JPH10217255A - Mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the forming mold of a skin, in which the pasting of a sealing tape for preventing a foaming material from leaking, by a method wherein guide plates for guiding and forming excess skin developed from some parts of the skin are provided in the neighborhood of the corner parts of the mold and each guide plate is provided at a position a little lower from the apex part of the corner of the mold. SOLUTION: First of all, a heated and softened skin 1 is pressed against the forming part 2a of a mold 22 and attached to the forming mold 22 by being sucked through small holes 2f. In succession, the skin 1 is cooled and stripped from a mold s as to obtain a formed skin 24. At this time, excess films are formed in bridge through guide plates 23 in the same shape at the same position as those of the guide plate. Since the guide plate 23 is provided in the fashion of a thin plate, the portion ranging from the apex part 2c of the corner and the neighborhood of the trim line 2d of a product of which is lacked, when excess skins are guidingly attached under tension, small bridge-like parts develop at the lacked parts 23a, resulting in fusion-welding the skins. Accordingly, the lacked part 23a of the guide plate 23 can be turned into a skin fusion-welded part 26a, at which the skins are fusion-welded without gap between them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding die for heat-softening a sheet-like skin made of a thermoplastic plastic and press-forming the same toward a convex molding portion.

[0002]

2. Description of the Related Art FIGS.
Is disclosed.

FIG. 3 shows a mold according to the prior art and a molded skin formed from the skin via the mold.

First, the molding die 2 will be described. The molding die 2 is formed by assembling a convex molding portion 2a above a trim wire 2d as a product part and a base plate 2e into one body. Further, the molding die 2 is provided with a large number of small holes 2 f at appropriate positions to serve as suction holes for the skin 1.

In order to form the skin 1 using such a molding die 2, the skin 1 is heated and softened, pressed against the molding die 2, and evacuated (using compressed air or a combination of compressed air and vacuum). Then, the skin 1 is formed so as to closely adhere along the molded portion 2a. Then, it is cooled and shape-retained, and the mold is removed to obtain a molded skin 4.

At the time of this molding, the convex molding portion 2 of the molding die 2 is formed.
At the corner 2b where the sides of a intersect, there is a surplus in the epidermis 1,
A molded skin 4 having an overlapped portion generally called a bridge 6 is formed in which this surplus skin is substantially triangularly overlapped so as to bridge from the corner top 2c to the base plate 2e.

As shown in FIG. 4, foam molding 13 is performed by inserting the molded skin 4 into a foaming mold 12 and injecting an appropriate amount of foaming material 13 into a cavity mold 7 from a mixing head 11 to form a core mold 8. Clamp in the direction of arrow P. In the foamed mold 12 which has been clamped, the foaming reaction immediately proceeds and expands to fill the foamed mold 12. When this reaction is completed, the core material 9 and the molded skin 4 are integrally formed via the foam material 13.

As shown in FIG. 5, the molded skin 4 is inserted into the foam molding die 12 by providing a cavity 6 with a recess 6a in the form of a bridge 6 in the cavity mold 7. The sealing tape 5 is stuck on the inner surface side of the bridge 6 (the back surface side of the molding skin) of the molded skin 4 inserted.

Further, a sealing material 10 is provided around the core material 9 and, when the mold is clamped, the sealing material 10 is brought into contact with the sealing tape 5 so that there is no gap where the foaming material 13 leaks, and foaming is performed.

[0010]

However, in the molding die 2 described above, the skin of the bridge 6 formed at the corner 2b at the time of molding is in a state in which there is a gap that has not been fused while being removed from the guide plate 23. In this state, the foam material 1 during foam molding is used.
3 has entered and caused leakage, so that there was a problem that it was necessary to attach the seal tape 5 with extra steps to prevent the foam material 13 from entering.

An object of the present invention is to provide a mold for forming a skin in which a sealing tape for preventing leakage of a foam material can be omitted, in order to solve the above-mentioned problems of the prior art.

[0012]

Means for Solving the Problems In order to achieve the above object, the invention according to claim 1 is to provide a sheet-shaped skin made of a thermoplastic plastic, which is heated and softened to a convex molded portion. In a molding die which is formed into a skin along the molding by pressing toward the molding part, a guide plate is provided near the corner of the molding part for induction molding of a part of the remaining skin of the skin, and the guidance plate is It is characterized in that the surplus skin is guided from a position slightly lower than the top of the corner of the molded part.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is an explanatory view showing a molding die according to the present embodiment and a state in which a molded skin is formed from a skin via the molding die.

In FIG. 1, 1 is a sheet-like skin, 22
Is a molding die, 2a is a convex molding portion of the molding die 22, 2b is a corner where the side surface of the molding portion 2a intersects, 2c is a corner top of the corner 2b, and 2d is a product end of the molding portion 2a. Showing trim lines,
2e is a base plate of the mold 22; 2f is a small hole for suction;
Reference numeral 3 denotes a substantially trapezoidal guide plate having an area equivalent to the remaining skin provided along the corners 2b where the side surfaces intersect.

FIG. 2 is an explanatory view showing a state in which the molded skin according to the embodiment is inserted into a foaming mold and foamed.

In FIG. 2, reference numeral 12A denotes a foaming mold comprising a core mold 8 and a cavity mold 27.
A molded skin 24 is inserted into 7. And 27
“a” is a recessed portion, into which the bridge 26 is inserted.

