JPH0363497B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) This invention relates to blow-molded products such as door trims and body side trims of automobiles.

(Conventional technology) Conventionally, door trims and body side trims were
As shown in the figure, it is manufactured by vacuum forming and compression molding a skin 23 such as cloth or polyvinyl chloride leather on a base material 21 such as hardboard or wood stock through a foam 22 such as urethane, polypropylene, or polyethylene. There is. However, in conventional door trims, it is difficult to process the ends 24a and 24b, which tends to result in poor cutting, peeling of the skin, etc., and the appearance of the ends is often unsatisfactory. Ta.
Moreover, an adhesive is required during manufacturing, and when a non-polar resin material such as polypropylene is used, there is a problem in that the surface layer tends to peel off because the bonding strength of the adhesive to the non-polar material is not very high. or,
The texture of the surface largely depends on the pattern and structure of the skin 23, and there was a problem in partially molding the surface three-dimensionally and with different textures. In other words, the embossed portions 26 have partially different textures due to clipping, high-frequency welding, etc.
Although it is possible to form this, there is a problem in that it is expensive because it is done in post-processing.

(Problems to be Solved by the Invention) This invention solves the problems of conventional blow molded products such as door trims, body side trims, etc., where it is difficult to treat the end portions and a cover member is required during assembly, and the surface has a different texture. This solves the problem of having to perform a post-process in order to form a decorative part.

Structure of the Invention (Means for Solving the Problems) In order to solve the above-mentioned problems, in this invention, a skin is set at a predetermined position of a mold of a blow molding device having a constricted part at the open end. By blow-molding the thermoplastic resin as a base material in this state, a configuration was adopted in which both ends were bent integrally with the skin.

(Function) The blow-molded product of the present invention is produced by blow-molding a thermoplastic resin as a base material with a skin set in a predetermined position of a mold of a blow-molding device having a constricted portion at the open end. Because it is manufactured
Due to the blow pressure during the blow molding, the skin and the thermoplastic resin base material are formed into a shape corresponding to the shape of the cavity surface of the mold, that is, both ends are bent integrally with the skin. and,
During blow molding, the skin is firmly bonded to the thermoplastic resin base material through mechanical anchoring and fusion, so no adhesive is required. In addition, when forming partially different decorative parts on the surface of a blow-molded product, blow molding can be performed with the decorative member set at a predetermined position in the mold, so that the partial decorative parts can be formed at the same time as blow molding. It is formed.

(Example) Next, Examples 1 to 4 embodying this invention will be described.
This will be explained according to the diagram. The door trim body 1 is made of polypropylene, polyethylene,
It is formed from a base material 2 made of thermoplastic resin such as ABS resin and a skin 3 made of cloth, polyvinyl chloride leather, etc. bonded to the surface of the base material 2, and as shown in FIG. It is integrally bent on the inside. In addition, there is a partial decoration part 5 on the surface.
is formed.

Next, a method of manufacturing the door trim constructed as described above will be explained with reference to FIGS. 3 and 4. The blow molding apparatus used in this embodiment differs from a normal blow molding apparatus in that the insides of the left and right pair of symmetrically formed molds 6a and 6b have approximately the same height and width as the molds 6a and 6b. A gas blowing member 7 is provided, which includes an air chamber 7a, a plurality of blowing ports 7b formed on both sides of the air chamber 7a, and a connecting pipe 7c connected to a compressed air source (not shown). Mold 6a, 6
The upper and lower ends of b are bulged inward from each other to form narrowed portions 8a and 8b. Moreover, an extruder 10 is disposed above the gas blowing member 7 for heating and melting the raw material resin of the base material 2 and extruding it as two sheet-like parisons 9.

