JPS6241462B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <<Field of the Invention>> The present invention relates to a method of manufacturing an interior part for an automobile, in which a skin material in which a pad material and a skin sheet are laminated in advance is bonded to a core material.

≪Prior art and its problems≫ Automotive interior parts are generally produced by laminating and pasting padding materials and skin sheets onto a core material such as a board or resin board that is trim-cut to match the shape of each part of the vehicle interior. In addition, it is designed to provide cushioning properties and an external shape.

The manufacturing method for this product is (1) setting the pad material and skin sheet on the core material, folding the edge of the skin sheet and gluing it to the back side of the core material, (2) using welder welding instead of adhesion. (3) Applying urethane elastomer as a skin in one mold, setting a core material in the other mold to engage both molds, and recently, There is a wet method in which a foamable resin liquid is interposed between the elastomer coating and the core material, and this is foamed in a mold to integrate the three.

Among these methods, (1) and (2) cannot provide a curved surface in the thickness direction of the product, so the products obtained by methods (1) and (2) are mainly flat. , it does not fit in places with curvature.

In addition, with method (3), although it is possible to form a curved surface according to the shape of the mold surface, when making a part of the product thinner, the elastomer coating and core material in this part must be brought closer together. Since it must be set in the mold, if it is placed too close to this area, the foaming resin liquid will not be able to fully circulate in this area and the strength will not be achieved.Therefore, there is a limit to thinning beyond a certain level, and there is a drawback that it increases the cost. It was hot.

The necessity of providing extremely thin parts in interior parts is due to the necessity of providing extremely thin parts in the parts where various interior parts formed to fit the shape of each part of the car are assembled into the car. Accuracy is required, and on the other hand, since the interior parts themselves are interposed with a pad material (foamed material), the individual dimensional errors vary widely due to this pad material. Of course, the pad material itself is highly elastic and can absorb assembly errors due to its expansion and contraction, but it is not as easy to assemble, and the part where it is joined to the mating part swells excessively, causing wrinkles in the skin and an unsightly appearance. Become.

≪Object of the Invention≫ The method according to the present invention was made in view of the above-mentioned disadvantages, and the object of the present invention is to add a thermoplastic resin sheet (skin layer) to a thermoplastic foam resin sheet (pad material) of a required thickness. The skin material made by pre-laminating the sheets) exhibits the same cushioning properties and appearance as interior parts obtained by conventional methods, and can be molded into the desired curved shape by pressure pressing, and can be partially laminated. Focusing on the fact that it can be made extremely thin, we simplified the process by bonding this skin material to the core material in a mold and molding it into the required curved surface. By partially thinning the parts and the parts where small items are attached, etc., it is possible to improve the assembly accuracy and the appearance.

<<Structure and Effects of the Invention>> In order to achieve the above object, the method for manufacturing an automobile interior part according to the present invention includes a method for manufacturing an automobile interior part according to the present invention, in which a plate-like material is trimmed to the desired external shape of the product and through-holes are formed at appropriate locations. At the same time as applying adhesive to the core material, this core material is set on the mold surface of the lower mold, and then a skin sheet made of thermoplastic resin is laminated in advance to the pad material made of thermoplastic foamed resin, and the required external shape is formed. The trim-cut skin material is positioned and placed on the core material, and then an upper mold having a vacuum suction port that communicates with a vacuum suction device at an appropriate position is pressurized and engaged with the lower side of the skin material to form the skin sheet. While the surface is brought into close contact with the mold surface of the upper mold by suction, the skin material is flexibly deformed in the thickness direction along the mold surface of the upper mold and the mold surface of the lower mold through the through hole of the core material, and It is characterized by the fact that the pad material in the part is crushed to make it thinner.

In other words, in the method according to the present invention, the skin material can be bonded to the core material in the mold and simultaneously formed into the required curved surface, so the process is simpler than the conventional wet method. This makes it possible to reduce the cost by reducing the number of mating points for mating parts,
The pad material at the attachment point for small items is directly crushed and thinned between the upper and lower molds through the through hole provided in the core material, so this thinned part has a high resin density (apparently). There is no problem in terms of strength.

Therefore, automobile interior parts manufactured by this method enjoy the characteristics of products containing pad materials, and are molded with high precision, so they can be assembled into the car interior with high precision and fit easily into mating parts. The assembly is carried out with high precision, and unlike conventional methods, the pad material expands and contracts during assembly, eliminating wrinkles on the surface.
It has various effects such as improved appearance since it does not tighten.

<<Description of Examples>> Hereinafter, specific examples of the present invention will be described in detail.

First, the various materials used in the present invention include a core material, a pad material (foamed resin sheet, hereinafter referred to as pad material) made of thermoplastic foam resin, and a skin sheet (resin sheet, hereinafter referred to as skin sheet) made of thermoplastic resin. ) and an adhesive for bonding the core material and the skin material together.

The material constituting the core material mentioned above is a board material such as hardboard or chipboard, or a plate-shaped composite resin board obtained by adding 50 parts of wood powder as a filler to 50 parts of polyolefin resin, melting it, and then extruding it. , or ABS resin board, etc., as appropriate.

In addition, when the above-mentioned composite resin board, resin board, etc. are used as the core material, it can be molded into the required curved shape compared to plate material, so the curved parts inside the car,
Ideal as a part to be incorporated into a corner part.

Then, these core materials are trimmed into a desired external shape and subjected to each process described below.

