JPH0585169A - Vehicle door trim and method for manufacturing the same - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent dents and protrusions on the surface of the door trim and to form a smooth curved surface along the surface of the core material. In a door trim 10 for an automobile provided with a core material 20 made of a hard urethane foam and a skin 40 which is adhered and laminated on a surface side of the core material 20 with a cushion material 30 interposed therebetween, a heat shrinkage rate is used as the skin 40. An olefinic thermoplastic elastomer sheet having a very small value is used. As a result, it is possible to prevent the skin 40 located on the bubbles 20c existing on the uneven curved surface portions 20a and 20b of the door trim 10 from protruding upward or falling into the bubbles 20c.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle door trim and a method for manufacturing the same.

[0002]

2. Description of the Related Art Generally, a vehicle door trim is provided with a core material 2 made of a rigid urethane foam, as shown in FIG. The core material 2 has a cross-sectional shape that is curved in a wave shape from the upper side to the lower side, whereby a smooth concave curved surface portion 2a is provided on the front surface side (right surface side) of the core material 2.
And a convex curved surface portion 2b are formed. The front surface of the core material 2 is covered with a skin 4 having a cushion material 3 laminated on the back surface.
It is exposed inside the room (not shown). A vinyl chloride sheet (hereinafter referred to as a "PVC sheet") suitable for molding is usually used for the skin 4.

The automobile door trim 1 (hereinafter sometimes simply referred to as "door trim") thus constructed is molded by a known molding means (for example, integral foam molding).

[0004]

In the automobile door trim 1 having the above structure, since the PVC sheet is used as the outer skin 4, dents or protrusions are generated on the surface of the outer skin 4 to form a smooth curved surface. There was a drawback that you couldn't.

That is, since the PVC sheet has a large heat shrinkage, it is greatly shrunk by heat during molding. In this case, there is no problem if the entire skin 4 is uniformly adhered to the core material 2, but as shown in FIG. 7, the core material 2 made of rigid urethane foam has bubbles 2c such as voids on its surface. It has occurred. Therefore, the skin 4 located on the bubbles 2c is not fixed to the core material 2. Therefore, when the skin 4 located on the bubble 2c generated in the convex curved surface portion 2b of the core material 2 is thermally contracted, as shown in FIG. 7A, it is arcuate (shown by a chain double-dashed line) before the contraction. ) Was transformed into a chord.
As a result, the skin 4 falls into the bubbles 2c, and a dent is generated on the surface of the skin 4. On the other hand, when the skin 4 located on the bubbles 2c generated in the concave curved surface portion 2a of the core material 2 is thermally contracted,
As shown in FIG. 7 (b), what was in an arc shape (shown by a chain double-dashed line) before contraction is deformed into a chord shape. This allows
The epidermis 4 rises upward, and a protrusion is generated on the surface of the epidermis 4. The present invention has been made against the background of the above-mentioned conventional technical problems, and forms a smooth curved surface along the surface of the core material so that dents and protrusions do not occur on the surface surface of the door trim. An object of the present invention is to provide an automobile door trim and a method for manufacturing the same.

[0006]

In order to achieve the above object, the present invention comprises a core material made of rigid urethane foam,
In an automobile door trim including a skin covering the core material, an olefinic thermoplastic elastomer sheet is used as the skin.

Further, in order to achieve the above object, the present invention, when manufacturing the automobile door trim, includes a vacuum forming lower die having a die surface corresponding to the back surface shape of the door trim, and the surface shape of the door trim. An upper mold for vacuum forming having a mold surface corresponding to the above, and the lower mold is a core material which is foam-molded into a predetermined shape in advance and whose surface is coated with an adhesive. A first step of mounting in a state fitted to the surface, a second step of fixing the heat-softened skin on the surface side of the core material mounted on the lower mold in a stretched state, and the above-mentioned A third step of fitting the mold and the lower mold with the core material and the skin sandwiched, and vacuum suction from the core material side to the skin side to make the surface of the skin the mold surface of the upper mold. And a fourth step of closely contacting with.

[0008]

According to the present invention, an olefinic thermoplastic elastomer sheet is used as the skin. As shown in FIG. 5, this olefin-based thermoplastic elastomer sheet has a remarkably smaller heat shrinkage rate than the PVC sheet. Therefore, after molding, the skin located on the bubbles of the uneven curved surface portion of the core material does not deform in a chord shape. Therefore, it is possible to prevent the occurrence of dents or protrusions on the surface of the outer skin of the door trim.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. Since the entire shape of the vehicle door trim according to the present invention is the same as the conventional one, the description thereof will be omitted.

