cured (completely dried). ) Or in a semi-cured (semi-dried) state, the rubber mold is released from the gypsum mold. Then, using the gypsum mold manufactured as described above as a mother mold, a molten metal is poured into a mold for molding.

  In addition, as a method of manufacturing a gypsum mold in which a siping blade is embedded in a gypsum mold, for example, as shown in FIGS. 12 and 13, a siping blade 2 is implanted in a rubber mold 1 in this state. A gypsum made into a slurry with a predetermined moisture content is poured into the rubber mold 1, the rubber mold 1 is released from the gypsum mold 3 in a state where the gypsum is cured or semi-cured, and the siping blade 2 is removed from the surface of the gypsum mold 3. Form a part protruding.

  By the way, since the gypsum mold 3 is obtained by removing water (natural drying, forced drying) from the gypsum made into a slurry, the gypsum mold 3 is very brittle, and when the rubber mold 1 is released, a part Qa of the gypsum mold 3 is formed. There is a problem that it is easily lost or sharp corners of the land are easily lost. For this reason, repair is sometimes performed after the production of the gypsum mold.

  In particular, when the rubber mold 1 is easily removed from the gypsum mold 3, the gypsum is formed as shown in FIGS. 14 (a), 14 (b), 15 (a), 15 (b) and FIG. When the area of the siping blade 2 embedded in the mold 3 is relatively smaller than the area embedded in the rubber mold 1, or when the siping blade 2 is disposed at the corner of the land portion 3a of the gypsum mold 3, When the rubber mold 1 is released from the gypsum mold 3, there is a problem that the siping blade 2 is pulled to the rubber mold 1 side and a defective part Q is generated in the thin part t of the gypsum mold 3. In addition, when the land portion 3a of the gypsum mold 3 has an acute angle portion, the defective portion Q is easily generated.

  Therefore, in order to prevent a part of the gypsum mold from being lost when the rubber mold is released, a method of manufacturing a tire molding mold in which a rod-like or plate-like reinforcing material is embedded inside the gypsum mold has been proposed. (For example, refer to Patent Document 1).

However, in the method of embedding a rod-like or plate-like reinforcing material, the volume change due to thermal expansion is large, there is a risk of cracking in the gypsum mold, and the shape cannot be arbitrarily set. There is a problem that it is difficult to arrange the ping blade so as to cover the ping blade, and it is particularly difficult to reinforce the acute angle portion of the land portion of the gypsum mold.
Japanese Patent Laid-Open No. 11-170267 (Japanese Patent No. 3179748)

  The present invention pays attention to such conventional problems, and by using a heat-resistant reinforcing member obtained by knitting a linear material into a predetermined shape, there is no risk of cracking in the gypsum mold, and the release of the rubber mold It is an object of the present invention to provide a method for producing a gypsum mold in a gypsum casting method that can reinforce a portion of the gypsum mold that is easily damaged and can reduce repair work of the gypsum mold after production.

  In order to achieve the above object, the present invention has a heat resistance in which a linear material is knitted into a predetermined shape at a part where gypsum is likely to be lost when the gypsum is poured into the rubber mold and when the rubber mold is released. The gist of the present invention is to manufacture a gypsum mold by disposing a rubber mold after disposing a reinforcing member, and in this state pouring gypsum and curing or semi-curing the reinforcing member in an embedded state. .

  Here, a small amount of gypsum is poured into the rubber mold in advance, and a reinforcing member in which a linear material is knitted into a predetermined shape is disposed at a site where a loss of gypsum is likely to occur when releasing the rubber mold in this state, It is also possible to pour the remaining gypsum.

  In addition, a predetermined amount of gypsum having a low water content is poured into the rubber mold in advance, and a reinforcing member in which a linear material is knitted into a predetermined shape is disposed at a site where the gypsum is likely to be lost when the rubber mold is released in this state. It is also possible to pour gypsum with a higher water content.

  Here, the portion where the plaster chipping is likely to occur is reinforced so as to cover the periphery of the siping blade when stress is concentrated when the rubber mold is released or when the siping blade is implanted. A reinforcing member is formed by bending at least one linear member in a three-dimensional shape to form a bowl shape, and the reinforcing member is a linear member having a wire diameter of 0.05 mm to 2.0 mm. The material of the linear material is a metal or non-metallic material having heat resistance.

  In this way, by using a heat-resistant reinforcing member knitted from a linear material into a predetermined shape, it is possible to reinforce the gypsum mold part that tends to be lost when the rubber mold is released, and repairing the gypsum mold after production Etc. can be reduced.

  This invention is a pre-process for pouring gypsum into a rubber mold as described above, and has heat resistance reinforcement in which a linear material is knitted into a predetermined shape at a site where the gypsum is likely to be lost when the rubber mold is released. In this state, the gypsum is poured and the reinforcing member is embedded and cured or semi-cured, and then the rubber mold is released to produce the gypsum mold. It is what you play.

