JPH028733Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a slush molding mold, and more particularly, to a slush molding mold for manufacturing skin bodies of automobile interior parts such as instrument panels and meter hoods. .

The above slush molding method uses residual heat retained in the mold by heating the powder material filled in the mold in advance, or molds the powder material after filling it with the powder material. By heating, the part of the powder material in contact with the inner surface of the mold is semi-melted, and the powder material is attached to the inner surface of the mold using the adhesiveness generated in the powder material. A portion of the powder material is discharged from the mold, and the powder material still remaining on the inner surface of the mold is removed by heating the mold further to completely melt the powder material, cooling the mold, and removing the remaining powder material from the inner surface of the mold. The process consists of removing the thin layer of film that has adhered to the mold.

When molding the skin of a conventional instrument panel etc. using the slush molding method,
The process of filling a powdered vinyl chloride resin material into a mold obtained by electroforming, heating, cooling, and demolding has been followed, but for example, in the case of the skin of an instrument panel, It is often necessary to create a large space or notch near the center or side edges of the panel due to the installation location or the location of the panel in the vehicle. Powder material for molding also adheres to the inner surface of the mold at areas where the skin is unnecessary, such as spaces and cutouts, and is integrally molded.After the skin is demolded, these unnecessary parts are cut out from the skin. A portion of this cut-off skin was disposed of as waste material. In order to eliminate the labor and material loss of this cutting operation, a pipe is installed in advance on the side of the mold opposite to the cavity in a mold area corresponding to a portion of the skin that is clearly unnecessary. This pipe is used to supply a low-temperature heat medium to the part, and the temperature of the part corresponding to molding that does not require a mold is lowered compared to the necessary part left as a skin body, thereby preventing unnecessary adhesion of powder material. However, in this case, the mold has a complicated piping structure, and if the structure of the mold itself is complicated, it is necessary to be skilled in piping work to clearly distinguish the necessary and unnecessary parts of the skin. This has the drawback of increasing the cost of the product itself.

The present invention improves these points, reduces the amount of molding material used, clarifies the mold cavity surface temperature of the necessary molding portion of the skin body and the unnecessary molding portion, and has a simple structure. A mold for efficient slush molding is provided by dividing the slush into two parts: a necessary molded part of the skin body and an unnecessary molded part that becomes an opening window or notch part of the skin body. The slush molding mold is characterized in that a heat insulating material is attached to the inner surface of the mold corresponding to the position of the unnecessary molding part of the skin body. Next, specific embodiments of the present invention will be described with reference to the accompanying drawings, in which two or three specific examples of a slush molding die for molding the skin of an instrument panel will be described.

Fig. 1 is a perspective view of the slush molding die according to the present invention with the cavity portion turned down, and Fig. 2 is an enlarged sectional view taken along the line A-A in Fig. 1. In the figure, 1 is a This is a mold for slush molding, and is formed by nickel electroforming, aluminum precision casting, mold spraying, etc., and this mold has a cavity 2 having a shape that matches the shape of a predetermined skin body. The opening edge has an outwardly directed flange portion 3.
are integrally formed, and furthermore, the cavity 2 is made up of constituent parts that are in charge of molding a necessary molding equivalent part 4 and an unnecessary molding equivalent part 5 of the skin body. Incidentally, the mold area corresponding to the unnecessary molded portion 5 is shown in FIG. 1 by a group of broken lines.

Generally, unnecessary molded parts of the skin body are molded into cavity 2.
or cavity 2
There is a tendency for the unnecessary parts to be concentrated on the side surfaces of the body, but the location of the unnecessary parts is, of course, greatly influenced and changed depending on the shape of the target skin body.

