JP2002086547A - Manufacturing method for hollow molded article having skin material integrated therewith, and blow mold used therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method for a hollow molded article having a skin material integrated therewith which can fix the skin material without being restricted by an article shape and ensures a stable quality, and a blow mold used therefor. SOLUTION: A cavity surface 11 whereon the skin material 2 is disposed is sandblasted or etched to provide the cavity surface 11 with an indented part 12. By using the blow mold 1 thus prepared, the skin material 2 so molded preliminarily as to be along the cavity surface 11 is pressed against the surface 11 and held thereon. Then, a parison 4 is extruded from a die 3 and mold parts are clamped with the parison 4 held between. Compressed gas is blown thereafter into a parison hollow part S held in a cavity C of the blow mold 1 so as to inflate it and thereby the hollow molded article 6 having the skin material 2 integrated therewith is molded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for blow molding.
The present invention relates to a method for manufacturing a hollow molded article integrally formed with a skin material, in which a skin material provided in a blow mold is integrally adhered, and a blow mold used for the same.

[0002]

2. Description of the Related Art A hollow molded article integrally formed with a skin material on which a decorative skin material is adhered is used for interior parts for vehicles such as armrests. In such products, a skin material is previously arranged on the cavity surface, a parison is sandwiched by a blow mold, the mold is closed, and a hollow molded product integrated with the skin material is formed in a blow molding process. Here, in order to obtain a desired skin material-integrated hollow molded article, the skin material had to be temporarily fixed to the cavity surface before blow molding.
As a method therefor, a method in which needle-like projections are provided in the cavity to fix the skin material (Japanese Patent Application Laid-Open No. H8-323849), and a method in which elastic hook-like hairs are used in place of the needle-like projections (Japanese Patent Application Laid-Open No. H9-239)
Invention technologies such as -11324) have been proposed.

[0003]

However, using the above-mentioned prior art, it was not possible to fix the skin material on the side surface of the product (when the wrapping material was folded). Further, in the related art, since a material different from that of the blow mold is used, there is a possibility that a parting line formed when the mold is attached to the mold may be transferred to a product.

[0004] The present invention solves the above-mentioned problems, and a method of manufacturing a skin-integrated hollow molded article in which a skin material can be fixed to a cavity surface without being restricted by a product shape and the quality is stably ensured. And a blow mold used for the same.

[0005]

In order to achieve the above object,
The gist of the invention described in claim 1 is to use a blow mold in which an uneven surface is provided on the cavity surface by applying a sandblasting process or an etching process to the cavity surface in which the skin material is provided, and follow the cavity surface. Then, the skin material is pressed against the cavity surface to hold it, and then the parison is extruded from the die, the mold is closed with the parison interposed therebetween, and then the compressed gas is blown into the parison hollow portion housed in the blow mold cavity to inflate. And a method of manufacturing a hollow molded article integrally formed with a skin material, comprising forming a hollow molded article in which the skin material is integrated. Here, “holding” of “pressing and holding the skin material against the cavity surface” suffices if the hollow material can be held until it is formed. The gist of the invention described in claim 2 is to use a blow mold in which the cavity surface in which the skin material is provided is subjected to sandblasting or etching, and a concave / convex portion is provided on the cavity surface, and is along the cavity surface. The preformed skin material is pressed against the cavity surface to hold it, and then the parison is extruded from the die, the parison is sandwiched, the mold is closed, and then the compressed gas is blown into the parison hollow portion housed in the blow mold cavity. And inflating the molded product to form a hollow molded product in which the skin material is integrated.

[0006] The gist of the invention according to claim 3 is that an uneven portion formed by sandblasting or etching on the entire cavity surface on which the skin material is provided, and an uneven portion formed above the cavity surface on which the uneven portion is formed. A blow mold, comprising: a hanger for hanging a skin material on a mold surface; a burr of the skin material hung on the hanger; and the skin material can be pressed against a cavity surface and held. It is in. The gist of the invention according to claim 4 is that an uneven portion formed by sandblasting or etching on the entire cavity surface on which the skin material is provided and a mold surface above the cavity surface on which the uneven portion is formed are formed. A blower, comprising: a hanger for hanging a skin material; a burr provided with a preformed skin material, the burr of the skin material is hung on the hanger, and the skin material can be pressed against a cavity surface and held. In the mold.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a method for producing a hollow molded article integral with a skin material of the present invention and a blow mold used therefor will be described in detail. 1 to 6 show a method of manufacturing a skin material-integrated hollow molded article according to the present invention and one embodiment of a blow mold used for the method. FIG. 1 is a partial longitudinal sectional view of the blow mold, and FIG. Enlarged view, FIG. 3 is a partially enlarged view showing a state in which a skin material is held on a cavity surface in a blow mold, FIG. 4 is a longitudinal sectional view showing a state in which the process proceeds from FIG.
FIG. 5 is a longitudinal sectional view showing a state in which the process is further advanced from FIG. 4 and the mold is closed, and FIG. In addition, in order to make the lead line of a code easy to understand in a figure, the cross-section hatching of the skin material 2 and the parison 4 is partially omitted.

