JP2022134716A - Method for manufacturing foam-molded product - Google Patents

Abstract

To provide a method capable of reducing a manufacturing cost of a foam-molded product having an opening.SOLUTION: A method for manufacturing a foam-molded product uses a foaming mold apparatus 5 having a lower mold 10, an upper mold 20, and a tubular trim blade 31b accommodated in an annular gap 17 opening on a mold surface 10a of the lower mold 10. The method for manufacturing a foam-molded product comprises a setting step, a foam-molding step and a trimming step, and is configured in that: a preformed skin 3 is set on the mold surface 10a of the lower mold 10, and a preformed core material 2 is set on a mold surface 20a of the upper mold 20 in a state where the trim blade 31b is retracted from the mold surface 10a of the lower mold 10; in a mold-clamping state, a foam layer 4 is formed by injecting and foaming a foaming raw material into a foam-molding space 6 between the core material 2 and the skin 3; and furthermore, in the mold-clamping state, the skin 3, the foam layer 4 and the core material 2 of a foam-molded product 1 are cut in this order by making the trim blade 31b project from the mold surface 10a of the lower mold 10, and an unnecessary part A of the foam-molded product 1 surrounded by the trim blade 31b is trimmed. Thus, the foam-molded product 1 having an opening 1a is obtained.SELECTED DRAWING: Figure 4

Description

TECHNICAL FIELD The present invention relates to a method for obtaining a foam-molded product comprising a laminate of a core material, a foam layer and a skin and having openings.

A vehicle instrument panel (foam molded product; hereinafter abbreviated as instrument panel) is constructed by laminating a core material, a foam layer, and an outer skin. A general instrument panel manufacturing process is briefly described as follows. A preformed skin is set on the mold surface of the first mold of a foaming mold device, and a preformed core material is set on the mold surface of the second mold. Then, the foaming raw material is injected into the foaming molding space between the core material and the skin while the molds are clamped, and foamed to mold the foaming layer. As a result, an instrument panel is obtained in which the core material, the foam layer and the skin are laminated. Next, the foam-molded instrument panel is taken out from the foam mold device, and an unnecessary portion corresponding to the opening is trimmed with a trim blade in order to form an opening corresponding to the outlet of the side register, for example.
In the above instrument panel manufacturing method, the foaming process and the trimming process are performed separately using different devices, so the production efficiency is low and the equipment cost is high.

Patent Literature 1 discloses an instrument panel manufacturing method using a foam mold device having a trimming function. Briefly, an annular space is formed in the first mold of the foaming mold apparatus, and a movable member having a mold surface is arranged in this annular space. The leading edge of this movable member is provided as an annular trim blade.

In the foaming mold device of Patent Document 1, the skin is set in the first mold, and the core material is set in the second mold. In this setting process, the mold surface of the movable member is connected to the mold surface of the first mold, and the skin is set so as to contact the mold surfaces of the movable member and the mold surface of the first mold. The core has an opening with a peripheral edge of the opening facing the trim blade.

When the mold is clamped, the periphery of the opening of the core material contacts the skin. As a result, a foam-molding space is formed between the core material and the outer skin on the outer side of the peripheral portion (the radially outer side of the opening). A foam layer is formed by injecting a foam raw material into the foam molding space and foaming it.
By moving the movable member toward the second mold after foam molding, the annular trim blade reaches the ridge of the core material, and in this process, the unnecessary part of the skin (the part corresponding to the opening of the core material) is removed. trimmed.

JP 2014-159127 A

In the method of manufacturing a foam-molded article such as an instrument panel disclosed in Patent Document 1, when molding the core material in advance, it is necessary to form openings corresponding to unnecessary portions of the skin, which increases molding costs. In addition to the trim blade, the movable member has a mold surface that cooperates with the mold surface of the lower mold to support the outer skin, which greatly limits the shape of the foam-molded product that can be manufactured.

The present invention has been made to solve the above problems, and in a method for manufacturing a foamed molded product, a first mold, a second mold, and an annular gap opening to the mold surface of the first mold are filled with the mold surface. Using a foaming mold device equipped with a cylindrical trim blade that is retractable from the
With the trim blade retracted from the mold surface of the first mold, the preformed skin is set on the mold surface of the first mold, and the preformed core material is placed on the mold surface of the second mold. a setting process for setting;
In a state where the first mold and the second mold are clamped, a foaming raw material is injected into the foam molding space between the core material and the skin and foamed to form a foam layer, thereby forming the core material and the skin. A foam molding step of obtaining a foam molded product by laminating the foam layer and the skin;
In the mold clamping state, the trim blade protrudes from the mold surface of the first mold to cut the skin, the foam layer and the core material of the foam-molded product in this order, thereby enclosing the trim blade. a trimming step of trimming unnecessary portions of the foam molded product;
characterized by comprising

According to the above method, since the foam molding and the trimming for forming the openings in the foam molded product can be performed in the foam mold apparatus, the manufacturing cost of the foam molded product having the openings can be reduced. Moreover, when trimming the unnecessary part corresponding to the opening, the trim blade cuts the skin, the foam layer and the core material, so there is no need to form the opening corresponding to the unnecessary part when molding the core material. can be reduced. In addition, since the trimming blade has a cylindrical shape and does not have a mold surface for supporting the skin, the shape of the foam-molded product is not greatly restricted.

Preferably, an annular receiving groove is formed in the mold surface of the second mold at a position corresponding to the trimming blade, and the tip edge of the trimming blade enters the receiving groove in the trimming step.
According to the above method, the trim blade can reliably cut the core material.

Preferably, the core member has an annular thinned portion corresponding to the trim blade.
According to the above method, the core material can be cut with a relatively small force.

Preferably, a notch is locally formed in the tip edge of the trim blade, and in the trimming step, a portion corresponding to the notch is left uncut in the thin-walled portion of the core material. The foam-molded article and the unnecessary portion are connected via the portion that is not cut.
According to the above method, when the mold is opened after trimming to take out the foam-molded product, the unnecessary parts can be taken out together, and it is possible to reliably prevent the unnecessary parts from remaining in the foam mold apparatus.

According to the method of the present invention, it is possible to reduce the manufacturing cost of a foam molded article having openings. In addition, the method of the present invention can be applied without major restrictions on the shape of the foam molded product.

1 is a vertical cross-sectional view of a key part of a foaming mold device according to an embodiment of the present invention, showing a state in which a core material and a skin are set in the foaming mold device and the molds are clamped. FIG. 4 is a vertical cross-sectional view of the main parts of the same foaming mold apparatus, showing a state in which unnecessary parts are trimmed by moving the trim blade after molding the foaming layer. It is a schematic side view which shows the same trim blade. (A) to (D) are enlarged cross-sectional views of essential parts for sequentially explaining steps of manufacturing a foam-molded product by the same foam mold apparatus.

An embodiment of the present invention will be described below with reference to the drawings. In this embodiment, an instrument panel 1 (foam molded product; hereinafter abbreviated as instrument panel) shown in FIG. 4(D) is manufactured. An instrument panel 1 has a core material 2, a skin 3, and a foam layer 4 interposed between the core material 2 and the skin 3 to form a laminated structure. The instrument panel 1 has, for example, a small opening 1a at a position corresponding to the outlet of a side register for air conditioning.

As shown in FIG. 1, a foaming mold device 5 for manufacturing the instrument panel 1 includes a lower mold 10 (fixed mold, first mold) and a mold that is movable in the vertical direction (contact and separation directions) with respect to the lower mold 10. It has an upper mold 20 (movable mold, second mold). The lower mold 10 and the upper mold 20 respectively have mold surfaces 10a and 20a facing each other.

