JPS6031937A - Manufacture of molding made of synthetic resin - Google Patents

Abstract

PURPOSE:To manufacture extrusion molding molds easily by dividing a core material made of a metallic plate from the position of a stepped section, bringing the core material to a flat state, forming the core material to a deformable shape in the surface and back direction and separating paths for the extrusion molding molds on the inserting port side. CONSTITUTION:A core material is divided in a section corresponding to a stepped section 1C, and formed in two flat core materials 2a, 2b divided and inserted at approximately the centers of a thick section 1A and a thin section 1B. Consequently, the core materials 2a, 2b can be deformed elastically in both directions of the surface and the back, and the core material 2a and the core material 2b guide tapes 3, 4 in the direction of an extruding port while keeping large spaces to the tapes from the upper side and from the lower side respectively. Accordingly, a path for the core material is separated into a path 54a for the core material 2a and a path 54b for the core material 2b, and both paths 54a, 54b can be formed so as to be separated from paths 55, 56 for the tapes 3, for the tapes 3, 4 on the inserting port 51 side.

Description

[Detailed Description of the Invention] This invention provides an extrusion method for synthetic resin moldings,
In particular, the present invention relates to an extrusion method for a molding having a decorative color tape on its surface and a core made of a metal plate inside.

Automobile side moldings, pan moldings, etc. Moldings manufactured using the synthetic +11 fat Kamiyama molding protect the car body from slight contact with curbs, fences, etc., and also provide color tape on the surface to give it a sense of color. It has the function of increasing decoration.

In recent years, there has been an increasing trend in the use of moldings as shown in FIG. 1, for example, in order to enhance their decorativeness. In Fig. 1, M is a molding, 1 is a molding body made of synthetic resin, 2 is a core material made of a metal plate, 3 is a color tape with one side deformed toward the molding body 1, and 4 is the entire molding body facing toward the molding body. This decorative color tape is deformed and formed into an inverted U-shape, and both sides of the tape are embedded in the main body 1. The feature of this molding is that it consists of a thick inner part IA and a thin part IB whose bottom surfaces coincide with each other, and has a step 11c on the surface. In this case, the core material 2 is inserted approximately at the center of the thick inner part IA and the thin part IB, and a step 2C is provided corresponding to the step IC.

The manufacturing method for such a molding involves forming a metal plate into a predetermined cross section by roll forming to form the core material 2, and then inserting the core material 2 together with the color tapes 3 and 4 into a resin extrusion mold. This is a step of coating the surface of the synthetic resin with a color tape 3.4 at the same time as covering it with the synthetic resin. FIG. 2 is a conceptual diagram showing a resin extrusion mold during the above process, and FIG. 3 is a sectional view taken along the line A--A in FIG. 2.

Reference numeral 5 denotes an extrusion mold, in which a core material 2 formed in a predetermined cross section and a color tape 3.4 are inserted into the insertion opening 5 of the extrusion mold 1.
1, enter the extrusion mold 5 through the insertion port 51, and enter the extrusion mold 5 through the passages 54, 55, .
56 and is guided to a resin flow path 53 communicating with an adapter (not shown), and is carried out from the extrusion port 52 of the extrusion mold together with the resin.

However, according to this method of manufacturing synthetic resin moldings, the core material 2 and the tape 3°4 have irregular cross-sections, so they must always maintain a straight state. The material passage 54 and the color tape passages 55 and 56 are formed close to each other on the insertion opening 51 side as well as on the extrusion opening 52 side and are densely packed. As a result, the mold structure becomes complicated, requiring a great deal of labor and cost to manufacture the extrusion mold (and also, due to wear that occurs during long-term use, passages such as passages 54 and 56 do not communicate with each other). In addition, the equipment for feeding the core material 2 and tapes 3 and 4 to the insertion slot 51 side is located close to each other, making it crowded and complicated, and making it easy to break down and repair. There was a drawback that it disappeared.

This invention was made by focusing on these problems, and the core material made of metal plate is separated from the step part, flattened, and deformable in both the front and back directions, and the passage of the extrusion mold is changed. They are separated on the insertion port side.

An embodiment of the method for manufacturing a synthetic resin molding according to the present invention will be described below with reference to FIGS. 4 to 7.

FIG. 4 is a perspective view of a molding obtained by the manufacturing method of the present invention, FIG. 5 is a schematic diagram of an extrusion mold used in the method of the present invention, and FIG. , two flat core members 2a inserted approximately in the center of the thick inner part IA and the thin part IB.

2b. By molding in this way, the core material 2a,
2b can be elastically deformed in both front and back directions, and the core material 2a is guided from the upper side and the core material 2b is guided from the lower side in the direction of the extrusion port 52 while maintaining a large distance from the tape 3.4.

Therefore, as shown in FIGS. 5 and 6, the core material passages are a passage 54a for the core material 2a and a passage 54b for the core material 2b.
The tape 3.4 can be separated from the passages 55, 56 of the tape 3.4 on the insertion opening 51 side. However, the imVPts 54 a, 54 b gradually approach the passages 55, 56 of the tapes 3, 4 on the extrusion side and merge at the extrusion opening, thus forming the passage 54a.

54b is inclined laterally toward the extrusion port.

As described above, according to the present invention, the metal plate core material is made deformable by being divided at locations corresponding to the stepped portions, so that the distance between the mold passage of the core material and the tape passage is adjusted to the insertion opening. The passages can be separated at the sides, making it easier to manufacture the extrusion mold, thereby reducing manufacturing costs, making maintenance of the mold easier, and allowing the passages to communicate with each other. Moreover, the core material and tape feeding device can be installed separately.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a synthetic resin molding obtained by a conventional manufacturing method, FIGS. 2 and 3 are side and front views of an extrusion mold used in the conventional manufacturing method of a synthetic resin molding, and FIG. Fig. 4 is a perspective view of a molding obtained by the method for producing a synthetic resin molding of the present invention, and Figs. It is a side view, a front view, and a top view of a mold. 1... Molding, 2a, 2b... Core material, 3,
4...Tape, 5...Extrusion mold, 51...Insertion port, 52...Exit, 54a. 54b... Core material passage, 55a, 56a... Tape passage. Patent Applicant Hashimoto Forming Industry Co., Ltd. Agent Patent Attorney Jun Miyazono - 7- 1. Indication of the case Relationship with Patent 1 (C) 3 filed on July 29, 1988, Person making the amendment Case A. Address 320m Utoi, Kamiyabe-cho, Totsuka-ku, Yokohama Name: Hashimoto Forming Industry Co., Ltd. I Submitter: Seigo Oki 4, Agent: 102

Claims (1)

[Claims] A synthetic resin molding body consisting of a thick part and a thin part whose bottom surfaces coincide; a decorative tape that is integrated with the surface of the molding body and partially or entirely deformed in the surface direction; and a decorative tape inside the molding body. In the method of manufacturing a synthetic resin molding in which a flat plate-like core material integrated with the core material is extruded from an extrusion mold, the core material is formed from approximately the center of the thick portion and approximately the center of the thin portion. It is composed of two flat core materials inserted independently from each other in the center, and the passage of the decorative tape in the extrusion/small mold is linear toward the extrusion exit direction, and the two core materials At least the passage of the core material facing the decorative tape is separated from the passage of the decorative tape on the insertion opening side and brought close to the passage of the decorative tape at the extrusion exit, and the passage gives elastic deformation to the core material and guides it in the extrusion direction. A method for manufacturing a molding made of synthetic wood III, characterized by: