JP2007069875A - Interior trimming part for automobile, and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce weight and costs, improve the appearance of an outer peripheral terminal, and simplify a terminal processing operation in connection with interior trimming parts for an automobile and a manufacturing method thereof. <P>SOLUTION: A door trim upper (laminate structure) 20 of a two-tone type door trim 10 comprises a light foamed resin base material 21 having a form retention property, a resin rib 22 integrated with its inner face, and a decorating material 23 laminated on the surface of the foamed resin base material 21. Accordingly, the light foamed resin base material 21 is used and a projection area at the resin rib 22 is reduced, so as to realize a light weight and reduce costs. Also, a smashing stepped face block 44 is arranged on the outer periphery of a cavity of a molding die 40, and a thin winding piece 26 is formed at the same time of molding the foamed resin base material 21. After molding, the strong winding piece 26 is subject to a single bending operation, so as to complete the terminal processing. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to interior parts for automobiles such as door trims, rear parcel shelves, floor trims, trunk trims, luggage trims, roof trims, rear side trims, and methods for manufacturing the same. The present invention relates to an automobile interior part that can be easily and inexpensively processed along a terminal, and a method of manufacturing the same.

  For example, the configuration of automobile interior parts will be described with reference to FIGS. 13 and 14 exemplifying door trims. The door trim 1 has a shape retaining property and a mounting rigidity to a vehicle body panel, and is formed by laminating and integrating a skin 3 excellent in surface appearance on the surface of a resin core material 2 that extends over almost the entire product surface. Yes. The resin core material 2 is made of a polypropylene resin mixed with talc, and the skin 3 does not have shape retention itself, and the back surface of the synthetic resin sheet such as a vinyl chloride sheet is made of polyethylene foam or the like. A laminated sheet material in which a cushion material is laminated is used, and recently, an elastomer sheet such as a thermoplastic olefin (hereinafter referred to as TPO) sheet tends to be frequently used in consideration of environmental aspects and recycling aspects.

  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 molding upper 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 of 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, either the skin 3 is set in the mold, and then either immediately before or after the molding upper and lower molds 5 and 6 are clamped The molten resin M is injected and filled from the injection machine 7 through the manifold 6b and the gate 6c into the product cavity between the molds at the timing, thereby forming the resin core material 2 into a required curved shape and the resin core material 2 The skin 3 is integrally formed on the surface (for example, see Patent Document 1). In FIG. 15, for convenience of explanation, the molten resin M is supplied to the mold surface of the core portion 6 a in an open state, but actually, the molten resin M is injected into the cavity after the mold upper and lower molds 5 and 6 are clamped. It may be filled.

  Further, regarding the processing of the outer peripheral terminal of the product of the door trim 1, as shown in FIG. 16, after the outer skin 3 is simultaneously press-molded on the surface of the core material 2, the piercing is performed in a separate process after the mold blade in the mold or molding. Cut processing is performed. In addition, as shown in FIG. 17, after the core material 2 is press-molded, the skin 3 is integrated by vacuum pressing, press-bonding, etc. in a separate process, and then the terminal 3 a of the skin 3 is wound around the back surface side of the core material 2. Processing is also conventionally performed.

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.

  Further, at the outer periphery of the door trim 1, as shown in FIG. 16, when the outer skin is subjected to simultaneous press molding, it is difficult to treat the outer periphery, and the mouth layer of the outer skin 3 or the foam layer in the outer skin 3 of the laminated sheet material specification. As shown in FIG. 17, the method of enveloping the epidermis 3 in a separate process increases the number of steps and increases the cost. Inevitable.

  The present invention has been made in view of such circumstances, and can provide an automotive interior part that can promote weight reduction, can achieve high rigidity, and can reduce costs, and in particular, can enhance the appearance of a product outer peripheral terminal portion. Another object of the present invention is to provide an automobile interior part with improved appearance performance that can easily perform terminal processing work and a method for manufacturing the same.

  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. High rigidity is required at places where rigidity is required, that is, at the peripheral part of the product, the panel, the mating part with the mating part, or where a certain clearance is secured, or where the part is attached and where the load is applied By arranging the resin ribs, the conventional resin core material with a large projected area is abolished and the product weight is reduced, and the outer peripheral terminal treatment of the product is beautiful by devising the entrainment piece shape. It has been found that terminal processing can be achieved, and the present invention has been completed.

