JP2007050558A - Interior trimming part for car - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance the appearance capacity of the protruded part of the design surface of a product and to reinforce the rigidity of the protruded part of the design surface of the product in an interior trimming part for a car employing the whole or a part of a laminated structure composed of a foamed resin base material and the resin rib integrated with the back of the base material. <P>SOLUTION: A door trim 10 is constituted of a door trim upper (laminated structure) 20 and a door trim lower (resin single product) 30. The door trim upper 20 is constituted of a laminated structure of the lightweight foamed resin substrate 21 having shape retaining properties and the resin rib 22 integrated with the inner surface of the base material 21. When molding the protruded part 20a of the design surface such as a sharp highlight line or the like formed to the foamed resin substrate 21, an R-part corresponding groove part 424a narrow in width and shallow in depth is set at the place corresponding to the protruded part 20a of the design surface in the groove part 424 of a lower mold 42 to precisely mold the protruded part 20a of the design surface without allowing the foamed resin sheet S to fall in the R-part corresponding groove part 424a. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to automotive interior parts such as door trims, rear parcel shelves, floor trims, trunk trims, luggage trims, roof trims, rear side trims, and the like, and are interior parts for automobiles that are lightweight and have improved exterior design and product rigidity. About.

  For example, the configuration of automobile interior parts will be described with reference to FIGS. 17 and 18 exemplifying door trims. The door trim 1 has shape retention and attachment rigidity to a vehicle body panel, and is configured by laminating and integrating a skin 3 excellent in surface appearance on the surface of a resin core material 2 extending over almost the entire product surface. . The resin core material 2 is made of a polypropylene resin mixed with talc, and the skin 3 does not have shape retention itself, such as polyethylene foam on the back surface of a synthetic resin sheet such as a vinyl chloride sheet. In recent years, considering the environmental and recycling aspects, a cushioning material such as polyethylene foam is provided on the back surface of an elastomer sheet such as a thermoplastic olefin (hereinafter referred to as TPO) sheet. Laminated sheet material tends to be frequently used.

  Next, a conventional example of the method for forming the door trim 1 will be described with reference to FIG. First, a molding die 4 that molds the door trim 1 is connected to a molding upper die 5 that can move up and down by a predetermined stroke, a molding lower die 6 that forms a pair with the molding upper die 5, and a molding lower die 6. It is generally composed of the injection machine 7. Then, when the upper and lower molds 5 and 6 are clamped, a cavity part 5a is formed in the upper mold 5 and a core part 6a is provided in the lower mold 6 in order to form the product shape of the door trim 1. Yes. In order to move the upper molding die 5 up and down by a predetermined stroke, an elevating cylinder 5b is connected, and the molding lower die 6 is provided with a manifold 6b and a gate 6c that serve as a passage for molten resin from the injection machine 7. Further, in order to maintain an appropriate posture, the molding upper die 5 that moves up and down is provided with guide posts 6d at four corners of the molding lower die 6, and the molding upper die 5 corresponds to the guide posts 6d. A bush 5c is provided.

  Therefore, when the molding upper and lower molds 5 and 6 are in the mold open state, the skin 3 is set in the mold, and then the molding upper and lower molds 5 and 6 are clamped and then injected into the product cavity between both molds. By injecting and filling the molten resin M from the machine 7 through the manifold 6b and the gate 6c, the resin core material 2 is formed into a required curved shape, and the skin 3 is integrally formed on the surface of the resin core material 2 (for example, , See Patent Document 1). In FIG. 19, for convenience of explanation, the molten resin M is supplied to the mold surface of the core portion 6a in an open state. However, the molten resin M is injected and filled into the cavity after the upper and lower molds 5 and 6 are clamped. May be.

Japanese Patent Laid-Open No. 10-138268 (Page 2, FIGS. 3 and 4)

  However, in the conventional door trim 1, since the projected area of the resin core material 2 is large, there are problems that the material cost is high and the product is heavy. In addition, since the projected area of the resin core material 2 is large, it is necessary to set the injection pressure at the time of molding high, and a mold structure that can withstand the high injection pressure is required, and the production cost of the mold is increased, In addition, since a large amount of molten resin is cooled and solidified, the molding cycle becomes longer, which is a major factor for reducing productivity.

