JPH0939005A - Powder slush mold - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To directly heat the molding surface 3 of the surface and maintain it at the resin welding temperature, and drop the powder resin 31 on the heating molding surface 3 to cause the welding, and to powder the skin material W. The opening W1 can be formed in the skin material W at the same time as the molding for the slush molding type mold, and the amount of the powder resin 31 used is reduced. An opening W1 of a skin material W on a molding surface 3
The cooling mechanism 8 containing the water absorbing material 11 is attached to the back surface of the molding die body 1 corresponding to the opening forming portion 5 that forms the cooling water 2 that is sprayed toward the back surface of the molding die body 1 in the cooling process.
3 is stored in the water absorbing material 11 of the cooling mechanism 8, and in the subsequent heating step, the stored water 23 is evaporated and released from the water absorbing material 11, and the opening forming portion 5 of the molding surface 3 is cooled by the heat of evaporation of this water. Then, the temperature is kept low to prevent welding of the powder resin 31 to the opening forming portion 5 to form the opening W1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a powder slush molding die for forming openings in a skin material at the same time as molding the same.

[0002]

2. Description of the Related Art Generally, when molding a skin material of this type by powder slush molding, a molding is made up of a box-shaped molding die having a molding surface on the inner surface and a storage box for storing powder resin as the skin material. A device is provided, and the mold is placed on the storage box with the opening facing downward, and the mold opening is sealed to match the opening that opens above the storage box. After heating and holding at the specified mold temperature, reverse the molding device so that the storage box is located on the upper side and the molding die is located on the lower side, and the powder resin in the storage box is dropped onto the molding surface of the molding die. Then, it is heated and melted into a shape along the molding surface. Then, after the molding, the molding device is inverted to the original posture to collect the excess powder resin in the molding die in the storage box, and the skin material having a predetermined thickness can be molded by repeating the above operation several times. Has been done.

When forming an opening in such a skin material, if the opening can be formed at the same time as molding, the amount of powder resin raw material required for molding is smaller than in the case where the opening is punched after molding. It is possible to manufacture the epidermis at a low cost and at a low cost.

As a powder slush molding die capable of satisfying such requirements, the one disclosed in Japanese Patent Application Laid-Open No. 2-26714 discloses that the molding die is heated from the back side with a heating medium sand heating means to form a molding surface. When heating above the welding temperature of the powder resin, by placing the heat insulating plate on the part of the molding surface that does not weld the powder resin, keep the molding surface of the heat insulating plate part at a temperature lower than the welding temperature of the powder resin. The powder resin is prevented from welding, and the non-welded portion forms an opening.

[0005]

However, in the above-mentioned proposal, when the molding surface of the molding die is heated from the back surface side of the die, a predetermined portion of the molding surface is insulated by a heat insulating plate on the molding surface. Therefore, when applying this proposal to a mold that directly heats the molding surface from the surface side, the heat insulating plate on the molding surface is heated together with the molding surface to raise the temperature. As a result, it becomes difficult to keep the temperature of the molding surface of the portion forming the opening of the skin material at a low temperature due to the heat insulating effect of the heat insulating plate, which is practically not applicable.

The present invention has been made in view of the above points, and an object thereof is to directly heat the molding surface from the surface side by improving the cooling structure at the time of molding for the molding surface of the powder slush molding die. Even with the mold of
An object of the present invention is to lower the molding surface temperature of the portion of the skin material where the opening is formed so that the opening can be formed at the same time as molding, and the required amount of the powder resin can be reduced so that the skin can be manufactured at low cost.

[0007]

In order to achieve the above object, in the present invention, a cooling means having a water absorbing material is arranged on the back surface side of the molding die opposite to the molding surface. The water-absorbent material was made to absorb the water sprayed on the back surface of the molding die and evaporate the water when the molding surface was heated, thereby lowering the temperature of a predetermined portion of the molding surface on the die surface.