In the present invention, as shown in FIG. 2, in the mold 1, a thickness of 2 to 4 mm is applied to the electroformed layer on the cavity surface (inner surface) of the mold corresponding to the unnecessary molded part 5 of the predetermined skin body. A heat insulating material 6 is attached by bolts 8 or the like through a heat-resistant silicon layer 7 having a thickness of 2 to 5 mm. The heat insulating material 6 is made of, for example, polyimide resin alone or a laminate of polyimide resin and glass plate, and must be able to sufficiently withstand the melting temperature of the powder molding material, such as vinyl chloride resin powder. It is. Also, a heat-resistant silicon layer 7 interposed between the mold 1 and the heat insulating material 6
is for bringing the heat insulating material 6 into close contact with the electroformed layer on the inner surface of the mold, thereby preventing the powder molding material from entering between the inner surface of the mold and the heat insulating material 6, and also preventing the powder molding material from entering between the mold inner surface and the heat insulating material 6. This prevents the occurrence of burrs. In addition, the presence of the heat-resistant silicon layer 7, which has a thickness comparable to that of the heat insulating material 6, has a remarkable effect on clearly dividing the opening or notch formed on the molded product. There is.

The slush molding mold shown in FIG. 3 is a modification of the present invention, in which a copper pipe is installed on the surface (anti-cavity surface) of the mold 1 located in a portion corresponding to the required molding part 4 of the skin body. 9 is welded to form a fluid supply path for accelerating the heating or cooling operation of the part corresponding to the necessary forming part of the skin body of the mold, and on the other hand, the metal part located in the part corresponding to the unnecessary forming part of the skin body As described above, the heat insulating material 6 is attached to the inner surface of the mold via the heat-resistant silicon layer 7.

When forming, for example, a soft vinyl chloride skin body for an automobile instrument panel pad using a powder material such as vinyl chloride resin using the slush molding die according to the present invention having the above-described structure, first the powder material is molded into a mold. By charging the powder into a mold and using the residual heat of the mold that has been applied in advance, or by heating after filling the powder material, the powder material in contact with the inner surface of the cavity of the mold is semi-molten, thereby reducing stickiness. The derived material is attached to the inner surface of the mold, and then an unnecessary part of the filled powder material is discharged from the mold 1. The powder material located in a layered manner on the surface of the folded insulation material 6 is discharged out of the mold without being semi-molten. After that, the mold is further heated to completely melt the powder remaining on the mold skin surface corresponding to the necessary molding part, and then the mold is cooled and a thin-walled powder is molded on the mold cavity surface. Remove the epidermal body from the mold.

As detailed above, in the present invention, by attaching a heat insulating material to the mold cavity surface at a position corresponding to an unnecessary molded part that becomes a space or notch in the skin, the space or notch in the skin can be The notch is formed in advance, and the powder material filled into the mold does not melt and adhere to the mold in the unnecessary molding portion of the skin body, and in the subsequent discharge process of excess powder material. The powder material in the packed layer on the part is discharged together, so there is no waste of molding material and the amount of molding material used can be reduced, and there are no spaces or cuts in the skin body after demolding. Since the notch is already completely formed, there is no need to remove unnecessary molded parts from the skin, and the mold that achieves this effect is simply a method of attaching heat insulating material to the mold cavity surface. Since the structure is simple and inexpensive, it can greatly contribute to reducing the cost of the product.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the slush mold cavity according to the present invention with it turned down, Fig. 2 is an enlarged sectional view taken along the line A-A in Fig. 1, and Fig. 3 is a diagram showing another embodiment. This figure corresponds to Figure 2. In the figure, 1 is a mold, 2 is a cavity, 4 is a part corresponding to a necessary molding part of the skin body, 5 is a part corresponding to an unnecessary molding part of a skin body, 6 is a heat insulating material, and 7 is a heat-resistant silicone layer.

Claims (1)

[Scope of utility model registration request] For slush molding molds that form necessary molding parts of the skin body and unnecessary molding parts that become openings or notches of the skin body, a heat-resistant silicone layer is interposed on the inner surface of the mold at the parts corresponding to the unnecessary molding parts. A mold for forming a slush, characterized in that at least a heat insulating material is attached.