  That is, the present invention relates to a laminated structure comprising a foamed resin base material that is molded into a required shape and is lightweight and has shape retention, and resin ribs having a predetermined pattern shape integrated with the back surface of the foamed resin base material. In the interior part for automobiles that adopts the whole or a part, the laminated structure is put into a molding die after the foamed resin sheet that is the material of the foamed resin base material is heat-softened, By clamping the molding die, the foamed resin base material is molded into the required shape, and the folding piece for winding is integrally formed in a hook shape along at least a part of the peripheral edge of the laminated structure. The terminal processing structure which bends and fixes the bending piece to the peripheral back surface side of a foamed resin base material is employ | adopted.

  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. And if the foamed resin base material that is lightweight and has shape retention properties is close to a flat shape, the heat softening step is omitted and it is molded into a desired shape by a mold, but it is applied to a three-dimensional product. In this case, after the foamed resin sheet is heat-softened, the foamed resin sheet is molded into a required curved shape in a molding die, and the shape is maintained. Here, “shape retention” refers to having rigidity enough to retain the shape when the mold is removed after molding, even without a reinforcing material such as a rib. Also, if the product shape includes a high expansion ratio part, after the foamed resin sheet is heat-softened, a vacuum suction mechanism is provided in the molding die and the foamed resin sheet is vacuumed along the inner surface of the molding die. A suction force may be applied.

  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 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.

  Further, if desired, a decorating material may be integrated with the surface of the foamed resin base material in order to enhance the appearance design. As the decorating material, thermoplastic resin sheets such as TPO, thermoplastic urethane (TPU), PVC, or fabric sheets such as woven fabric, non-woven fabric, knitted fabric can be used. These thermoplastic resin sheets, woven fabric, non-woven fabric Further, a foam sheet such as polyurethane foam, polyethylene foam, and polypropylene foam can be laminated and integrated as a cushion layer on the back surface of a fabric sheet such as a knitted fabric. In addition, if TPO sheet or polyethylene foam is used as the material of the decorating material and olefin resin is used as the material of the foamed resin base material or resin rib, all materials can be unified into the olefin resin and recycled. Above preferred.

  And according to the interior part for automobiles according to the present invention, the laminated structure employed in a part or the whole has a resin rib that reinforces rigidity on the back side of a lightweight and shape-retaining foamed resin base material. Because it is an integrated structure, the conventional resin core material with a very large projected area can be eliminated, so the product can be reduced in weight and the resin material can be saved, reducing the material cost. Can also be achieved.

  Furthermore, at the end portion along the entire length or a part of the peripheral edge of the laminated structure, hook-shaped folding pieces for winding are formed integrally with the foamed resin base material. And after molding, after removing the laminated structure from the molding die, the folding piece for winding should be bent and fixed to the peripheral back side of the foamed resin base material based on the thin hinge portion. Since the cut end is not exposed to the outside, the appearance looks good. Further, the rigidity of the folding part for winding can enhance the rigidity of the terminal portion, and the peripheral line does not meander, so that the appearance looks better.

  In addition, the porous sound-absorbing function of the foamed resin base material provides interior parts with excellent sound-absorbing performance. When polyolefin resin is used as the material for the foamed resin base material and resin ribs, Since it is unified, the separation process can be abolished and the recycling work can be simplified. Furthermore, the rib thickness of the resin rib can be varied as appropriate, for example, by setting the rib thickness to be thicker at sites where a large external force is applied to the product, and by reducing the rib thickness at sites where external force is relatively difficult to apply. Can do. Therefore, it is sufficient to use the minimum necessary amount of resin material, which can contribute to weight reduction and cost reduction of the product. Moreover, the clip seat or the attachment seat for attaching various escutcheon parts can also be integrally formed in the resin rib.

