JPH05305685A - Production of interior component for automobile - Google Patents

Abstract

PURPOSE:To more efficiently produce an interior component for an automobile having design effect not inferior to that of a conventional stitched skin in appearance and excellent in outward appearance and the touch. CONSTITUTION:The desired part of a skin composed of a thermoplastic synthetic resin shaped so as to have the outer surface shape of a product 35 and having a shaped pattern corresponding to the stitched part of a stitched skin preliminarily formed on the surface thereof by a mold is stitched to apply a stitch design 26. Subsequently, the rear of the skin is lined with an air impermeable seal layer 27 over the range containing at least the stitch design 26 and the skin 23 and a core material 24 are set to the inner surfaces of lower and upper molds 28a,28b and, thereafter, a raw solution for semihard polyurethane foam is injected in the molds to be integrally foamed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a product that does not use a conventional sewn skin and has a design similar to that of the outer appearance, that is, an automobile interior part such as an instrument panel, a console box or a door panel. It relates to a method of manufacturing economically.

[0002]

2. Description of the Related Art In recent years, in the field of automobile interior materials, especially when manufacturing instrument panels, console boxes, door panels, seat cushions for seats, etc., a polyurethane foam stock solution has been injected and foamed between a skin and a core material. By adopting a method of obtaining a skin-integrated molded product, the work efficiency is improved. As a skin used at this time, a skin made of vinyl chloride resin having a sewing stitch design on its surface is generally used from the viewpoint of aesthetic design.

In order to manufacture this kind of interior material, a skin forming die 10 is usually used as a pre-process to form the skin 8 by a powder slush molding method as shown in FIG.
Cut the outer skin 8 at the portion where the stitch pattern is to be inserted,
Next, after sewing the cut pieces 12a, 12b, 12c together, a sewing stitch design 16 is applied along the stitched portion 14 of the sewing skin 13, and a sealing tape 17 for sealing is attached to the back surface thereof, which is complicated and costly. Such a skin forming step was necessary. Next, after setting the sewing skin on the inner surface of the lower mold of the foaming mold and the core material on the inner surface of the upper mold respectively, inject the raw material for polyurethane foam onto the skin and close the mold, foam cure and remove the mold. Then trim the burr to make the product. In this case, a vacuum forming method may be used instead of the skin forming by the powder slush forming method.

Still another method is to use a skin forming mold in which a sewing stitch design is transferred and formed at a predetermined position on the inner surface of the mold, and a surface with the stitch design is formed on the surface by the Bowder slush molding method. The skin was set in a foaming mold, and a skin-integrated molded article was produced by the same method as described above.

Each of these conventional methods has the following drawbacks. That is, in the former method using a sewn skin, the outer skin is first molded and then cut, and the cut pieces are sewn together to form a sewn skin, which requires a lot of man-hours and a high manufacturing cost, which is economically disadvantageous. In addition, the back surface of the sewn portion must be lined with a non-breathable sealing layer such as sealing tape for sealing to prevent leakage of the undiluted solution for polyurethane foam, but the seam allowance is not provided at the seam allowance at the sewn portion of the cut piece. Therefore, when a seal tape is applied here, for example, air is likely to accumulate, and if air accumulation occurs at this portion, the surface of the epidermis becomes uneven and looks good, and the touch becomes poor. Also,
When a stitch design is applied by sewing, since the burr corresponding to the seam allowance is folded back and sewn, the thickness of the skin along the sewn portion is partially doubled, and the tactile sensation is changed from other portions. Furthermore, if the product shape becomes complicated, it becomes difficult to sew, and even if it can be sewn, it tends to bend at the sewn part, which makes it difficult to set it in the foam mold, and it is difficult to fit in the mold and It may be a defective product that is misaligned.

On the other hand, the latter method is an economical method because the stitch design is put on the surface simultaneously with the molding of the skin by die molding, which is an economical method, but the unevenness corresponding to the sewing thread is also formed in the shape of the mold. Therefore, there is a drawback that the appearance is poor and the design is inferior when compared with the sewn skin.

[0007]

DISCLOSURE OF THE INVENTION The object of the present invention is to produce a sewn skin that is produced in a shorter process without using the sewn skin that is produced in the complicated and costly process as described above, and further, the conventional sewn skin Another object of the present invention is to provide a method of manufacturing an interior part for an automobile, which has a design quality comparable to, and has an improved appearance and touch.