Reference numerals 20a and 20b in FIGS. 1 (a) and 1 (b)
And 20c are concave curved surface portions 2 of the door trim 1 shown in FIG.
It shows the portions corresponding to a, the convex curved surface portion 2b, and the bubble 2c, respectively. As is clear from these drawings, the vehicle door trim 10 according to the present invention is composed of a core member 20, a cushion member 30, and a skin 40.

Here, as the skin 40, an olefinic thermoplastic elastomer sheet having an extremely low heat shrinkage is used. The thickness of this sheet is 0.3 mm
About 0.8 mm is preferable.

The cushion material 30 is not particularly limited, but it is preferable to use polypropylene foam having a small specific gravity for the purpose of weight reduction.

As a method of manufacturing the automobile door trim 10 having the above-mentioned structure, a method of manufacturing by a male vacuum forming method or a female vacuum forming method can be adopted.
For the reasons described below, the method of manufacturing by the vacuum drawing method is preferably used.

In the automobile door trim 10 having the above-mentioned structure, since the olefinic thermoplastic elastomer sheet having a very small heat shrinkage rate is used as the outer skin 40, the outer skin 4 largely heat shrinks after molding as in the conventional case. There is no such thing. Therefore, the uneven curved surface portion 20 of the core material 20
A skin 40 located on the bubbles 20c generated in a and 20b
However, it does not deform into a chord due to heat contraction. Therefore, no dent or protrusion is generated on the surface of the skin 40 of the door trim 10, and a smooth curved surface can be formed along the surface of the core material 20 (see FIG. 1).

Next, a method of manufacturing an automobile door trim by the above-mentioned female pull vacuum forming method will be described with reference to FIG. First, as shown in FIG. 2 (a), a vacuum forming lower mold 50 having a mold surface 50 a corresponding to the back surface shape of the door trim 10 (back surface shape of the core material 20), and a mold corresponding to the surface shape of the door trim 10. A vacuum forming upper mold 60 having a surface 60a is prepared. Then, the vehicle door trim 1 according to the present invention is obtained by going through the following first to fifth manufacturing steps.
0 is produced.

First step As shown in FIG. 2 (a), a core material 20 (hard urethane foam; density: 0.3) which has been foam-molded into a predetermined shape in advance on a lower mold 50 and has an adhesive S applied on the surface thereof. , Wall thickness of about 4 mm)
The lower surface of the lower mold 50 is mounted with the lower mold 50 being fitted to the mold surface 50a.

Second Step Next, as shown in FIG. 2 (b), a cushion material 30 (polypropylene foam; density 0.034, meat) is provided on the back surface on the front surface side of the core material 20 placed on the lower mold 50. A skin 40 (olefin thermoplastic elastomer sheet; density 0.9, wall thickness 0.5 mm) laminated with a thickness of about 3 mm and softened by a heating device (not shown) is fixed by a clamp 41 in a stretched state. To do.

Third Step Next, as shown in FIGS. 2 (b) and 2 (c), the upper mold 60 is moved downward so that the lower mold 50 is sandwiched between the core material 20 and the skin 40. The mold surface 50a and the mold surface 60a of the upper mold 60 are fitted together. At this time, the back surface of the skin 40 is in close contact with the front surface of the core material 20 via the adhesive S.

Fourth Step Next, as shown in FIG. 2D, the skin 40 is applied from the side of the core 20.
The surface of the skin 40 is brought into close contact with the mold surface 60a of the upper mold 60 by vacuum suction toward the side.

After the fifth step , by cooling and releasing the mold, an automobile door trim 10 as shown in FIG. 1 is obtained.

In the method of manufacturing the automobile door trim 10 described above, the upper mold 60 and the lower mold 50, the core member 20, and the skin 4 are used.
After being fitted in a state of sandwiching 0 and 0, vacuum suction is performed from the core material 20 side toward the skin 40 side, and the surface of the skin 40 is brought into close contact with the mold surface 60a of the upper mold 60 by the suction force. There is. Therefore, the surface of the skin 40 has a shape corresponding to the mold surface 60a of the upper mold 60, and becomes a smooth surface regardless of whether it is located on the bubble 20c.

