JPH09254174A - Molding of foamable base material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply perform terminal treatment along an end edge part and to certainly prevent the meandering deformation of the end edge part after a heat cycle test in a foamable base material molding method performing cold press molding after preheating softening. SOLUTION: A foamable base material 20 is heated and expanded by a heater not only to be subjected to cold press molding by upper and lower molds 50, 60 for cold press molding having a required shape so as to have a desired shape but also to be successively subjected to the hot press molding by a hot press mold 70 and the cold press mold 80 along the folded-back part 11 provided along the end edge part of the foamable base material 20 to solidify the folded- back part provided along the end edge part of the foamable base material 20 in a thin-walled state. By this constitution, terminal treatment is made smooth and deformation after a heat cycle test is prevented to the utmost.

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 in particular, it is possible to easily carry out end treatment of the peripheral edge portion and prevent deformation of the peripheral edge portion. The present invention relates to a method for molding a foamable base material capable of improving the appearance and appearance.

[0002]

2. Description of the Related Art In recent years, foamed PPO (polyphenylene oxide) has been used because it is desirable that it is lightweight and has excellent rigidity and heat resistance as an automobile roof trim installed in a roof panel of a passenger car. The abbreviation) tends to be used frequently.

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

The roof trim 1 is set along the edge portion as shown in FIG. 11 in order to enhance the rigidity of the front edge portion or the front and rear edge portions. Rigidity is strengthened by bending and fixing the folded-back portion 4 on the back surface side.

However, even if the thickness of the expandable core material 2 in the folded-back portion 4 is set to be thin in consideration of the folded-back operation of the folded-back portion 4, the foaming PPO core material 2 is restored by the restoring action.
Since it cannot be adjusted to be less than or equal to mm, the reaction force of the folded-back portion 4 acts strongly, and conventionally, as shown in FIG. 12, the heat-welded portion 5 is set and pressure-bonded by heat-welding. The reality is that

[0006]

As described above, in the related art, the folding portion 4 is folded back to the back side along the front side edge portion or the front and rear side edge portions of the roof trim 1 and is folded by heat welding. Since the part 4 was securely bonded and fixed, for example, as a result of the heat cycle test, as shown in FIG.
As shown in FIG. 13, a meandering deformation occurs along the edge portion,
It has been pointed out that a deformation amount of 1 to 7 mm indicated by a medium symbol d is a factor that significantly deteriorates the appearance of the peripheral edge, and a misalignment with a mating component such as a roof garnish occurs.

The present invention has been made in view of the above circumstances, and does not cause deformation after the heat cycle test at the edge portion of a foamable base material such as a foamed PPO core material, and is excellent in appearance. Moreover, it is an object of the present invention to provide a method for molding a foamable base material that can be accurately aligned with a counterpart component.

[0008]

In order to achieve the above object, the present invention provides a sheet-shaped foamable base material which is heated and expanded by a heater device and then cold-pressed into a desired shape by an upper and lower die for cold press molding. The molding is characterized in that the edge portion is solidified into a thin wall by performing hot press molding and cold press molding along the edge portion of the foamable base material.

Here, the foamable base material is particularly a raw material as long as it can be drawn by a cold press molding die of a required shape after a sheet-shaped material raw material is heated and expanded in a preheating and softening step. However, for example, a foamed PPO resin substrate or the like is suitable.

Next, as a mold device used for molding the foamable base material, a cold press molding upper and lower molds for molding the general portion except the end edge portion into a required shape, and a hot press die for molding the end edge portion. And cold press type,
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 substrate.

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

In cold press molding, each mold temperature is 60 ° C. for 20 seconds and 1.6 kg / cm ²
The foaming base material general part is molded by applying the pressing pressure of.

In addition, 2 along the edge of the foamable substrate.
A hot press die having a die temperature of 00 ° C. was placed, a press pressure of 4.1 kg / cm ² was applied for 5 seconds to perform hot press molding, and then a cold press die having a die temperature of 60 ° C. was used for 12 seconds. Cold press molding is performed by applying a pressing pressure of 4.1 kg / cm ² for about 15 seconds.

During hot press molding with a hot press mold, a non-woven fabric made of high melting point fibers (for example, melting point 260 ° C.) is formed on the mold surface of the hot press mold in order to prevent the foamable substrate from adhering to the hot press mold. Polyester fiber non-woven fabric, etc.) can be attached.

Further, hot press molding and cold press molding are alternately performed along the edge of the foamable substrate to solidify the edge, and then the solidified edge is applied to the back surface of the substrate. It is characterized in that it is folded back and fixed to the end and terminal treatment is performed.