  Next, the present invention provides a laminated structure comprising a foamed resin base material that is molded into a required shape and is lightweight and has shape retention, and a resin rib having a predetermined pattern shape that is integrated on the back surface of the foamed resin base material. In the manufacturing method of interior parts for automobiles, wherein the laminated structure is manufactured by heat-softening a foamed resin sheet, which is a material of the foamed resin base material, in a mold Then, the molds are clamped together to form the foamed resin base material into the required shape, and wound between the crushing stepped block provided along the peripheral edge of the product and the molding upper mold. Molded folding piece is molded into a hook shape along at least a part of the periphery of the laminated structure, and molten resin is inserted into the groove of the lower mold either before or after mold clamping. By injection filling the resin rib A laminated structure is formed integrally with the back side of the foam resin base material, and then the mold is opened after the mold is opened, and the laminated structure is removed from the mold, and the folding fold is integrally formed on the periphery of the laminated structure. Folding the bent piece to the back side of the peripheral edge of the foamed resin base material based on the thin-walled hinge portion, and performing a terminal processing step of attaching the peripheral edge portion of the foamed resin base material with the folding piece for winding And

  Here, the molding die used in the method of the present invention includes a movable side die, a fixed side die, and an injection machine. For example, it is composed of a molding upper mold that can move up and down by a predetermined stroke, a molding lower mold positioned below the molding upper mold, and an injection machine connected to the molding lower mold. When the molding upper and lower molds are used, the molten resin supplied from the injection machine passes through the resin passages such as the manifold and gate provided in the molding lower mold, and more specifically the mold surface of the molding lower mold. The upper mold is lowered to the bottom dead center and the upper and lower molds are clamped, and then the molten resin is provided on the mold surface of the lower mold with a predetermined injection pressure. The groove portion may be injected and filled, but may be performed before mold clamping as the injection filling timing of the molten resin. Further, a crushing stepped block is supported by a cylinder so that it can be moved up and down along the vertical direction by a cylinder at the peripheral edge of the molding lower mold, and this crushing stepped block is a foamed resin between the molding upper mold and the mold. The base material can be formed into a required shape. Specifically, a hook-shaped folding piece for winding is formed.

  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. Therefore, the injection pressure can be set lower than the conventional one, so that the load on the molding die can be reduced. Therefore, the resin material can be saved, and the cooling time can be shortened as compared with the conventional resin core material, so that the product molding cycle can be shortened.

  Further, as a terminal treatment step along the peripheral edge of the laminated structure, the winding folded piece is integrally formed in a hook shape at the same time as the molding of the foamed resin base material. Is removed, and the winding operation is completed simply by folding the hook-shaped folding piece toward the back side of the foamed resin base material by about 180 ° based on the thin-walled hinge part. Compared to the cumbersome operation of winding the winding scissors along two directions in two operations, as in the prior art, the operation is completed in one operation.

  As described above, the automobile interior part according to the present invention is required to have rigidity such as a lightweight and shape-retaining foamed resin base material, a back surface of the foamed resin base material, and an outer peripheral edge of the product. Because it is composed of resin ribs that are laminated and integrated with the surface of the foamed resin base material, and a decorative material that is laminated on the surface of the foamed resin base material, the conventional heavy resin core material can be eliminated. And since it is a porous material, it has the effect that the interior component for motor vehicles excellent in the sound absorption performance can be provided.

  Furthermore, if the process of molding the resin foam on the back side of the foamed resin base material at the same time as molding the foamed resin base material into the required shape along the cavity shape of the molding die, the resin rib that is a resin molded body Compared to conventional resin core materials, the projected area is less, the load on the mold is less, the cooling time can be shortened, and the yield can be increased. This has the effect of reducing the cost.

  In addition, according to the automotive interior part and the method for manufacturing the same according to the present invention, when the foamed resin base material is molded, the hook-shaped folding piece for winding is integrally molded along at least a part of the periphery of the laminated structure. After the mold is removed from the molding die, the folding piece for winding is bent and fixed to the back side of the foamed resin base material, so that the rigidity of the peripheral edge of the laminated structure is enhanced. In addition, there is no appearance defect such as meandering and undulation, and it is possible to enhance the appearance of the peripheral portion, and the terminal processing step is conventionally hooked in two directions and two operations. Since the terminal processing is completed simply by bending the folding piece, the terminal processing work can be simplified.

  BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a preferred embodiment of an automobile interior part and a method for manufacturing the same according to the present invention will be described by illustrating an automobile door trim and a method for manufacturing the same. 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.

