JP4737530B2 - Manufacturing method for interior parts for automobiles - Google Patents

Description

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

  For example, the configuration of automobile interior parts will be described with reference to FIGS. 16 and 17 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. When the upper and lower molds 5 and 6 are clamped, a cavity portion 5a is formed in the molded upper mold 5 and a core section 6a is provided in the molded lower mold 6 in order to shape the product shape of the door trim 1. Yes. Further, 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 for molten resin from the injection machine 7. . Further, in order to maintain an appropriate posture, the upper molding die 5 that moves up and down is provided with guide posts 6d at the four corners of the lower molding die 6, and the molding upper die 5 has guides corresponding 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. 18, for convenience of explanation, the molten resin M is supplied to the mold surface of the core portion 6 a in an open state. Actually, however, 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 door trim 1 product, as shown in FIG. 19, the outer skin 3 is simultaneously press-molded on the surface of the core material 2 and then cut or molded by the mold blade in the mold. Thereafter, piercing cut processing is performed in a separate process. Further, as shown in FIG. 20, 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.

  Furthermore, in the outer periphery of the door trim 1, as shown in FIG. 19, when the outer skin simultaneous press molding is performed, the outer peripheral terminal processing is difficult, and in the case of the skin 3 of the skin 3 or the skin 3 of the laminated sheet material specification, The form layer is exposed to the outside, such as being exposed to the outside, and has the disadvantages of deteriorating the appearance performance. As shown in FIG. 20, the method of winding the skin 3 in a separate process requires a lot of man-hours and costs. Up is 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. In addition, an object is to provide a method for manufacturing interior parts for automobiles that can easily perform terminal processing work.

  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, i.e. it can be closely contacted with the peripheral part of the product, the panel, the mating part with the mating part, or a part where a certain clearance is secured, or where a part is attached and where a load is applied By arranging the resin ribs, the product is lighter than conventional resin cores with a large projected area. It was found that it could be done quickly, and the present invention was completed.

  That is, the method for manufacturing an automobile interior part according to the present invention includes a foamed resin base material that is molded into a required shape and is lightweight and has shape retention, and 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, in which the laminated structure composed of the resin rib and the decorative material affixed to the surface of the foamed resin base material is employed in whole or in part, the laminated structure is When opening the mold upper and lower molds, decorating material and heat softened foam resin sheet are set in the mold upper and lower molds, and the mold upper and lower molds are clamped to mold the foam resin sheet into the mold Press molding into a desired curved shape along the cavity shape of the mold, and shear action between the shear block made of resin material or light metal material arranged on the outer periphery of the cavity of the molding lower mold and the inner wall surface of the molding upper mold More, by trimming the foamed resin sheet with a predetermined dimension, and then injection-filling the molten resin into the groove portion of the molded lower mold at any timing immediately before or after mold clamping of the molded upper and lower molds, A resin rib is integrated on the back side of the foamed resin base material to form a laminated structure, and after the mold upper and lower molds are opened, the laminated structure is removed, and then the foamed resin is formed. It is manufactured by the process which consists of a winding process process of the decorating material which winds and processes the winding of a decorating material on the back surface side of a base material, It is characterized by the above-mentioned.

  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 heat-softening the foamed resin sheet and molded into a required shape 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.

  And in order to improve an external appearance design property, the decorating material is integrated with the surface of the foamed resin base material. As the decorating material, thermoplastic resin sheets such as TPO, thermoplastic urethane (TPU), and polyvinyl chloride (PVC), or fabric sheets such as woven fabric, non-woven fabric, and knitted fabric can be used. Further, a foam sheet such as polyurethane foam, polyethylene foam, polypropylene foam or the like can be laminated and integrated as a cushion layer on the back surface of the fabric sheet such as thermoplastic resin sheet, woven fabric, nonwoven fabric, knitted fabric or the like. 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.

