JP2002018919A - Method and apparatus for molding foamable base material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus for molding a foamable base material capable of assuring a uniform foaming level over an entire surface without necessity of a large-scale facility. SOLUTION: The method for molding the foamable base material comprises the steps of arranging a lifter mechanism 60 in a lower mold 40 for mold press molding, primarily pressurizing a foamable resin material M in upper and lower molds 30 and 40 for mold press molding, then forcibly raising the mold 30 at a predetermined stroke by the mechanism 60, effectively assuring a foaming space of the material M, then foam reacting the material, and then secondarily pressurizing in the molds 30 and 40, thereby molding the formable base material 11 having good quality performance without foaming unevenness.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for molding an expandable base material, and enables uniform expansion of the expandable base material without requiring large-scale equipment, thereby reducing the cost. TECHNICAL FIELD The present invention relates to a method and apparatus for forming a foamable base material capable of forming a foamable base material having excellent moldability.

[0002]

2. Description of the Related Art Normally, various interior parts are mounted in a vehicle interior. The configuration of the door trim 1 for an automobile will be described with reference to FIG. 12. The door trim 1 for an automobile has a decorative property and a cushioning property on the surface of a base material 2 having an appropriate shape-retaining property and rigidity for mounting to a vehicle body panel. The base material 2 is made of a resin plate, a fiber plate, or the like, which has been conventionally used as a material of the base material 2. Attention has been paid to foamed substrates.

[0003] By the way, as a method for molding a foamable base material, for example, in the case of a bead foam molded product, a foamable bead material is supplied into a bead molding die, and the foamable bead material is foamed by steam. After cooling, a bead foam molded article having a desired shape is obtained. In the case of a PPO (polyphenylene oxide) substrate, the raw sheet M is heated in a heating furnace 4 as shown in FIG. Then, after being expanded, as shown in FIG. 14, the upper and lower dies 5, 6 for cold press molding are press-molded into a required shape, thereby completing the molding of the foamable base material.

[0004]

As described above, in the conventional molding method and molding apparatus for a foamable base material, for example, in the bead molding method, uneven heating due to steam supply unevenness is likely to occur, and the bead expanded molded body Is inferior in mechanical strength, so that there is a problem that the use is restricted. on the other hand,
In the method of performing cold press molding after pre-heat treatment as in the case of a PPO base material, unevenness in heating is likely to occur in the heating step in the heating furnace 4 and uniform foaming is difficult. It was urgently needed to maintain good results.

The present invention has been made in view of the above circumstances, and provides a method and an apparatus for molding a foamable base material capable of uniformly forming the foamable base material without requiring large-scale facilities. It is intended to be.

[0006]

In order to achieve the above-mentioned object, a foamable base material obtained by distributing and supplying a foamable resin material in a molten state into an upper and lower mold for mold press molding and press-molding into a desired shape. A pressurizing step in which the foaming resin material supplied into the upper and lower molds for mold press molding is spread to all corners of the product cavity by clamping the upper and lower molds for mold press molding; A foaming step of forcibly raising the upper mold for a predetermined stroke to secure a foaming space and foam the foamable resin material.

Further, the present invention relates to a method for forming a foamable base material by distributing and supplying a molten foamable resin material into upper and lower molds for mold press molding and press-molding the same into a desired shape. The first pressurization process that spreads the foamable resin material supplied into the upper and lower molds to the corners of the product cavity by clamping the upper and lower molds for mold press molding, and the upper mold for mold press molding is forced The foaming process is performed by raising the predetermined stroke to secure the foaming space and foaming the foamable resin material, and by lowering the upper mold press mold, forming the foamable base material into the final shape, and cooling. And a secondary pressurizing step.

Here, the foamable base material is used as a core material for interior parts such as door trims, luggage side trims, and roof trims, and has an appropriate shape retention and rigidity for mounting to a vehicle body panel. preferable.

After molding the foamable base material, the skin material may be adhered in a separate step. However, when the upper and lower molds for mold press molding are opened, the skin material is set in advance and the foamable base material is set. At the time of molding the material, the skin material may be integrally attached.

