JP2960113B2 - Terminal treatment method in flow stamping molding - Google Patents

Description

The present invention relates to a terminal processing method in flow stamping molding.

[Prior Art] Conventionally, there is a flow stamping molding method as a means for obtaining a skin-applied resin molded product (hereinafter simply referred to as a molded product) such as a trim board. As shown in FIG. 8, this molding method employs a convex lower mold 41 in which the outer peripheral side of a molding surface 42 is formed as a step 43, and an upper mold 47 having a protrusion 49 inserted into the step 43 on the outer periphery. Is used. The upper die 49 is disposed above the lower die 41 and can be lowered. A clamp 44 held by a spring 45 is disposed on the step 43 of the lower die 41, and a skin 46 is set between the lower die 41 and the upper die 47 while being supported by the clamp 44. In this state, a molten resin (hereinafter, also simply referred to as resin) 50 is supplied to the molding surface 42 of the lower mold 41, the upper mold 47 is lowered, and skin molding and resin molding are performed between the molding surfaces 42 and 48 of both molds. Perform at the same time. At the time of molding, as shown in FIG. 9, the shallow edge 51 into which the step 43 and the projection 49 are inserted has a narrow clearance W for strongly compressing the thickness of the skin 46 so that the molten resin 50 does not flow out of the mold. Is done. The demolded molded body 53
It has the terminal shape shown in FIG. 10, and has a structure in which the skin 46 covers the cured resin layer 50A. Immediately after removal from the mold, the surplus portion of the terminal skin 46
B is cut at the cutting portion 54 in FIG. 10 to obtain a terminal-shaped product 55 in which the end of the cured resin layer 50A is covered with the skin portion 46A as shown in FIG.

[Problems to be Solved by the Invention] However, in order to obtain the terminal-shaped product 55 shown in FIG. 11, the skin portion 46A of the terminal portion and the resin 50 need to be mixed and solidified. If the solidification of this portion is not sufficient, the skin portion 46A covering the terminal portion of the cured resin layer 50 opens as in a product 55 shown in FIG.

Therefore, an object of the present invention is to provide a molding process for obtaining a skin-pasted resin molded body such as a trim boat, in which the molten resin is sufficiently mixed with the skin and solidified, and does not cause opening or peeling of the skin end portion when the product is formed. An object of the present invention is to provide a method of processing a terminal portion in stamping molding.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a lower mold in which an outer peripheral portion of a molding surface is an upright surface or a tapered side surface,
An upper skin that is large enough to cover the molding surface and side surfaces of the lower die is supported between the lower die and the upper die that is inserted into the lower die in a fitting manner and is pressed against the lower die. After supplying the molten resin to the molding surface of the mold, the lower and upper dies are pressed together, the skin is sandwiched between the shading edges of the lower and side surfaces, and the molten resin and the skin are simultaneously molded on the molding surface. Then, in flow stamping molding for molding a skin-applied resin molded body in which a terminal portion is covered with a skin, the shear edge sandwiching the skin has a first shear edge portion with a wide clearance through which the molten resin flows, and a molten resin positioned below the first shear edge portion. Is formed as a second shear edge portion having a narrow clearance that does not allow outflow.

[Operation] When the lower mold and the upper mold are pressed, the end portion of the skin is sandwiched between the first shear edge portion and the second shear edge portion. The first shear edge portion allows the molten resin to flow out, so that the resin mixes with the skin. The second shear edge stops the flow of the molten resin. By pressing the both molds, a skin-applied resin molded body in which the terminal portion is covered with a skin is formed.

Next, an embodiment of the present invention will be described with reference to FIGS.

FIG. 2 shows an initial step of flow stamping molding. The skin 11 is supported by the support means 9 between the lower mold 1 and the upper mold 15 disposed above the lower mold 1. The upper surface of the lower mold 1 is formed as a molding surface 2, and the outer peripheral portion of the molding surface 2 is formed in a stepped shape protruding outward. A surface 6 is provided. The support means 9 for the skin 11 is attached to the support surface 6. In the support means 9 of this embodiment, a clamp for pinning the skin 11 is fixed on a spring 10 which contracts downward.