[0008]

The present invention comprises a thermoplastic synthetic resin formed in advance on a surface of a product by forming a molding pattern corresponding to the sewn portion of a sewn sewn surface on the surface by die molding. A stitch design is formed on a desired portion of the outer skin by using a sewing means, and then a non-breathable seal layer is lined as necessary on at least a range including the stitch design on the back surface of the outer skin, and the outer skin and the core material are The present invention relates to a method for manufacturing an interior part for an automobile, which comprises setting the foam molding die on the inner surface of the lower mold and the inner surface of the upper mold, and then pouring and sealing the raw material solution for polyurethane foam on the back surface of the skin to integrally foam. Here, the product means a product manufactured by injecting and integrally foaming a skin and a foaming plastic such as polyurethane by molding, for example, a product such as an automobile interior part such as an instrument panel, a console box and a door panel. In addition, the shape of the outer surface of the product means that the outer skin is shaped into the shape of an article to be a product as described above.

In carrying out the present invention, FIG.
-As shown in (2), first, an electroforming mold for use in mold forming of the skin is prepared. In the figure, reference numeral 1 is a skin model for producing an electroforming mold 2. This skin model 1 is made in the same shape as a finished product, for example, by sewing cut pieces of a vinyl chloride resin sheet. Then, the skin model 1 is inverted and an electrolytic solution such as nickel is used.
An electroforming mold 2 as shown in (2) is produced. If this method is used, nickel ions can enter even the fine portion of the skin model 1, so that a mold in which the shape of the model surface, particularly the shape of the stitched portion 4 is faithfully transferred can be obtained. At this time, the height of the convex portion of the electroforming mold to which the sewn portion is transferred is 1 to 3 mm.
(Preferably 2 mm). At a height higher than that, the thickness of the skin becomes thin, and the strength of the formed skin cannot be obtained due to tearing, tearing, and the like. On the other hand, if the height is lower than that, the designability of the molding pattern corresponding to the stitched portion of the formed skin becomes poor. Next, the electroforming mold 2 is made of a thermoplastic resin as shown in FIG. 1 (3) by a powder slush molding method or a vacuum molding method using a skin molding die (not shown) having the inner surface layered thereon. The skin 3 is formed. In the figure, reference numeral 5 is a molding pattern formed on the surface of the skin 3 and corresponding to the stitched portion of the skin model.

The thermoplastic synthetic resin used here is not particularly limited, but usually vinyl chloride resin or thermoplastic polyurethane resin is suitable, and powders or sheets of these resins are selectively used depending on the method of forming the skin. .. When the skin is formed by the vacuum forming method, it is desirable to use a vinyl chloride resin sheet as a raw material and use a female scraping method using a female die in order to improve the transferability of details.

A stitch design 6 is put into a desired portion of the skin 3 previously formed by die-molding as described above by using a sewing means, and at least a range including the stitch design 6 on the back surface of the skin is impermeable to air. The sealing layer 7 is lined.
As shown in FIG. 1 (4), this sewing stitch design 6 is usually provided in parallel with both sides along the modeling pattern 5 corresponding to the stitched portion transferred and formed on the surface during skin forming. However, the present invention is not limited to this, and it is possible to design a stitch design having a free shape at a desired position.

The seal layer 7 is applied in order to prevent the undiluted solution for polyurethane foam injected in the next step from leaking from the stitch stitches of the sewing stitch to the surface of the epidermis. Breathable sealing tape is preferably used. As yet another skin forming method,
Using the above-mentioned skin forming mold, after molding the skin of the thermoplastic vinyl chloride resin by the powder slush molding method, further, by pouring the expandable vinyl chloride resin powder into the mold, heat melting, gelation, of the skin By adding a vinyl chloride resin foam layer to the entire back surface (double slash method), it is also possible to prevent leakage of the stock solution.

Then, the skin prepared in the previous step as described above is set on the inner surface of the lower mold of the foaming mold and the core material is set on the inner surface of the upper mold, and the stock solution for polyurethane foam is injected into the mold through the injection nozzle. Then, the mold is closed to complete the foaming reaction, and then the mold is removed, and the burrs are removed to form a skin-integrated molded product.

A molding surface having the same concavo-convex pattern as that of the electroforming mold 2 is formed on the inner surface of the lower mold of the foam molding mold used at this time. Further, the lower mold may be provided with a vacuum suction function in order to support the setting of the epidermis.

As the polyurethane foam stock solution, a polyurethane foam stock solution which is usually called semi-rigid or rigid is used. As a semi-rigid polyurethane foam undiluted solution, a known one can be used. Its properties are a density of about 0.05 to 0.08 g / cm ³ , reactivity is a cream time of 15 ± 10 sec, and a gel time of 50 ± 30 se.
c, the rise time is 75 ± 30 sec, and the position is appropriate.
The core material used here is a known material, for example, metal such as aluminum or iron, ASG resin, PP resin, ABS.
Examples of the molded body include various synthetic resins such as resin and modified PPO resin. As the rigid polyurethane foam undiluted solution, known ones can be used, the characteristics thereof are density of about 0.08 to 0.12 g / cm ³ , the reactivity is cream time 25 ± 10 sec, gel time 50 ±.
30 seconds, rise time 75 ± 30 seconds, proper position. As the reinforcing core material used here, a known material such as a long glass fiber mat which can be impregnated with a urethane foam stock solution can be exemplified.

