JPH06198662A - Urethane foam molding tool - Google Patents

Abstract

PURPOSE:To prevent urethane foam from leaking without providing a neck part to an end of a skin underpart by a method wherein when a suction cup is arranged so that a surface of a turn part of a core part is drawn by suction in parallel contact with a surface of a top force when the core material is sucked to the top force. CONSTITUTION:In an urethane foam molding tool 1 consisting of a pair of top and bottom molding tools wherein a top force 4 has a core material 4 and a bottom force has respectively a skin 6, at least one suction cup for vacuum 5 is provided at a specific position on a bottom surface of the top force 2, and a suction cup 5 is arranged so that a surface of a turn part 4' of the core material 4 is drawn by suction in parallel contact with a surface of the top force 2 when the core material 4 is sucked to the top force 2. Consequently, since the core material 4 is compressed to be fixed to the top force 2 via the skin 6 at the turn part 4' by attracting the core material 4 to the top force 2 with the suction cup 5, urethane foam 7 to be foamed by injecting between the core material 4 and the skin 6 can be prevented from leaking.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a urethane foam molding die, and more particularly to a urethane foam molding die which does not like adhesion of urethane foam on the back side of inserts such as instrument pads, console boxes and door trims of foam moldings for automobile interiors. .

[0002]

2. Description of the Related Art A foam molded article for automobile interiors, such as a door rim, usually has a core material obtained by injection molding a thermoplastic resin such as ABS, PPG, or ASG. The part is formed so as to partially project. Then, urethane foam is laminated over the entire surface of the core material, and further powder slush molding of vinyl chloride resin or the like is further formed on the surface thereof,
Alternatively, a skin material obtained by vacuum forming a sheet material in which an ABS resin and a vinyl chloride resin are mixed is laminated and adhered via an adhesive.

By the way, molding dies for door rims of this type are often designed to have a folded-back portion at the end in the longitudinal direction, and since this folded-back portion has an undercut shape, this type of design The mold for the door rim is virtually incapable of separating the upper and lower molds.

Therefore, in the molding die 11 for an automobile door trim having the design including the folding-back portion 17, as shown in FIG. 3, only the molding portion of the folding-back portion is independently movable from the lower die. When the mold 12 and the lower mold 13 are divided, the upper mold is opened in the arrow direction by using the hinges 15 attached to the upper and lower molds, and then the split mold 14 and the lower mold 1 are separated.
After the split mold 14 was opened by the hinge 16 attached to the No. 3, the door trim product was taken out, and the structure of the split mold was adopted.

[0005]

However, in the foam molding die for door rims as described above, (1) the shoulder portion, and in the case of the terminal under-shape, the under portion die is a split mold (divided) structure. Need to (2) Since the upper mold and the lower mold are opened and closed by a hinge type, and the mold of the under part is formed by the drawing angle of the upper mold, the restriction of the mold shape of the under part is the locus of opening and closing the upper mold. (3) It is impossible to provide an under part on the entire circumference,
After urethane foaming, post-processing such as terminal bending and adhesion is required. (4) Regarding the under-molded portion, since the neck portion of the skin remains, it takes time and effort to trim the skin of this portion after urethane foaming.

In view of the above-mentioned actual situation, the present invention has arrived at the result of earnestly studying in order to cope with the situation, and a part of the structure of the conventional foaming mold is partially modified so that the end of the skin under portion is necked. An object of the present invention is to provide a urethane foam molding die in which leakage of the urethane foam does not occur without providing any portion.

[0007]

To achieve the above object, the present invention is characterized in that a urethane foam molding die comprising a pair of upper and lower molding dies each having a core member in an upper mold and a skin in a lower mold. In the above, at least one vacuum suction cup is provided at a predetermined position on the lower surface of the upper mold, and when the core material is attracted to the upper mold, the suction cup is sucked so that the folded-back surface of the core material and the upper mold surface are in parallel contact with each other. It is a urethane foam molding die arranged.