That is, according to the first aspect of the present invention, the surface of the molding die body has a molding surface heated from the surface side, and powder resin is welded to the heated molding surface to mold the skin material. The premise is a powder slush molding die in which an opening is formed at the same time as molding.

On the back surface of the molding die body, there is provided cooling means for preventing the molding surface of the portion forming the opening of the skin material from rising to the welding temperature of the powder resin. It is assumed that a water-absorbing material that stores the cooling water jetted toward the rear surface of the mold body and that can release the stored water when the molding surface is heated is built in.

In the invention of claim 2, the above-mentioned claim 1 is adopted.
In the same powder slush mold as the premise of the invention, a mold opening penetrating up to the back surface of the mold body is formed on the molding surface of the portion forming the opening of the skin material. Then, a cooling means for closing the mold opening is provided on the back surface of the mold body,
This cooling means contains a water-absorbing material that absorbs the cooling water sprayed toward the rear surface of the molding die body and can release the absorbed water when the molding surface is heated.

With these constructions, when cooling water is jetted toward the back surface of the molding die before molding, this cooling water is absorbed by the water absorbing material of the cooling means on the back surface of the molding die. After that, the molding surface on the surface of the molding die is heated from the surface side and the temperature rises to the welding temperature of the powder resin, but with this heating, the water stored in the water absorbing material is evaporated and released from the water absorbing material. The heat of evaporation cools only the portion where the cooling means is arranged, and the portion is kept at a temperature lower than the welding temperature of the powder resin. When the mold is inverted and the powder resin is dropped on the molding surface in this temperature distribution different state,
Powder resin is welded to the molding surface heated to the resin welding temperature to form the skin material, but the portion not heated to the resin welding temperature, that is, the cooling means in the invention of claim 1. The powder resin is not welded to the molding surface, that is, the cooling means closing the mold opening in the invention of claim 2, and this portion becomes the opening of the skin material.

Therefore, even if the molding die is a type in which the molding die is heated from the molding surface side, the opening is formed at the same time as the molding of the skin material, and the amount of the powder resin is reduced only in this opening. Therefore, the skin material having the opening can be formed at low cost.

According to the third aspect of the present invention, the water absorbing material is made of activated carbon, ceramic or open-cell urethane foam resin, or a mixture of at least two kinds of these materials. In this case, a water absorbing material having a desirable structure for exerting the above effects can be specifically and easily obtained.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) FIG. 1 shows a powder slush molding die A according to Embodiment 1 of the present invention. In FIG. 1, 1
Is a box-shaped molding die body, a joint flange 2 is formed on the peripheral edge of the opening end, and a molding surface 3 having a predetermined shape for molding the skin material W is provided on the inner surface which is the surface of the molding die body 1. ing. The molding surface 3 is basically exposed to the heating air in the heating chamber 27 in the heating step described later, and is directly heated by the air from the molding surface 3 side to the welding temperature of the powder resin 31 or higher. Powder resin 31 is applied to the molding surface 3.
Are welded to form the skin material W.

An opening forming portion 5 for forming an opening W1 at the same time as forming the skin material W at a predetermined position on the molding surface 3.
Is provided. A continuous protrusion 3a is formed on the molding surface 3 around the opening forming portion 5, and at the time of molding, the temperature of the opening forming portion 5 surrounded by the protrusion 3a is lower than that of other portions of the powder resin 31. By maintaining the temperature below the welding temperature, the opening W1 is formed simultaneously with the molding of the skin material W by the opening forming portion 5.

That is, on the back surface of the molding die body 1,
A cooling mechanism 8 for cooling the opening forming portion 5 at a position corresponding to the opening forming portion 5 of the molding surface 3 during molding to prevent the opening forming portion 5 from rising to the welding temperature of the powder resin 31 ( Cooling means) is attached. The cooling mechanism 8 has a bottomed box-shaped frame body 9 having an open end closely attached to the back surface of the mold body 1 on the back surface of the molding die body 1. (Close to 1 and the wall on the opposite side)
Is made of expanded metal, for example, and has a large number of holes 10, 10 ,.
The inside and outside of the frame 9 are communicated by 0, ....

