JP3090252B2 - Forming method of foamable base material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for molding a foamable base material such as a foamed PPO base material, and more particularly to a method for easily terminating a peripheral edge and preventing deformation of the peripheral edge. The present invention relates to a method for forming a foamable base material, which can improve the external appearance.

[0002]

2. Description of the Related Art In recent years, foamed PPO (polyphenylene oxide) has been required for a roof trim for an automobile to be mounted on a roof panel of a passenger car, since it is desired to be lightweight and have excellent rigidity and heat resistance. (Abbreviation) There is a tendency that a substrate is frequently used.

FIGS. 10 and 11 are a front view and a sectional view showing a roof trim using a foamed PPO base material. A roof trim 1 has a skin material 3 such as a cloth adhered to the surface of a foamed PPO core material 2. On the front surface of the roof trim 1, recesses 1a for storing and installing a sun visor (not shown) are provided on the occupant side and the passenger seat side, respectively, and the passenger seat side and the rear seat are provided. Recess 1 for storing and installing assist grips installed on both sides of the occupant
b are provided at three places.

The roof trim 1 is set along the edge as shown in FIG. 11 to enhance the rigidity of the front edge or the front and rear edge. The rigidity is enhanced by bending and fixing the folded portion 4 to the rear surface side.

[0005] However, even if the thickness of the foamable core material 2 in the folded portion 4 is set to be thin in consideration of the folding operation of the folded portion 4, the 3
mm or less, the reaction force of the folded portion 4 acts strongly. Conventionally, as shown in FIG. 12, a heat-welded portion 5 is set and pressure-bonded by heat-welding. That is the fact.

[0006]

As described above, conventionally, the folded portion 4 is folded back to the back side along the front edge or the front and rear edges of the roof trim 1, and folded by heat welding. Since the part 4 was securely bonded and fixed, for example, as a result of a heat cycle test, FIG.
As shown in FIG. 13, meandering deformation occurs along the edge, and FIG.
It has been pointed out that the deformation amount is 1 to 7 mm indicated by the middle symbol d, which significantly reduces the appearance of the peripheral edge, and also causes poor alignment with a mating part such as a roof garnish.

[0007] The present invention has been made in view of such circumstances, and the edge of a foamable base material such as a foamed PPO core material is not deformed after a heat cycle test, and the appearance is excellent. It is another object of the present invention to provide a method for forming a foamable base material, which can accurately perform positioning with a counterpart component.

[0008]

Means for Solving the Problems To achieve the above object, the present invention relates to a method of cold-pressing a sheet-like foamable base material into a desired shape by a cold press forming upper and lower mold after heating and expanding the sheet-like foamable base material by a heater device. It is characterized in that the edge is solidified into a thin-walled shape by performing hot press molding and then cold press molding along the edge of the foamable base material.

Here, the foamable base material is a material which can be drawn and formed by a cold press forming die having a required shape after a sheet-shaped raw material is heated and expanded in a preheating softening step. However, for example, a foamed PPO resin base material is suitable.

Next, as a mold device used for molding the foamable base material, there are an upper and lower mold for cold press molding for molding a general portion except for an edge into a required shape, and a hot press mold for molding an edge. And a cold press mold,
The hot press mold and the cold press mold are alternately arranged on the outer periphery of the upper and lower molds for cold press molding, and hot press molding and cold press molding are performed in this order along the edge of the foamable base material.

In the step of preheating the expandable base material, when the expandable base material is, for example, a foamed PPO base material, the PPO resin is heated to a melting point of 160 to 180 ° C. to be in an expanded state.

In cold press molding, the temperature of each mold is 60 ° C. for 20 seconds, 1.6 kg / cm ^2.
To form a general portion of the foamable base material.

Also, along the edge of the foamable base material, 2
A hot press mold having a mold temperature of 00 ° C. is arranged, hot press molding is performed by applying a press pressure of 4.1 kg / cm ² for 5 seconds, and then a cold press mold having a mold temperature of 60 ° C. is used. Cold press molding is performed by applying a pressure of 4.1 kg / cm ² for １５15 seconds.

During hot press molding using a hot press mold, a non-woven fabric (for example, having a melting point of 260.degree. Polyester fiber non-woven fabric).