Next, the molding apparatus used in the method of the present invention is a molding apparatus for a foamable base material for press-molding a molten foamable resin material into a desired shape. The upper and lower molds for mold press molding that can form the product cavity of the mold, the injection molding machine that supplies the foamable resin material in the molten state to the product cavity, and the foaming of the foamable resin material arranged in the lower mold for mold press molding It is characterized in that it comprises a lifter mechanism for forcibly lifting the upper mold for mold press molding by a predetermined stroke during molding.

Here, the upper mold for mold press molding can be moved up and down by a predetermined stroke by an elevating cylinder,
A contact / separation operation is performed with respect to the lower mold for mold press molding via a guide mechanism such as a guide post.

An injection molding machine for supplying a foamed resin material in a molten state is connected to the lower mold for mold press molding, and the molten resin material from the injection molding machine is supplied to the lower mold press for molding. It is distributed and supplied to the mold surface of the lower mold for mold press molding through the manifold and gate in the mold.

Further, as a lifter mechanism for forcibly lifting the upper mold press molding die upward by a predetermined stroke when the foamable resin material is foamed, the lifter mechanism is driven to the outer periphery of a product cavity of the lower mold press molding die, for example, at four corners. It is also possible to arrange a push-up post that moves up and down by the use cylinder, and lift the upper die for mold press molding upward by a predetermined stroke by raising the push-up post.

In this case, in the press-pressing step in which the upper mold for mold press molding performs the descending operation, if the cylinder pressure of the drive cylinder of the push-up post is set smaller than the cylinder pressure of the press machine, There is no hindrance to the elevating operation of the upper die for press molding.

Further, by interposing a height adjusting shim between the push-up post and the driving cylinder, the rising stroke of the upper mold for mold press molding can be changed, and the expansion ratio of the expandable resin material can be changed. Can correspond.

Therefore, according to the present invention, after the foamable resin material is spread in the product cavity in the pressurizing step (primary pressurizing step) of the upper and lower molds for mold press molding, the foaming resin material is used in the foaming step. The lifter mechanism forcibly lifts the mold press molding upper die upward by a predetermined stroke,
Since a uniform foaming space can be ensured, a uniform foaming reaction can be performed over the entire surface of the product cavity without causing uneven foaming.

Furthermore, by adopting a simple configuration in which a lifter mechanism such as a cylinder and a post for pushing up is provided in the existing upper and lower molds for mold press molding, the present invention can be carried out without requiring large-scale equipment. In addition, by interposing a height adjusting shim between the push-up post and the drive cylinder, the rising stroke of the upper mold for mold press molding can be varied, and the expansion ratio of the foamable base material can be changed. Can be effectively dealt with.

[0018]

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

FIG. 1 is a front view showing an automobile door trim manufactured by the method of the present invention, FIG. 2 is a cross-sectional view showing the structure of the automobile door trim, and FIG. 3 is an overall apparatus for molding a foamable base material according to the present invention. FIG. 4 is a plan view of a lower mold for mold press molding in the molding apparatus, FIG. 5 is a time chart of an upper mold for mold press molding in the method of the present invention, and FIGS. 6 to 10 are methods of the present invention. FIG. 1 is an explanatory view showing each process in which the process is applied to a molding process of an automobile door trim.
FIG. 1 is a schematic view showing another embodiment of a foaming substrate molding apparatus according to the present invention.

In FIG. 1 and FIG. 2, an automobile door trim 10 is configured by attaching a skin material 12 to the surface of a foamable base material 11. The material of the foamable base material 11 is a foaming agent ( For example, a decomposable foaming agent such as an azo compound or an azide compound can be used, and in this embodiment, a polypropylene (PP) resin mixed with azodicarbonamide is used. In the present embodiment, the skin material 12 is integrally adhered at the time of mold press molding of the foamable base material 11. In addition, as the skin material 12, TP
A laminated sheet material having a good touch and excellent cushioning property, in which a polyethylene foam is lined on the back surface of an O (thermoplastic olefin) sheet, is used.

