JP2004314889A - Interior component for automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an interior component for automobiles, such as a door trim or a rear side trim, reduced in weight and cost and, in addition, prevented from breaking and undergoing flexural deformation in a designed rugged part. <P>SOLUTION: A door trim 10 for an automobile is constructed by integrating a resin rib 30 to the backside of a foamed resin substrate 20 having light weight and a shape retaining property. The resin rib 30 comprises an outer peripheral rib 31 and a rigid rib 32 along graining grooves or the like. In particular, for the designed rugged part A of a product, a reinforcing plate 33, which is wider than the resin rib 30, is integrated with the backside of the foamed resin substrate 20 to prevent the deformation of the concave-convex part A in the design. The rigidity is further increased by integrating the reinforcing plate 33, the outer peripheral rib 31, and the rigid rib 32 through a connecting rib 34. The rugged part A is molded by utilizing vacuum suction force to enhance the moldability of the wide reinforcing plate 33. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to interior parts for automobiles such as door trims, rear side trims, and luggage trims. In particular, the present invention can reduce the weight, reduce the manufacturing cost, and enhance the rigidity near the clip mounting portion. The present invention relates to an interior part for an automobile that can be mounted smoothly.
[0002]
[Prior art]
For example, a door trim mounted on a side wall panel of a vehicle will be described as an example of an interior part for a vehicle with reference to FIGS. The door trim 1 is configured by laminating and integrating a skin 3 having excellent surface appearance, touch feeling and the like on the surface of a resin core material 2 having shape retention and rigidity for mounting to a vehicle body panel.
[0003]
The resin core material 2 is made of a polypropylene resin mixed with a filler such as talc, while the skin 3 is made of a laminated sheet material in which polyethylene foam is laminated on the back surface of a synthetic resin sheet such as a PVC sheet. Recently, a laminated sheet material in which a polyethylene foam is laminated on the back surface of an elastomer sheet such as a TPO (thermoplastic olefin) sheet tends to be frequently used in consideration of the environment and recycling. In addition, these skins 3 do not have a self-retaining property, and can maintain the shape by sticking to the core material 2.
[0004]
For reference, a method of molding the door trim 1 using the molding die 4 will be briefly described with reference to FIG. When the upper and lower molds 5 and 6 having mold surfaces conforming to the product shape are in the mold open state, the raw sheet of the skin 3 is set, and after the mold is clamped, the cavity is passed from the injection machine 7 through the manifold 6a and the gate 6b. By injecting and filling the molten resin M as a material of the resin core material 2 into C, the resin core material 2 is formed into a desired curved surface shape, and the skin 3 is integrally formed on the surface of the resin core material 2. A molding method which is rich in mass productivity is mainly used (for example, see Patent Document 1).
[0005]
[Patent Document 1]
JP-A-10-138268 (page 2, FIG. 3, FIG. 4)
[0006]
[Problems to be solved by the invention]
However, in the conventional door trim 1, it has been pointed out that the projected area of the resin core material 2 is large, so that the material cost is high and the product is heavy.
[0007]
In addition, since the projected area of the resin core material 2 is large, the injection pressure at the time of molding must be set high, and a mold structure that can withstand the high injection pressure is required. In addition, it has been pointed out that a large amount of molten resin is cooled and solidified, thereby prolonging the molding cycle.
[0008]
Furthermore, since the skin 3 is based on a non-breathable synthetic resin sheet, it has also been pointed out that the sound absorbing performance is inferior and the sound absorbing property against vehicle interior noise cannot be expected.
[0009]
SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and it is possible to promote weight reduction, reduce costs, increase rigidity of a curved surface portion, and maintain good design for a long period of time. The purpose is to provide parts.
[0010]
[Means for Solving the Problems]
The inventor of the present invention has conducted intensive studies to solve the above-mentioned problems. As a result, the foamed resin sheet, which has been conventionally used as a skin material, is given a shape-retaining property, thereby imparting a function as a core material and having a rigidity. The present invention has been completed by appropriately arranging resin ribs where necessary, and adopting a reinforcing structure particularly at locations corresponding to the design irregularities.