The skin 11 is made of a sheet material of a material into which the molten resin is mixed. In this example, on the back of the polyvinyl chloride sheet 12,
A multilayer sheet in which a cushion layer 13 made of a polypropylene foam is laminated is used. The upper die 15 is supported so as to be able to ascend and descend so that the upper die 15 can be inserted into the lower die 1 in a fitted state with the outer skin 11 interposed therebetween and pressed. That is, the upper mold 15 has a molding surface 16 corresponding to the molding surface 2 of the lower mold 1, and the periphery of the molding surface 16 is formed as a protruding portion 17 protruding downward,
The inner surface of the protruding portion 17 is formed in a step shape, and a first upright surface 18, a step portion 19, and a second upright surface 20 are provided. The lower surface of the projection 17 is horizontal, and when the upper mold 15 is lowered, the lower surface of the protrusion 17 comes into contact with the skin 11 supported by the support means 9 and serves as a pressing surface 21 for pressing down the spring 1.

As shown in FIG. 3, the lower mold 1 and the upper mold 15 are used to form a resin molding S with the skin 11 sandwiched between the molding surface 16 of the upper mold 15 and the molding surface 2 of the lower mold 1. Then, the upper die 15 is pressed to a predetermined lowering position L1 so as to have a predetermined interval between the molding surfaces 2 and 16. At the time of pressing, the protruding portion 17 of the upper mold 15 is inserted into the outer peripheral portion of the lower mold 1 with the outer skin 11 interposed therebetween. As shown in FIG. 3, a portion where the skin is sandwiched between the first upright surface 3 of the lower die 1 and the first upright surface 18 of the upper die 15, that is, the first shear edge portion 23 has a wide clearance W1.
The skin 11 is loosely sandwiched to such an extent that the molten resin 21 supplied to the molding part S flows down. The skin sandwiching portion between the second upright surface 5 of the lower die 1 and the second upright surface 20 of the upper die 15, that is, the second shearing edge portion 25 has a narrow clearance W2,
The molten resin 22 is prevented from flowing by strongly sandwiching the skin 11.
A predetermined gap 24 is provided between the two step portions 4 and 19 of the lower mold 1 and the upper mold 15 so that the skin 11 is free in the gap 24 and the dropped molten resin 22 is stored in this portion. It has become.

 Reference numeral 7 denotes a gate for supplying a molten resin to the molding surface 2.

The molten resin 22 such as polypropylene is supplied to the molding surface 2 from the gate 7 (see FIG. 2).
Lower 15 The descending upper mold 15 lowers the spring 10 to a predetermined position L1 via the skin 11 supported by the support means 9, and the two molds are pressed together with the skin 11 sandwiched between the lower mold 1 and the upper mold 15. (See FIG. 1). A predetermined molded portion S is formed by pressing, and the first shear edge portion 23, the gap portion 24, and the second
The shear edge portion 25 is formed. For this reason, as shown in FIG. 1, while the molten resin 22 is filled in the molding portion S,
A part of the resin 22 of the molded portion S flows down from the first shearing edge portion 23 and is stored in the gap portion 24. The second shear edge 25 is the skin 11
, The resin 22 stored in the gap portion 24 does not escape from the mold. When flowing down the first shear edge portion 23, the resin 22
Is sufficiently mixed with the cushion layer 13 of the skin 11 in this portion.