A water absorbing material 11 is provided inside the frame body 9 to form the mold body 1.
Is arranged in contact with the back surface of the water absorbent material 11 and the frame 9
A heat insulating fiber layer 12 is formed by filling a heat insulating fiber such as glass wool between the inner wall surface and the inner wall surface. Water absorbing material 11
Is occludes the cooling water 23 that enters the frame body 9 from the holes 10, 10, ... When the cooling water 23 is jetted toward the back surface of the mold body 1 in the cooling step described later, and heats it thereafter. In the step or molding step, the absorbed water 23 can be evaporated and released from the holes 10, 10, ..., Specifically, activated carbon, ceramic or open-cell urethane foam resin, or a material thereof. It consists of a mixture of at least two of them.

Next, the operation of the slush mold A will be described. (Cooling Step) First, as shown in FIG. 2, the molding die A is set on the cooling tank 21 with the molding surface 3 thereof facing upward. At this time, the cooling mechanism 8 on the back surface of the molding die body 1 enters the cooling tank 21, and the joint flange 2 on the peripheral edge of the die body 1 is set so as to close the opening of the cooling tank 21. The cooling tank 21
Is a V-shaped cross section corresponding to the shape of the back surface of the molding die A, and a water spray pipe 22 is stretched around the inner bottom surface thereof, and a large number of cooling water injection holes (not shown) are provided in the water spray pipe 22.
Is opened, and the opening of the cooling tank 21 is opened from this injection hole,
That is, the cooling water 23 is evenly jetted toward the back surface of the mold A that closes the opening.

When the cooling water 23 is sprayed from the spray holes toward the back surface of the molding die A, the entire molding surface 3 on the surface of the molding die A is cooled and a part of the cooling water 2
3 is the holes 10, 10, in the bottom wall of the frame 9 of the cooling mechanism 8.
From the inside of the frame body 9, the cooling water 23 advances through the heat insulating fiber layer 12 in the frame body 9 and is stored in the water absorbing material 11.

Although FIG. 2 shows a state in which the skin material W is present on the molding surface 3 of the molding die A, FIG. 2 basically shows a state in which the skin material W after cooling is cooled, The skin material W is not welded in the cooling step before molding.

(Heating Step) After this cooling step, the mold A is
Is taken out of the cooling tank 21 and is then transferred into the heating tank 25 as shown in FIG. The heating tank 25 has a closed space capable of accommodating the molding die A therein, and a supporting portion 26 is projectingly provided on a side wall portion of the heating tank 25. The supporting flange 26 of the molding die body 1 is attached to the supporting portion 26. And the molding die A is set with the molding surface 3 facing upward. In this state, the space inside the heating tank 25 is partitioned into upper and lower spaces by the mold A, and the upper space serves as the heating chamber 27. By supplying heated air of 220 to 240 ° C. to the heating chamber 27,
The molding surface 3 of the molding die A is directly heated by heated air,
The temperature rises above the welding temperature of the powder resin 31.

At this time, the cooling mechanism 8 on the back surface of the mold main body 1
Is in the lower space of the heating tank 25, but since the water absorbing material 11 is in contact with the back surface of the mold body 1, the heating chamber 27
The molding surface 3 is gradually heated by the heating air. As a result, the cooling water 2 stored in the water absorbing material 11
3 is evaporated, and the opening forming portion 5 on the molding surface 3 is cooled by the heat of evaporation, and the temperature is lower than other portions and lower than the welding temperature of the powder resin 31 (for example, 110).
~ 130 ° C).

(Molding Step) When the molding surface 3 of the molding die A is heated in this manner, the molding die A is maintained while maintaining the heated state.
Is taken out of the heating tank 25, and the process proceeds to the next molding step. In this step, as shown in FIG.
The heating tank 2 is placed on a storage box 29 in which 1 is stored.
The mold A taken out from step 5 is placed so that the open end faces downward, the open end of the mold A is aligned with the open end that opens to the upper side of the storage box 29, and the joining flange 2 of the mold A is stored around the storage box 29. It is tightly attached to the joining flange 30 of No. 3 and sealed.