[0011]
That is, the automotive interior part according to the present invention is a vehicle interior composed of a lightweight and shape-retaining foamed resin base material and a resin rib having a predetermined pattern integrated with the back surface of the foamed resin base material. In the component, a reinforcing plate body wider than the resin rib is laminated and integrated on the back surface of the foamed resin base material in the design uneven portion of the interior component.
[0012]
Here, as interior parts for automobiles, the present invention can be applied to all interior parts mounted on vehicle body panels via clips, such as door trims, rear parcel shelves, floor trims, luggage trims, trunk trims, and rear side trims. In addition, the design uneven portion refers to a ridge line, a valley line, or the like for making a three-dimensional shape appear on the surface of a product.
[0013]
The foamed resin base material having shape retention properties is formed into a desired curved shape in a molding die after the foamed resin sheet is heated and softened, and the shape is maintained. The term "shape retention" as used herein means that even if there is no reinforcing material such as a rib, when the molded article is released from the mold, it has rigidity enough to maintain its shape. Also, when the product shape includes a high expansion rate, after heating and softening the foamed resin sheet, a vacuum suction mechanism is arranged in the molding die, and vacuum suction is performed along the inner surface of the molding die with a vacuum suction force. A force may be applied.
[0014]
As the foamed resin sheet, a material obtained by adding a foaming agent to a thermoplastic resin is used. Incidentally, the thermoplastic resin may be composed of one kind of thermoplastic resin or two or more kinds of thermoplastic resins. Preferably, polyethylene resin, polypropylene resin, polystyrene resin, polyamide resin, polyacetal resin, polyethylene terephthalate resin, polyvinyl alcohol resin, vinyl chloride resin, ionomer resin, acrylonitrile / butadiene / styrene (ABS) Resin or the like can be used.
[0015]
As the foaming agent, an organic foaming agent such as an azo compound, a sulfohydrazide compound, a nitroso compound, and an azide compound, or an inorganic foaming agent such as sodium bicarbonate can be used.
[0016]
The foamed resin substrate obtained by molding the foamed resin sheet into a required shape after the heat softening treatment has a foaming ratio of 2 to 10 times in consideration of the balance between the weight and the strength of the product. The cell diameter of the foamed resin substrate at that time is preferably in the range of 0.1 μm to 2 mm, and the thickness is preferably 0.5 to 30 mm, and more preferably 1 to 10 mm.
[0017]
On the other hand, the resin rib includes an outer peripheral rib along the outer peripheral edge of the interior component, and a rigid rib corresponding to the rigidity reinforcing portion. The thermoplastic resin material used as the resin rib can be appropriately selected from a wide range of thermoplastic resins. Usually preferably used are polyethylene resin, polypropylene resin, polystyrene resin, polyethylene terephthalate resin, polyvinyl alcohol resin, vinyl chloride resin, ionomer resin, polyamide resin, polyacetal resin, acrylonitrile / butadiene / Styrene (ABS) resin, polycarbonate resin and the like can be used.
[0018]
Various fillers may be mixed in these thermoplastic resins. Examples of the filler that can be used include inorganic fibers such as glass fiber and carbon fiber, and inorganic particles such as talc, clay, silica, and calcium carbonate. Further, various additives such as an antioxidant, an ultraviolet absorber, a coloring agent, a flame retardant, and a low shrinkage agent may be blended.
[0019]
Further, a reinforcing plate body wider than the resin rib is laminated and integrated on the back surface of the foamed resin base material corresponding to the design unevenness portion of the interior part in order to maintain the rigidity of the design unevenness portion. Are integrally formed when the resin rib is formed.
[0020]
According to the automotive interior part of the present invention, the foamed resin base material is lightweight and has shape retention properties, and the resin ribs are laminated and integrated on the back surface side of the foamed resin base material. For the foamed resin base material corresponding to the uneven part, since the reinforcing plate body wider than the resin rib is backed, by eliminating the conventional resin core material with a very large projected area, The weight can be reduced, and the resin material can be saved.