The lower mold 10 has a lower mold main body 11 , a cylindrical housing 12 inserted and supported in a mounting hole 11 a of the lower mold main body 11 , and a lid 13 closing the upper end opening of the housing 12 . The housing 12 has a flange portion 12 a protruding radially inward at its lower end portion, and the flange portion 12 a is fixed to the lower surface of the lower die main body 11 via an annular connecting member 14 . The lid 13 is fixed to an intermediate member 15 , and the intermediate member 15 is supported by a flange portion 12 a of the housing 12 via a plurality of struts 16 . These struts 16 extend in the moving direction of the upper die 20 .

The upper surfaces of the lower mold main body 11 , the housing 12 and the lid 13 (surfaces facing the upper mold 20 ) cooperate to form a mold surface 10 a of the lower mold 10 . An annular space 17 is formed between the inner peripheral surface of the upper end portion of the housing 12 and the outer peripheral surface of the lid 13 . An annular receiving groove 21 is formed in the mold surface 20 a of the upper mold 20 so as to face the annular gap 17 .

The foaming mold device 5 further has a trim mechanism 30 . The trim mechanism 30 has a movable member 31 housed in the housing 12 and a drive section 35 such as a cylinder for moving the movable member 31 . The movable member 31 has a base portion 31a and a cylindrical trim blade 31b extending upward from the peripheral edge of the base portion 31a. The support 16 of the lower die 10 penetrates through the base 31 a of the movable member 31 . The base portion 31 a is connected to the driving portion 35 via the connector 32 .

The trim blade 31b is inserted into the annular gap 17 of the lower die 10. As shown in FIG. The inner circumference of the upper edge (tip edge) of the trim blade 31b is tapered so as to widen upward, so that the upper edge of the trim blade 31b has a sharp cross-sectional shape. As shown in FIG. 3, one notch 31x is formed in a portion of the upper edge of the trim blade 31b. The edge of this notch 31x also has a sharp cross-sectional shape.

A method of manufacturing the instrument panel 1 performed by the foaming mold device 5 having the above configuration will be described.
Forming process of core material and skin
The core material 2 of the instrument panel 1 is injection molded into a predetermined shape, and the skin 3 is molded into a shape corresponding to the core material 2 by the powder slush method.
Set process
As shown in FIGS. 1 and 4A, the molded skin 3 is set in contact with the mold surface 10a of the lower mold 10, and the molded core material 2 is in contact with the mold surface 20a of the upper mold 20. is set in this way. The core member 2 has an annular thin portion 2a corresponding to the receiving groove 21 formed in the mold surface 20a of the upper mold 20. As shown in FIG. The movable member 31 is in the retracted position, and the upper edge (tip edge) of the trim blade 31b is at the same height as or lower than the mold surface 10a of the lower mold 10. As shown in FIG.

Mold Clamping Step Next, the upper mold 20 is lowered and clamped to the lower mold 10 . In this clamped state, a foam molding space 6 is formed between the skin 3 and the core material 2 .
Foam molding process
Next, as shown in FIG. 4B, a foaming raw material (for example, polyol and isocyanate) is injected from the upper mold 20 into the foam molding space 6, and the foaming raw material is foamed to form a foam layer 4 (for example, urethane) is molded. As a result, the instrument panel 1 having a laminated structure composed of the core material 2, the skin 3 and the foam layer 4 is obtained. In this instrument panel 1, the portion surrounded by the gap 17, the trim blade 31b, the receiving groove 21, and the thin portion 2a of the core material 2 is an unnecessary portion A to be trimmed to form the opening 1a.

Trimming process Next, as shown in FIGS. 2 and 4C, the movable member 31 is lifted by the drive unit 35, the upper edge of the trim blade 31b protrudes from the mold surface 10a of the lower mold 10, and the upper mold 20 is trimmed. It enters into the ring-shaped receiving groove 21 . During this rising process, the skin 3, the foam layer 4, and the core material 2 located on the periphery of the unnecessary portion A are cut in this order. Since the core material 2 made of a resin material having relatively high rigidity is cut at the thin portion 2a, it can be cut smoothly with a small force.