[0008]

[Function] A urethane foam that is injected between the core material and the skin because the core material is pressed and pressed onto the upper mold through the skin at the folded portion by pulling the core material to the upper mold with a vacuum suction cup It is possible to prevent leakage of the mold, and it is not necessary to use a split mold structure for the lower mold, which can significantly reduce the mold production cost.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a partial cross-sectional view of a shoulder side end of a door trim forming die according to the present invention. In this figure, a door trim molding die 1 is a pair of molding dies including an upper die 2 and a lower die 3, and the upper die 2 is made of ABS resin, P
A core material 4 made of a thermoplastic resin such as PG resin or ASG resin capable of injection molding is provided at a predetermined position of the upper mold,
For example, it is attached to the upper mold surface through vacuum suction cups 5 provided at a total of eight locations, two locations in the longitudinal direction of the door trim and four locations in the width direction. And
A groove 8 communicating with a vacuum device (not shown) provided outside the molding die 1 is engraved in the upper die 2 to which the vacuum suction cup 5 is attached, and is connected to the suction cup 5.

On the other hand, the folded-back portion 4'of the longitudinal end portion of the core material 4 has an undercut shape so that when sucked by the vacuum suction cup 5, the surface of the folded-back portion is parallel to the lower surface of the upper mold. Is formed in. On the other hand, a lower skin 3 is formed by powder slush molding of vinyl chloride or the like, or a vacuum-molded sheet material 6 in which ABS and vinyl chloride are mixed is set on the lower mold side, and then the upper and lower molds are closed. At that time, the core material 4 is arranged so that the gap between the core material 4 and the skin 6 at the folded portion is about 0.5 mm, and then suction is performed. Then, in the meantime, the soft urethane 7 is injected to foam and cure. At this time, the core material 4 is attached to the upper die 2 by a vacuum suction cup with a predetermined suction force, for example, 2 to 4 kg / c.
Since it is attracted by the vacuum force of m ² , the core material 4 is configured to press and press the upper die through the skin 6 at the folded-back portion 4 ′. As a result, it is possible to prevent the urethane from leaking at the folded position when the urethane foam is cured.

Further, in the above embodiment, the surface of the folded-back portion 4'at the end of the core material 4 in the longitudinal direction has a flat surface, but as shown in FIG. 2, the surface of the folded-back portion 4'has a height. You may provide the protrusion 9 of a triangular cross section of about 1 mm. As a matter of course, it is desirable to attach the triangular projections 9 at the same time when the core material 4 is injection molded. The above-mentioned longitudinal direction means the lateral direction in FIG. 1, and the width direction means the direction perpendicular to the lateral direction in FIG.

[0012]

As described above, according to the present invention, the insert is lifted to the upper mold by the suction cup, and the terminal under part is sandwiched between the insert end and the upper mold to clamp the outer skin under part, and the outer under part end is provided with the neck part. It is possible to completely prevent urethane leakage. As a result, it is possible to omit the process of trimming the skin neck, which was required after the conventional urethane foaming process, reduce costs by simplifying the process, and eliminate the urethane removal of urethane foam leakage by attaching the back surface of the insert to void defects due to urethane leakage. It also becomes possible to significantly reduce the loss of urethane raw materials.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a main part of a urethane foam molding die at the time of molding a door trim according to the present invention.

FIG. 2 is a cross-sectional view showing a modified example of the core material at the time of molding a door trim showing another embodiment of the present invention.

FIG. 3 is a view of a conventional urethane foam mold corresponding to FIG. 1.

[Explanation of symbols]

 1 Foaming Mold 2 Upper Mold 3 Lower Mold 4 Core Material 4'Folded End of Core Material 5 Suction Cup 6 Skin 7 Urethane Foam 8 Groove 9 Protrusion

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location B29L 31:58 4F

Claims (2)

[Claims] 1. A urethane foam molding die comprising a pair of upper and lower molding dies each having a core material in an upper mold and a skin in a lower mold, wherein at least one suction cup for vacuum is provided at a predetermined position on the lower surface of the upper mold. The urethane foam molding die is characterized in that a suction cup is arranged so as to draw the surface of the core material in parallel contact with the surface of the upper mold when the upper mold is attracted to the upper mold. 2. The urethane foam molding die according to claim 1, wherein projections having a triangular cross section are provided on the surface of the folded portion of the core material.