[0021]
Furthermore, the design irregularities of the product are likely to be fulcrums that will break or bend when an external force is applied, but since this part is reinforced by a wide reinforcing plate, it may break or bend and deform. Absent.
[0022]
Next, as a preferred embodiment of the present invention, the foamed resin substrate is formed into a desired curved shape by clamping a molding die, and a portion corresponding to the design uneven portion is incorporated into the molding die. It is characterized by being vacuum formed by a vacuum suction mechanism.
[0023]
According to this embodiment, when forming the design uneven portion on the foamed resin base material, it is possible to form a sharp shape such as a highlight line by vacuum forming, and at this time, the foamed resin sheet is placed on the side of the vacuum suction mechanism. Therefore, the space on the opposite side, that is, the space for the reinforcing plate body can be effectively secured, and the formability of the reinforcing plate body can be improved.
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a preferred embodiment of an interior part for an automobile according to the present invention will be described by exemplifying an automobile door trim.
[0025]
FIG. 1 is a front view showing an embodiment in which an automobile interior part according to the present invention is applied to a door trim, FIGS. 2 and 3 are cross-sectional views showing a configuration of the automobile door trim, and FIG. 4 is a resin in the automobile door trim. FIG. 5 to FIG. 7 are explanatory views showing the manufacturing process of the vehicle door trim for reference, and FIG. 8 shows a modified example of the vehicle door trim to which the present invention is applied. It is explanatory drawing which shows arrangement | positioning of a resin rib and a reinforcement plate body.
[0026]
An embodiment of the present invention will be described with reference to FIGS. 1 to 4, an automobile door trim 10 is laminated and integrated with a lightweight foamed resin base material 20 having a shape-retaining property molded into a desired curved surface shape and a back surface side of the foamed resin base material 20. And a predetermined pattern of resin ribs 30 extending in an intersecting manner.
[0027]
More specifically, a decorating material 21 for imparting decorative properties is laminated on the entire surface of the foamed resin base material 20. Various functional components such as an inside handle escutcheon 11, a power window switch finisher 12, a speaker grille 13, and a pocket escutcheon 14 are attached to the door trim 10.
[0028]
By the way, the foamed resin base material 20 is subjected to heat softening treatment of the foamed resin sheet so as to have shape-retaining properties, then thermoformed into a desired shape, for example, cold-pressed with a molding die having a desired mold surface. Further, the foamed resin base material 20 may be formed into a required shape by vacuum molding at a high expansion rate portion including a design irregularity portion (indicated by a symbol A in FIG. 1). The design irregularities A are ridge lines, valley lines, and the like.
[0029]
The foamed resin sheet has a configuration in which a foaming agent is added to a general-purpose thermoplastic resin. Examples of the thermoplastic resin include a polyethylene-based resin, a polypropylene-based resin, a polystyrene-based resin, a polyamide-based resin, a polyacetal-based resin, and a polyethylene terephthalate-based resin. Resin, polyvinyl alcohol-based resin, vinyl chloride-based resin, ionomer-based resin, acrylonitrile / butadiene / styrene (ABS) resin, etc. can be used. As a foaming agent, an organic foaming agent such as azodicarbonamide or an inorganic foam such as sodium bicarbonate can be used. Blowing agents can be used. In this embodiment, a foamed resin sheet obtained by appropriately adding sodium bicarbonate to a polypropylene resin is used. The expansion ratio of the foamed resin base material 20 is set to 2 to 10 times, and the thickness is set to 0.5 to 30 mm, particularly 1 to 10 mm.