  The interior parts for automobiles manufactured by the method of the present invention are resin ribs in which a decorative material having a decorative property is laminated on the front surface side of a foamed resin base material having shape retention, and the rigidity is enhanced on the back surface side. Can be abolished, so that the conventional resin core material can be eliminated. Therefore, since the conventional resin core material with a very large projected area can be eliminated, the weight of the product can be reduced, and the resin material can be saved, so that the material cost can be reduced at the same time.

  Furthermore, in the terminal portion along the outer periphery of the product of the laminated structure, the end of the foamed resin sheet is used as the foamed resin base material by the shearing action between the shear block arranged in the molded lower mold and the inner wall surface of the molded upper mold. Can be cut and removed at the same time as molding. Therefore, since the decorating material may be wound around the back side of the foamed resin base material based on the cut line of the foamed resin base material, the cut end is not exposed to the outside, and the appearance is good. It will be a thing. In addition, the porous sound absorbing function of the foamed resin base material provides an interior part with excellent sound absorbing performance. The rib thickness can be varied as appropriate, for example, by reducing the thickness of the rib at a portion where external force is relatively difficult to apply. 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 molding die used in the method of the present invention comprises a movable side die, a fixed side die, an injection machine, and a multifunctional block. For example, a molding upper mold capable of moving up and down by a predetermined stroke, a molding lower mold positioned below the molding upper mold, an injection machine connected to the molding lower mold, and a multifunctional mold disposed in the molding upper mold It is composed of blocks. 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, the shear block disposed along the outer periphery of the cavity portion of the molded lower mold is made of a synthetic resin material such as polyamide resin (nylon or the like), fluororesin (Teflon (registered trademark) or the like), polyacetal resin, or the like. Alternatively, a relatively soft light metal material such as aluminum or zinc is used. Moreover, as the shear clearance between the shear block and the inner wall surface of the molding upper mold, a reference value of 0.4 to 0.5 mm is set, and this reference value depends on the thickness of the decorating material. . Furthermore, when the shear block used in the present invention is employed, it is possible to absorb a variation of about the reference value ± 0.2 mm.

  Therefore, according to the method of the present invention, it is only necessary to mold the resin ribs 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, and the load on the molding die is reduced. In addition, the resin material can be saved, and the cooling time can be shortened compared to the conventional resin core material, so that the product molding cycle can be shortened.

  Furthermore, for the terminal portion along the outer periphery of the product of the laminated structure, since the cutting process along the trim cut line is performed by the shearing action between the molding lower mold and the shear block at the time of molding the foamed resin base material, At the same time, the cut processing of the end material of the foamed resin base material is completed, and after molding, it is removed from the molding die, and it is only necessary to wind up the decorative material winding wrap around the back surface of the foamed resin substrate. The entrainment process can be performed easily and with good appearance.

  Next, in a preferred embodiment of the present invention, the shear block disposed on the outer periphery of the cavity of the molded lower mold is composed of a stepped shear block in which a step portion is formed on the outer surface, and a molded upper and lower mold At the time of tightening, trim cut processing of the foamed resin sheet is performed between the upper corner portion of the stepped shear block and the inner wall surface of the molding upper die, and the lower corner portion of the stepped shear block and the inner wall surface of the molding upper die The trim cutting process of the decorating material is performed between the foamed resin base material and the trim cutting process of the decorating material in the same pressing process.

  Here, in the stepped shear block in which the step portion is formed on the outer surface of the shear block, the shear clearance at the upper corner portion is about 0.4 mm, the shear clearance at the lower corner portion is 0.2 mm or less, The interphase distance with the lower corner is set so as to ensure a winding dimension of 5 mm or more.

  And according to this embodiment, the trim cut processing of the foamed resin sheet can be performed by the shearing action between the upper corner portion of the stepped shear block and the inner wall surface of the molding upper mold, and the lower corner of the stepped shear block The trim cut processing of the decorating material is performed by the shearing action between the portion and the inner wall surface of the molding upper mold, and therefore the trim cut processing of the foamed resin base material and the decorating material can be performed in the same pressing process.