  1 to 12 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 cross-sectional view showing the configuration of the automobile door trim, and FIG. 4 is a front view showing a resin rib and a door trim lower of the door trim upper in FIG. 4, FIG. 4 is a cross-sectional view showing a configuration of a terminal portion of the door trim upper in the automobile door trim, and FIGS. 5 and 6 are used in the manufacturing method of the door trim for the automobile. FIG. 5 is an overall view of the molding die, and FIG. 6 is a cross-sectional view showing a portion corresponding to the edge portion of the door trim upper in the molding die. 7 to 12 show the respective steps in the manufacturing method of the door trim for the automobile. FIG. 7 is a preheating step for the foamed resin sheet, FIG. 8 is a step for setting the foamed resin sheet in the mold, and FIG. FIG. 10 is an explanatory view showing a forming process of a base material, FIG. 10 is a forming process of a folding piece for winding, FIG. 11 is a forming process of a resin rib, and FIG.

  First, an embodiment of the present invention will be described with reference to FIGS. 1 and 2, a two-tone type automobile door trim 10 is composed of an upper and lower divided part of a door trim upper 20 made of a laminated structure and a door trim lower 30 made of a single resin product. As functional components to be mounted on the door trim 10, an inside handle escutcheon 11 and a power window switch escutcheon 12 are attached to the door trim upper 20. The door trim lower 30 is provided with a door pocket opening 13, and on the back side thereof, as shown in FIG. 2, a pocket back cover (made of a resin molded body) 14 is attached. On the side, the speaker grill 15 is formed integrally with or separately from the door trim lower 30.

  By the way, the door trim 10 for automobiles according to the present invention is applied to the structure of the door trim upper 20 which is a laminated structure to reduce the weight of the product, improve the appearance of the outer peripheral terminal portion, and form the molding process, terminal It is characterized by a simplified processing process. That is, as shown in FIG. 2, the door trim upper 20 is molded into a desired curved surface shape and has a foamed resin base material 21 having shape retention, and a resin laminated and integrated on the back surface side of the foamed resin base material 21. The rib 22 and the decorating material 23 having a decorating function laminated and integrated on the surface side of the foamed resin base material 21 are roughly configured. In the figure, reference numeral 16 denotes a vehicle body panel. In addition, the foamed resin base material 21 is heat-softened to heat the foamed resin sheet so as to have shape retention, and then thermoformed into a required shape, for example, cold press-molded with a molding die having a desired mold surface. Further, the portion with a higher development rate may be shaped by vacuum forming.

  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. The expansion ratio of the foamed resin base material 21 is set to 2 to 10 times, and the thickness is set to a range of 0.5 to 30 mm, particularly 1 to 10 mm.

  Next, the resin ribs 22 are disposed on the back surface side of the foamed resin base material 21 and, in particular, are set in a predetermined pattern extending in an intersecting manner as shown in FIG. In addition, as for this pattern, arbitrary patterns may be selected as long as it is intersecting, such as a vertical and horizontal direction, an oblique direction, or a combination thereof. The resin rib 22 is made of a general-purpose synthetic resin molded body, and as a synthetic resin that can be preferably used normally, a polyethylene resin, a polypropylene resin, a polystyrene resin, a polyethylene terephthalate resin, a polyvinyl alcohol resin, a vinyl chloride resin, A polyamide resin, a polyacetal resin, a polycarbonate resin, an ionomer resin, an acrylonitrile / butadiene / styrene (ABS) resin, or the like may be selected as appropriate. In this embodiment, a polypropylene resin is used in consideration of environmental and recycling aspects. 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 formed of a laminated structure and the door trim lower 30 of a single resin, and has an excellent appearance design due to an accent effect on the appearance. I have. Further, the door trim upper 20 includes a foamed resin base material 21 having shape retention, a resin rib 22 laminated and integrated on the back surface of the foamed resin base material 21, and a decorating material 23 having a decorating property. Therefore, the resin core material that has been occupied over the entire circumference of the product as in the past can be abolished, and the resin rib 22 is skeleton-like in relation to the use of the lightweight foamed resin base material 21, and a load is applied. Parts, for example, parts excluding the clip seat, the waist upper surface, the arm rest upper surface, etc. have a thinning structure, so that the weight of the product can be reduced by 40% or more compared to the conventional example. In addition, the resin material can be saved significantly, which can contribute to cost reduction.