  The present invention has been made in view of such circumstances, and relates to automotive interior parts such as door trims, and in particular, can promote weight reduction, reduce costs, and improve appearance quality and product rigidity. The purpose is to provide automotive interior parts.

  As a result of earnest research, the present inventors have given the function as a core material by imparting shape retention to the foamed resin sheet that has been used conventionally as the skin, and more. Compared to conventional resin cores with a large projected area, resin ribs with excellent rigidity are placed in places where rigidity is required, that is, peripheral parts of products, panels, parts mounting locations, and parts where loads are applied. By providing a lightweight and inexpensive laminated structure, and by devising the groove shape so that the foamed resin sheet does not fall into the groove provided in the molding die for molding the resin rib, It has been found that molding defects of the foamed resin sheet can be avoided, and the present invention has been completed.

  In order to solve the above-mentioned problems, the present invention comprises a foamed resin base material that is molded into a desired curved surface shape and is lightweight and has shape retention, and a resin rib that is integrated with the back surface of the foamed resin base material. The foamed resin base material is configured such that a foamed resin sheet that has been heat-softened is drawn and molded in a molding upper and lower molds, and a molten resin is injected and filled into a groove portion of a molded lower mold. In an interior part for an automobile in which a laminated structure formed by integrating resin ribs on the back surface of the laminated structure is adopted in whole or in part, a resin rib corresponding to the R portion is provided at a design surface convex portion corresponding to the laminated structure. The rib width of the resin rib corresponding to the R portion is set narrower and the rib depth is shallower than the rib width and rib depth of a general resin rib. It is characterized by avoiding the decline of To.

  Here, the interior parts for automobiles can be applied to door trims, rear parcel shelves, floor trims, trunk trims, luggage trims, roof trims, rear side trims, and the like. The structure of the present invention can be applied to the entire structure of the interior part, and the structure of the present invention is applied to a part of the interior part for an automobile, for example, the door trim upper in the upper and lower divided door trim composed of the door trim upper and the door trim lower. You can also Furthermore, the foamed resin base material used in the present invention can be obtained by molding the foamed resin sheet into a desired curved surface shape after heating and softening the foamed resin sheet, even without a reinforcing material such as a rib. , Has rigidity (shape retention) enough to retain the shape even when removed from the mold.

  As the foamed resin sheet, a material obtained by adding a foaming agent to a thermoplastic resin is used. The thermoplastic resin may be one type of thermoplastic resin or two or more types of thermoplastic resins. Preferably, polyethylene resin, polypropylene resin, polystyrene resin, polyethylene terephthalate resin, polyvinyl alcohol resin, vinyl chloride resin, polyamide resin, polyacetal resin, polycarbonate resin, ionomer resin, acrylonitrile / butadiene / Styrene (ABS) resin or the like can be used. As the foaming agent, an organic foaming agent such as an azo compound, a sulfohydrazide compound, a nitroso compound or an azide compound, or an inorganic foaming agent such as sodium bicarbonate can be used. The foamed resin base material obtained by molding the foamed resin sheet into a required shape after heat softening treatment preferably has a foaming ratio of 2 to 10 times in consideration of the balance between the weight and strength of the product. The cell diameter of the foamed resin base material at that time is preferably in the range of 0.1 μm to 2.0 mm, and the thickness is 0.5 to 30 mm, preferably 1 to 10 mm.

  On the other hand, the thermoplastic resin material used as the resin rib having a reinforcing function can be appropriately selected from a wide range of thermoplastic resins. Usually, those that can be preferably used include polyethylene resins, polypropylene resins, polystyrene resins, polyethylene terephthalate resins, polyvinyl alcohol resins, vinyl chloride resins, polyamide resins, polyacetal resins, polycarbonate resins, ionomer resins, Acrylonitrile / butadiene / styrene (ABS) resin can be used. Moreover, you may mix various fillers 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. Moreover, various additives, such as antioxidant, a ultraviolet absorber, a coloring agent, a flame retardant, and a low shrinkage agent, may be mix | blended.