Next, the top and bottom of the forming die A and the storage box 29 are turned upside down to arrange the storage box 29 on the upper side and the forming die A on the lower side. Along with this reversal, the powder resin 31 in the storage box 29 drops onto the heated molding surface 3 of the molding die A, is welded to the molding surface 3 and is molded into a shape along the molding surface 3. After this molding, the molding die A and the storage box 29 are inverted to the original postures shown in FIG. 4, and the excess powder resin 31 in the molding die A is collected in the storage box 29. By repeating the above operation several times, the skin material W having a predetermined thickness is formed.

During the molding of the skin material W, the temperature of the opening forming portion 5 of the molding surface 3 is lower than that of the other portions and is lower than the welding temperature of the powder resin 31. Of the molding surface 3 of which the temperature is raised to the resin welding temperature.
The powder resin 31 is welded to the outer surface W to form the skin material W, but the powder resin 31 is not welded to the opening forming portion 5, and this portion becomes the opening W1 of the skin material W.

After this molding, the mold A is stored in the storage box 29.
And set in the cooling tank 21 (see FIG. 2),
The molding surface 3 and the skin material W on the molding surface 3 are cooled from the back surface side of the molding die body 1 by jetting the cooling water 23 from the water spray pipe 22 (cooling step). After this cooling, the skin material W on the molding surface 3 may be taken out.

Further, even after taking out the skin material W, the cooling water 23 is continuously jetted, and the cooling water 23 is stored in the water absorbing material 11 of the cooling mechanism 8 on the rear surface side of the molding die A as described above.
After that, the same process is repeated and a large number of skin materials W, W,
... are formed in order.

Therefore, in this embodiment, even if the molding die A is a type in which the molding die A is heated from the molding surface 3 side of the surface to the resin welding temperature in the heating step, the temperature of the opening forming portion 5 of the molding surface 3 is increased. It is possible to form the opening W1 simultaneously with the molding of the skin material W by lowering only one portion of the skin material W, and the amount of the powder resin 31 can be reduced by the amount corresponding to the opening W1. The material W can be formed at low cost.

When the existing mold A is modified so that the opening W1 can be formed when the skin material W is molded,
The above effect can be obtained only by attaching the cooling mechanism 8 to the back surface of the predetermined portion (opening forming portion 5) on the molding surface 3 of the mold body 1. Therefore, the cost of modifying the molding die A can be reduced.

(Second Embodiment) FIG. 5 shows a second embodiment (note that the same portions as those in FIG. 1 are designated by the same reference numerals and detailed description thereof will be omitted). In this embodiment, the mold A
Of the surface W of the skin material W, a mold opening 4 is formed so as to penetrate to the back surface of the mold main body 1, and the cooling mechanism 8 is provided on the back surface of the mold main body 1. It is attached so as to close 4. This cooling mechanism 8
Has a support plate 13 that closes the mold opening 4.
3 is a peripheral portion of the heat insulating material 1 to the back surface of the mold main body 1.
5 are joined. That is, the mold opening 4
The opening forming portion 5 is formed by the surface of the support plate 13 that closes the opening. The frame 9, the water absorbing material 11, and the heat insulating fiber layer 12 are arranged in close contact with each other on the back surface of the support plate 13. Further, the protrusion 3a is not formed on the molding surface 3 around the periphery of the mold opening 4. The other configurations are the same as those in the first embodiment.