(1) Blow Mold for Manufacturing Hollow Molded Product with Skin Material The blow mold 1 used in the method for manufacturing a hollow molded product with a skin material of the present invention is a pair of split dies, and one of the split dies has an uneven portion. 12
And a hanger 19. The uneven portion 12 is schematically shown large in each figure, but is finer than the entire shape of the cavity surface 11. The uneven portion 12 is the skin material 2
Is provided on the cavity surface 11 of the split mold on which the surface is set. The uneven portion 12 is formed by sandblasting or etching over the entire cavity surface 11 on which the skin material 2 is set. The skin material 2 is set on the cavity surface 11 before blow molding, and the hollow molded product 6 is set.
The surface material 2 is integrated when the blow molding is performed. However, the surface material 2 set on the cavity surface 11 may come off or shift in position before blow molding. In the present invention, the skin material 2 is securely held along the cavity surface 11 by forming the uneven portion 12. The skin material 2 made of a fabric or the like is preliminarily formed by hot press molding or the like, but it is difficult to set the skin material 2 on the blow mold 1 along the cavity surface 11. Due to the formation of the uneven portion 12, the skin material 2 is hooked on the protruding end 121, and it is possible to set and hold the skin material 2 until the blow molding is completed. In the present embodiment, since the skin material 2 is only attached to one surface of the hollow molded product 6,
The uneven portion 12 is provided on only one of the pair of split molds.

The uneven portion 12 is preferably subjected to sand blasting from the viewpoint of ease of production and easy holding of the skin material 2. The uneven portion 12 subjected to the sandblasting process is schematically shown in FIG. 2A. When the skin material 2 is pressed against the cavity surface 11, the projection 121 can enter the skin material 2 and stably lock the same. Because it can be.
In the sand blast, since the abrasive material is sprayed on the cavity surface 11 to form the uneven portion 12, the uneven portion 12 with the sharp projection 121 as shown in FIG. When the sandblasting process is performed, a curved concave portion 122 is formed around the pointed protrusion 121 due to collision of the abrasive material with the cavity surface 11.
Therefore, the skin material 2 pressed against the cavity surface 11 easily enters the pointed protrusion 121.

In the etching process, the concave and convex portions 12 are formed while dissolving the cavity surface 11 chemically or electrochemically. Therefore, the uneven portion 12 may stay on the protrusion 121 having the flat portion 123 at the protruding end as shown by the solid line in FIG. In such a case, the retention of the skin material 2 by the projections 121 is somewhat inferior to that of the sandblasted one. However, if the etching process is also performed properly, the shape of the chain line in FIG. 2 (b) and the shape of FIG. 2 (c) will be obtained, and the skin material 2 formed with the pointed protrusion 121 and pressed against the cavity surface 11 will be held by this. Will be done.

The uneven portion 12 can be easily applied not only to the product front surface cavity surface 11a but also to the product side surface cavity surface 11b, regardless of whether it is sandblasting or etching. Therefore, it is not difficult to fix and hold the skin material 2 on the side surface of the product unlike the related art.

The hanging member 19 is a rod-like body having a sharp point, and the mold surface 16 above the cavity surface 11 in which the uneven portion 12 is formed.
Are fixedly installed. Burr margin 2 above skin material main body portion 21 preformed in the shape of cavity surface 11
2 is pierced into the hanger 19 so that the skin material 2 can be hung on the blow mold 1. The shape of the hanging tool 19 is not particularly limited as long as the skin material 2 can be hung from the blow mold 1 in the mold open state so as to hang it.

The other parts of the blow mold 1 are the same as those known in the art, and the cavity surface 11 is closed to form a cavity space of a hollow molded product integrally formed with the skin material. Reference numerals 14 and 15 denote cutout portions, and the above-described hanging tool 19 is provided on the mold surface 16 above the cutout portion 14. Reference numeral 3 denotes a blow molding die (die head) from which the parison 4 is extruded.

(2) Manufacturing method of hollow molded article with skin material The manufacturing method of the hollow molded article with skin material is based on the blow mold 1 described above.
Can be performed, for example, as follows.
First, the skin material 2 is preliminarily formed into a shape conforming to a product (skin material integrated hollow molded product) by hot press molding or the like. By shaping the skin material 2 into a product shape, it is easy to set the skin material 2 on the cavity surface 11, and it is possible to prevent displacement of the skin material 2 by integral molding with the hollow molded product 6.