  The resin rib is generally set to have a rib width of about 3 mm and a rib depth of about 10 mm. However, when the design surface convex portion is provided on the product surface shape of the laminated structure, the design surface convexity is provided. In order to accurately shape the portion, a resin rib corresponding to the R portion is formed at a portion corresponding to the design surface convex portion. The rib width and the rib depth of the R portion corresponding resin rib are set so that the rib width is narrower and the rib depth is shallower than the resin rib of the general portion. For example, the rib width is preferably set to about 2.0 to 2.5 mm, and the rib depth is set to about 3 to 5 mm.

  Furthermore, in order to improve the appearance design, a decorative material may be laminated and integrated on the surface of the foamed resin base material. As this decorating material, a synthetic resin sheet such as a TPO sheet, a thermoplastic plastic urethane (TPU) sheet, a vinyl chloride sheet, or a fabric sheet such as a woven fabric, a nonwoven fabric, a knitted fabric, or a synthetic resin film, a foam, a net-like material, etc. Can be used in the form of a single sheet, or in the form of a laminated sheet material in which a back surface of a synthetic resin sheet or a fabric sheet is lined with a cushion layer such as polyethylene foam, polypropylene foam or polyurethane foam. Although the material which comprises these decorating materials is not specifically limited, It is more preferable to use the raw material which has air permeability, such as a woven fabric, a nonwoven fabric, and a knitted fabric, in order to utilize the sound absorption performance of a foamed resin base material.

  Next, the molding die to be used is a molding die that molds a laminated structure composed of a foamed resin base material that is lightweight and has shape retention, and a resin rib that is integrated on the back surface of the foamed resin base material. The molding die is composed of a molding upper mold and a molding lower mold that can be clamped and opened with each other, and an injection machine that is connected to the molding lower mold and supplies molten resin that is a material of the resin rib. Has been.

  Here, the molding die is composed of a molding upper mold that can move up and down, a molding lower mold that is a fixed side located below the molding upper mold, and an injection machine that is connected to the molding lower mold. . The molten resin supplied from the injection machine is supplied to a groove formed on the mold surface of the molded lower mold through a resin passage such as a manifold and a gate provided in the molded lower mold.

  In addition, the foamed resin sheet is shaped along the shape of the mold surface of the molding die by clamping the molding die. At that time, a heat softening process is performed by a heater or the like before the molding process. The heat-softened foamed resin sheet is set in a molding die. The molding process of the foamed resin sheet by the molding die also includes a cooling process of the foamed resin sheet. The cooling process of the foamed resin sheet includes foaming in addition to cooling by mold clamping of the molding die. The resin sheet may be forcibly cooled. For example, heat may be released by providing a predetermined clearance between the foamed resin base material and the mold surface of the molded lower mold, and coolant such as cooling air is blown from the back side of the foamed resin base material. Thus, the foamed resin base material can be effectively cooled. In this case, the air blow may be performed in a mold-clamped state, or the upper mold is raised so that a clearance is provided between the foamed resin base material and the lower mold, and air is blown into the clearance. Also good.

  In particular, when integrating a resin rib corresponding to the R portion with a narrow rib width and a shallow rib depth on the back surface of the foamed resin base material in the design surface convex portion of the laminated structure, the groove portion of the molded lower mold In order to form the R portion corresponding resin rib, the R portion corresponding groove portion formed in the lower mold is narrower than the groove width of the general groove portion and shallower than the groove depth of the general groove portion. Is set. For example, it is preferable that the groove width is 2.0 to 2.5 mm and the groove depth is 3 to 5 mm.