As shown in FIG. 3, a notch 31x is formed in one portion of the upper edge of the trim blade 31b. do not disconnect. Therefore, the unnecessary portion A is not completely separated from the instrument panel 1, and is connected to the instrument panel 1 through the portion not cut at the thin portion 2a.

Mold Opening/Ejecting Process Next, the upper mold 20 is raised to open the mold, and the instrument panel 1 is ejected from the mold surface 10a of the lower mold 10 by the eject mechanism provided in the lower mold 10. FIG. When the instrument panel 1 is taken out from the foaming mold device 5, the unnecessary part A connected to the instrument panel 1 can be taken out together. Therefore, it is possible to reliably prevent the unnecessary portion A from remaining in the foaming mold device 5 .

Next, the unnecessary portion A is removed from the instrument panel 1 taken out from the foaming mold device 5 . Since the unnecessary portion A is connected to the instrument panel 1 only at one point of the thin portion 2a of the core member 2, it can be easily separated by hand. Thus, an instrument panel 1 having a small opening 1a is obtained.

The present invention is not limited to the above embodiments, and various other aspects are possible.
In the above embodiment, one trim mechanism was described for convenience of explanation, but a foam mold device may be provided with a plurality of trim mechanisms to manufacture a foam molded product having a plurality of openings.
The notch at the tip edge of the trim blade may be sized to leave not only the thin part of the core material but also the foam layer, or the size to leave both the foam layer and the skin, or make a shallow cut in the thin part of the core material. may be sized to form A plurality of notches may be provided. The annular receiving groove may be interrupted at a location corresponding to the notch.
The unnecessary portion A may be completely separated from the instrument panel 1 in the trimming process without forming a notch in the tip edge of the trim blade.
The trim mechanism may be provided on a movable type.
The present invention can be applied not only to the instrument panel of a vehicle, but also to the manufacture of a foam molded product having a relatively small opening.

INDUSTRIAL APPLICABILITY The present invention can be applied to the production of foam molded articles such as instrument panels.

1 Instrument panel (foam molding)
2 core material 2a thin portion 3 skin 4 foam layer 5 foam mold device 6 foam molding space 10 lower mold (first mold)
10a mold surface 17 annular gap 20 upper mold (second mold)
20a mold surface 21 annular receiving groove 30 trim mechanism 31b trim blade 31x notch 35 drive unit A unnecessary part

Claims (4)

A foaming mold apparatus comprising a first mold, a second mold, and a tubular trim blade housed in an annular gap opening to the mold surface of the first mold so as to be projectable from the mold surface. using
With the trim blade retracted from the mold surface of the first mold, the preformed skin is set on the mold surface of the first mold, and the preformed core material is placed on the mold surface of the second mold. a setting process for setting;
In a state where the first mold and the second mold are clamped, a foaming raw material is injected into the foam molding space between the core material and the skin and foamed to form a foam layer, thereby forming the core material and the skin. A foam molding step of obtaining a foam molded product by laminating the foam layer and the skin;
In the mold clamping state, the trim blade protrudes from the mold surface of the first mold to cut the skin, the foam layer and the core material of the foam-molded product in this order, thereby enclosing the trim blade. a trimming step of trimming unnecessary portions of the foam molded product;
A method for producing a foamed molded product, comprising: Annular receiving grooves are formed in the mold surface of the second mold at positions corresponding to the trimming blades, and a tip edge of the trimming blades enters the receiving grooves in the trimming process. Item 1. A method for producing a foamed molded article according to Item 1. 3. The method of manufacturing a foam-molded product according to claim 1, wherein the core member has an annular thin portion corresponding to the trim blade. A notch is locally formed in the tip edge of the trim blade, and in the trimming step, a portion corresponding to the notch is left uncut in the thin portion of the core material, thereby preventing the cut. 4. The method for manufacturing a foam-molded product according to claim 3, wherein the foam-molded product and the unnecessary portion are connected via a portion.

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