JPH0684023B2 - Molding equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a molding die apparatus for molding a container such as a bathtub or a washbasin.

[Background Art] Conventionally, for example, when molding a bathtub by cast molding,
As shown in the figure, a concave mold portion 4'opened upward in the lower mold 1 '.
The upper mold 3'is provided with a convex mold part 2'projecting downward, and the upper and lower molds 3 ', 1'are clamped to form a resin filling space 6'with the concave mold part 4'and the convex mold part 2'. To form the resin filling space 6 '.
The gas venting portion 7'is provided so as to communicate with the upper portion of the resin and the resin supply portion 8'is provided so as to communicate with the lower portion, and the resin is filled into the resin filling space 6'from the resin feeding portion 8'that communicates with the lower portion. The gas was vented from the degassing part 7'as it was done. However, in this case, the gas rises from the bottom to the top as shown by the arrow A in FIG. 6 and rises along the convex portion 2 ', but at this time, the gas is generated on the inner surface of the convex portion 2'. There is a problem in that the product remains because it remains and becomes a nest, and a nest appears on the inner surface of the bathtub which is a molded product. In addition, a resin supply part communicating with the upper part of the resin filling space is provided, and a gas vent part is provided so as to communicate with the lower part of the resin filling space, and the resin is transferred from the upper resin supply part to the resin filling space. There is also one that is supplied and molded, but in this one, since the resin is naturally dropped from the upper resin supply part, the resin does not flow uniformly and it is easy to form cavities. However, there is a problem that product defects are likely to occur.

[Object of the Invention] The present invention has been made in view of the above points, and an object of the present invention is to make it possible to prevent formation of cavities or the like on the inner surface of a container-shaped molded article with a simple configuration. A mold tool is provided.

DISCLOSURE OF THE INVENTION In the molding die apparatus of the present invention, a convex mold portion 2 having an upper portion wider than a lower portion is projected upward on an upper surface portion of a lower mold 1, and a convex mold portion 2 is downward on a lower surface portion of an upper mold 3. A concave mold part 4 having a lower part which is open to the upper part and which is recessed upward is wider than the upper part, and the upper and lower molds 3 and 1 are clamped to form a container-shaped molded product 5 by the convex mold part 2 and the concave mold part 4. To form a resin filling space 6 for forming a resin, and to provide a gas vent 7 communicating with an upper portion of the resin filling space 6 and a resin supply portion 8 communicating with a lower portion of the resin filling space 6. It is characterized by being provided, and by adopting such a configuration, the object of the present invention is achieved by solving the above-mentioned conventional problems, that is, the gas flows from bottom to top. Upon rising, it rises from the convex mold portion 2 surface side toward the concave mold portion 4 surface side, and rises along the concave mold portion 4 surface. Thus, the gas does not accumulate on the surface of the convex portion 2 and no cavity is formed on the inner surface of the container-shaped molded product.

Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the accompanying drawings.