  Therefore, according to the present invention, it is only necessary to mold the resin rib as compared with the conventional resin core material having a large projected area, so that the injection pressure can be set lower than the conventional one, and the load on the molding upper mold is reduced. Less material is required and material costs can be saved. Furthermore, the R part corresponding resin rib is formed in the back surface of the foam resin base material in the design surface convex part of a laminated structure, The rib width of this R part corresponding resin rib is narrow, and rib depth is set shallowly Therefore, the foamed resin sheet does not fall into the groove portion, and good molding becomes possible. Accordingly, since the resin rib can be set also on the design surface convex portions such as the corner portion and the ridge line, the product rigidity can be enhanced and the appearance performance can be enhanced.

  As described above, according to the automotive interior component according to the present invention, the laminated structure employed in the whole or a part of the automotive interior component is lightweight and has a foamed resin base material having shape retention. Since it is composed of the resin rib integrated on the back surface side, there is an effect that it is possible to provide an interior part that is lightweight, low in cost, and has high rigidity. Furthermore, the R part corresponding resin rib is formed in the back surface of the foam resin base material in the design surface convex part of a laminated structure, The rib width of this R part corresponding resin rib is narrow, and rib depth is set shallowly This prevents the foamed resin sheet from falling into the groove as much as possible, so that appearance defects such as dents do not occur on the design surface protrusions and maintain good appearance performance. In addition, since the structure in which the resin rib is arranged directly below the design surface convex portion is made possible, the product rigidity can be maintained firmly.

  Hereinafter, a preferred embodiment of an automobile interior part according to the present invention will be described by illustrating an automobile door trim. Note that the gist of the present invention is as described in the scope of claims, and the contents of the embodiments described below are merely examples of the present invention.

  FIG. 1 to FIG. 16 show an embodiment of the present invention, FIG. 1 is a front view showing a two-tone type automobile door trim, FIG. 2 is a sectional view showing the configuration of the automobile door trim, and FIG. FIG. 4 to FIG. 6 are cross-sectional views showing the main components of the door trim upper in the automotive door trim, and FIGS. 7 to 10 show the door trim for the automotive trim. FIG. 7 is an overall view of the molding die, and FIGS. 8 to 10 are sectional views showing a door trim upper forming portion in the molding die. Further, FIGS. 11 to 15 show the respective steps of the automobile door trim manufacturing method, FIG. 11 is a preheating step of the foamed resin sheet, FIG. 12 is a step of setting the foamed resin sheet to the molding die, and FIGS. 15 is an explanatory view showing a door trim forming step, and FIG. 16 is a cross-sectional view of an essential part showing a modification of the present invention.

  First, based on FIG. 1 thru | or FIG. 6, the structure of the two-tone type vehicle door trim 10 to which the structure of the interior component for motor vehicles which concerns on this invention is applied is demonstrated. The two-tone type door trim 10 for an automobile is composed of an upper and lower divided body composed of a door trim upper 20 made of a laminated structure and a door trim lower 30 made of a single resin. And as a functional component with which the door trim 10 is mounted | worn, the inside handle escutcheon 11 and the power window switch escutcheon 12 are attached to the door trim upper 20. FIG. The door trim lower 30 is provided with a door pocket opening 13, and a pocket back cover (made of a resin molded body) 14 is attached to the rear side thereof as shown in FIG. The speaker grill 15 is provided integrally with the door trim lower 30 or separately on the front side of the door 30.

  By the way, the automotive door trim 10 according to the present invention is characterized by the structure of the door trim upper 20 formed of a laminated structure, and the weight of the product is reduced, and a good surface appearance and strong product rigidity are ensured. ing. That is, as shown in FIG. 2, the door trim upper 20 is formed into a desired curved surface shape, and has a foamed resin base material 21 having shape retention, and a resin rib integrated with the back surface side of the foamed resin base material 21. 22 and a decorating material 23 having a decorating function that is laminated and integrated on the surface side of the foamed resin base material 21. In the figure, reference numeral 16 denotes a vehicle body panel.