Thereafter, the upper mold 15 is raised to the original position, the mold is removed from the lower mold 1, and the molded body 27 having the cured resin layer 22A shown in FIG.
I got The portion of the molded body 27 corresponding to the first shearing edge portion 23 was in a good solid state because the resin 22 was sufficiently mixed in the skin 11. The surplus portion 27B on the outer periphery of the skin 11 is
The product of the door trim 29 of FIG. 5 was obtained by cutting and removing at the cutting section 28 of FIG. The door trim 29 had a good finish in which the skin portion 27A (see FIGS. 4 and 5) covering the terminal portion was sufficiently hardened and did not open or peel off.

In this embodiment, the lower mold 1 having the gate 7 is used to supply the resin from the gate 7 to the molding surface 2. However, when using the lower mold 31 having no gate 7 as shown in FIG. Lower mold
The resin 22 may be supplied directly onto the molding surface 2 of the 31.

In the present embodiment, the gap portion 24 is formed by the two step portions 4 and 19 at the time of pressing, but the gap portion 24 formed by the both step portions 4 and 19 is omitted, and the first shear edge portion is formed. A configuration in which a structure in which the second shear edge portion 25 is connected to the 23 may be formed (not shown).

Although the shear edges 23 and 25 in this example are both formed by the corresponding upright surfaces, the shear edge is not limited to this, and may be a shear edge composed of tapered side surfaces. (Not shown).

[Effects of the Invention] In the present invention, since the lower mold and the upper mold are pressed and molded, the skin molding and the resin molding can be simultaneously performed, and a skin-pasted resin molded article in which the terminal portion is covered with the skin can be obtained. In the present invention, since the molten resin is allowed to flow out of the first shearing edge portion during molding, the resin can be sufficiently mixed with the skin, and the skin can be solidified satisfactorily. In the present invention, the molten resin that has flowed out at the first shearing edge is stopped at the second shearing edge, so that the resin is prevented from flowing out of the mold.

Thus, in the skin-applied resin molded product obtained according to the present invention, the terminal portion of the skin covering the resin molded product is solidified with the impregnated resin, so that the skin terminal portion does not open or peel off.

[Brief description of the drawings]

1 to 7 relate to an embodiment of the present invention, FIG. 1 is an enlarged view of a molding process mainly using a terminal portion, FIG. 2 is a schematic diagram of a flow stamping mold, and FIG. Fig. 4 is an end structural view of the molded body removed from the mold, Fig. 5 is a perspective view of the molded trim board, and Fig. 6 is a view taken along line VI-VI in Fig. 5. FIG. 7 is an enlarged cross-sectional view, and FIG. 7 is a schematic view of a flow stamping mold using a lower die of another example. 8 to 12 relate to a conventional example, FIG. 8 is a schematic view of a conventional flow stamping mold, FIG. 9 is an enlarged view of a molding process mainly for a terminal portion, and FIG. FIG. 11 is a structural diagram of the end portion of the molded product, FIG.
The figure is a diagram showing a state in which the molded body terminal portion is not defective. 1,31 Lower mold 2,16 Molding surface 9 Support means 11 Skin 15 Upper mold 22 Molten resin 23 First shear edge 25 Second shear edge 27 Mold W1, W2 …… Clearance S …… Molded part

Claims (1)

(57) [Claims] 1. A lower die having an outer peripheral surface formed by an upright surface or a tapered side surface, and an upper die which is disposed above the lower die and inserted into the lower die so as to be fitted and pressed. In between, supporting the skin of the size covering the molding surface and side surface of the lower mold, after supplying the molten resin to the molding surface of the lower mold, press-clamp the lower mold and the upper mold, In the flow stamping mold molding, the skin is sandwiched between the side edge of the upper mold and the inner surface of the upper mold, and the molten resin and the skin are simultaneously molded on the molding surface, and the terminal portion is covered with the skin. A terminal portion in the flow stamping molding, characterized in that the shearing edge sandwiching the first and second shearing edges is a first shearing edge portion having a wide clearance through which the molten resin flows out and a second shearing edge portion having a narrow clearance positioned below the first shearing edge portion so that the molten resin does not flow out. place Method.