As is apparent from the above-mentioned constitution, according to the method of the present invention, it is possible to solidify the edge portion of the foamable base material into a thin wall at the time of molding, and the reaction force due to the restoration as in the prior art. Does not work, and the edge portion can be easily bonded and fixed to the back surface side of the base material by hand.

Therefore, since the unevenness due to heat welding is not formed unlike the conventional case, the deformation after the heat cycle test can be controlled to be extremely small.

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

[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 a main part showing the structure of the roof trim for the automobile, and FIGS. 3 to 8 are the methods of the present invention. FIG. 9 is a sectional view showing the respective steps, and FIG. 9 is a sectional view showing the principal part of another embodiment of the automobile roof trim manufactured by applying the method of the present invention.

1 and 2, an automobile roof trim 10 has a recess 10a for accommodating a passenger side sun visor and a passenger side sun visor on the front side.
And the recesses 10b for accommodating the assist grips are formed at three positions on the passenger seat side and both sides of the rear seat occupant.

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

More specifically, the foamed PPO core material 20 described above.
Is a structure in which the PPO resin skin layers 22 are integrally formed on the front and back surfaces of the PPO resin foam layer 21, and the PPO resin in the present embodiment is not pure PPO, and polystyrene is added in consideration of cost and the like. , I am using a modified one.

As specific numerical values, the weight of the PPO resin foam layer 21 is 500 to 600 g / m ² , and the thickness of the PPO resin skin layer 22 is 0.18 mm.
Cold press after softening a PO resin base material with a total thickness of 3.5 mm to 130 to 140 ° C. in the heating step described later to expand the total thickness of the PPO resin base material to 6 to 8 mm. Foamed PPO core material 2 by molding
0 thickness is 2 to 3 mm at the edge, 6 m at the general part
The one set to m is used.

On the other hand, as the skin material 30, a cloth having a hot melt film 32 laminated on the back surface of the cloth 31 is used. 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 polyurethane foam may be inserted between the two in order to enhance cushioning properties.

By the way, 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 these edge portions 12, 13 can be deformed after the heat cycle test. It is an object of the present invention to provide a molding method that can easily provide the roof trim 10 that has a good appearance and is excellent in the positioning accuracy with respect to a counterpart component by suppressing it as much as possible.

That is, as shown in FIG. 2, the folded-back portion 1 extends along the front edge 12 of the roof trim 10.
Although not shown, 1 is folded back to the back side of the product and firmly bonded and fixed by a general-purpose adhesive such as a urethane adhesive or an acrylic adhesive, which is not shown.

Since the folded-back portion 11 is solid and has no restoring force unlike the general portion of the foamed PPO core material 20, the folded-back portion 11 can be folded back smoothly and the folded-back workability is improved. In addition, since the unevenness due to heat welding does not occur unlike the conventional case, deformation such as meandering occurring after the heat cycle test does not occur, a sharp edge shape is secured, and the design is extremely excellent.

Next, a method of solidifying the folded-back portion 11 along the edge portions 12 and 13 of the roof trim 10 in this manner will be described in detail with reference to FIGS. 3 to 8.

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

Then, the expanded P in the expanded state is placed in the press die.
The PO core material 20 and the skin material 30 are set. First, the schematic configuration of the press die will be described. This press die includes a cold press forming lower die 50 and a cold press, each of which has a curved die surface. An upper molding die 60, and hot press dies 70 and cold press dies 80 alternately arranged on a part of the outer peripheries of the cold press upper and lower dies 50, 60 (front side edge and rear side edge). It is composed of and.

More specifically, the cold press molding upper die 60 is configured to be vertically movable by a predetermined stroke by a lifting cylinder 61, and the hot press die 70 is mounted on the upper plate 62 of the cold press molding upper die 60. It is supported by a mounted cylinder 71 so as to be able to move up and down by a predetermined stroke. Similarly, in the hot press die 70 installed in the lower die 50, it is also supported by a cylinder 71 attached to the lower plate 51 so that it can be raised and lowered by a predetermined stroke. There is.

The cold press dies 80 are located outside the hot press dies 70, and the upper plate 6
2, the hot press die 70 installed in the upper die 60 is provided so as to be able to move forward and backward by the cylinder 81 attached to the lower plate 51, and then the upper die 60 is evaded.
Of the lower mold 5
After the hot press die 70 of 0 is moved down, it is moved to the position where it comes into contact with the side wall surface of the lower die 50 by the operation of the cylinder 81.

Then, as shown in FIG. 4, when the cold press upper and lower molds 50 and 60 are in the mold open state, the expanded PPO core material 20 and the skin material 30 which are in the expanded state through the preheating step are put into the upper and lower molds. Set within 50, 60.

At this time, the hot press die 70 is stretched by the cylinder 71, respectively.
The mold surface of is positioned substantially flush with the mold surfaces of the cold press molding upper and lower molds 50, 60.