Further, since the foamable base material 11 is lightweight and excellent in shock absorption, it is preferable in terms of weight reduction of a vehicle and protection of occupants.

Next, the structure of the foaming substrate molding apparatus according to the present invention will be described with reference to FIGS. 3 and 4. The molding apparatus 20 comprises upper and lower dies for mold press molding, which are capable of mutually clamping and opening the mold. An injection molding machine 50 connected to the mold press molding lower mold 40 for supplying the foaming resin material and the mold press molding lower mold 40 are provided. In order to secure a space, the lifter mechanism 60 is roughly constituted by a lifter mechanism 60 that forcibly raises the upper mold 30 for mold press molding by a predetermined stroke.

More specifically, the upper mold 30 for mold press molding can be moved up and down by a predetermined stroke by an elevating cylinder 31, and the lower mold press mold 40 is configured to supply a foamable resin material from an injection molding machine 50. A manifold 41 and a gate 42 are provided as paths.

Also, the upper mold 3 for mold press molding is so fixed that the upper mold 30 for mold press molding can be smoothly guided to the lower mold 40 for mold press molding, and the mold opening can be smoothly guided.
Numeral 0 is supported by guide posts 32 at four corners thereof so as to be movable up and down. The guide posts 32 are inserted into guide holes 43 provided corresponding to the lower mold 40 for mold press molding.

Further, in the molding apparatus 20 according to the present invention, in order to secure a foaming space for the foamable resin material,
A lifter mechanism 60 for forcibly lifting the upper mold 30 for mold press molding by a predetermined stroke is provided. In this embodiment, the lower mold 40 for mold press molding is provided at four corners of the outer periphery of the product cavity C,
Push-up post 61 is lower mold 40 for mold press molding
The push-up post 61 is inserted into the drive cylinder 62 such as a hydraulic cylinder.
And can move up and down a predetermined stroke.

Next, each step of molding the door trim 10 using the molding apparatus 20 will be described with reference to the time chart shown in FIG. 5 and the step explanatory diagrams shown in FIGS. 6 to 10. First, FIG. When the upper and lower molds 30 and 40 for mold press molding are in the mold open state as shown in FIG.

As a means for setting the skin material 12, in addition to using the set pins 33 shown in the figure, a vacuum suction means is disposed on the upper mold 30 for mold press molding, and the skin material 12 is temporarily held by a vacuum suction force. Alternatively, the skin set frame may be arranged on the mold surface of the lower mold 40 for mold press molding.

When the skin material 12 is set, the upper mold 30 for mold press molding is at the upper limit position of A1 in FIG.

Next, as shown in FIG. 7, the upper mold 30 for mold press molding is lowered by a predetermined stroke by driving the cylinder 31 for raising and lowering.
When the clearance between the molds 0 and 40 reaches 10 to 30 mm, the foamable resin material M is distributed and supplied from the injection molding machine 50 to the mold surface of the lower mold 40 for mold press molding through the manifold 41 and the gate 42.

The supply of the expandable resin material M is performed from A2 to A3 in the time chart of FIG. 5, and the time required for the primary pressurization performed from A3 to A4 is about 2 hours. Adjusted between 10 and 10 seconds.

That is, as shown in FIG. 8, in the primary pressurizing step, the expandable resin material M spreads all over the product cavity C.

Thereafter, the upper mold 30 for mold press molding rises from A4 to A5 in the time chart of FIG.
The time required for the foaming process from A5 to A6 is about 5 seconds, and the foamable resin material M performs a foaming reaction.

