JPS60122132A - Manufacture of multi-layer hollow molding - Google Patents

Abstract

PURPOSE:To eliminate the need for cutting off a skin while preventing the cut surface of the skin from exposing to the outside of a product by folding the end rim inside a molding to cover the end face thereof with a parison circular in the section when the skin of the molding is formed into a specified shape by vacuum forming. CONSTITUTION:Soft foamed synthetic resin sheets 21 and 31 undergo a vacuum forming to form skins 23 and 33 of a specified shape having folds 24 and 34 at the end rims thereof. Then, the skins 23 and 33 are mounted on hollow molding dies 41 and 42 and a parison 43 made of a hard synthetic resin circular in the section is introduced to the position where the tip thereof will not come out of the folds 24 and 34. Then, after the clamping of the dies 41 and 42, air is blown into the parison 43 to perform a blow molding. Here, the folds 24 and 32 overlap tight and are expanded so as to be covered with the parison 43 completely.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for manufacturing a multilayer hollow molded article.

[Technical background of the invention and its problems] - For example, in hollow molded products such as automobile console box lids, glove box lids, armrests, or heat insulating ducts, it is important to have flexible feel and strength, or heat insulation and strength. In order to satisfy both requirements, a multilayer structure may be used.

When manufacturing such a multilayer hollow molded product, such as the lid of a console box; conventionally, as shown in Figure 1, a mold 111 for molding
(2) A parison 141 with an annular cross section from the nozzle field in between
Dispense and introduce i51 in double layers inside and outside, and mold (1)
After closing the mold (2), by blowing air into the inner parison (5), the parison +41 (57) is tightly integrated and molded into a predetermined hollow shape as shown in Figure 2, and then, Joining part 16117 at both upper and lower ends
By cutting 1k, a lid (8) as shown in the figure is obtained, and the outer parison 14), which becomes the skin (9) of the lid (8), is made of soft foam synthetic resin
) The inner parison (5), which is the core material □(l), is made of hard synthetic resin to satisfy both soft feel and strength.

In addition, as another manufacturing method, as shown in FIG.
[The skin a3I made of soft foamed synthetic resin with 121 remaining is attached to the mold 11+ (21) for blow molding, and this mold fi
+ (Rate-shaped parison a with core material a5I pattern between 21
After introducing nu and closing the mold 111121, air is blown between the parisons 0908 to mold the parison surface a8 into a predetermined shape and to form the skin [131
(141, and then the epidermis fl: H41
By cutting out the joint part of the core material f151 (161) which is closely integrated with the joint part συ circle and this joint part tIIIl force, the lid shape as shown in Fig. 5 is obtained.

However, in the case of the method shown in Figures 1 to 5, the outer skin +91 and the core material (101 joint part +61
In the case of the method shown in Fig. 5, the surface skin t131 (141 joint part tin
The joining part of the core material 0S field is in a state where the joint part of the mold 111 + 21 comes out on the entire circumference outside, and for this reason, the lid (8) in the opposite figure is at both ends, and the lid (in the figure 5) is 19, all around, as shown in figure 6, 5, epidermis +9) [13+
α4 and core material (11) (The cut surface of
Resection of the joint part +67171 QIJ a'1 was also troublesome.

[Purpose of the invention]

The present invention was made in view of the above-mentioned points, and aims to eliminate the need to remove the epidermis when producing a multilayer hollow molded product, and to prevent the cut surface of the epidermis from being exposed to the outside of the product. That is.

[Summary of the invention]

The present invention is a method for manufacturing a multilayer hollow molded product having a plurality of synthetic resin layers, in which the skin of the molded product is formed into a predetermined shape by vacuum forming, and the edge of the skin is attached to the inner side of the molded product. After forming a folded part toward the above and attaching it to at least one of the hollow molding molds, a parison having an annular cross section is introduced between both molds, and the mold is closed, air is sucked into the parison, and the above-mentioned It is characterized in that the end face of the skin is covered with a parison.

