JPS6235891B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for molding a long resin article, for example, a long article such as a side molding for a vehicle, and more particularly to a method for molding a long resin article whose cross section is not constant.

For example, in order to manufacture a long side molding whose width gradually becomes narrower toward one end as shown in FIG. 1, injection molding, extrusion molding,
A compression molding method can be considered, but in the injection molding method, it is necessary to cut out the back surface to prevent so-called sink marks on the exterior, so the adhesive area becomes smaller and it is easier to peel off than a vehicle body panel. Furthermore, the extrusion molding method is effective only for molding moldings with a constant cross section, and the compression molding method has the disadvantage of poor productivity and mass production.

The object of the present invention is to eliminate the above-mentioned drawbacks by forming a resin molded article by extrusion molding and press-molding the resin molded article to form a long resin article with an uneven cross section. This will be explained in detail below using examples.

FIG. 2 is a simplified configuration diagram showing an embodiment of the method for molding a long resin article according to the present invention. In the figure, 1 is an extruder, 2 is an extrusion mold, and in the present invention, As shown, a hollow part 3 having a constant cross section and extending in the longitudinal direction from the extrusion die 2 is formed.
An extrusion molded product 4 having the following is manufactured. The molded product 4 may have a circular or rectangular cross-sectional shape. Next, as shown in FIG. 4, this molded product 4, which is still in a softened state, is placed on the upper part of the fixed mold 6 constituting the press molding mold 5, and the molded product 4 is placed on the molding surface 8 of the movable mold 7. Press the molded product 4. in this case,
The width of the molding surface surrounding space 9 obtained by the molding surface 8 is wider than that of the molded product 4, and the thickness is thinner than that of the molded product 4.
Furthermore, since the volume is set to be slightly smaller than the volume of the molded product 4 (excluding the hollow part 3), the inner wall ₄₁ side of the molded product 4 escapes toward the hollow part 3 during the pressing process, so it is difficult to press. Does not require much force,
Further, since the resin of the molded product 4 itself is compressed, the molded product 4 has the same outer shape as the space 9 surrounded by the molding surface 8, and has a minute hollow portion inside.
Therefore, by making the space 9 narrower in the longitudinal direction toward one end, a molding having the shape shown in FIG. 1 can be obtained. In addition, the 6th
By forming a small gap 10 between the fixed mold 6 and the movable mold 7 as shown in the figure,
During the pressing process, the resin of molded product 4 is pressed into this gap 10.
Since it can also be released, molding can be performed well. However, the resin that escaped into the gap 10 will be removed in a later process.

Next, the apparatus for molding a long resin article of the present invention will be explained using FIG. 7. In the same figure,
1 is an extruder, 2 is an extrusion mold, and 11 is a rail for guiding two molding molds 5, and is positioned perpendicular to the molded product 4 extruded from the extrusion mold 2. The molding die 5 has the molding surface 8 explained in FIG. Thereafter, they move to opposite sides and process the molded product 4 to produce a molding of a predetermined length. According to such a device, mass production of moldings becomes possible.

As explained above, according to the present invention, there is a step of obtaining a long synthetic resin molded product having a predetermined width, thickness, and hollow portion by extrusion molding, and a long synthetic resin molded product having a constant cross section, and A press molding mold for a synthetic resin molded product, which is made of a movable mold and a fixed mold, and has a molding surface surrounding space that is wider than a predetermined width, thinner than a predetermined thickness, and has a volume that is slightly smaller than or the same as the volume of the resin. The synthetic resin molded product is compressed to crush the hollow part and fill the surrounding space with resin, so it is possible to create a long resin product with a different cross-sectional shape in the longitudinal direction. Moreover, since the bottom surface of the long object obtained by the method of the present invention can be flattened, a wide bonding area can be obtained, and unlike the compression molding method, expensive molding molds are not required. will no longer be needed.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an example of the side molding, FIGS. 2 to 5 are simplified configuration diagrams showing one embodiment of the side molding according to the present invention, and FIG. 6 is another embodiment of the side molding according to the present invention. 7th cross-sectional view showing
The figure is a simplified configuration diagram showing an embodiment of a molding apparatus for a long resin article. DESCRIPTION OF SYMBOLS 1... Extruder, 2... Extrusion mold, 3... Hollow part, 4... Resin molded product, 5... Press molding die, 8... Molding surface, 9... Space, 10... Gap.

Claims (1)

[Claims] 1. A step of obtaining a long synthetic resin molded product having a predetermined width, thickness, and hollow portion by extrusion molding, and a synthetic resin molded product that is still in a softened state immediately after extrusion molding. sandwiched between a press molding die consisting of a movable die and a fixed die, which have a molding surface surrounding space that is wider than the predetermined width and thinner than the predetermined thickness, and has a volume that is slightly smaller than or the same as the resin volume. 1. A method for molding a long resin article, the method comprising: compressing a synthetic resin molded article to crush a hollow part and filling the surrounding space with resin. 2. The method for molding a long resin article according to claim 1, wherein a concave gap is provided on the wall of the space surrounding the molding surface of the press molding die. 3. A method for molding a long resin article according to claim 1, wherein the outer shape of the space surrounding the molding surface of the press molding die is varied in the longitudinal direction.