JPH0442090Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to an improvement in an apparatus for feeding powdered plastic molding material into a hollow mold.

(Prior art) Conventionally, as one method for manufacturing skin materials such as automobile instrument panel pads, a liquid or powdered plastic molding material is supplied into a heated hollow mold and the molding material is applied to the mold cavity surface. This is called slush molding, in which the mold is continued to be heated after the excess molding material is discharged from the mold to form a molten film of plastic along the mold cavity surface, and then the mold is cooled to solidify the film. law is used. In addition, in recent years, there has been a tendency to use powder materials, which have better fluidity than viscous liquid materials, as molding materials.

(Problems to be Solved by the Invention) By the way, as shown in the perspective view of the molding die of the instrument panel pad, etc., its external shape, especially the opening 11 of the skin material that is the mounting part, is
The shape of b is generally complex, and on the other hand, in order to efficiently supply molding material, especially powder material, to the mold 10b for this skin material, the mold 10b usually has a flange-like flat part following the mold cavity opening 11b. 1
2b is provided, and an opening 21b of a material storage device 20b such as a bucket is formed in the flat portion 12b of the material storage device 20b such that it can be brought into close contact with the material storage device 20b. When supplying the material, as shown in FIG. 4, the mold 10b is closely attached to the bucket 20b containing the powder material 30b, and the mold 10b is turned upside down to place the powder material 30 in the mold cavity 13b.
After supplying the mold 10b, the material 30b is erected again and the excess material 30b is discharged into the bucket 20b, or a rotatable fin (not shown) provided in the bucket when the mold 10b and the bucket 20b are in close contact with each other.
A method has been proposed in which the powder material 30b is blown up to adhere to the mold cavity surface. On the other hand, the mold 10b has a mold cavity 13b.
From the viewpoint of thermal efficiency, it is preferable that only the back side of the mold cavity is selectively heated. Therefore, in order to enable such selective heating, a heating device 14b is provided on the back side of the mold cavity, or a heating device 14b is installed on the back side of the mold cavity, or selective heating is performed using an open flame or the like. Although it is heated, the flange-shaped flat part 12b following the opening of the mold cavity 13b mentioned above is also heated to a considerable extent by electric heating, etc., and powder material adheres to the flat part when powder material is supplied, causing its adhesion. The resulting material will also be partially melted. However, unlike the cavity surface, the material 30b attached to the flat part is unnecessary for the product, and since the flat part is not heated to the molding temperature as described above, the powder material adhering to the flat part is Gelation and bonding between powdered materials are also insufficient, and when the product (molding film) is removed from the mold, it may be torn off from the product, remain attached to the mold, and be mixed into the raw material during subsequent supply of raw materials, etc. There is a considerable amount of loss, and there is a risk that the material may become non-uniform or foreign matter may be mixed in.

(Means for Solving the Problems) Therefore, the present invention attempts to provide a material supply device for powder slush molding that improves the above-mentioned drawbacks, and its gist is A lid body having an opening corresponding to the opening of the mold cavity, preferably such that a space is formed between the lid body and the flange-like flat surface of the mold when the material storage device and the mold are brought into close contact. The main body of the lid is dropped into a material storage device, and the material supply device is covered with a lid having an opening corresponding to the mold cavity erected from the main body.

(Function) As mentioned above, the material supply device of the present invention is constructed by covering a bucket or the like with a lid having an opening approximately equal to the cavity opening of the mold. Since only the necessary and sufficient material is supplied, it is possible to minimize unnecessary parts of the skin material, and the semi-molten state of this part hardly occurs. In addition, when changing the mold and molding an irregularly shaped skin material, this can be done by covering the bucket with a lid having an opening that corresponds to the shape of the mold cavity opening. This makes it possible to form a skin material. Furthermore, in cases where the main body of the lid is dropped into a bucket and a space is provided between the mold and the lid, the contact area between the lid and the mold during material feeding is small, so the lid may become hot. There is no possibility that the powder material in the material storage device will melt.

(Example) The present invention will be explained below based on examples.