  The foamed resin base material 21 has a shape after heat-softening treatment of the foamed resin sheet and heat molding into a required shape, for example, cold press molding with a molding die having a desired mold surface, so as to have shape retention. Is granted. The foamed resin sheet has a structure in which a foaming agent is added to a general-purpose thermoplastic resin. The thermoplastic resin includes a polyethylene resin, a polypropylene resin, a polystyrene resin, a polyethylene terephthalate resin, a polyvinyl alcohol resin, a chloride resin. Vinyl resin, polyamide resin, polyacetal resin, polycarbonate resin, ionomer resin, acrylonitrile / butadiene / styrene (ABS) resin, etc. can be used. As the foaming agent, organic foaming agents such as azodicarbonamide and bicarbonate An inorganic foaming agent such as sodium can be used. In this embodiment, a foamed resin sheet in which sodium bicarbonate is appropriately added as a foaming agent to a polypropylene resin is used. Moreover, the expansion ratio of the foamed resin base material 21 is set to 2 to 10 times, and the thickness is set to 0.5 to 30 mm, particularly preferably 1 to 10 mm.

  Next, as shown in FIG. 3, the resin ribs 22 are set in a lattice pattern extending in the vertical and horizontal directions or in an oblique direction. And this resin rib 22 consists of a general-purpose synthetic resin molding, and as a synthetic resin which can be preferably used normally, polyethylene resin, polypropylene resin, polystyrene resin, polyethylene terephthalate resin, polyvinyl alcohol resin, vinyl chloride resin Resin, polyamide-based resin, polyacetal-based resin, polycarbonate-based resin, ionomer-based resin, acrylonitrile / butadiene / styrene (ABS) resin, and the like may be appropriately selected. In this embodiment, polypropylene is considered in consideration of environmental aspects and recycling aspects. System resin is used. The resin rib 22 is appropriately mixed with a filler such as inorganic fibers such as glass fiber and carbon fiber, and inorganic particles such as talc, clay, silica and calcium carbonate in the thermoplastic resin. May be.

  As described above, the door trim 10 shown in FIGS. 1 to 3 includes the door trim upper 20 made of a laminated structure and the door trim lower 30 which is a single synthetic resin, and has an excellent appearance design due to an accent effect on the appearance. It has sex. Furthermore, since the door trim upper 20 is composed of a foamed resin base material 21 having shape retention and a resin rib 22 laminated and integrated on the back surface of the foamed resin base material 21, it is provided on the entire surface of the product as in the past. The resin core material that has been occupied can be abolished and the lightweight foamed resin base material 21 is used. On the other hand, the resin rib 22 has a bone shape and is subjected to a load, such as a clip mounting seat, a waist flange, an armrest portion. The parts excluding the top surface have a thinned structure, so that the weight of the product can be reduced by 40% or more compared to the conventional example, and the resin material can be saved significantly. Can contribute to down.

  Furthermore, since the foamed resin base material 21 has a porous structure, the door trim upper 20 has excellent sound absorption performance and can reduce noise inside and outside the vehicle interior. Further, if desired, a decorative material may be laminated and integrated on the surface of the foamed resin base material 21. In that case, in order to improve the sound absorption performance for vehicle interior noise, the decorative material laminated and integrated on the surface of the foamed resin base material 21 has air permeability such as a woven fabric, a non-woven fabric, and a knitted fabric. Sheet material is preferred. In addition to the breathable sheets such as woven fabric, non-woven fabric, and knitted fabric, the decorative material is a synthetic resin sheet such as a vinyl chloride sheet and a TPO sheet (recyclable if a TPO sheet is used), a synthetic resin film, and a foam. A net or the like can be used. In addition, as a low-cost configuration, the decorating material may be omitted, and the surface of the foamed resin base material 21 may be subjected to painting or printing processing.