Further, hot press molding and cold press molding are alternately performed along the edge of the foamable base material, and the edge is solidified. And terminal processing is performed.

As is apparent from the above-described structure, according to the method of the present invention, when the foamable base material is formed, the edge portion thereof can be solidified into a thin wall, and the reaction force due to the restoration as in the prior art can be improved. Does not act, and the edge can be easily adhered and fixed to the back surface of the base material by hand.

Therefore, since irregularities due to thermal welding are not formed unlike the conventional case, the deformation after the thermal cycle test can be controlled to be extremely small.

Further, since the amount of deformation after the heat cycle test is small, it is possible to eliminate the work of folding the edge.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of a method for molding a foamable substrate according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a front view showing a roof trim for an automobile manufactured by applying the method of the present invention, FIG. 2 is a sectional view of an essential part showing the structure of the roof trim for the automobile, and FIGS. FIG. 9 is a sectional view showing a main part of another embodiment of a roof trim for an automobile manufactured by applying the method of the present invention.

1 and 2, a roof trim 10 for an automobile has a recess 10a for accommodating a sun visor on the occupant side and a sun visor on the passenger seat side at the front side.
Are formed, and concave portions 10b for accommodating the assist grip are formed at three places on both sides of the passenger seat and the rear seat occupant.

As shown in FIG. 2, the roof trim 10 for automobiles has a foamed PPO core material 20 formed into a required shape, and is integrally adhered to the surface of the foamed PPO core material 20 to obtain a good surface feel. And a skin material 30 having a surface appearance.

More specifically, the foamed PPO core material 20
Has a structure in which a PPO resin skin layer 22 is integrally formed on the front and back surfaces of a PPO resin foam layer 21, respectively. The PPO resin in the present embodiment is not pure PPO, but polystyrene is added in consideration of cost and the like. , Using a deformed one.

As specific numerical values, a PPO resin foam layer 21 having a basis weight of 500 to 600 g / m ² and a PPO resin skin layer 22 having a thickness of 0.18 mm is used.
The material having a total thickness of 3.5 mm at the time of the raw material of the PO resin base material is softened by heating to 130 to 140 ° C. in a heating step described below, and the total thickness of the PPO resin base material is expanded to 6 to 8 mm. Foamed PPO core material 2 by molding
The thickness is 0, the edge is 2-3 mm, and the general part is 6 m
m is used.

On the other hand, as the skin material 30, a material obtained by laminating a hot melt film 32 on the back surface of the cloth 31 is used. The foamed PPO core material 20 and the skin material 30 are overlapped and preheated, and both are cold-pressed. By doing so, the foamed PPO core material 20 and the skin material 30 are integrated via the hot melt film 32.

The cloth 31 and the hot melt film 3
A pad material such as a polyurethane foam may be interposed between the second member and the second member in order to enhance cushioning.

The feature of the present invention is that the rigidity of the front side edge 12 and the rear side edge 13 of the roof trim 10 can be enhanced, and the edges 12 and 13 can be deformed after the heat cycle test. An object of the present invention is to provide a molding method capable of easily providing a roof trim 10 having good appearance and excellent positioning accuracy with respect to a counterpart part by suppressing as much as possible.

That is, as shown in FIG. 2, the folded portion 1 extends along the front edge 12 of the roof trim 10.
1 is folded back on the back side of the product, and is firmly adhered and fixed with a general-purpose adhesive such as a urethane adhesive or an acrylic adhesive (not shown).

Since the folded portion 11 is solidified and does not exert a restoring force unlike the general portion of the foamed PPO core material 20, the folding operation of the folded portion 11 can be performed smoothly, and the folding workability is improved. In addition to the conventional method, unevenness due to thermal welding does not occur unlike the prior art, so that deformation such as meandering that occurs after a thermal cycle test does not occur, a sharp edge shape is secured, and the design is extremely excellent.

Next, a method of solidifying the folded portion 11 along the edges 12 and 13 of the roof trim 10 will be described in detail with reference to FIGS.

First, in the preheating step shown in FIG. 3, the foamed PPO core material 20 and the skin material 30 are put in a superposed manner between the upper and lower heater devices 40, and the foamed PPO core material 20 and the skin material are interposed between the heater devices 40. Heat soften 30 to 130-140 ° C.