A polyester fiber non-woven fabric 72 is attached 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 cold press molding upper die 60 performs a predetermined stroke lowering operation by the operation of the lifting cylinder 61, and the cold press molding upper and lower dies 50, 60 cause the foamed PPO core material 20 and The skin material 30 is integrally formed in a required shape.

Upper and lower molds 50, 6 for cold press molding
The mold temperature of 0 is 60 ° C, and the pressure is 1.6 kg / c for about 20 seconds.
Cold press molding is performed with a press pressure of m ² .

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

Then, as shown in FIG. 6, as the upper die 60 rises, the hot press die 70 located on the outer periphery of the upper and lower dies 50, 60 is reduced by the cylinder 71 so that the space S is provided above and below the folded portion 11. Is set.

Next, as shown in FIG. 7, the cylinder 81
Is operated, the cold press die 80 enters into this space S, and the cold press die 80 is positioned on the outer periphery of the cold press upper and lower die 50, 60.

Then, the upper and lower molds 5 for cold press molding are used.
The folded portion 11 is forcibly cooled from the upper and lower surfaces of the folded-back portion 11 by 0,60 with a predetermined press condition (pressing time of about 12 to 15 seconds, pressing pressure of about 4.1 kg / cm ² ). Solidified into a thin wall.

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 cold press molding upper and lower molds 50 and 60, and the general portion of the roof trim 10 is The upper and lower molds 50 and 60 for cold press molding are used to draw a desired shape, and the folded portion 11 along the front edge 12 and the rear edge 13 of the roof trim 10 is first formed by the hot press mold 70. A two-step press process of performing hot press molding and then cold press molding with a cold press die 80 can be made into a thin solid body, and the folded-back portion 11 can be easily folded back to the back side, and the adhesive agent With this, reliable adhesion and fixing can be achieved.

Further, since the unevenness due to heat welding is not formed unlike the conventional case, the deformation after the heat cycle test is 0.5 to 5.
It can be suppressed to about 1.0 mm, a sharp edge line can be formed, the appearance of the edge can be kept beautiful, and the alignment accuracy with a mating part such as a garnish can be improved.

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

In such a case, there is an advantage that the folding work of the folding portion 11 can be eliminated and the cost can be reduced due to the reduction of the number of steps.

[0048]

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

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

(2) The method for molding a foamable substrate according to the present invention comprises hot press molding along the edge of the foamable substrate,
Since cold press molding is performed alternately and solidified along the edge of the foamable substrate into a thin wall, it is not necessary to heat weld the edge, unlike the conventional case.
Since the unevenness caused thereby is not formed, the deformation after the heat cycle test is 0.5 to 1
Since it can be suppressed to as small as 1.0 mm, the appearance of the peripheral edge along the edge portion can be significantly improved, and the matching accuracy with the mating component can be improved.

(3) Since the method for molding a foamable base material according to the present invention is to perform cold press molding after hot press molding along the edge portion of the base material, the edge of the foamable base material is Since the part can be solidified in a thin shape, deformation can be suppressed and sufficient rigidity can be obtained, the terminal processing of folding back the edge flange part can be eliminated and the terminal processing work can be simplified. Have.

[Brief description of 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 preheating process of 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 base material in a mold in the method of the present invention.

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

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

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

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

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

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

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.

13 is a view on arrow A in FIG.

[Explanation of symbols]

 10 Automotive Roof Trim 11 Folding Part 12 Front End Edge 13 Rear Side End 20 Foamed PPO Core Material 30 Skin Material 40 Heater Device 50 Cold Press Molding Lower Mold 60 Cold Press Molding Upper Mold 70 Hot Press Mold 72 High melting point fiber non-woven fabric 80 cold press type

Claims (4)

[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 molds (50, 60) for cold press molding, and foamed. The edge portions (12, 1) are formed by performing hot press molding and then cold press molding along the edge portions (12, 13) of the flexible substrate (20).
A method for molding a foamable substrate, characterized in that 3) is solidified into a thin shape. 2. Upper and lower molds (50, 6) for cold press molding
0) on at least part of the outer circumference of the hot press die (7
0) and cold press molds (80) are alternately arranged to form edge portions (12, 13) of the foamable substrate (20).
2. The method for molding a foamable substrate according to claim 1, wherein hot press molding and cold press molding are alternately performed along the line. 3. The mold surface of the hot press mold (70),
The method for molding a foamable substrate according to claim 1, wherein a high melting point nonwoven fabric (72) is attached. 4. The solidified edge portion (12, 1)
3. The method for molding a foamable substrate according to claim 1, wherein 3) is a folded-back portion (11) that is fixed by folding back on the back surface side.