On the other hand, in the method of manufacturing an automobile door trim by the male vacuum forming method, as shown in FIG. 3, the same process is performed on the front surface side of the core member 20 placed on the lower mold 50 '. After fixing the heat-softened skin 40 with the clamp 41, vacuum suction is performed from the skin 40 side toward the core 20 side, and the back surface of the skin 40 is brought into close contact with the surface of the core 20 via the adhesive S. The back surface of the core member 20 is brought into close contact with the mold surface 50'a of the lower mold 50 '.

Therefore, in the case of male vacuum forming, about 1 is applied from the skin 40 side toward the core 20 side at the time of forming.
A pressure of Kg / cm ² (atmospheric pressure) will be applied. Therefore, as shown in FIG. 4, the skin 40 located on the bubbles 20c generated on the surface of the core material 20 is pushed toward the core material 20 side by the pressure and falls into the bubbles 20c. As a result,
A dent may occur on the surface of the skin 40 of the door trim 10. Therefore, it is concluded that the method of manufacturing the automobile door trim by the female vacuum forming is preferable as described above.

The present invention is not limited to the above embodiments, but can be modified within the scope of the present invention. For example, in the present embodiment, as the method for manufacturing an automobile door trim using the olefinic thermoplastic elastomer sheet as the skin 40, a male vacuum forming method and a female vacuum forming method are taken as examples. It is also possible to employ means (for example, integral foam molding). However, it is preferable to use the female vacuum forming method as described above.

[0025]

EFFECTS OF THE INVENTION Since the present invention is constituted as described above, it is possible to prevent the occurrence of dents or protrusions on the surface of the skin of an automobile door trim, and to form a smooth curved surface along the surface of the core material. The effect that it can be formed is obtained.

[Brief description of drawings]

FIG. 1 is a sectional view of a main part of an automobile door trim according to the present invention, in which (a) is a sectional view of a convex curved surface portion and (b) is a sectional view of a concave curved surface portion.

FIG. 2 is a cross-sectional view showing a method of manufacturing an automobile door trim according to the present invention, in which (a) is a vacuum molding lower die on which a core material having an adhesive applied to the surface thereof is placed. And (b) is a cross-sectional view showing a state in which a heat-softened skin is clamped in a stretched state on the surface side of the core material,
(c) is a cross-sectional view showing a state in which an upper mold for vacuum forming and a lower mold for vacuum forming are fitted with the core material and the skin sandwiched, and (d) is from the core material side to the skin side. FIG. 4 is a cross-sectional view showing a state in which the surface of the skin is brought into close contact with the mold surface of the upper vacuum molding mold by vacuum suction toward.

FIG. 3 is a diagram showing another embodiment of the present invention.

FIG. 4 is a diagram showing another embodiment of the present invention.

FIG. 5 is a diagram showing heat shrinkage characteristics of a PVC sheet and an olefinic thermoplastic elastomer sheet.

FIG. 6 is a vertical sectional view of a conventional automobile door trim.

FIG. 7 is a cross-sectional view of a main part of a conventional automobile door trim, (a) is a cross-sectional view of a convex curved surface portion, and (b) is a cross-sectional view of a concave curved surface portion.

[Explanation of symbols]

 10 Automotive Door Trim 20 Core Material 40 Skin (Olefinic Thermoplastic Elastomer Sheet) 50 Vacuum Molding Lower Mold 50a Mold Surface 60 Vacuum Molding Upper Mold 60a Mold Surface S Adhesive

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Claims (2)

[Claims] 1. A core material made of rigid urethane foam,
An automobile door trim having a skin covering the core material, wherein an olefinic thermoplastic elastomer sheet is used as the skin. 2. When manufacturing an automobile door trim according to claim 1, a vacuum forming lower mold having a mold surface corresponding to a back surface shape of the door trim, and a vacuum having a mold surface corresponding to a surface shape of the door trim. An upper mold for molding is prepared, and (a) a core material that has been foam-molded into a predetermined shape in advance in the lower mold and has an adhesive applied to the front surface, and the back surface side is fitted to the mold surface of the lower mold. The first step of placing in a state of (2), (b) the surface side of the core material placed in the lower mold, the second step of fixing the heat-softened skin in a stretched state, (c) the A third step of fitting the upper mold and the lower mold with the core material and the skin sandwiched, and (d) vacuum suction from the core material side to the skin side, so that the surface of the skin is the top surface. A method of manufacturing an automobile door trim, comprising: a fourth step of bringing the mold surface into close contact with the mold surface.