In the bridge 26, there is a gap between the guide plate 23 and the guide plate 24.
In the portion lacking, the inner surface of the molded skin 24 heated and softened at the time of molding is fused to form one skin, and the skin fusion portion 26 is formed.
a is formed and the gap disappears.

Therefore, as shown in the perspective view of FIG. 2, the bridge 26 inserted into the recess 27a has the same seal as the conventional one because the notch 23a of the guide plate 23 is fused. There is no need to attach the tape 5. When the core die 8 is clamped to the bridge portion 26 that has not been fused, the sealing material 10 is in contact with the bridge portion 26 to close the gap between the molded skins 24, preventing the foam material 13 from entering and preventing the foam material 13 from leaking. The structure is such that it can be prevented.

A description will now be given of the skin molding using the molding die 22 configured as described above and the foam molding using the molded skin.

First, the formation of the molded skin 24 will be described with reference to FIG. 1. The molding die 22 presses the heated and softened skin 1 against the molding portion 2a, and simultaneously sucks the molded skin 2 from the small hole 2f to form the molded skin. Adsorb to the mold 22. Subsequently, when the shape is cooled and the shape is maintained, the mold is removed to obtain a molded skin 24. At this time, the surplus skin is always formed in the same shape at the same position in a bridge shape via the guide plate 23.

The guide plate 23 is provided in a substantially trapezoidal thin plate having a portion from the corner top 2c to the vicinity of the trim line 2d of the product cut off from the corner top 2c to the base plate 2e along the corner 2b where the side surfaces intersect. Therefore, when the excess skin is guided and attracted by pulling it, a small bridge-like shape is generated in the notch 23a, and the heated and softened skin 1 overlaps and fuses together. Therefore, the missing portion 23a of the guide plate 23
Can obtain a skin fused portion 26a fused without a gap.

Next, foam molding using the molded skin 24 will be described.

FIG. 2 shows a state in which the molded skin 24 is inserted and the foam material 13 is inserted.
Is shown. In inserting the molded skin 24, the bridge 26 is inserted into a recess 27a provided in a groove shape in the cavity mold 26, and the entire molded skin 24 is inserted into the foam molding mold 12 while being spread.

From the mixing head 11, two liquids of the foaming material 13, the A liquid and the B liquid, are applied onto the molded skin 24 mounted in the cavity mold 27.
Inject a suitable amount while stirring inside.

Immediately, the core material 9 is detachably mounted, and the core die 6 provided with the sealing material 10 joined to the periphery of the mounted core material 9 is lowered in the arrow Y direction to clamp the die. Perform

The foam material 13 injected into the foam mold 12A reacts rapidly and expands to fill the foam mold 12A. At this time, the foaming pressure of the foam material 13 is applied to the inside of the foaming mold 12A, but the gap is closed by the seal material 10 in the bridge 26 where it is fused or not fused, and the seal tape 5 is used. It is foamed without any problems. Then, when the reaction of the foam material 13 is completed, the foam material 13 is released from the foam mold 11A to form a resin molded product in which the core material 9 and the molded skin 24 are integrated with the foam material 13.

Here, the skin 1 is a resin material obtained by blending an ABS resin and vinyl chloride into a sheet shape by using an extruder or a calender roll device. Many of them are used. Those having a skin thickness of 0.7 mm or 0.8 mm are common as vehicle interior materials.

Here, the foaming material 13 refers to a urethane foaming material, in which a polyol as a liquid A and an isocyanate as a liquid B are mixed and stirred by a mixing head 11 and foamed along the inner shape of the mold. A layer is formed. These two liquids have the property of reacting violently in a very short time, flowing at high speed and expanding, and penetrating into narrow gaps.

Here, the sealing material 10 generally refers to a material obtained by slicing a urethane foam molding material into a string shape having a cross section such as a round or a square. This sealing material 10
Is soft in a foamed state and can be easily joined along the uneven surface of the molded product. In addition, when the foam 13 receives the pressure, the foam 13 deforms in the pressed direction and fills the gap, thereby preventing the foam 13 from leaking.

[0031]

As described above, according to the first aspect of the present invention, a guide plate is provided near the corner of the formed portion for guiding and shaping a part of the remaining skin. The extra skin is provided to be guided from a position slightly lower than the top of the corner of the molded part.

Therefore, the outer skin is formed along the guide plate so as to be pulled, and becomes a bridge having a certain stable shape. In addition, the use of this skin enables accurate insertion into the foaming mold, thereby reducing molding defects.

Further, the surplus skin between the corners of the molded portion and the guide plate is fused to form a single sheet without any gap, and there is no need to apply a sealing tape to prevent leakage of the foam material.

Accordingly, the sealing tape is not required, and the sticking operation is not required, so that the manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing skin formation according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing foam molding using the molded skin according to the embodiment.

FIG. 3 is an explanatory view showing a conventional skin molding.

FIG. 4 is a cross-sectional view showing foam molding using the molded skin according to the conventional technique.

FIG. 5 is a perspective view of a Q section according to FIG. 4;

[Explanation of symbols]

 22: Mold 23: Guide plate 1: Skin 2a: Molded part 2b: Corner 2c: Corner top

Claims (1)

[Claims] 1. A molding die for forming a skin along a molding portion by pressing a sheet-like skin made of a thermoplastic plastic toward a convex molding portion while heating and softening the same. A guide plate for guiding and shaping a part of the surplus skin is provided in the vicinity of the corner, and the guide plate is provided so as to guide the surplus skin from a position slightly lower than the top of the corner of the molded portion. A molding die characterized by the following.