2 (1)-(6) show a manufacturing process of a console box as an embodiment of the present invention. First, the skin forming die 20 is used to form the skin by the powder slush method. In the figure, 22 is an electroforming mold, 1
Reference numeral 9 is a vinyl chloride resin powder, and 18 is a skin that is being formed on the inner surface of the mold. When the epidermis is formed, it is released from the mold, and as shown in FIG.
As shown in (2), stitch designs 26 are put on both sides along a modeling pattern 25 corresponding to the sewn portion of the sewn skin model formed on the surface thereof by using sewing means, and the sewn stitch design on the back side is formed. The sealing tape 27 for sealing is attached so as to completely cover it. Then this epidermis 23
Is placed on the inner surface 29 of the lower mold 28a of the foam molding die 28 having the same unevenness pattern on the lower mold inner surface 29 as the electric mold 22 by fitting the mutual unevenness and the core material 24 made of ASG resin. After setting on the inner surface 30 of the upper mold 28b,
A semi-rigid polyurethane foam stock solution, which is the polyurethane foam stock solution 32, was injected into the mold from the injection nozzle 31 and foamed and cured to release the mold, and the burrs 34 were trimmed to obtain the desired product 35. FIG. 3 is a perspective view of the completed console box.

FIG. 4 is a perspective view of an automobile door trim manufactured as another embodiment of the present invention. In this example, a rigid urethane foam stock solution was used, and a long glass fiber mat was used as a reinforcing core material.

[0018]

As described above, according to the present invention, when forming a skin, the number of steps is reduced because there is no conventional complicated and costly cutting process and combined sewing process, and a sewing margin is not required. It is possible to suppress the occurrence of defective products due to puddle and warping of molded skin as much as possible, and it is possible to manufacture interior parts for automobiles etc. that have a design that is not inferior to conventional sewn skin and have an improved appearance and feel. The excellent effect of. Needless to say, the present invention can be applied not only to the interior parts for automobiles, but also to the production of other polyurethane skin integral foaming products such as furniture and other molded products. Further, although polyurethane has been described as an example, it goes without saying that the use of a plastic material having the same effect, such as a phenolic foamable plastic, as a material is also included in the technical idea of the present invention.

[0019]

[Brief description of drawings]

FIG. 1 is an explanatory view of a skin forming step in a manufacturing method of the present invention.

FIG. 2 is a schematic view showing a process of manufacturing a console box as an example.

FIG. 3 is a perspective view of a console box manufactured by the process shown in FIG.

FIG. 4 is a perspective view of a door trim manufactured as another embodiment.

FIG. 5 is an explanatory view of a skin forming step in a conventional manufacturing method.

[Explanation of symbols]

1: epidermis model, 2, 22: electroforming template, 3, 8, 18, 2
3: skin, 4, 14: stitched portion, 5, 25: modeling pattern corresponding to stitched portion, 6, 16, 26: stitch design by sewing, 7, 17, 27: non-breathable seal layer (sealing tape), 9, 19: Vinyl chloride resin powder,
10, 20: Skin forming mold, 11, 21: Reservoir box, 12a, 12b, 12c: Cut pieces, 13: Sewing skin, 15: Seam allowance, 24: Core material, 28: Foaming mold, 2
8a: lower mold, 28b: upper mold, 31: injection nozzle, 32:
Stock solution for polyurethane foam, 33: polyurethane foam, 34: burr, 35: product (console box).

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenji Shibayama, No. 3, Ikuyama, Uchikoshi, Miyoshi-cho, Nishikamo-gun, Aichi Prefecture Toyo Tire & Rubber Co., Ltd. Automotive Parts Technology Center (72) Yuji Aoki Nishikamo-gun, Aichi Prefecture 3 Yoshigayama, Uchikoshi, Ikamayama Toyo Tire & Rubber Co., Ltd. Automotive Parts Technology Center

Claims (1)

[Claims] 1. A sewing means is formed in advance on a desired portion of a skin made of a thermoplastic synthetic resin formed on a surface of a product by forming a molding pattern corresponding to a sewn portion of a sewing skin by die molding in advance. To form a stitch design, and then backing a non-breathable seal layer on at least a range including the above stitch pattern on the back surface thereof, the skin and the core material are respectively covered with a lower mold and an upper mold of a foaming mold. A method for manufacturing an automobile interior part, which comprises setting on the inner surface of a mold, and then pouring and sealing the undiluted solution for polyurethane foam onto the back surface of the skin to integrally foam.