[Embodiments of the invention]

The method for producing a multilayer hollow molded article of the present invention will be explained in detail based on examples shown in the drawings.

Note that this embodiment is an example of manufacturing a lid similar to the lid 181 ([!1) of a console box for an automobile shown in Figures 1 and 5 and Figure 5.

First, as shown in Figures 1 and 7, the rate Cal+ made of soft foamed synthetic resin is plasticized by heating to a temperature above the softening point and below the melting point, and then straight-butt molding is performed using a vacuum forming mold (221). , form the upper surface of the lid into a predetermined shape, and at the edge of the upper surface of the lid, form a folded part (through) toward the inside of the lid over the entire circumference, and remove unnecessary parts 4. By cutting, a predetermined shape of the epidermis (C) with a folded part (to) at the end edge is formed as shown in Figure 8.Also, similarly, as shown in Figures 1 and 9, Vacuum molding mold C321 for sheet G11 of soft foamed synthetic resin board
Vacuum forming is performed to form a predetermined shape such as the skin opening on the lower surface of the lid, and a folded part C (41) directed toward the inside of the lid is formed at the edge of this skin opening all around the circumference, and an unnecessary part C351 is removed. By cutting, a predetermined shape of the epidermis (3:1 ratio) having a folded part 1341 at the end edge, as shown in FIG.

Next, as shown in Figure 11, each of the above-mentioned skin bodies is attached to a hollow molding mold (41) having the same shape as the lid, and a parison ring made of hard synthetic resin and having an annular cross section is inserted between the molds G411G421. is introduced to a position where its tip does not come out from the folded part Cl41 G41 of the epidermis (231c (31) attached to the Kushi I former 43).

The tip of the parison C3 is sealed by the previous mold closing (411f47J), and air is blown into the inside of the parison C3 to the extent that the parts other than the tip are not thermally fused. (It is assumed that the diameter is the same as that of the nozzle (not shown) that discharges 431.

Further, in the upper part of the old mold 421, as shown in FIG.

Next, after closing each of the molds 0 and 421 above,
Blow molding is performed by blowing air into the parison (G) from an air blowing port (not shown).

At this time, each of the above-mentioned molds (each skin c!3CI3 folded L its r24 attached to 411 (42)) CW
As shown in Figure 15, when the mold is closed, they overlap each other and are in close contact with each other inward, and when the parison is expanded by blowing air, the folded part &41c34J in the close contact state is As shown in Figure 16, it is completely covered by the parison (43).

Then, Lord Parison, expanded by blow molding, has a spear.
As shown in Figure 7 and Figure 18, the epidermis c! 3c (the folded part (to) of 3) (2) is wrapped and completely fixed, and the outer skin (c) and the parison (core material T51 made of 41) are used as a multilayer hollow molded product for a console box for an automobile. Ritsu #
I can do t■.

Further, at the upper end of the lid 53, the hinge forming portion -
, the thin-walled hinge Q and the mounting hole (
A mounting piece 69 with 54) is integrally formed.

The lid 52 manufactured from 5KL has a skin (23C) on its outer surface (23C (31), so the edge part is not exposed, so it has a good appearance and feels good to the touch). The core material (51) is also thin Hins ei31
and mounting pieces (to), so these are not visible from the outside when the lid 5z is attached to the console box, and in addition, the skin t'a31+
There is no need to cut off the ends such as 331, and no finishing treatment is required.

In addition, when blow molding the above-mentioned Lord Parison, if the parison (431 and the skin +23C131 are not thermally fused to each other), an adhesive may be applied to the skin c!1c (31) in advance.