  Further, in the door trim upper 20, the foamed resin base material 21 is formed in a desired curved surface shape. In particular, it is preferable in terms of appearance to form sharp highlight lines such as corner portions of armrests. The line or the like is hereinafter referred to as a design surface convex portion 20a. And the site | part corresponding to the design surface convex part 20a has the R part corresponding | compatible resin rib 22a, as shown in FIG. As shown in FIG. 5, the rib width a <b> 1 of the resin rib 22 in the general portion is 3 mm and the rib depth b <b> 1 is 10 mm, whereas it corresponds to the design surface convex portion 20 a as shown in FIG. 6. The R portion corresponding resin rib 22a has a rib width a2 of 2.0 to 2.5 mm and a rib depth b2 of 3 to 5 mm. And by setting R part corresponding | compatible resin rib 22a in this way, when shape | molding the foamed resin base material 21 in a desired curved surface shape so that it may mention later, in the design surface convex part 20a, the foamed resin base material 21 Is characterized in that it can be prevented from falling into the groove portion of the molding die, and it is possible to prevent molding defects as much as possible.

  Next, the manufacturing method of the door trim 10 mentioned above is demonstrated below. First, based on FIG. 7 thru | or FIG. 10, the structure of the shaping die 40 is demonstrated. In FIG. 7, a molding die 40 used for molding the door trim 10 includes a molding upper mold 41 that can move up and down by a predetermined stroke, a molding lower mold 42 that is paired with the molding upper mold 41, and a molding lower mold 42. It consists of two injection machines 43a and 43b connected to each other.

  More specifically, the molding upper die 41 has a cavity portion 411 that matches 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 molding upper die 41. In addition, guide bushes 413 serving as a guide mechanism are provided at the four corners of the molding upper die 41.

  On the other hand, the molding lower die 42 is provided with a core portion 421 corresponding to the cavity portion 411 of the molding upper die 41. In addition, manifolds 422a and 422b and gates 423a and 423b are provided to supply molten resin to the mold surface of the core portion 421, and the injection machine passes through the resin passages of the manifolds 422a and 422b and gates 423a and 423b. Molten resins M1 and M2 supplied from 43a and 43b are supplied to the upper surface of the core portion 421. In order to form the resin rib 22, a groove 424 to which the molten resin M <b> 1 is supplied is formed on the upper surface of the core portion 421, while a predetermined portion is formed between the upper and lower molds 41 and 42 to form the door trim lower 30. A clearance cavity 425 is set. In addition, guide posts 426 that serve as a guide mechanism protrude from the four corners of the molded lower mold 42, and the guide posts 426 guide into the guide bush 413 when the molded upper and lower molds 41 and 42 are clamped. As a result, the pressing posture of the molding upper die 41 can be properly maintained.

  Further, as shown in FIGS. 8 to 10, the molded lower mold 42 corresponding to the door trim upper 20 is provided with a groove portion 424 corresponding to the crossed resin rib 22. In order to differentiate between the general resin rib 22 and the R portion corresponding resin rib 22a, the groove width w2 is narrower than the groove width w1 of the general groove portion 424, and is larger than the groove depth d1 of the general groove portion 424. An R portion corresponding groove portion 424a in which the groove depth d2 is set shallow is set. In addition, although not shown, the molding lower mold 42 may be provided with an air blow mechanism. As an air blow mechanism, a compressed air blower and an air blow pipe connected to the air blower communicate with the air chamber of the molding lower mold 42, and an opening / closing operation of an opening / closing valve provided in the air blow pipe causes the air blow mechanism to enter the air chamber of the molding lower mold 42. Cooling air as a refrigerant is supplied, and cooling air is blown into the cavity through an air blow hole formed in the mold surface of the molding lower mold 42. As the refrigerant, liquid nitrogen, liquid air, carbon dioxide or the like can be used in addition to the cooling air.