(a) By using a linear member having heat resistance of a predetermined diameter as the reinforcing member, there is little influence of thermal expansion, and there is no possibility of cracking in the plaster mold.
(b) It is possible to reinforce a portion where the gypsum mold is easily damaged when the rubber mold is released, and to reduce the repair work of the gypsum mold after manufacturing.
(c) Even when the area of the siping blade embedded in the gypsum mold is relatively smaller than the area embedded in the rubber mold, it is possible to effectively prevent the gypsum mold from being lost when the rubber mold is released.
(d) Even when the siping blade is disposed at the corner of the land portion of the gypsum mold, it is possible to effectively prevent the gypsum mold from being lost when the rubber mold is released.
(e). Even if the land portion shape of the gypsum mold is sharp, no defect occurs.
(f) By using a linear material having heat resistance of a predetermined diameter for the reinforcing member, the reinforcing member can be configured in an arbitrary shape, and can be disposed at an arbitrary position of the rubber mold and poured in gypsum.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
In addition, the same component as a prior art example attaches | subjects the same code | symbol, and abbreviate | omits description.

  FIG. 1 is a perspective view of a gypsum mold 3 showing a first embodiment of the present invention. In the land portion 3a of the gypsum mold 3, the gypsum mold 3 is broken when the rubber mold 1 is released. A reinforcing member 4 made of a linear material is embedded in an easy portion.

  As shown in FIG. 2, the reinforcing member 4 is formed by bending at least one linear material 4 x in a three-dimensional shape to form a hook-like shape, and in the central portion of the land portion 3 a of the gypsum mold 3, the linear material is formed. A reinforcing member 4 formed in a bowl shape by curving 4x is embedded. The wire diameter of the linear material 4x is 0.05 mm to 2.0 mm, preferably 0.1 mm to 1.0 mm, and the material of the linear material 4x is a heat-resistant metal (such as a steel wire). Metal wires, ceramic filament materials, etc.) or non-metallic materials (heat-resistant fibers such as glass fibers, carbon fibers, etc.) are used.

  In addition, when the wire diameter is less than 0.05 mm, there is no rigidity, and when it exceeds 2.0 mm, there are problems in thermal expansion and workability, and further, the material is preferably less affected by heat.

  In the embodiment of FIG. 3, the reinforcing member 4 is embedded in the corner portion of the land portion 3a of the gypsum mold 3 by bending at least one linear material 4x in a three-dimensional shape to form a hook shape, Furthermore, the embodiment of FIG. 4 is a case where a single linear material 4x is bent into a three-dimensional shape by folding it into a spiral shape, and this is embedded in the central portion of the land portion 3a of the gypsum mold 3. FIG. This is a case where the linear material 4x is arbitrarily bent into a three-dimensional shape and embedded in the central portion of the land portion 3a of the gypsum mold 3.

  Moreover, FIGS. 6-8 is embodiment which implants the siping blade 2 in the one side of the land part 3a of the gypsum mold 3, In this embodiment, when implanting the siping blade 2 in the perpendicular direction, A reinforcing member 4 formed by bending a linear material 4x in a three-dimensional shape around a buried portion is provided. In particular, even when the area of the siping blade 2 embedded in the gypsum mold 3 is relatively smaller than the area embedded in the rubber mold 1, the loss of the gypsum mold 3 when the rubber mold 1 is released can be effectively prevented.

  FIG. 9 shows an embodiment in which the reinforcing member 4 formed in a hook shape by bending the linear material 4x in a three-dimensional shape is disposed in the rubber mold 1, and the loss of the gypsum mold 3 when the rubber mold 1 is released. It can be effectively prevented.

Next, a method for manufacturing a gypsum mold will be described.
The gypsum mold manufacturing method according to the first embodiment of the present invention is as follows. First, the gypsum mold 3 is damaged before the gypsum is poured into the rubber mold 1 and when the rubber mold 1 is released. A heat-resistant reinforcing member 4 knitted into a predetermined shape is disposed. In this state, gypsum is poured into the reinforcing member 4 and cured (completely dried) or semi-cured (semi-dried), and then the rubber mold 1 is released to manufacture the gypsum mold 3.

  When the rubber mold 1 is released, the semi-cured (semi-dried) gypsum mold 3 has no strength and is easily damaged. In the embodiment of the present invention, the reinforcing member 4 is embedded as described above. For this reason, the rubber mold 1 can be released without being lost even if the strength of the gypsum mold 3 is weak.

  The part where the plaster chipping is likely to occur is a part where stress is concentrated when the rubber mold 1 is released, and when the siping blade 2 is implanted, By disposing the reinforcing member 4 so as to cover the surface, it is possible to prevent the rubber mold 1 from being damaged when released.

  Moreover, as other embodiment of the manufacturing method of the gypsum mold 3, as shown to Fig.10 (a)-(c), a small amount of gypsum Sa is poured into the rubber mold 1 beforehand, and the rubber mold 1 is made in this state. A reinforcing member 4 in which a linear material 4x is knitted in a predetermined shape is disposed at a site where the gypsum is likely to be lost when the mold is released, and the remaining gypsum Sb is poured to reinforce the surface of the gypsum mold 3. The gypsum mold 3 can be manufactured without exposing the terminal portion of the member 4.