Next, the expanded P foamed into the press mold.
The PO core material 20 and the skin material 30 are set. First, a schematic configuration of a press die will be described. This press die includes a lower die 50 for cold press molding, each having a curved die surface, and a cold press. The upper mold 60 for forming, and the hot press mold 70 and the cold press mold 80 alternately arranged on a part of the outer periphery (front side edge and rear side edge) of the upper and lower molds 50, 60 for cold press molding. It is roughly composed of

More specifically, the upper mold 60 for cold press molding is configured to be able to move up and down by a predetermined stroke by an elevating cylinder 61, and the hot press mold 70 is mounted on the upper plate 62 of the upper mold 60 for cold press molding. It is supported by the attached cylinder 71 so as to be able to move up and down by a predetermined stroke, and is also supported by the cylinder 71 attached to the lower plate 51 so as to be able to move up and down by a predetermined stroke in the hot press mold 70 installed in the lower mold 50. I have.

The cold press molds 80 are located outside the hot press molds 70, respectively.
2, the upper die 60 is provided so as to be able to advance and retreat by a cylinder 81 attached to the lower plate 51, respectively.
To the position where it contacts the side wall surface of the lower mold 5
After the 0 hot press mold 70 descends, it enters by the operation of the cylinder 81 to a position where it contacts the side wall surface of the lower mold 50.

As shown in FIG. 4, when the upper and lower molds 50 and 60 for cold press molding are in the mold open state, the expanded PPO core material 20 and the skin material 30 which have been expanded through the preheating step are connected to the upper and lower molds. Set in 50 and 60.

At this time, each of the hot press dies 70 is extended by the extension operation of the cylinder 71.
Is located on substantially the same plane as the upper and lower molds 50 and 60 for cold press molding.

Incidentally, a polyester fiber nonwoven fabric 72 is adhered to the mold surface of the hot press mold 70, so that the material is effectively prevented from adhering to the mold surface of the hot press mold 70.

Next, as shown in FIG. 5, the upper die 60 for cold press molding performs a predetermined stroke lowering operation by the operation of the cylinder 61 for raising and lowering, and the upper and lower dies 50 and 60 for cold press molding form the foamed PPO core material 20 and The skin material 30 is integrally formed in a required shape.

The upper and lower dies 50, 6 for cold press molding are used.
The mold temperature of 0 is 60 ° C. and 1.6 kg / c for about 20 seconds.
Cold press molding is performed at a press pressure of m ² .

At this time, the folded portion 11 is formed along the front edge 12 and the rear edge 13 of the roof trim 10.
Is hot-pressed with a press pressure of about 4.1 kg / cm ² for about 5 seconds from above and below by a hot press mold 70 and the hot press mold 70 is maintained at 200 ° C. It is hot-pressed to a thickness of about 3 mm.

Then, as shown in FIG. 6, the upper die 60 is raised, and the hot press die 70 located on the outer periphery of the upper and lower dies 50, 60 is provided with spaces S at the upper and lower portions of the folded portion 11 by the operation of reducing the cylinder 71. Is set.

Next, as shown in FIG.
Is operated, the cold press die 80 enters the space S, and the cold press die 80 is located on the outer periphery of the upper and lower dies 50 and 60 for cold press molding.

Thereafter, the upper and lower dies 5 for cold press molding
The mold is clamped at 0 and 60 to cool it down from the upper and lower surfaces of the folded portion 11 by a cold press mold 80 under predetermined press conditions (press time of about 12 to 15 seconds, press pressure of about 4.1 kg / cm ² ). It is solidified into a thin shape.

As described above, according to the method of the present invention, the hot press mold 70 and the cold press mold 80 are alternately arranged on the outer periphery of the upper and lower molds 50, 60 for cold press molding, and the general part of the roof trim 10 is The upper and lower dies 50 and 60 for cold press forming are used to draw and form a desired shape, and the folded portion 11 along the front side edge 12 and the rear side edge 13 of the roof trim 10 is first formed by a hot press mold 70. Hot-press molding is performed, followed by cold-press molding with a cold-press mold 80, so that a thin-walled solid can be obtained by a two-stage pressing process. This enables reliable bonding and fixing.