  Next, for reference, a method of manufacturing the door trim 10 having the above-described configuration will be briefly described with reference to FIGS. First, as shown in FIG. 11, the preheating process of the foamed resin sheet S which heat-softens the foamed resin sheet S to a predetermined temperature by the heater device 50 is employed. In this embodiment, a polypropylene foam sheet (manufactured by Sumika Plustech, trade name: Sumiceller foam PP sheet, expansion ratio = 3 times, thickness 3 mm) is used as the foam resin sheet S. Then, as shown in FIG. 12, the upper half of the cavity defined by the cavity portion 411 of the molding upper die 41 and the core portion 421 of the molding lower die 42 at the location corresponding to the door trim upper 20 is applied to the heat-softened foamed resin sheet S. Set to part. A decorative material 23 is laminated in advance on one surface of the foamed resin sheet S.

  After the foamed resin sheet S is set, as shown in FIG. 13, the raising and lowering cylinder 412 of the molding upper die 41 is operated, the molding upper die 41 is lowered by a predetermined stroke, and the molding upper and lower dies 41 and 42 are clamped. Then, the foamed resin sheet S is shaped along the cavity shape. At this time, as shown in the drawing, particularly in the portion corresponding to the design surface convex portion 20a in the door trim upper 20, although the tension is applied to the foamed resin sheet S and tends to be pushed into the groove portion 424, the design surface convex portion 20a is particularly preferred. Since the groove width w2 of the R portion corresponding groove portion 424a of the portion corresponding to the width is set narrow and the groove depth d2 is set shallow, the foamed resin sheet S in the design surface convex portion 20a falls into the R portion corresponding groove portion 424a. The design surface convex portion 20a such as a highlight line can be formed into a sharp shape. Conventionally, in the design surface convex portion 20a, it has been difficult to form a resin rib due to the drop of the foamed resin sheet S, but in the present invention, the shape of the R portion corresponding groove portion 424a is devised. By doing so, since the R portion corresponding resin rib 22a can be formed also at a position directly below the design surface convex portion 20a, the product rigidity can be enhanced.

  Next, after forming the foamed resin base material 21 into a desired curved surface shape from the foamed resin sheet S, as shown in FIGS. 14 and 15, the door trim upper 20 in the door trim upper 20 passes through the manifold 422 a and the gate 423 a from the first injection machine 43 a. In order to form the resin rib 22, the molten resin M1 is injected and filled into the groove portion 424 and the R portion corresponding groove portion 424a of the lower mold 42. Further, in order to form the door trim lower 30, the molten resin M2 is injected and filled into the cavity 425 from the second injection machine 43b through the manifold 422b and the gate 423b, and the door trim lower 30 is formed into a required shape. In addition, as this molten resin M1, M2, the resin material which fillers, such as a talc, are mixed in an appropriate ratio with Sumitomo Nobrene BUE81E6 (the polypropylene made from Sumitomo Chemical, melt index = 80 g / 10min) is used. . Therefore, the molten resin M1 is injected and filled into the groove portion 424 and the R portion corresponding groove portion 424a from the first injection machine 43a, while the molten resin M2 is injected and filled into the cavity 425 from the second injection machine 43b. The resin rib 22 in the upper 20 is formed into a required shape, and the door trim lower 30 is integrally formed integrally therewith.

  FIG. 16 shows a modification of the present invention, and the step A in the door trim upper 20 corresponds to the design surface convex portion 20a. Therefore, also in the resin rib 22, the R portion corresponding resin rib 22a is formed at the corresponding portion of the stepped portion A, and the rib width of the R portion corresponding resin rib 22a is narrow and the rib depth is set shallow. . Therefore, when the foamed resin base material 21 is molded, the foamed resin sheet S does not fall into the groove portion 424, and the stepped portion A can be accurately shaped.

  Thus, especially the door trim 10 for motor vehicles based on this invention is comprised as the structure of the door trim upper 20 from the foamed resin base material 21 and the resin rib 22 integrated with a back surface, and promotes weight reduction. In particular, with respect to the design surface convex portion 20a such as a highlight line along the corner edge of the armrest of the door trim upper 20, by setting the R portion corresponding groove portion 424a to the shape of the groove portion 424 provided in the molding lower mold 42, The design surface convex portion 20a can be accurately shaped, and the rigidity can be enhanced by setting the R portion resin rib 22a on the design surface convex portion 20a, thereby improving the appearance performance and product rigidity. Has the advantage of being able to.