[0030]
Next, the resin rib 30 is formed of a general-purpose synthetic resin molded body, and as a synthetic resin that can be preferably used, a polyethylene resin, a polypropylene resin, a polystyrene resin, a polyethylene terephthalate resin, a polyvinyl alcohol resin, a vinyl chloride resin , An ionomer-based resin, a polyamide-based resin, a polyacetal-based resin, an acrylonitrile / butadiene / styrene (ABS) resin, a polycarbonate resin, or the like. In the present embodiment, the polypropylene-based resin is used in consideration of the environment and recycling. Is used.
[0031]
In addition, fillers such as inorganic fibers such as glass fibers and carbon fibers and fillers such as inorganic particles such as talc, clay, silica and calcium carbonate are mixed into the thermoplastic ribs. May be.
[0032]
Further, the resin rib 30 is roughly constituted by an outer peripheral rib 31 along the outer peripheral edge of the door trim 10 and a rigid rib 32 provided at a place where rigidity is required, such as the wood grain groove 15 and the armrest 16. A mounting seat for mounting the inside handle escutcheon 11, the power window switch finisher 12, the speaker grille 13, the pocket escutcheon 14, and the like may be provided integrally with the rigid rib 32.
[0033]
As described above, the door trim 10 is constituted by the foamed resin base material 20 having shape-retaining properties and the resin ribs 30 laminated and integrated on the back surface of the foamed resin base material 20, so that the door trim 10 Since the resin core material occupying the entire surface can be eliminated and the use of the lightweight foamed resin base material 20, the weight of the product can be reduced by 40% or more as compared with the conventional example. In addition, the resin material can be largely saved, and the cost can be reduced.
[0034]
Furthermore, since the foamed resin base material 20 has a porous structure, the door trim 10 has excellent sound absorbing performance and can reduce noise in the vehicle interior. Further, in order to maintain the sound absorbing property of the foamed resin base material 20, the decorative material 21 laminated and integrated on the surface of the foamed resin base material 20 is a sheet having air permeability such as a woven fabric, a nonwoven fabric, and a knitted fabric. Materials are preferred. The decorative material 21 may be made of a synthetic resin sheet such as PVC or TPO (thermoplastic olefin), or a cushion such as polyethylene foam on the back surface of the synthetic resin sheet, in addition to a breathable sheet such as a woven fabric, a nonwoven fabric, or a knitted fabric. A laminated sheet in which layers are laminated, a synthetic resin film, a foam, a net, and the like can be used.
[0035]
In addition, in the present invention, the reinforcing plate body 33 that is integrated with the resin rib 30, particularly the rigid rib 32, and is wider than the resin rib 30 particularly corresponds to the design uneven portion A of the door trim 10. It is a structural feature that it is laminated and integrated on the back surface of.
[0036]
Therefore, since the rigidity is strongly maintained by the reinforcing plate body 33, even when an external force is applied to the design uneven portion A in the door trim 10, the design uneven portion A becomes a base point and breaks (indicated by a dotted line in FIG. 2). Alternatively, the initial shape can be maintained for a long period of time without inducing bending deformation.
[0037]
Next, an outline of a manufacturing process of the door trim 10 will be briefly described with reference to FIGS. First, as shown in FIG. 5, the one obtained by laminating the decorative material 21 on one surface of the foamed resin sheet S by the heater device H is heated and softened to a predetermined temperature.
[0038]
As the foamed resin sheet S, a polypropylene foamed sheet (manufactured by Sumika Plustech Co., Ltd., trade name: Sumicellar foamed PP sheet, foaming ratio = 3 times, thickness 3 mm) is used.
[0039]
Then, as shown in FIG. 6, the foamed resin sheet S (on which the decorative material 21 is laminated) subjected to the heat softening treatment is set in a molding die 40. The configuration of the molding die 40 includes a molding upper die 41 capable of moving up and down by a predetermined stroke, a fixed lower molding die 42 paired with the molding upper die 41, and an injection machine 43 connected to the molding lower die 42. It is roughly composed of
[0040]
More specifically, the upper molding die 41 is formed with a cavity 411 conforming to the product shape, and is driven up and down by a predetermined stroke by an elevating cylinder 412 connected to the upper surface of the upper molding die 41. At four corners of the upper mold 41, guide bushes 413 serving as a guide mechanism are provided.