Since unevenness due to heat welding is not formed as in the prior art, the deformation after the heat cycle test is 0.5 to 100%.
It can be suppressed to about 1.0 mm, a sharp edge line can be formed, the appearance of the edge can be maintained beautifully, and the alignment accuracy with a mating part such as garnish can be improved.

Further, since the amount of deformation after the heat cycle can be suppressed to a small value, as shown in FIG.
May be abolished and the configuration may be such that only trim cut processing is performed.

In such a case, there is an advantage that the turning operation of the turning section 11 can be abolished and the cost can be reduced due to the reduction of the man-hour.

[0048]

As described above, the present invention has the following special functions and effects.

(1) In the method for molding a foamable base material according to the present invention, hot press molding and cold press molding are alternately performed along the edges of the base material during cold press molding of the foamable base material. Since the edge of the base material can be solidified into a thin wall, for example, when the edge is folded back to the back side, the reaction force from the folded portion is extremely small, so smooth folding work can be expected In addition, since good adhesion can be performed with a general-purpose adhesive, the work of folding the edge can be performed smoothly, and the workability can be significantly improved.

(2) The method for molding a foamable base material according to the present invention comprises the steps of hot press molding,
Since cold press molding is performed alternately and solidified in a thin shape along the edges of the foamable base material, there is no need to heat weld the edges as in the past,
Since the unevenness caused by this is not formed, the deformation after the heat cycle test was conventionally 1 to 7 mm to 0.5 to
Since the thickness can be suppressed to 1.0 mm, the appearance of the peripheral edge along the edge can be significantly improved, and the accuracy of alignment with the mating component can be improved.

(3) Since the method for molding a foamable substrate according to the present invention involves performing hot press molding and then cold press molding along the edge of the substrate, the edge of the foamable substrate is Can be solidified into a thin-walled shape, suppressing deformation and providing sufficient rigidity. Have.

[Brief description of the drawings]

FIG. 1 is a front view showing an automobile roof trim formed by the method of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a sectional view showing a step of preheating a foamable substrate according to the method of the present invention.

FIG. 4 is a cross-sectional view showing a setting step of setting a foamable substrate in a mold in the method of the present invention.

FIG. 5 is a cross-sectional view showing a hot press molding step of a substrate edge portion in the method of the present invention.

FIG. 6 is a cross-sectional view showing a mold opening state after hot press molding in the method of the present invention.

FIG. 7 is a sectional view showing an arrangement of a cold press die in the method of the present invention.

FIG. 8 is a cross-sectional view showing a cold press forming step of a substrate edge portion in the method of the present invention.

FIG. 9 is a cross-sectional view of a principal part showing another embodiment of an automobile roof trim manufactured by applying the method of the present invention.

FIG. 10 is a front view showing a conventional automobile roof trim.

11 is a sectional view taken along line XI-XI in FIG.

FIG. 12 is an explanatory diagram showing a terminal processing configuration in a conventional roof trim.

FIG. 13 is a view taken in the direction of arrow A in FIG. 12;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Roof trim for automobiles 11 Folding part 12 Front edge 13 Rear edge 20 Foamed PPO core material 30 Skin material 40 Heater device 50 Lower mold for cold press molding 60 Upper mold for cold press molding 70 Hot press mold 72 High melting point fiber non-woven fabric 80 Cold press type

Claims (4)

(57) [Claims] 1. A sheet-like foamable base material (20) is heated and expanded by a heater device (40), and then cold-pressed into a required shape by upper and lower dies (50, 60) for cold press molding. Along with the edge portions (12, 13) of the conductive base material (20), hot press molding and then cold press molding are performed, whereby the edge portions (12, 1) are formed.
A method for molding a foamable base material, wherein 3) is solidified into a thin wall. 2. An upper and lower mold (50, 6) for cold press molding.
A hot press mold (7)
0), the cold press molds (80) are alternately arranged to form the edges (12, 13) of the foamable base material (20).
2. The method according to claim 1, wherein the hot press molding and the cold press molding are alternately performed in accordance with the conditions. 3. The hot press mold (70) has a mold surface,
The method according to claim 1, wherein a high melting point nonwoven fabric (72) is attached. 4. The solidified edge portion (12, 1)
4. The method for molding a foamable base material according to claim 1, wherein 3) is a folded portion (11) that is folded back and fixed to the back surface side.