  As described above, the interior parts for automobiles obtained by the method of the present invention are lightweight and have a foamed resin base material having shape retaining properties, the back surface of the foamed resin base material, and the rigidity of the outer peripheral edge of the product. Because it is composed of resin ribs that are laminated and integrated at the required site, 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. Since it is a cost and porous material, it has an effect of excellent sound absorption performance.

  Furthermore, according to the method for manufacturing an automotive interior part according to the present invention, the foamed resin base material is molded into a required shape along the cavity shape of the molding die, and at the same time, the resin rib is formed on the back surface side of the foamed resin base material. Since the projected area of the resin rib, which is a resin molded body, is small, the load applied to the molding die is less than that of the conventional resin core material, and the cooling time can be shortened. Since it can be increased, the working efficiency can be increased, and in addition, there is an effect that a significant cost reduction can be brought about.

  Further, according to the method for manufacturing an automotive interior part according to the present invention, when clamping the molded upper and lower molds, due to the shear action between the shear block arranged in the molded lower mold and the inner wall surface of the molded upper mold, The trim cut process is performed at the same time as the molding of the foamed resin base material. In particular, by using a resin material or a light metal material as the shear block material, the variation in shear clearance can be absorbed. In addition to the fact that the base material is surely cut and the decorative material is not cut accidentally, the processing accuracy can be increased, and in addition, the shear clearance tuning operation can be simplified.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of a method for manufacturing an interior component for automobile according to the present invention will be described in detail with reference to the accompanying drawings. It should be noted 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 a first embodiment of the present invention. FIG. 1 is a front view showing a door trim manufactured by applying the method of the present invention. FIG. 2 is a sectional view showing the structure of the door trim. Is an explanatory view showing the pattern shape of the resin rib in the door trim, FIG. 4 is a cross-sectional view showing the configuration of the terminal processing portion in the door trim, and FIGS. 5 and 6 are molding dies 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 terminal processing portion of the door trim in the molding die. FIGS. 7 to 12 show the respective steps in the method for manufacturing the automobile door trim, FIG. 7 is an explanatory view showing the preheating step of the foamed resin sheet, and FIG. 8 shows the interior of the decorative material and the foamed resin sheet. FIG. 9 is an explanatory view showing the press forming step of the foamed resin base material, FIG. 10 is an explanatory view showing the trim cutting step in the foamed resin base material, and FIG. 11 is a resin rib forming step. Explanatory drawing and FIG. 12 are explanatory drawings which show the winding process of the decorating material in the door trim.

  1 and 2, an automotive door trim 10 is configured by attaching various functional parts to a door trim main body 20 formed into a desired curved surface shape. Specifically, an inside handle escutcheon 30 is attached to the inscribed portion of the door trim main body 20, and an armrest 31 swelled by an occupant who bulges indoors rests on the elbow in the middle of the door trim main body 20. A pull handle unit 32 and a power window switch escutcheon 33 are attached to the upper surface of the armrest 31, and a door pocket 34 that can accommodate equipment is provided below the armrest 31. A speaker grill 35 is attached to the door trim main body 20 or separately.

  As shown in FIG. 2, the door trim main body 20 is molded into a desired curved surface shape, and has a foamed resin base material 21 having a shape retaining property, 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 molded on the surface side of the foamed resin base material 21. The foamed resin base material 21 is subjected to heat softening treatment of 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. About the expansion | deployment rate part, you may shape the foamed resin base material 21 using vacuum forming together.

  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 pattern shapes may be selected if it is cross shape, 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 molding, and as a synthetic resin that can be preferably used usually, 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 main body 20 in the door trim 10 shown in FIGS. 1 to 3 includes a foamed resin base material 21 having shape retention, a resin rib 22 integrated on the back surface of the foamed resin base material 21, and a decoration. In addition to using the lightweight foamed resin base material 21, the resin core material occupied over the entire surface of the product can be abolished. The resin rib 22 has a bone-like shape, and a portion to which a load is applied, for example, a portion excluding the clip seat, the upper surface of the waist portion, the upper surface of the armrest portion, etc. has a thinning structure. Compared to the above, the weight can be reduced by 40% or more, and the resin material can be greatly saved, thereby contributing to the cost reduction.