  In the embodiment described above, the structure of the present invention is applied to the door trim upper 20 in the two-tone type automobile door trim 10, but the interior door trim or the interior parts other than the door trim, such as the rear parcel shelf, the floor trim, and the trunk trim. The structure of the present invention can be applied to interior trims such as luggage trim, roof trim, rear side trim, and the like.

It is a front view which shows the door trim which is one Example of the interior component for motor vehicles based on this invention. It is the II-II sectional view taken on the line in FIG. It is a front view which shows the resin rib and door trim lower of the door trim upper in the door trim shown in FIG. It is sectional drawing which shows the principal part structure of the door trim upper in the door trim shown in FIG. FIG. 5 is a sectional view taken along line V-V in FIG. 4. FIG. 6 is a sectional view taken along line VI-VI in FIG. 4. It is explanatory drawing which shows the whole structure of the molding die used when shape | molding the door trim shown in FIG. It is principal part sectional drawing which shows the site | part which shape | molds the design surface convex part of the door trim upper in the molding die shown in FIG. It is the IX-IX sectional view taken on the line in FIG. FIG. 9 is a sectional view taken along line X-X in FIG. 8. It is explanatory drawing which shows the preheating process of the foamed resin sheet in the manufacturing method of the door trim shown in FIG. It is explanatory drawing which shows the in-mold setting process of the foamed resin sheet in the manufacturing method of the door trim shown in FIG. It is explanatory drawing which shows the formation process of the foamed resin base material in the manufacturing method of the door trim shown in FIG. It is explanatory drawing which shows the formation process of the resin rib of the door trim upper in the manufacturing method of the door trim shown in FIG. 1, and the formation process of a door trim lower. It is explanatory drawing which shows the formation process of the door trim upper in the manufacturing method of the door trim shown in FIG. It is sectional drawing which shows the modification of the door trim upper in the door trim shown in FIG. It is a front view which shows the conventional door trim. FIG. 18 is a cross-sectional view taken along line XVIII-XVIII in FIG. It is explanatory drawing which shows the structure of the shaping die used when shape | molding the conventional door trim.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Two-tone type automobile door trim 20 Door trim upper 20a Design surface convex part 21 Foam resin base material 22 Resin rib 22a Resin rib corresponding to R part 23 Decorating material 30 Door trim lower 40 Molding die 41 Molding upper mold 42 Molding lower mold 424 Groove part 424a R part corresponding groove part 43a, 43b Injection machine M1, M2 Molten resin S Foamed resin sheet a1, a2 Rib width b1, b2 Rib depth w1, w2 Groove width d1, d2 Groove depth A Step part

Claims (2)

A foamed resin base material (21) that is molded into a desired curved surface shape and is lightweight and has shape retention, and a resin rib (22) that is integrated with the back surface of the foamed resin base material (21), In the foamed resin base material (21), the heat-softened foamed resin sheet (S) is drawn in the molded upper and lower molds (41, 42) and in the groove (424) of the molded lower mold (42). A laminated structure (20) in which resin ribs (22) are integrated with the back surface of the foamed resin base material (21) is used in whole or in part by injecting and filling the molten resin (M1). In automotive interior parts (10)
An R portion corresponding resin rib (22a) is formed at a position corresponding to the design surface convex portion (20a) of the laminated structure (20), and a rib width (a1) and a rib depth of a general resin rib (22) ( Compared to b1), the rib width (a2) of the R portion corresponding resin rib (22a) is set to be narrow and the rib depth (b2) is set to be shallow, so that the groove portion (424) can be formed when the foamed resin sheet (S) is drawn. ) Automotive interior parts characterized by avoiding falling into the interior. The rib width (a2) of the R portion corresponding resin rib (22a) provided at the location corresponding to the design surface convex portion (20a) of the laminated structure (20) is 2.0 to 2.5 mm, and the rib depth (b2). Is set within a range of 3 to 5 mm.

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