In the case of this embodiment, in the heating step,
When the cooling water 23 stored in the water absorbing material 11 of the cooling mechanism 8 evaporates, the support plate 13 is cooled by the evaporation heat. This support plate 13 is provided on the rear surface of the mold main body 1 with a heat insulating material 15.
The mold opening 4 is closed in a state of being attached through the surface of the mold, and the surface is exposed to the molding surface 3 side, and the opening forming portion 5 is formed by the exposed surface. This is much lower than the molding surface 3 of. For this reason, when the skin material W is welded on the molding surface 3 in the subsequent molding step, the powder resin 31 is hardly welded to the opening forming portion 5 on the surface of the support plate 13. As a result, although it is necessary to modify the mold A to open the mold opening 4, the required amount of the powder resin 31 can be further reduced as compared with the first embodiment.

[0032]

As described above, according to the first aspect of the invention, in the molding die in which the surface molding surface is directly heated from the surface side and the skin material having the opening is powder slush molded, The cooling means containing the water absorbing material is arranged on the back surface of the molding die corresponding to the molding surface forming the opening of the material, and the water absorbing material is made to absorb the cooling water jetted toward the back surface of the molding die, and the absorbed water Was vaporized when the molding surface was heated to cool a predetermined portion of the molding surface. Also,
In the invention of claim 2, a mold opening reaching the back surface of the molding die is opened in the molding surface forming the opening portion of the skin material, and the mold opening is formed from the back surface of the molding die by the cooling means containing the water absorbing material similar to the above. I tried to close it. Therefore, according to these inventions, even if the powder slush molding die of the type that directly heats the molding surface of the surface from the surface side, it is possible to reduce the amount of powder resin required by forming the openings at the same time when molding the skin material. Therefore, the skin material having the opening can be formed at low cost.

In particular, according to the first aspect of the invention, since it is only necessary to dispose the cooling means on the back surface of the existing mold, the cost for modifying the mold can be reduced.

On the other hand, according to the second aspect of the invention, since the cooling means is exposed to the molding surface side through the mold opening of the molding die, it is possible to eliminate the welding of the powder resin to that portion as much as possible. The required amount of powder resin can be further reduced.

According to the third aspect of the present invention, the water absorbing material is activated carbon, ceramic or open-cell urethane foam resin,
Alternatively, by using a mixture of at least two kinds of these materials, a water absorbing material having a desirable structure for exerting the above effects can be specifically and easily obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a molding die according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a cooling step.

FIG. 3 is a cross-sectional view showing a heating process.

FIG. 4 is a cross-sectional view showing a molding process.

FIG. 5 is a sectional view showing a main part of a molding die according to a second embodiment of the present invention.

[Explanation of symbols]

 A powder slush mold 1 mold main body 3 molding surface 4 mold opening 5 opening forming part 8 cooling mechanism (cooling means) 11 water absorbing material 13 support plate 23 cooling water 27 heating chamber 31 powder resin W skin material W1 opening

Claims (3)

[Claims] 1. A surface of a molding die body has a molding surface heated from the surface side, and a powder resin is welded to the heated molding surface to mold a skin material, and at the same time as molding, an opening is formed. In the powder slush molding die to be formed, on the back surface of the molding die body, a cooling means for suppressing the molding surface of the portion forming the opening of the skin material from rising to the welding temperature of the powder resin, A powder slush molding die characterized in that the cooling means contains a water-absorbing material that occludes cooling water sprayed toward the back surface of the molding die body and can release the occluded water when the molding surface is heated. . 2. The molding die body has a molding surface which is heated from the surface side, the powder resin is welded to the heated molding surface to mold the skin material, and the opening is formed simultaneously with the molding. In the powder slush molding die configured to be formed, a mold opening penetrating to the back surface of the molding die body is formed on the molding surface of the portion forming the opening portion of the skin material, and the die is formed on the back surface of the molding die body. Cooling means for closing the opening is provided, and the cooling means incorporates a water absorbing material capable of absorbing the cooling water jetted toward the rear surface of the mold body and releasing the absorbed water when the molding surface is heated. A powder slush mold that is characterized by that. 3. The powder slush mold according to claim 1 or 2, wherein the water absorbing material is made of activated carbon, ceramic or open-cell urethane resin, or a mixture of at least two kinds of these materials. Characteristic powder slush mold.