[0041]
On the other hand, the lower molding die 42 is provided with a core portion 421 corresponding to the cavity portion 411 of the upper molding die 41. Further, a manifold 422 and a gate 423 are provided to supply the molten resin to the mold surface of the core portion 421. The molten resin M supplied from the injection machine 43 through the resin passage of the manifold 422 and the gate 423 is provided. Is filled in the groove 424 and the recess 425 formed on the upper surface of the core 421.
[0042]
At four corners of the lower mold 42, guide posts 426 serving as a guide mechanism are protruded. The guide posts 426 are guided into the guide bush 413 when the upper and lower molds 41 and 42 are clamped. Thus, the pressing posture of the upper mold 41 can be properly maintained. The groove 424 corresponds to the outer peripheral rib 31 and the rigid rib 32 in the resin rib 30, and the concave portion 425 corresponds to the wide reinforcing plate body 33.
[0043]
Further, in the present embodiment, a vacuum suction mechanism 44 is locally provided in the upper molding die 41 corresponding to the concave portion 425 of the lower molding die 42. The vacuum suction mechanism 44 has a plurality of vacuum suction holes, and includes an insert 441 that is fitted and fixed to the upper mold 41 and a vacuum suction pipe 442 that communicates with the insert 441 and connects to a vacuum pump (not shown). Have been. The point at which the vacuum suction force is applied does not need to be limited to only the design irregularities A of the product, and may be provided on the entire surface of the product. In order to enhance the vacuum forming performance, it is preferable to use a non-breathable TPO sheet or a laminated sheet in which polyethylene foam is laminated on the back surface of the TPO sheet as the decorative material 21 to be laminated on the foamed resin sheet S. good.
[0044]
Then, after setting the foamed resin sheet S in the upper and lower molds 41 and 42, the elevating cylinder 412 of the upper mold 41 is operated, and the upper mold 41 is lowered by a predetermined stroke, as shown in FIG. The upper and lower molds 41 and 42 are clamped to form the foamed resin sheet S along a desired mold surface shape, and the foamed resin base material 20 in the design irregularities A of the product is favorably formed by the vacuum suction mechanism 44. Is shaped.
[0045]
At the same time, in order to form the resin ribs 30 (outer peripheral ribs 31 and rigid ribs 32) and the wide reinforcing plate body 33 from the injection machine 43 through the manifold 422 and the gate 423, the molten resin M is clamped to the upper and lower molds 41 and 42. It is injected and filled into the groove 424 and the recess 425 either before or after the mold clamping. Therefore, the door trim 10 can be easily manufactured by one press of the molding die 40.
[0046]
Next, FIG. 8 shows a modified example of the present invention. As described above, in the door trim 10, the foamed resin base material 20 is removed in the state shown in FIG. Only the relationship between the resin rib 30 and the reinforcing plate body 33 is shown, but for the reinforcing plate body 33 provided corresponding to the design irregularities A of the product, the outer peripheral rib 31 and the rigid rib 32, The resin ribs 30 and the reinforcing plate 33 are firmly integrated via the connecting ribs 34.
[0047]
Therefore, although the amount of the resin material is slightly increased, the amount of the resin can be reduced as compared with the conventional resin core material, the weight and cost can be reduced, and the shape maintaining function is much stronger than that of the above-described embodiment. Can be provided.
[0048]
It is not necessary to limit the interior parts of the present application to the above-described manufacturing method. If necessary, after forming a heat-softened foamed resin sheet in advance, the outer peripheral rib 31, the rigid rib 32, and the connection are formed by another injection or stamping mold. The ribs 34 and the reinforcing plate body 33 may be formed, or the molded foamed resin base material 20 and the molded peripheral ribs 31, the rigid ribs 32, the connecting ribs 34, and the reinforcing plate body 33 may be reduced in weight. It is possible to manufacture a product having the characteristics shown in the present embodiment using the manufactured product.