  Furthermore, since the foamed resin base material 21 has a porous structure, the door trim main body 20 is excellent in sound absorbing performance and can reduce noise in the passenger compartment. Moreover, in order to maintain the sound absorption property of the foamed resin base material 21, the decorating material 23 laminated in advance on the surface of the foamed resin base material 21 or integrated and laminated at the time of molding is a woven fabric or a non-woven fabric. A sheet material having air permeability such as a knitted fabric is preferable. The decorative material 23 may be a synthetic resin sheet such as a PVC 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 this embodiment, a laminated sheet material made of cloth 23a, polyurethane foam 23b, and back nonwoven fabric 23c is used. In addition, when a TPO sheet is used in this way, it is advantageous in terms of recycling if it is unified with an olefin resin material.

  And the outer periphery terminal structure of the door trim main body 20 in the door trim 10 is demonstrated based on FIG. That is, in the door trim main body 20, as described above, the resin ribs 22 having a predetermined pattern shape for reinforcing rigidity are integrated with the back surface of the lightweight foamed resin base material 21 having shape retention, and the foam resin base material 21 is integrated. A decorative material 23 having a decorative property is laminated and integrated on the surface. Further, along the product outer periphery of the door trim main body 20, a vertical wall portion 24 for making the product appear three-dimensional is formed in a stepped flange shape, and the outer peripheral terminal portion is wound around the decorative material 23. 25 is wound on the back side of the foamed resin base material 21 and the cut end of the foamed resin base material 21 is not exposed, so that the appearance of the product is maintained well. Are in contact with each other.

  Next, the outline | summary of the manufacturing method of the door trim 10 including the terminal processing process of the outer periphery terminal part of the door trim main body 20 is demonstrated below. First, the overall structure of the molding die 40 will be described with reference to FIG. 5, and the main part of the molding die 40 corresponding to the outer peripheral portion of the door trim body 20 will be described with reference to FIG. 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. And an injection machine 43 connected to the main body.

  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, 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 via the manifold 422 and the gate 423 is the core portion. Supplied into a groove 424 formed on the upper surface of 421. In addition, guide posts 425 that serve as a guide mechanism protrude from the four corners of the molded lower mold 42, and the guide posts 425 are guided 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. The molding lower mold 42 is provided with a set frame 44 for setting the material, and the set frame 44 moves up and down in conjunction with the vertical movement of the molding upper mold 41.

Next, FIG. 6 shows a portion corresponding to the outer peripheral end portion of the door trim main body 20 in the molding die 40, and the shear block 50 is arranged along the outer periphery of the core portion 421 of the molded lower die 42. The shear block 50 is set so as to ensure an appropriate shear clearance with the inner wall surface of the molding upper die 41. In particular, in the present invention, as the material of the shear block 50, polyamide resin, fluorine It is characterized by using as a raw material a resin material such as resin or polyacetal resin, or a soft light metal such as aluminum or zinc. In this embodiment, the shear clearance indicated by the symbol d in FIG. 6 is set with a reference value of 0.4 to 0.5 mm. In this embodiment, as the decorating material 23, a cloth 23a, polyurethane foam is used. 23b, and a laminated sheet material having a thickness of 3.5 mm is used, which is made of a non-woven fabric on the back surface (weight per unit area 30 g / m ² ) 23c. For this reason, in this example, the shear clearance d is 0. It is set in the range of 4 to 0.5 mm. In particular, since a resin material or a light metal material is used as the material for the shear block 50, variations in shear clearance during trim cut of the foamed resin sheet can be absorbed. The shear block 50 can be easily attached and fixed to the molded lower mold 42 by inserting the screws 52 into the screw holes 51 and tightening and fixing them in the screw holes of the molded lower mold 42. . Further, the shear clearance d is set between the corner portion 53 of the shear block 50 and the inner wall surface of the molding upper die 41.