Now, when molding a door trim using this device, the partial decorative member 11 is set in the molds 6a and 6b as shown in FIG.
A cloth 3a that will become the skin 3 of the door trim body 1 is hung down from above 6b so as to cover the open parts of the molds 6a and 6b. Next, the two sheet-like parisons 9 are extruded by the extruder 10 with the gas blowing member 7 sandwiched between them until the lower ends of each parison 9 reach the lower ends of both the left and right molds 6a, 6b. ,6b
is moved toward the gas blowing member 7 side, and the parison 9 is held between the gas blowing member 7 and both the left and right molds 6a, 6b. Next, each outlet 7b of the gas blowing member 7
Compressed air is blown out from the parison 9 and the parison 9 is expanded.
The parison 9 is then molded into a mold 6a along with the cloth 3a.
It is molded into a shape corresponding to the cavity surface shape of 6b. At this time, the partial decorative part 5 is formed on the surface of the door trim by the partial decorative member 11 set in the molds 6a and 6b. After cooling of the parison 9 is completed, the molds 6a and 6b are opened and the molded products are taken out, thereby obtaining two door trims at the same time. In order to bend both the upper and lower ends 4a, 4b of the door trim inwardly, the open ends of the molds 6a, 6b are provided with a narrowing part 8.
Although the molds 6a and 6b are formed, even if the narrowed portions 8a and 8b exist, due to the shrinkage of the parison 9 as it cools and forced extraction using its elasticity, the molds 6a and 6b are formed.
It is possible to release the molded product from the mold. For example, when polypropylene is used as the thermoplastic resin, its shrinkage rate is 1.5%, so if the height of the door trim is 500 mm, it will shrink by 7.5 mm after cooling is completed, making it possible to release the mold. The door trim is completed by cutting both ends of the molded product taken out at the cutting portions shown by chain lines in FIG. Since the cloth 3a constituting the skin 3 is firmly bonded to the surface of the parison 9 by mechanical anchoring or fusion during blow molding, no adhesive is required.

When forming a simple embossed part as the partial decoration part 5, the partial decoration member 11 having an uneven pattern is used.
When set in the molds 6a, 6b, an embossed part as the partial decoration part 5 is formed by the partial decoration member 11 during blow molding. Also, partial decorative member 1
As 1, a member with a shape whose peripheral edge is widened,
The mold 6 is placed in a state where the expanded part faces the cloth 3a.
a, 9b, an undercut portion will be formed at a portion corresponding to the peripheral edge of the partial decorative member 11 during blow molding, and the partial decorative member 11 will be in a state of being fitted into the undercut portion, and the adhesive will be released. At the very least, it is securely fixed in place.

Note that the present invention is not limited to the above-mentioned embodiments, and for example, the formation of the partial decorative portion 5 may be omitted, the body side trim may be formed instead of the door trim, or the molds 6a and 6b may be asymmetrically formed. The shape, structure, etc. of each part may be modified without departing from the spirit of the invention, such as by employing a conventional extrusion blow molding method, heated sheet blow molding method, or other blow molding method in place of the blow molding method in the examples. It is also possible to change it arbitrarily.

Effects of the Invention As detailed above, according to the present invention, a thermoplastic resin as a base material is blown with a skin set in a predetermined position of a mold of a blow molding device having a constricted part at an open end. By molding, both ends are bent integrally with the skin, so unlike the conventional method, there is no need to use a cover member to hide insufficient end treatment. Additionally, during blow molding, the skins of door trims, body side trims, etc. are firmly bonded to the base material through mechanical anchoring and fusion, which eliminates the need for adhesives, reduces the number of steps, and reduces costs. It has excellent effects.

Further, by arranging the partial decorative member in the mold as in the above embodiment, an excellent effect is achieved in that partial decorative parts having different textures can be produced on the surface of the molded product at the same time as blow molding.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a door trim embodying the present invention, FIG. 2 is a partial sectional view of the door trim body, and FIGS. 3 and 4 are sectional views showing a method of manufacturing the door trim.
FIG. 5 is a perspective view showing a conventional door trim, and FIG. 6 is an enlarged sectional view taken along the line AA in FIG. 5. Door trim body...1, base material...2, skin...3, cloth...3a, end...4a, 4b, partial decorative part...5, mold...6a, 6b, drawing part...8a, 8b.

Claims (1)

[Claims] 1 By blow-molding the thermoplastic resin as the base material 2 with the skin 3 set in the predetermined positions of the molds 6a and 6b of a blow-molding device having constricted parts 8a and 8b at the open ends, both ends are Part is epidermis 3
A blow molded product characterized by being bent and formed integrally with.