JPS61266211A - Molding tool for liquid casting resin - Google Patents

Abstract

PURPOSE:To improve the accuracy of configuration of a cavity and facilitate the mold release of products by a method wherein a resin plaster outer die, provided with protuberances fitted into the thickness of male portion of a silicon rubber male mold, is provided at the outside of the silicon rubber male mold and female mold. CONSTITUTION:The cavity 12, having the configuration of a product W1, is formed under a condition that both of the silicon rubber male mold 10 and the silicon rubber female mold 11 are clamped. The upper surface of silicon rubber female mold 11, joined at the upper side of the male mold 10, is connected integrally to the resin plaster outer die 14 through mushroom type pins 16, therefore, drooping of the upper surface of the female mold 11 is prevented while the protrusions 17 of the outer die 13 are fitted into the thickness of male portion of the male mold 10, therefore, the protuberances 17 effect the role of reinforcing bones and tilting of the male portion of silicon male mold 10 may be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a mold for injecting a liquid resin into the mold and solidifying the resin.

<Prior Art> When casting liquid resin, a silicone rubber mold having a cavity shaped like the product is used. For example, as shown in FIG. 3, when molding a product cylinder in the shape of a comb or a tooth shape, a mold made of a silicone rubber male mold 1 and a silicone rubber female mold 2 having a cavity 3 in the shape of the product W1 is used. It is.

<Problems to be solved by the invention> In the conventional silicone rubber mold described above, as shown in FIG.
A droop 4 occurs on the upper surface of the upper silicone rubber female mold 2, resulting in a misalignment between the silicone rubber female mold 2 and the silicone rubber male mold 1 as shown in FIG. The thickness of the product W1 becomes uniform, and a defective product is formed in which the thickness of the product W1 is non-uniform.

Further, as shown in FIG. 7, there is also a cylindrical product W2 having a small external width and a large external width and thickness. The silicone rubber mold in this case is a combination of a silicone rubber male mold forming a cavity 3α in the shape of the product W2 and a silicone rubber female mold 2α, as shown in FIG. As shown in , the silicone rubber female mold 2α can be opened and released, but the product vortex attached to the silicone rubber male mold 1α side has a small width because the width B′ of the tip of the silicone rubber male mold 1a is large. There is a problem that the part X cannot be removed and the product W2 cannot be released from the mold.

<Means for Solving the Problems> In order to solve the above problems, the present invention provides silicone rubber male and female molds having product-shaped cavities, silicone rubber male and female molds surrounding the outsides, and silicone rubber molds surrounding the outsides of the silicone rubber male and female molds. It has a composite structure with a resin plaster outer mold having a protrusion that fits into the thickness of the male part of the rubber male mold.

Function> In the present invention, the resin plaster outer mold acts as an outer shell of the silicone rubber inner mold, maintains the shape of the silicone rubber inner mold, and
The resin plaster outer mold becomes a straight male mold, and a cavity is formed in the silicone rubber inner mold, giving the silicone rubber inner mold shrinkage deformability and facilitating product release.

(Example) Examples of the present invention will be described below based on FIGS. 1 and 2. FIG. 1 shows a mold for molding the product W1 shown in FIG. 11 is a silicone rubber male mold, and 11 is a silicone rubber female mold, which has a cavity 12 in the shape of the product when both molds are put together.13 is the outer side of the silicone rubber male mold 10. A resin plaster outer mold 14 surrounds the silicone rubber female mold 11. A resin plaster outer mold 13I surrounds the silicone rubber male mold 10.
A straight protrusion 17 is provided that fits into the male part thickness of 0. Further, the upper surface of the silicone rubber female mold 11 surrounded by the resin plaster outer mold 14 is integrally joined by a mushroom-shaped bottle 16 embedded in the resin plaster outer mold 14.

Reference numeral 15 denotes a knock pin for positioning and connecting the mating surfaces of both resin plaster outer molds 13 and 14.

FIG. 2 shows a mold for molding the product grapes shown in FIG. 7 as an example. In this case as well, the silicone rubber male mold 1
0, silicone rubber female mold 11, resin plaster outer mold 13.14,
Consisting of a straight protrusion 17, a silicone rubber male,
A cavity 12 having a shape of +5?1w2 is formed by the female molds 10 and 11.

Since the present invention has the structure as described above, resin plaster outer mold 1
3.14 becomes the outer shell of the silicone rubber male and female molds 11.12, and maintains the form of the silicone rubber male and female molds 11.12. Especially in the case of the mold shown in Fig. 1, the silicone rubber male mold 1
Since the upper surface of the silicone rubber female mold 11 that is fitted above the mold 1 is integrally connected to the resin plaster outer mold 14 by the mushroom-shaped bottle 16, the upper surface of the silicone rubber female mold 11 is prevented from sagging. In addition, since the male part of the silicone rubber male mold 10 has a protrusion 17 of the resin plaster outer mold 13 fitted into its wall thickness, this protrusion 17 acts as a reinforcing bone, and the silicone rubber male mold 10 Prevents the male part from falling down. Therefore, the cavity 12 maintains a predetermined shape with high precision.

On the other hand, in the case of the mold shown in Fig. 2, it goes without saying that the shape retention of the male and female silicone rubber molds 10 and 11 and the highly accurate retention of the shape of the cavity 12 have the same effect as described above. , it is possible to release the product from the mold.

That is, the silicone rubber female and male molds 11 and 10 are extracted from the resin plaster outer mold 14 together with the resin plaster outer mold 13 side.

Therefore, by opening the silicone rubber female mold 11, the product W
The mold is released from the outside of 2. Next, the silicone rubber male mold 10 is released from the resin plaster outer mold 13. As a result, a cavity is formed in the male part of the silicone rubber male mold 10 into which the protrusion 17 was fitted.

By collapsing this cavity, the silicone rubber male mold 10 is contracted and deformed, and a product having large and small steps in the punching direction can be easily released from the mold.

<Effects of the Invention> As described above, according to the present invention, the resin plaster outer mold surrounding the outside of the silicone rubber male and female molds prevents deformation of the silicone rubber male and female molds, and improves the shape accuracy of the cavity. However, it has the advantage of improving the product accuracy and reproducibility of the injection resin, and also makes it possible to release bag-shaped products with a wide tip, making it possible to carry out cast molding of this type of shape. are doing.

[Brief explanation of the drawing]

Figures 1 and 2 are cross-sectional views of the mold of the present invention, Figure 3 is a perspective view showing an example of the product, and Figure 4 is a cross-sectional view of a conventional mold for casting the product shown in Figure 3. , Fig. 5 and Fig. 6 are explanatory diagrams of problems with conventional molding molds, Fig. 7 is a perspective view showing another example of the product, and Fig. 8 is a molding when casting the product in Fig. 7. The cross-sectional view of the mold, FIG. 9, is an explanatory view of the problem with the mold shown in FIG. 8. 10@...Silicone rubber male mold, 11...Silicone rubber female mold, 12...Cavity, 13.14...Resin plaster outer mold, 17...Protrusion.

Claims (1)

[Claims] It is a mating mold for casting and molding liquid resin, and includes silicone rubber male and female molds having product-shaped cavities, and a male portion of the silicone rubber male mold surrounding the outside of the silicone rubber male and female molds. A liquid casting resin mold consisting of a composite structure with a resin plaster outer mold equipped with a protrusion that fits into the thickness.