  Furthermore, since the foamed resin base material 21 has a porous structure, the door trim upper 20 is excellent in sound absorption performance and can reduce noise in the vehicle interior. In order to maintain the sound absorption of the foamed resin base material 21, the decorative material 23 laminated in advance on the surface of the foamed resin base material 21 or laminated and integrated at the time of molding is a woven fabric, non-woven fabric, knitted fabric, or the like. A sheet material having air permeability such as cloth is preferable. The decorative material 23 may be a synthetic resin sheet such as a vinyl chloride sheet or a TPO sheet, a synthetic resin film, a foam, a net, or a fabric sheet, a synthetic sheet, in addition to a breathable sheet such as a woven fabric, a nonwoven fabric, or a knitted fabric. A laminated sheet material in which a cushion layer such as polyethylene foam or polyurethane foam is lined on the back surface of the resin sheet can also be used. In addition, when a TPO sheet is used, it can be unified with an olefin resin material, which is advantageous in terms of recycling.

  And the outer periphery terminal structure of the door trim upper 20 in the door trim 10 is demonstrated based on FIG. That is, in the door trim upper 20, as described above, the resin ribs 22 having a predetermined pattern shape for reinforcing rigidity are integrated on the back surface of the lightweight foamed resin base material 21 having shape retention, and the foamed resin base material 21. A decorative material 23 having a decorative property is laminated and integrated on the surface. Further, a flange 24 for imparting a three-dimensional effect to the product is formed downward along the outer peripheral part of the door trim upper 20, and the cut end of the terminal part is not exposed and is beautiful. Terminal processing is applied. That is, at the lower end of the flange 24, a folding piece 26 for winding is formed in a hook shape simultaneously with the molding of the foamed resin base material 21 based on the thin hinge portion 25. The folding piece 26 for winding is formed on the foamed resin. By performing a bending operation on the peripheral back surface side of the base material 21, the terminal processing is easily completed. And since the folding piece 26 for winding shape | molded in the hook shape is compressed in thin flat shape, since it is rich in rigidity, while being able to hold | maintain the rigidity of the peripheral part of the door trim upper 20 more firmly, The thin hinge portion 25 does not meander, and a sharp and beautiful appearance can be obtained.

  Next, a method for manufacturing the door trim 10 will be described, particularly focusing on the formation of the folding piece 26 for winding and the terminal processing step. Before that, the door trim 10 is formed based on FIGS. 5 and 6. The structure of the molding die 40 to be used will be described. In FIG. 5, 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 the molten resin to the mold surface of the core portion 421. The molten resins M1 and M2 supplied from 43a and 43b are supplied into a groove 424 formed on the upper surface of the core 421 and into a cavity 425 for forming the door trim lower 30. 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.

  FIG. 6 shows a portion corresponding to the outer peripheral end portion of the door trim upper 20 in the molding die 40. In the molding die 40, the outer peripheral portion of the core portion 421 of the lower molding die 42, that is, along the outer periphery of the product cavity. A crushing stepped block 44 is disposed on the entire length of the periphery, or at least a part thereof (actually where the winding folding piece 26 is set). It is supported so that the stroke can move up and down. On the other hand, the forming upper die 41 is also connected to the crushing stepped block 44 described above, and the stepped portion 414 is also set on the forming upper die 41 in order to form the winding folded piece 26 in a hook shape. The dimensions of the step 414 and the dimensions of the step 414 of the crushing stepped block 44 are appropriately set according to the thickness of the door trim upper 20.

  Next, using the molding die 40, each step of the method for manufacturing the door trim 10 will be described in detail. The steps of the door trim 10 will be described with reference to FIGS. 7 to 12. First, as shown in FIG. 7, the foamed resin sheet S is heated and softened to a high temperature state of 160 to 220 ° C. by the heater device 50. . As the foamed resin sheet S, a polypropylene foam sheet (manufactured by Sumika Plustech, trade name: Sumiceller foam PP sheet, expansion ratio = 3 times, thickness 3 mm) is used. In addition, the decorating material 23 is laminated on one surface of the foamed resin sheet S in advance.