  In this embodiment, the decorating material 23 having a thickness of about 3.5 mm is used. However, the dimension of the shear clearance d can be varied according to the material and thickness of the decorating material 23. In particular, when a soft material is set in the shear block 50 as in the present embodiment, it can be handled with a relatively rough accuracy of about a reference value ± 0.2 mm.

  Next, each step in the method for manufacturing the door trim 10 will be described with reference to FIGS. First, as shown in FIG. 7, the foamed resin sheet S is heat-softened to a high temperature of 160 to 220 ° C. by the heater device 60. 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. Subsequently, as shown in FIG. 8, the decorative material 23 and the above-described heat-softened foamed resin sheet S are put into the mold when the upper and lower molds 41 and 42 are in the mold open state. Specifically, the decorating material 23 is preferably held by a set pin (not shown) in the lower stage of the molding upper die 41 or by a vacuum suction force by a vacuum suction mechanism attached to the molding upper die 41. It may be placed on the upper surface of the resin sheet S. On the other hand, the foamed resin sheet S may be placed on the upper surface of the set frame 44 that is provided around the outer periphery of the core portion 421 at a predetermined distance.

  Thereafter, the elevating 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 as shown in FIG. The foamed resin base material 21 is molded into a required shape. At this time, as shown in FIG. 10, at the outer peripheral end portion of the door trim main body 20, the end material Sa of the foamed resin sheet S is cut and removed by the shearing action between the shear block 50 and the inner wall surface of the molding upper die 41. Therefore, trim cut processing is performed in the same process as press molding. Further, as described above, since the shear block 50 is made of a resin material or a light metal material, the shear clearance d between the corner portion 53 of the shear block 50 and the inner wall surface of the molding upper die 41 is a reference. Since an error of about ± 0.2 mm can be absorbed, the end material Sa of the foamed resin sheet S can be surely cut and removed, and the decorating material 23 is not cut by mistake, and an accurate cutting process is performed. It is.

  After the molding of the foamed resin base material 21, as shown in FIG. 11, the molten resin M is injected and filled into the groove portion 424 from the injection machine 43 through the manifold 422 and the gate 423, and the resin rib 22 becomes the foamed resin base material 21. The door trim body 20 is completely molded in a predetermined pattern shape at a predetermined position on the back surface of the door trim. Thereafter, after the upper mold 41 is raised and the mold is opened, the door trim main body 20 is removed, and as shown in FIG. After the end material 23d of the decorating material 23 is cut so as to be able to, as shown in FIG. 12 (b), the winding white 25 is wound on the back side of the foamed resin base material 21, and heat welding, The terminal treatment is completed by adhering by ultrasonic welding, adhesive stop, or the like.

  Therefore, since the end material Sa can be cut and removed simultaneously with the molding of the foamed resin base material 21 without requiring a separate cutting step of the foamed resin base material 21 as in the prior art, the terminal processing work can be performed efficiently. it can. In the first embodiment, the molding step of the foamed resin base material 21 and the injection filling step of the resin rib 22 are performed using the molding upper and lower molds 41 and 42 described above. After molding the foamed resin base material 21 and the resin rib 22, respectively, the both may be pressure-bonded and fixed by a pressure-bonding die. Further, in the first embodiment, the method of the present invention is applied to the door trim body 20 in the integrated door trim 10, but the present invention can also be applied to a door trim upper in a vertically divided door trim.