Next, with the mold open, the skin material 2 shaped in a predetermined shape is pressed against the cavity surface 11 of the blow mold 1 on the side where the concave and convex portions 12 are formed and held. More specifically, a burr 22 at the upper edge of the preformed skin material 2
Is pierced into the hanger 19 and is hung on the hanger 19, and the main body portion of the skin material 2 hanging from the hanger 19 is pressed against the cavity surface 11, and the skin material 2 is placed on the uneven portion 12 formed on the cavity surface 11. Hold (Fig. 3). As the skin material 2, a cloth material such as a fabric skin is used. If the skin material 2 is simply hung on the hanging tool 19 and applied, even if the skin material 2 is shaped so as to follow the cavity surface 11, the skin material 2 can be shaped like the chain line in FIG. Get away from it. The skin material 2 is securely held along the cavity surface 11 by the formation of the concave and convex portions 12. In the case where the skin material 2 is thin, the skin material main body portion 21 may be pressed into the cavity surface to form and hold a predetermined shape. In this case, the sheet-like skin material 2 can be used as it is. The preform of the skin material 2 can be omitted.

It is not necessary to hold the skin material 2 for a long period of time. In the present invention, the skin material 2 is held on the cavity surface 11 during the period from setting of the skin material 2 to the cavity surface 11 to blow molding. If this is the case, it is temporary holding that satisfies the conditions, and the formation of the above-mentioned uneven portion 12 is sufficient. further,
After blow molding the skin-molded one-piece hollow molded product, the skin material 2
Together with the hollow molded article 6 having the
Therefore, the uneven portion 12 of the present invention has a more preferable shape. In addition, since the uneven portion 12 is formed on the entire cavity surface 11 on which the skin material 2 is set, the skin material 2 can be brought into contact with the cavity surface 11 at all locations, and is excellent without wrinkles, misalignment, and the like. Finished product. Needless to say, since the preformed skin material 2 is used, there is little trouble in bringing the skin material into close contact with the cavity surface 11.

Subsequently, the parison 4 is extruded from the die, and the mold is closed with the parison 4 interposed therebetween. A thermoplastic resin heated and melted by an extruder (not shown) is extruded from a die as a cylindrical parison 4. The thermoplastic resin used for blow molding includes low density or high density polyethylene, polypropylene, vinyl chloride resin, PS (polystyrene) resin, PBT resin, PET resin, polycarbonate, polyamide, EVA resin and the like. The parison 4 extruded from the die descends, passes the cavity surface 11 and, when the lower end of the parison 4 reaches a predetermined point (FIG. 4), closes the mold with the parison 4 interposed therebetween (FIG. 5). A cavity C having a shape of a molded product is formed as the mold is closed. The parison 4 is sandwiched between a pair of blow molds 1 to form a sealed parison 4 a having a hollow portion S and is housed in the cavity C. Excess parison 4 is burr 5 at the cutout
Removed as

Thereafter, compressed gas is blown from a blow pin (not shown) into the parison hollow portion S contained in the cavity C. Compressed gas is blown to inflate the parison 4 to form it on the cavity surface 11 to form the hollow molded product 6 integrated with the skin material 2 (FIG. 6). The parison 4 in the cavity C is in a softened state and is formed integrally with the skin material 2 without an adhesive or the like. Since the skin material 2 is held by the cavity surface 11 and set at a predetermined position of the product, the hollow material integrally formed with the skin material is blow-molded without causing molding failure or the like. After making the skin material integrated hollow molded product,
Finally, a cooling and solidifying step is performed. After cooling and solidification, if the mold is removed, the desired hollow molded article integrally formed with the skin material is completed.