  When the heating step of the foamed resin sheet is completed, as shown in FIG. 8, 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 are applied to the foamed resin sheet S subjected to heat softening. Set in the upper half of the cavity defined by Thereafter, as shown in FIG. 9, after setting the foamed resin sheet S (with the decorative material 23 laminated) in the molding die 40, the lifting cylinder 412 of the molding upper die 41 is driven to The mold 41 is lowered by a predetermined stroke, and as shown in the figure, the molding upper and lower molds 41 and 42 are clamped to mold the foamed resin sheet S into a desired curved surface shape.

  Then, in the same process as the molding process of the foamed resin base material 21, the hook-shaped folding folding piece 26 is integrally molded integrally with the foamed resin base material 21 through the thin hinge portion 25. As shown in FIG. 10, the crushing stepped block 44 provided on the outer periphery of the core portion 421 of the lower molding die 42 is raised by driving the cylinder 45, and between the stepped portion 414 of the molding upper die 41. A folding piece 26 for winding is formed into a hook shape. The dimensions of the folding piece 26 for winding are regulated by the dimensions of the upper surface 441 and the side surface 442 constituting the step portion of the crushing stepped block 44. And the thickness of this folding piece 26 for winding is good to set to 0.6-1.0 mm. Thereafter, as shown in FIG. 11, in order to form the resin rib 22 in the door trim upper 20 from the first injector 43a through the manifold 422a and the gate 423a, the molten resin M1 is injected and filled into the groove portion 424 of the core portion 421. The At the same time, in order to mold 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 molded into a required shape.

  Therefore, the resin ribs 22 in the door trim upper 20 are formed into a required shape by injecting and filling the molten resins M1 and M2 into the groove 424 and the cavity 425 from the first injection machine 43a and the second injection machine 43b, respectively. At the same time, the door trim lower 30 is formed integrally therewith. As the molten resins M1 and M2, Sumitomo Nobrene BUE81E6 (polypropylene manufactured by Sumitomo Chemical Co., Ltd., melt index = 65 g / 10 min) is used. If desired, talc may be mixed in an appropriate proportion. good. The injection timing of the molten resins M1 and M2 may be set before the mold upper and lower molds 41 and 42 are clamped.

  When the molding of the door trim 10 including the door trim upper 20 and the door trim lower 30 is completed, the molding die 41 is lifted to remove the door trim 10 from the molding die 40, and FIGS. 12 (a) and 12 (b). As shown in FIG. 5, the terminal processing of the door trim upper 20 may be performed. That is, as shown in FIG. 12 (a), the terminal processing step of the door trim upper 20 is first performed by the winding bent piece 26 formed in a hook shape integrated with the outside of the foamed resin base material 21. After the outer end material a is removed by cutting, as shown in FIG. 12 (b), the winding folding piece 26 formed in a hook shape is bent at an angle of approximately 180 °. If the adhesive is previously applied to the side of the foamed resin base material 21 on the joining side, the folding piece 26 for winding can be firmly adhered and fixed to the peripheral back surface side of the foamed resin base material 21. In addition to adhesive fixing, after bending the winding folding piece 26, ultrasonic welding vibration may be applied to weld and fix the winding folding piece 26.

  Therefore, as the terminal processing step, the folding piece 26 for winding is urged to the final winding shape and formed in advance so that the folding piece 26 can be bent at an angle of 180 °. Since one operation is sufficient, the terminal processing operation can be greatly simplified and the thickness of the flange 24 can be reduced compared to the conventional winding operation that requires two operations for each of the two winding directions. Since a constant thickness can always be ensured without variation, it is advantageous in terms of molding accuracy and alignment accuracy with the counterpart part.

  In the embodiment described above, the present invention is applied to the door trim upper 20 in the two-tone type automobile door trim 10. However, the present invention includes a rear parcel shelf as an integrated door trim 10 and other interior parts. It can be applied to all interior parts such as floor trim, trunk trim, luggage trim, roof trim, rear side trim.