The material constituting the pad material in the skin material is a closed-cell foamed resin sheet made of PP, PE, butadiene, etc., and its thickness is set to the thickness required for normal interior parts. In addition, the materials constituting the skin sheet in the skin material mentioned above include PVC,
The sheet is a colored thermoplastic resin sheet such as ABS, and has a suitable drawing pattern formed on its surface, and the skin sheet and pad material can be laminated by conventionally known methods. Then, the skin material laminated in advance in this manner is trim-cut into the desired external shape of the product, like the core material, and subjected to the processing steps described below.

Furthermore, the adhesive can be appropriately selected from materials that are compatible with the core material and the pad material in the skin material.

Next, the specific manufacturing order using each of the above materials will be explained using the drawings.

FIG. 1 schematically shows a molding apparatus used in the present invention, and the apparatus in the figure includes a lower mold 1, an upper mold 3 guided by guide posts 2 erected on the periphery of the lower mold 1, The lifting ram 4 of the upper mold 3 and the upper mold 3 slide sideways when the mold is opened,
It includes upper and lower heating plates 5, 5 facing the lower mold 1, and a vacuum suction device 6 communicating with a vacuum suction port 3b formed in the mold surface 3a of the upper mold 3.

The mold surface 1a of the lower mold 1 is formed into a flat shape, and the mold surface 3a of the upper mold 3 is molded into a desired curved shape, and the thickness of the cavity formed when the two molds 1 and 3 are engaged. is set to be less than the thickness of the core material + skin material.

To explain the molding order using this molding device, (1) First, as shown in FIG.
Apply with a spray gun, etc.

(2) Next, as shown in FIG. 1, the core material is positioned and placed on the lower mold 1 which is in the mold opening stage.

(3) Next, as shown in FIG. 3, the skin material 12 is positioned between the heating plates 5, 5, and held in this position by a clamp device (not shown), etc., and each heating plate 5, 5, the skin material 12 is heated.

In addition, the heating temperature for the skin material 12 is determined by the pad material 12a and the skin sheet 12 constituting the skin material 12.
Set the temperature to be midway between the softening point and melt pour point of b, and plasticize.

(4) After the heating is completed, the heating plate 5 is moved laterally and removed from the mold, and then the skin material 12 is lowered and positioned and placed on the core material 10.

(5) At the same time, drive the ram 4 and engage the upper mold 3 with the lower mold 1 as shown in FIG. At the same time, the skin material 12 is flexibly deformed along the mold surface 3a of the upper mold 3.

(6) If the vacuum suction device 6 is operated up to this stage, as shown in the enlarged view in FIG. Cool and solidify in this state.

Furthermore, in the present application, the skin material 12 is directly pressed by the upper mold 3 and the lower mold 1, as shown in FIGS. This pressing force crushes the bubbles in the pad material 12a and flattens it.

At this time, as shown in FIGS. 5 and 6, the lower mold 1 and the upper mold 3 directly press the skin material 12 from above and below through the through hole 10a formed in the core material 10, so that the pad material 12a It is easily crushed and thinned, and the strength of this thinned portion is strong.

Therefore, in this embodiment, the protruding portion 3 of the upper die 3
c through the through hole 10a of the core material 10 and onto the mold surface 1a of the lower mold 1 to form a recess on the surface of the molded product (see FIG. 5), or
A convex portion 1b is formed on the upper mold 3.
The structure is such that the skin material 12 is pressed between the flat mold surface 3a and the skin material 12 is thinned while keeping the surface smooth (see FIG. 6).

At this stage, the pad materials 12a are in a semi-molten state, that is, their shape is maintained, but they tend to fuse together, so they adhere to each other due to this pressure, and the adhesive 11 leaches out and impregnates this part. Therefore, if the mold is cooled and solidified in this state, the product will have a thinner wall in this area.

(7) After cooling the mold, stop the operation of the vacuum suction device 6 or switch the valve to vent the mold surface 3a of the upper mold 3 to the atmosphere, and then drive the ram 4 again to raise the upper mold 3. A product that is integrated with the core material 10 and has a required curved surface is taken out.

Note that up to the steps (3) to (7) above, each part can be automatically operated in conjunction with timing control or temperature detection of each part.

In addition, in the above embodiment, the upper mold was vacuum-suctioned at the same time as pressurizing the mold, but in this case,
Since the skin sheet is molded completely along the mold surface shape, it is possible to obtain a sharp and accurate shape.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view schematically showing the molding device used in the present invention, Figs. 2 to 4 are explanatory diagrams showing the molding sequence using the same device, and Fig. 5 is the inside of the mold during molding. FIG. 6 is a partially enlarged sectional view of the inside of a mold showing another embodiment of the method of the present invention. 1...Lower mold, 1a...Mold surface, 3...Upper mold, 3a
... Mold surface, 3b ... Vacuum suction port, 6 ... Vacuum suction device, 10 ... Core material, 10a ... Through hole, 11 ...
... Adhesive, 12 ... Skin material, 12a ... Pad material, 12b ... Skin sheet.

Claims (1)

[Claims] 1 Apply adhesive to a plate-shaped core material that has been trimmed to the required external shape of the product and have through holes formed at appropriate locations, and set this core material on the mold surface of the lower mold, and then apply thermoplastic A skin sheet made of thermoplastic resin is laminated in advance to a pad material made of foamed resin, and the skin material trimmed into the desired external shape is positioned and placed on the core material, and then communicated with a vacuum suction device at an appropriate position. An upper mold having a vacuum suction port formed thereon is engaged with the lower side under pressure to bring the surface of the skin sheet into close contact with the mold surface of the upper mold. A method for manufacturing an interior part for an automobile, characterized in that the pad material in required portions is made thinner by flexibly deforming it in the thickness direction along the mold surface of a lower mold having a through hole passed through it, and crushing the pad material in a required part.