(3) Effect According to the method for manufacturing the hollow molded article integrally formed with the skin material and the blow mold 1 used in the method, the concave and convex portions 12 are formed on the cavity surface 11 which is in contact with the skin material 2. Therefore, all portions of the skin material 2 can be held along the cavity surface 11. The skin material 2 is hooked on the projection 121 of the uneven portion 12, and the skin material 2 is
Is securely held. Since the skin material 2 is a cloth-like or fibrous fabric skin, if the skin material 2 is pressed against the cavity surface 11, the protrusion 121 stabs into the skin material 2 and the skin material 2 can be easily held and fixed. Still, the uneven part 1
2 is not a hook-like or hook-like shape that is intricately entangled with and held by the skin material 2, but has only a pointed projection 121 as shown in FIG. Demolding can be performed smoothly. Further, since the skin material 2 such as a fabric skin is relatively light in weight, the skin material 2 can be held by relying only on the concave and convex portions 12, but in the present embodiment, since the hanging member 19 is provided separately, The entire weight of the skin material 2 is received by the hanger 19.
Therefore, since the uneven portion 12 only needs to temporarily hold the skin material 2 on the cavity surface 11, the uneven portion 12 formed by sandblasting or etching is sufficient. Since the skin material 2 is preformed, the skin material 2 is more fitted and held on the cavity surface 11, thereby assisting the holding by the uneven portion 12. Further, in the present invention, the uneven portion 12 can be formed also on the cavity surface 11b on the side surface of the product, so that the entire skin material 2 is in close contact with the cavity surface 11 to produce a skin-molded hollow molded article excellent in quality. it can. The uneven portion 12 is formed by sandblasting or etching, and is formed by shaving or etching the cavity surface 11 with an abrasive or a corrosive agent. Unlike the thing, the parting line does not transfer to the product.

The present invention is not limited to the embodiment described above, but can be variously modified within the scope of the present invention depending on the purpose and application. The shape, size, number, material, and the like of the blow mold 1, the skin material 2, the die 3, the parison 4, the hollow molded product 6, and the like can be appropriately selected according to the application.

[0021]

As described above, the method for producing the hollow molded article integrally formed with the skin material and the blow mold used in the method according to the present invention can stably hold the skin material on the cavity surface until the blow molding without being restricted by the product shape. In addition, since the uneven surface is directly formed on the cavity surface, excellent effects such as obtaining a stable product in terms of quality can be obtained.

[Brief description of the drawings]

FIG. 1 is a partial longitudinal sectional view of a method for producing a skin material-integrated hollow molded product according to the present invention and a blow mold used for the method.

FIG. 2 is an enlarged view of a portion A in FIG.

FIG. 3 is a partially enlarged view showing a state in which a skin material is held on a cavity surface by a blow mold.

FIG. 4 is a longitudinal sectional view showing a state in which the process proceeds from FIG. 3 and the parison descends to a predetermined point.

FIG. 5 is a longitudinal sectional view in which a process further proceeds from FIG. 4 and mold closing is completed.

FIG. 6 is a longitudinal sectional view showing a state in which compressed gas is blown into a parison hollow portion and blow molding is performed integrally with a skin material.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Blow mold 11 Cavity surface 12 Uneven part 19 Hanging equipment 2 Skin material 22 Burr margin 3 Parison S hollow part

Continuation of the front page (72) Inventor Hirojiro Fukuhara 8-1, Tocho, Fujii-cho, Anjo-shi, Aichi Prefecture F-term (reference) 4F202 AD05 AD08 AF01 AG03 AG05 CA15 CB01 CB13 CD24 CD30 CK11 CL01 CQ01 CQ05 4F208 AD05 AD08 AF01 AG03 AG05 LA01 LB01 LB13 LG22 LJ09

Claims (4)

[Claims] 1. A blow mold having a cavity surface provided with an uneven portion by subjecting a cavity surface on which a skin material is provided to sandblasting or etching treatment, and applying the cavity material along the cavity surface. The parison is then pushed out of the die, the parison is extruded, the mold is closed with the parison in between, and then the compressed gas is blown into the parison hollow part housed in the cavity of the blow mold to inflate, and the skin material is integrated. A method for producing a hollow molded article integral with a skin material, comprising molding the hollow molded article. 2. A surface pre-molded along a cavity surface by using a blow mold in which a sand blast treatment or an etching treatment is applied to a cavity surface in which a skin material is provided, and a concave / convex portion is provided on the cavity surface. The material is pressed against the cavity surface to hold it, and then the parison is extruded from the die, the parison is sandwiched, the mold is closed, and then the compressed gas is blown into the parison hollow portion housed in the cavity of the blow mold to inflate the skin. A method of producing a hollow molded article integrally formed with a skin material, comprising forming a hollow molded article obtained by integrating a material. 3. An uneven portion formed by sandblasting or etching on the entire cavity surface on which the skin material is disposed, and a surface material suspending portion on the mold surface above the cavity surface on which the uneven portion is formed. A blow mold, comprising: a hanger; a burr of the skin material hung from the hanger; and the skin material is pressed against the cavity surface to be held. 4. An uneven portion formed by sandblasting or etching on the entire cavity surface on which the skin material is provided, and a surface material suspending portion on the mold surface above the cavity surface on which the uneven portion is formed. A blow mold, wherein a hanger and a burr of a preformed skin material are hung on the hanger and the skin material can be pressed against a cavity surface and held.