It is a front view which shows the door trim for motor vehicles which applied one Example of 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 which abbreviate | omitted the foamed resin base material in the door trim for motor vehicles shown in FIG. It is the IV-IV sectional view taken on the line in FIG. FIG. 2 is an overall view of a molding die used in the method for manufacturing the automobile door trim shown in FIG. 1. It is sectional drawing which shows the location corresponded to the edge part of the door trim upper in the shaping die shown in FIG. It is explanatory drawing which shows the preheating process of the foamed resin sheet in the manufacturing method of the door trim for motor vehicles shown in FIG. It is explanatory drawing which shows the setting process to the shaping die of the foamed resin sheet in the manufacturing method of the door trim for motor vehicles shown in FIG. It is explanatory drawing which shows the formation process of the foamed resin base material and resin rib in the manufacturing method of the door trim for motor vehicles shown in FIG. It is explanatory drawing which shows the formation process of the folding piece for winding in the manufacturing method of the door trim for motor vehicles shown in FIG. It is explanatory drawing which shows the formation process of the resin rib in the manufacturing method of the door trim for motor vehicles shown in FIG. 1, and a door trim lower. It is explanatory drawing which shows the terminal process process of the door trim upper in the manufacturing method of the door trim for motor vehicles shown in FIG. It is a front view which shows the conventional door trim for motor vehicles. FIG. 14 is a sectional view taken along line XIV-XIV in FIG. 13. It is a schematic diagram which shows the shaping die used when shape | molding the conventional door trim. It is explanatory drawing which shows the prior art example of the terminal part in the door trim by press molding. It is explanatory drawing which shows the prior art example of the terminal part in a skin-wrapping type door trim.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Two-tone type automobile door trim 20 Door trim upper 21 Foamed resin base material 22 Resin rib 23 Decorating material 24 Flange 25 Thin-walled hinge part 26 Folding piece 30 Door trim lower 40 Molding die 41 Molding upper mold 42 Molding lower mold 43 (43a, 43b) Injection machine 44 Step block for crushing 45 Drive cylinder 50 Heater device S Foamed resin sheet M1, M2 Molten resin

Claims (2)

A foamed resin base material (21) which is molded into a required shape and is lightweight and has shape retention, and a resin rib (22) having a predetermined pattern shape integrated with the back surface of the foamed resin base material (21). In an automotive interior part (10) formed by adopting the laminated structure (20) in whole or in part,
After the foamed resin sheet (S), which is the material of the foamed resin base material (21), is heat-softened, the laminated structure (20) is put into the molding die (40), and the molding die (40 ) To mold the foamed resin base material (21) into a required shape, and the winding folded piece (26) has a hook shape along at least a part of the periphery of the laminated structure (20). An automobile interior part characterized by adopting a terminal processing structure that is integrally molded and that bends and fixes the winding folding piece (26) to the peripheral back surface side of the foamed resin base material (21). A foamed resin base material (21) which is molded into a required shape and is lightweight and has shape retention, and a resin rib (22) having a predetermined pattern shape integrated with the back surface of the foamed resin base material (21). In the manufacturing method of the automotive interior part (10) formed by employing the laminated structure (20) in whole or in part,
The laminated structure (20) is manufactured by heat-softening the foamed resin sheet (S), which is the material of the foamed resin base material (21), and placing the mold into the mold (40), and then molding the mold. (40) The molds are clamped together, the foamed resin base material (21) is molded into a required shape, a crushing stepped block (44) provided along the product peripheral edge, and a molding upper mold (41) The folding piece (26) for winding is formed into a hook shape along at least a part of the peripheral edge of the laminated structure (20), and either before the mold clamping of the molding die (40) or after the mold clamping. The molten resin (M1) is injected and filled into the groove (424) of the molded lower mold (42) at this timing, so that the resin rib (22) is integrated and laminated on the back side of the foamed resin base material (21). After the structure (20) is molded and then the mold (40) is opened, the laminated structure is formed. The body (20) is demolded, and the winding bent piece (26) formed integrally with the periphery of the laminated structure (20) is used as the periphery of the foamed resin base material (21) based on the thin hinge portion (25). A method of manufacturing an interior part for an automobile, which is subjected to a terminal operation process for folding the foam resin base material (21) with a folding piece (26) for folding on the back side. .

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