  Moreover, as other embodiment of the manufacturing method of the gypsum mold 3 shown to Fig.11 (a)-(c), slurry-like gypsum Sx with high water content, and slurry-like gypsum Sy with low water content beforehand A predetermined amount of gypsum Sy (hard gypsum) with a low water content is poured into the rubber mold 1 in advance, and when the rubber mold 1 is released in this state, the gypsum is easily broken. By arranging the reinforcing member 4 knitted from the material 4x into a predetermined shape and pouring gypsum Sx (soft gypsum) having a high water content, the end portion of the reinforcing member 4 is not exposed on the surface of the gypsum mold 3. It becomes possible to manufacture the gypsum mold 3.

  Thus, by dividing and pouring gypsum at the time of manufacture, the reinforcing member 4 does not protrude or be exposed on the surface of the gypsum mold 3, and does not affect the production of the molding die.

  By producing the gypsum mold 3 by the method as described above, there is no risk of cracking in the gypsum mold, and it is possible to reinforce a portion where the gypsum mold 3 is easily lost when the rubber mold 1 is released. Repair work of the plaster mold 3 can be reduced. Further, even when the area of the siping blade 2 embedded in the gypsum mold 3 is relatively smaller than the area embedded in the rubber mold 1, it is possible to effectively prevent the gypsum mold 3 from being lost when the rubber mold 1 is released.

1 is a perspective view of a gypsum mold in which a reinforcing member showing a first embodiment of the present invention is embedded. FIG. It is a perspective view of the linear material of a reinforcement member. It is a perspective view of other embodiments of the gypsum mold which embedded a reinforcement member. It is a perspective view of other embodiments of the gypsum mold which embedded a reinforcement member. It is a perspective view of other embodiments of the gypsum mold which embedded a reinforcement member. It is a top view of the plaster mold which provided the reinforcement member around the siping blade. It is an AA arrow front view of FIG. It is BB arrow sectional drawing of FIG. It is sectional drawing of the rubber type which embed | buried the reinforcing member knitted in the hook shape. (A)-(c) is process drawing of the other manufacturing method of a gypsum mold. (A)-(c) is process drawing of the other manufacturing method of a gypsum mold. It is sectional drawing of the manufacturing method of the conventional gypsum mold. It is sectional drawing of the manufacturing method of the gypsum mold at the time of mold release of the conventional rubber mold. (A), (b) is the top view of the gypsum mold at the time of mold release of a rubber type | mold, and explanatory drawing of the defect | deletion state. (A), (b) is the front view of the gypsum mold at the time of mold release of a rubber mold, and explanatory drawing of the defect | deletion state. It is explanatory drawing of the other defect | deletion state of a gypsum mold.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rubber mold 2 Siping blade 3 Gypsum mold 3a Land part Q, Qa Deletion part t Thin part 4 Reinforcement member 4x Linear material Sx Gypsum with high water content Sy Gypsum with low water content

Claims (7)

In the method for producing a gypsum mold in a gypsum casting method, a gypsum casting method for producing a gypsum mold by pouring gypsum into a rubber mold and releasing the rubber mold in a state where the gypsum is cured or semi-cured.
A heat-resistant reinforcing member in which a linear material is knitted into a predetermined shape is disposed in the rubber mold in a step before pouring gypsum and the gypsum is likely to be lost when the rubber mold is released. A method for producing a gypsum mold in a gypsum casting method, wherein gypsum is poured in a state and cured or semi-cured in a state where a reinforcing member is embedded, and then a gypsum mold is produced by releasing a rubber mold.   A small amount of gypsum is poured into the rubber mold in advance, and a reinforcing member in which a linear material is knitted into a predetermined shape is disposed at a portion where the gypsum is likely to be lost when the rubber mold is released in this state. The method for producing a gypsum mold in the gypsum casting method according to claim 1, wherein gypsum is poured.   A predetermined amount of gypsum with a low water content is poured into the rubber mold in advance, and a reinforcing member in which a linear material is knitted into a predetermined shape is disposed at a site where the gypsum is likely to be lost when the rubber mold is released in this state. The method for producing a gypsum mold in the gypsum casting method according to claim 1, wherein a gypsum having a higher water content is poured.   The part where the plaster chipping is likely to occur is a part where stress is concentrated when releasing the rubber mold, or when a siping blade is implanted, a reinforcing member is arranged so as to cover the periphery of the siping blade. A method for producing a gypsum mold in the gypsum casting method according to claim 1, 2 or 3.   5. The method for producing a gypsum mold in the gypsum casting method according to claim 1, wherein the reinforcing member is formed into a bowl shape by bending at least one linear material in a three-dimensional shape.   6. The method for producing a gypsum mold in the gypsum casting method according to claim 1, wherein the reinforcing member is a linear material having a wire diameter of 0.05 mm to 2.0 mm.   7. The method for producing a gypsum mold in the gypsum casting method according to claim 1, wherein the linear material is a heat-resistant metal or non-metal material.

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