Further, in carrying out the present invention, 1, the above-mentioned lid 15
It is not limited to the double structure as shown in 2, but can also be five or more layers, for example, as shown in Fig. 19 and Fig. J'20,
When 1 with an annular cross section is discharged from the nozzle ill in a double layered state, inside and outside, it becomes a hollow molded product with * * ca < cp31 and a layered structure σ consisting of two layers of core material 6 and a temperature of °C. Lid export can be produced, for example, on the epidermis! 31 α arm, outer core material - 1 inner core material - 6! ! By changing the degree of hardness, the surface feel of the lid haze can be made even better.In addition, by changing the material, hardness, etc. of the six layers, it is possible to meet various requirements.

Also, with products such as Lid 15z-, it is not necessarily necessary to have a skin cover on the bottom (S, so 1F?1 figure and spear 2
As shown in Figures 2 and 2, it is also possible to omit the wheat skins in v41 below.

In addition, as illustrated in Figure 22, the folded part of the wheat skin does not need to be located at the joint of the hollow mold UIl+421, and the point is that the folded part is covered by the parison (4:4). Any position is sufficient as long as it is fixed at the position where the mold (411 (42) is fixed).
(The same is true when attaching l, the folded part G! 41 C of each skin ca + cn is in close contact with the mold closing, and the parison (43 + 621 .

The present invention also applies to console box lids (6zIE)
61 or a product that is installed in a cantilevered manner, such as a glove box lid, but with mounting pieces (towards) on both ends.
When applied to products that require a mounting part such as
Place the tip of the parison 431f; 3 I3) into the mold (411
The epidermis attached to +421 (folded part 1 of 231C33)
241 When taken out from C341, parison 14311Gl? is attached to both ends of the product. An attachment part consisting of Q can be formed.

〔Effect of the invention〕

As described above, according to the present invention, when manufacturing a multilayer hollow molded product, a skin is formed with a folded part toward the inside of the molded product at the end edge, and this skin is attached to a blow molding die. However, since I used this mold to blow mold a parison with an annular cross section, I covered the end surface of the skin with a litho.
The edges of the skin are not exposed to the outside of the molded product, and there is no need to remove them. Therefore, it looks good and feels good to the touch. This process is also easy because it can be done only by

[Brief explanation of the drawing]

Figure 1 is a sectional view showing an example of a conventional manufacturing method for a multilayer hollow molded product, Figure 2 is a sectional view of the molded product, and the opposite figure is a perspective view of the completed molded product. t-ζ is a sectional view showing another example of the conventional manufacturing method, FIG. 115 is a perspective view of the completed molded product, and FIG. Figures 7 to 18 show an example of the manufacturing method of the present invention, Figures 7 and 9 are cross-sectional views showing the state of formation of the skin, and Figures 8 and 10 are perspective views of the skin, respectively. , Figure 11 is a sectional view showing the state of hollow molding, Figure 12 is a perspective view of the blow molding die, Figure 15 is a sectional view showing the state of hollow molding, and Figure 15 is a perspective view of the hollow molding die.
Figure 6 is a sectional view showing the state of the skin during blow molding, Figure 17 is a sectional view of the molded product, Figure 18 is a partially enlarged sectional view thereof, and Figures 19 and 20 show other examples. Show, spear 19
The figure is a sectional view showing the state of blow molding, Figure 20 is a partially enlarged sectional view of the molded product, and Figure 21 and Figure 22 are sectional views of the state of blow molding, respectively, showing still other embodiments. . of... epidermis, Q4... folded part, 031... epidermis, C
341...Folded part, 411f43...Blow molding mold, (43...Parison, 53...Glue lid as a molded product, tlJI3...Parison, Trowel...Lid as a molded product.

Claims (1)

[Claims] (11) A method for manufacturing a multilayer hollow molded product having a plurality of synthetic resin layers, comprising: forming a skin of the molded product into a predetermined shape by vacuum forming; A folded part facing the inside of the molded product is formed, this is attached to at least one of the hollow molding molds, a parison with an annular cross section is introduced between both molds, and after the mold is closed, the folded part is inserted into the parison. A method for producing a multilayer hollow molded product, characterized in that air is sucked in and the end surface of the skin is covered with the parison.