The lifting operation of the upper mold 30 for mold press molding is performed by the drive cylinder 6 of the lifter mechanism 60.
2, as shown in the time chart of FIG. 5, the hydraulic pressure is turned on at the time of primary pressurization of the upper die 30 for mold press molding, and at this primary pressurization, the upper die 3 for mold press molding is turned on.
Since the cylinder pressure of the lift cylinder 31 of 0 is higher, the primary pressurization state is maintained. However, when the primary pressurization is completed, the hydraulic pressure supplied to the lift cylinder 31 is stopped, as shown in FIG. As described above, the push-up post 61 is raised by the drive cylinder 62 of the lifter mechanism 60 to lift the upper die 30 for mold press molding upward by a predetermined stroke.

Therefore, a space for foaming can be secured over the entire surface of the product cavity C, and the door trim 10
In this case, uniform foaming is performed over the entire foamable base material 11, and uneven foaming does not occur.

Thereafter, in the time chart of FIG. 5, the upper mold 30 for mold press molding descends from A6 to A7, and secondary pressurization is performed from A7 to A8.
In this secondary pressurization, the foamable base material 11 is formed into a final shape and is also cooled, so that the secondary pressurization is performed for about 25 seconds.

The driving cylinder 6 of the lifter mechanism 60
In No. 2, since the oil pressure is maintained in the ON state, the foaming timing can be easily set.

In the secondary pressing step, as shown in FIG. 10, the clearance between the upper and lower molds for mold press molding 30, 40 is larger than that at the time of the primary press, and the upper mold for mold press molding is used. Regarding the lowering operation of 30, the cylinder pressure of the drive cylinder 62 in the lifter mechanism 60 is smaller than the cylinder pressure of the lift cylinder 31.
The lifter mechanism 60 does not hinder the lowering operation of the lower mold 30 for mold press molding.

As described above, in the method of the present invention, the foamable resin material M is subjected to the primary pressurizing step, the foaming step, and the secondary pressurizing step to form a foamable base material having excellent quality performance without uneven foaming. And the upper and lower molds 30 for existing mold press molding,
In addition to 40, a lifter mechanism 60 that lifts the upper mold 30 for mold press molding upward by a predetermined stroke can be provided with a simple configuration. Therefore, there is an advantage that mass production can be performed at low cost without increasing the equipment cost.

When relatively rigidity is not required for the use of the product, the secondary pressurizing step may be omitted.
A foam molded body can be molded in two steps, a pressing step and a foaming step,
Shortening of the cycle can be expected.

FIG. 12 shows another embodiment of the molding apparatus 20. As an improved example of the lifter mechanism 60, a height adjusting shim 63 is provided between a push-up post 61 and a driving cylinder 62. It is interposed.

Therefore, when the expansion ratio of the expandable base material 11 is changed, it is possible to easily respond to the change of the expansion ratio by properly using the height adjusting shim 63 having an appropriate height dimension. it can.

The embodiment described above is applied to the door trim 10 in which the foam material 11 and the skin material 12 are integrally formed by setting the skin material 12 in advance on the upper and lower molds 30 and 40 for mold press molding. After forming only the conductive base material 11 into a required shape, the skin material 12 may be adhered in a later step, and is applied to various trim parts such as a luggage side trim and a roof trim in addition to the door trim 10. You can also.

[0043]

As described above, according to the method and apparatus for molding a foamable base material according to the present invention, a lifter mechanism is incorporated in the upper and lower molds for mold press molding, and the pressurizing step is performed by clamping the upper and lower molds. Thereafter, the upper mold is forcibly raised to foam the foamable resin material, and if desired, the secondary press is performed. Therefore, a foamable base material having a uniform foaming level without foaming unevenness is used. Since molding can be performed with a simple molding apparatus without requiring large-scale equipment, there is an effect that manufacturing costs can be reduced and quality performance of interior parts can be improved.

[Brief description of the drawings]

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

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

FIG. 3 is a schematic view showing an entire configuration of an embodiment of a molding device according to the present invention.

FIG. 4 is a plan view of a lower mold for mold press molding in the molding apparatus shown in FIG. 3;

FIG. 5 is a time chart of an upper mold for mold press molding in the method of the present invention.

FIG. 6 is an explanatory view showing a step of setting a skin material in the method of the present invention.

FIG. 7 is an explanatory view showing a supply step of a foamable resin material in the method of the present invention.