FIG. 1 is a cross-sectional view of essential parts of a material supply device and a mold according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing a state in which the device and mold are attached.

The material supply device 40 includes a material storage device 20 such as a bucket and a lid 50, and a material blowing mechanism such as a rotating fin (not shown) is installed in the material storage device 20 as required. The lid body 50 is provided with an opening 51 substantially in the center of its main body, which corresponds to the mold cavity opening 11 of the mold 10 described later, and preferably the opening edge 21 of the material storage device 20.
The lid main body 53 is bent into the material supply device from the peripheral edge 52 that covers the lid main body 53.
It is preferable to form the opening 51 so that the guide wall 54 is erected therefrom. The lid 50 is preferably made of a material having excellent heat resistance and heat insulation properties, such as a thermosetting plastic foam, a steel plate, or a laminate thereof. When it is formed from a laminate, a foam or the like is used as the outer layer and serves as a heat insulating layer. Further, it is preferable that a heat-resistant elastic sealing material 60 made of silicone rubber or the like is applied to the open end of the guide wall 54 so that the lid 50 and the mold 10 are brought into close contact with each other.

Next, the use of the material supply device 40 of the present invention will be explained. Material storage device 20 configured as described above
The lid body 50 is attached as shown in FIG. 2, and the mold 10 having a hollow cavity 13 is further attached on the lid body 50. At this time, the opening 51 of the lid 50 and the opening 11 of the cavity 13 face each other, and the end of the guide wall 54 forming the opening 51 of the lid 50 is adhered to the outer periphery of the cavity opening. Needless to say.

Then, in this deposited state, the powder material 30 is blown up by a material blowing mechanism (not shown) such as a rotating fin provided in the material storage device,
Adhering the material to the surface of the mold cavity 13 through the opening 51 of the lid body 50, or while maintaining the adhering state, the material storage device 20 and the mold 10 are inverted, and the powder material 30 is supplied into the cavity 13,
The powder material 30 is erected again and the excess powder material 30 is returned into the material storage device 20, thereby depositing a predetermined amount of the powder material 30 on the cavity surface. After that, mold 10
separating the material storage device 20 together with the lid body 50 from the
By passing a heating medium through a heating device 14 provided on the outer surface of the mold, for example, a tube disposed in the mold, the adhering material on the cavity surface is completely melted and a predetermined coating is formed. In addition, before attaching the material to the cavity surface, the mold 10 is heated in advance to a predetermined temperature so that the material can be attached. After cooling the mold, the molded coating is removed from the mold to obtain a skin material.

(Effects) As described above, the material supply device of the present invention is made by covering a material storage device such as a bucket with a lid body provided with an opening that substantially matches the opening of the mold cavity, and therefore supplies material to the mold. When doing so, material is supplied only to the cavities necessary for molding the skin material, minimizing unnecessary parts and significantly reducing material loss. Moreover, since the unnecessary part is formed only at the mold cavity opening, the material attached to this part can be completely melted in the same way as the cavity surface, and can be peeled off and molded together with the skin material. Therefore, the risk of unnecessary parts falling into the powder material is almost eliminated. Furthermore, when replacing the mold with one having a different mold cavity, the lid can be replaced with one having a corresponding opening, making it easy to produce a wide variety of products in small quantities. Further, the lid body can be formed from a thermosetting plastic or a laminate of thermosetting plastic and steel plates, etc., and a great practical effect can be achieved with a simple structure.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of the main parts of the material supply device and mold of the present invention, Figure 2 is a cross-section of the mold attached to the material supply device of Figure 1, and Figure 3 is a cross-sectional view of the mold and its cavity. FIG. 4 is a perspective view seen from the opening side, and an enlarged sectional view taken along the line A--A in FIG. Explanation of symbols, 10... Molding mold, 20... Material storage device, 30... Powder material, 40... Material supply device, 50... Lid.

Claims (1)

[Scope of utility model registration request] A material supply device for powder molding, characterized in that a material storage device such as a bucket is covered with a lid having an opening corresponding to a cavity opening of a mold.