FIG. 1 shows an embodiment of the molding die of the present invention. The lower mold 1 has a convex mold portion 2 protruding upward from the upper surface thereof. The upper portion of the convex portion 2 is wider than the lower portion. On the lower surface of the upper mold 3, there is formed a concave mold part 4 which is open downward and is concave upward, and the lower part of the concave mold part 4 is wider than the upper part. A resin-filling space 6 for molding a container-shaped molded product 5 is formed by clamping the upper mold 3 and the lower mold 1 having the above-described configuration. As described above, the upper and lower molds 3, 1 constitute the molding die A. In the present invention, the upper portion of the molding die A is provided with the gas vent portion 7 communicating with the upper portion of the resin filling space 6. There is. Further, a resin supply portion 8 communicating with the resin filling space 6 is provided below the molding die A. In the embodiment of the accompanying drawings, the resin filling space 6
The upper die 3 is provided with a gas vent 7 so as to communicate with the uppermost end of the lower die 1, and a protrusion 9 is provided on the peripheral portion of the lower die 1 to form a resin filling space 6 in the protrusion 9. A resin supply unit 8 that communicates is provided. When the upper die 3 and the lower die 1 are clamped, the above-mentioned protrusion 9
A recess 10 is provided for fitting with. Further, an elastic seal member 14 is provided around the mating surface of the lower mold 1 or the upper mold 3, and when the upper and lower molds 3, 1 are clamped, the elastic seal member 14 is interposed in the mating surface. It is designed to be sealed. In the embodiment of the accompanying drawings, an example of a bath is shown as the container-shaped molded product 5 to be molded. The upper portion of the resin filling cavity 6 is a portion for molding the bottom of the container-shaped molded article 5, and the upper portion of the resin filling cavity 6 is such that the gas vent portion 7 is the uppermost end. It is inclined (for this reason, the upper surface of the convex mold portion 2 and the upper bottom surface of the concave mold portion 4 are both inclined surfaces 11 and 12 which are inclined upward toward the degassing portion 7 side.
Therefore, a container-shaped molded product 5 molded for this reason
By forming a hole in the gas venting portion 7 of the container and providing a drainage hole portion 13 there, the container-shaped molded product 5 is set in a normal use posture (that is, the posture of the molded product 5 is in an upper position). When used in), the drain hole is located at the bottom of the container-shaped molded product 5, and the bottom of the container-shaped molded product 5 is inclined downward toward the drain hole.

In the molding die A having the above-described structure, the resin is filled from the lower resin supply portion 8 to the lower portion of the resin filling space 6 and cast molding is performed. The resin is completely filled in the resin filling space 8 by removing the gas from the portion 7 and sequentially filling the resin. When the resin filling space 6 is filled with the resin from below, the gas rises from the convex mold part 2 surface side to the concave mold part 4 side surface as shown by the arrow B in FIG. 3, and along the concave mold part 4 surface. As a result, there is no fear that gas will accumulate and form cavities on the surface of the convex portion 2 surface, and the inner surface of the container-shaped molded product 5 to be formed (that is, the surface that will be the surface of the product). There will be no fear of nests in the area.

Although an example of a bathtub is shown as the container-shaped molded product 5 in the embodiments of the accompanying drawings, the molded product 5 is not necessarily limited to the bathtub, and if it is a container-shaped molded product, for example, a washbasin,
Various things such as sinks can be considered.

[Advantages of the Invention] According to the present invention, as described above, a convex mold part having an upper part wider than a lower part is projected upward on the upper surface part of the lower mold, and is projected downward on the lower surface part of the upper mold. The resin is filled with resin to form a container-shaped molded product with a convex mold part and a concave mold part by clamping the upper and lower molds by providing a concave mold part that is open in the upper part and the lower part of the upper part is wider than the upper part. Since a space is formed and a gas vent that communicates with the upper part of the resin filling space is provided and a resin supply part that communicates with the lower part of the filling space is provided, the resin is supplied from the resin supply part. In this case, when the gas rises from the bottom to the top, the gas rises from the convex surface to the concave surface and rises along the concave surface. The gas does not accumulate, and no cavity is formed on the inner surface of the container-shaped molded product. As a result, the molded product is defective. Is something that disappears.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, FIG. 2 is a perspective view of the lower mold of the same, FIG. 3 is an explanatory view of the rise of gas in the same, and FIG. 4 is molding by a molding mold of the present invention. FIG. 5 is a sectional view of a conventional molding die, FIG. 6 is an explanatory view of a conventional example in which a gas rises, 1 is a lower die, 2 is a convex portion, 3 is an upper mold, 4 is a concave mold part, 5 is a molded product, 6 is a resin filling space, 7 is a gas vent, and 8 is a resin supply part.

Claims (1)

[Claims] 1. A convex mold part having an upper part that is wider than a lower part protrudes upward from an upper part of a lower mold, and a lower part that is open downward and concave upward in the lower part of the upper mold is an upper part. A concave part that is wider than that is provided, and the upper and lower molds are clamped to form a resin filling cavity for molding a container-shaped molded product with the convex part and the concave part. A molding die apparatus, comprising: a gas vent portion communicating with an upper portion of the void and a resin supply portion communicating with a lower portion of the resin filling void.