FIG. 8 is an explanatory view showing a primary pressurizing step in the method of the present invention.

FIG. 9 is an explanatory view showing a foaming step in the method of the present invention.

FIG. 10 is an explanatory view showing a secondary pressing step in the method of the present invention.

FIG. 11 is a schematic diagram showing the overall configuration of another embodiment of the foam molding apparatus according to the present invention.

FIG. 12 is a cross-sectional view showing a configuration of an automobile door trim.

FIG. 13 is an explanatory view showing a heating step of the raw foam base material.

FIG. 14 is an explanatory view showing a cold press molding step of a raw foam base material.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 Door trim for automobile 11 Foamable base material 12 Skin material 20 Molding device 30 Upper die for mold press molding 31 Cylinder for elevating 32 Guide post 40 Lower die for mold press molding 41 Manifold 42 Gate 43 Guide hole 50 Injection molding machine 60 Lifter mechanism 61 Post for pushing up 62 Cylinder for driving 63 Shim for height adjustment M Foamable resin material C Product cavity

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) B29L 9:00 B29L 9:00 (72) Inventor Tatsushi Ohno 3316 Miyayama, Samukawa-cho, Koza-gun, Kanagawa Pref. F term in reference (reference) 4F202 AA11 AB02 AD05 AD08 AG03 AG20 AH23 CA11 CB01 CB13 CK11 CL02 CL09 CL12 CQ03 CQ05 4F206 AA11 AB02 AD05 AD08 AG03 AG20 AH23 JA03 JA04 JB13 JF04 JL02 JM02 JM04 JM05 JN33 J83

Claims (5)

[Claims] An upper and lower mold (30, 4) for mold press molding.
A foamable base material (11) obtained by distributing and supplying a foamable resin material (M) in a molten state into 0) and pressing it into a desired shape.
In the molding method of (1), the foamable resin material (M) supplied into the upper and lower molds for mold press molding (30, 40) is closed by closing the upper and lower molds for mold press molding (30, 40). And a foaming step of forcibly raising the upper mold (30) for mold press molding by a predetermined stroke to secure a foaming space and foam the foamable resin material (M). A method for molding a foamable base material, comprising: 2. An upper and lower mold for mold press molding (30, 4).
A foamable base material (11) obtained by distributing and supplying a foamable resin material (M) in a molten state into 0) and pressing it into a desired shape.
In the molding method of (1), the foamable resin material (M) supplied into the upper and lower molds for mold press molding (30, 40) is closed by closing the upper and lower molds for mold press molding (30, 40). ), A primary pressurizing step that spreads to every corner, and the upper mold (30) for mold press molding is forcibly raised by a predetermined stroke to secure a foaming space and foam the foamable resin material (M). A foaming step; and a secondary pressurizing step of lowering the mold press molding upper mold (30) to form the foamable base material (11) into a final shape and cooling the foamable substrate (11). A method for molding a foamable base material. 3. A foaming base material molding apparatus for press-molding a molten foamable resin material (M) into a desired shape, the mold being capable of clamping and opening, and capable of forming a desired product cavity by clamping. Upper and lower dies for press molding (30,
40), an injection molding machine (50) for supplying a foamed resin material (M) in a molten state to the product cavity (C), and a foamable resin material provided in a lower mold (40) for mold press molding. An apparatus for molding a foamable base material, comprising: a lifter mechanism (60) for forcibly lifting a mold press molding upper mold (30) by a predetermined stroke during the foam molding of (M). 4. The foam according to claim 3, wherein the lifter mechanism (60) comprises a push-up post (61) and a drive cylinder (62) for vertically moving the push-up post (61). Molding machine for conductive base material. 5. The lifter mechanism (60) is provided with a height adjusting shim (63) between a push-up post (61) and a driving cylinder (62), thereby forming a foamable resin material (M). 5. The foaming base material forming apparatus according to claim 4, wherein the apparatus is capable of responding to the change of the expansion ratio in the step (1).