[0049]
【The invention's effect】
As described above, the automotive interior part according to the present invention is an automobile interior part obtained by laminating and integrating resin ribs on the back surface of a lightweight, shape-retaining foamed resin base material. In order to strengthen the rigidity on the back side of the foamed resin base material with respect to the irregularities, it is a configuration that integrates a wide reinforcing plate body, so that the conventional heavy resin core material can be eliminated, light weight and low cost Therefore, the present invention has an effect of being able to provide an automobile interior part having excellent sound absorbing performance.
[0050]
Furthermore, the interior parts for automobiles according to the present invention are designed such that the rigidity of the design irregularities is enhanced by the wide reinforcing plate body on the back surface of the design irregularities, so that even when external force is applied, the design irregularities are the starting points. This has the effect that the initial shape can be favorably maintained for a long period of time without breaking or bending deformation.
[0051]
Further, the interior parts for automobiles according to the present invention, when forming the design irregularities, enhance the formability of the design irregularities by applying a vacuum suction force at least in the design irregularities, and filling space of the reinforcing plate body. By assuring with a vacuum suction force, there is an operational effect that good molding performance can be obtained.
[Brief description of the drawings]
FIG. 1 is a front view showing an embodiment of an automobile door trim to which the present invention is applied.
FIG. 2 is a sectional view taken along line II-II in FIG.
FIG. 3 is a sectional view taken along line III-III in FIG.
FIG. 4 is an explanatory view showing a relationship between a resin rib and a reinforcing plate body when a foamed resin base material in the automotive door trim shown in FIG. 1 is removed.
FIG. 5 is an explanatory view showing a heating step of the foamed resin sheet in the method of manufacturing the automobile door trim shown in FIG.
FIG. 6 is an explanatory view showing a step of setting a foamed resin sheet in a molding die in the method for manufacturing the automobile door trim shown in FIG. 1;
FIG. 7 is an explanatory diagram showing a door trim forming step in the method of manufacturing the automobile door trim shown in FIG.
FIG. 8 is a view showing a modified example of a door trim for an automobile to which the present invention is applied, and is an explanatory view showing a relationship between a resin rib from which a foamed resin base material is removed and a reinforcing plate body.
FIG. 9 is a front view showing a conventional automobile door trim.
FIG. 10 is a sectional view taken along line XX in FIG. 9;
FIG. 11 is an explanatory view showing an outline of a manufacturing process of a conventional automobile door trim.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Car door trim 11 Inside handle escutcheon 12 Power window switch finisher 13 Speaker grill 14 Pocket escutcheon 15 Wood grain groove 16 Armrest 20 Foam resin base material 21 Decorating material 30 Resin rib 31 Outer peripheral rib 32 Rigid rib 33 Reinforcement plate body 34 Connecting rib 40 Molding die 41 Molding upper mold 42 Molding lower mold 424 Groove (for resin rib molding)
425 recess (for molding a reinforcing plate)
43 Injection machine 44 Vacuum suction mechanism 441 Insert 442 Vacuum suction pipe S Foamed resin sheet M Molten resin A Design irregularities

Claims (3)

An automotive interior component (10) comprising a lightweight and shape-retaining foamed resin base material (20) and a predetermined pattern of resin ribs (30) integrated with the back surface of the foamed resin base material (20) )
The design uneven portion (A) of the interior part (10) has a reinforcing plate body (33) wider than the resin rib (30) laminated and integrated on the back surface of the foamed resin base material (20). Characteristic automotive interior parts. The automotive interior part according to claim 1, wherein the reinforcing plate (33) is formed continuously with the resin rib (30). The foamed resin base material (20) is formed into a desired curved surface shape by clamping the molding die (40), and a portion corresponding to the design irregularities (A) is incorporated into the molding die (40). The interior part for an automobile according to claim 1 or 2, wherein the interior part is formed by vacuum forming by a vacuum suction mechanism (44).

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