  FIGS. 13 to 15 show a second embodiment of the present invention, and a description of the same parts as those in the first embodiment will be omitted. In the second embodiment, the shape of the shear block 50 is different from that of the first embodiment, so that the trim cut process of the foamed resin base material 21 and the trim cut process of the decorating material 23 are performed simultaneously with the molding of the foamed resin base material 21. It is characterized by being performed in the same process. That is, as shown in FIG. 13, in the second embodiment, the shear block 50 disposed on the outer periphery of the core portion 421 of the molded lower mold 42 has two upper corner portions 53A and lower corner portions 53B on the outer surface. A stepped shear block 50A having two corner portions 53A and 53B is used.

  As the material of this stepped shear block 50A, as in the first embodiment, a soft material, that is, a resin material such as polyamide resin, fluororesin, polyacetal resin, or light metal material such as aluminum or zinc is used. In particular, as shown in FIG. 13, the shear clearance d1 between the upper corner portion 53 </ b> A and the inner wall surface of the upper molding die 41 is 0.4 mm, and between the lower corner portion 53 </ b> B and the inner wall surface of the molding upper die 41. The shear clearance d2 is set to 0.2 mm or less, and the interphase distance (indicated by symbol h in the figure) between the upper corner portion 53A and the lower corner portion 53B is set to 5 mm or more. The interphase distance h corresponds to the size of the winding white 25 in the decorative material 23.

  Therefore, when the stepped shear block 50A is arranged on the molding lower mold 42 side, as shown in FIG. 14, when the door trim body 20 is molded, the foamed resin sheet S is molded into a desired curved shape, and at the same time, The excess foamed resin sheet Sa is cut and removed between the upper corner portion 53A of the attached shear block 50A and the inner wall surface of the molding upper die 41. Further, the end material 23d of the decorating material 23 is cut and removed between the lower corner portion 53B of the stepped shear block 50A and the inner wall surface of the molding upper die 41. Also in this case, since the stepped shear block 50A is made of a soft material, the same effect as the first embodiment can be expected that the shear clearances d1 and d2 can be managed relatively roughly. Moreover, about the lower corner part 53B, the shaping | molding lower mold | type 42 can be extended and formed and it can also respond with steel materials.

  Therefore, in the second embodiment, after the door trim body 20 is molded, the molded upper and lower molds 41 and 42 are opened, the door trim body 20 is removed from the molded upper and lower molds 41 and 42, and the winding scissors 25 are removed. After the winding operation on the back side of the foamed resin base material 21, the terminal treatment can be performed by fixing with an adhesive, heat welding, ultrasonic welding or the like, and the cut processing of the decorative material 23 is also abolished. Therefore, there is an advantage that the terminal processing work can be simplified.

  In the first and second embodiments described above, the present invention is applied to the method of manufacturing the door trim main body 20 in the automobile door trim 10. However, the method of the present invention can be applied to the door trim upper in the upper and lower split type door trim. In addition, as interior parts other than the door trim 10, the present invention can be applied to general interior parts for automobiles such as a rear parcel shelf, a floor trim, a trunk trim, a luggage trim, a roof trim, and a rear side trim.

It is a front view which shows the door trim for motor vehicles manufactured by applying the method of this invention. It is the II-II sectional view taken on the line in FIG. It is a front view which shows the pattern shape of the resin rib 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 showing a molding die used in the method for manufacturing the automobile door trim shown in FIG. 1. It is sectional drawing which shows the site | part corresponding to the terminal process part of the door trim main body in the molding 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 decorating material and a 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 in the manufacturing method of the door trim for motor vehicles shown in FIG. It is explanatory drawing which shows the trim cut process of the foaming resin base material 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 terminal process process of the door trim main body in the manufacturing method of the door trim for motor vehicles shown in FIG. It is principal part sectional drawing which shows the shaping die used for 2nd Example of this invention. It is explanatory drawing which shows the formation process of the door trim main body in 2nd Example of this invention. It is explanatory drawing which shows the terminal process process of the door trim main body in 2nd Example of this invention. It is a front view which shows the conventional door trim for motor vehicles. It is the XVII-XVII sectional view taken on the line in FIG. It is a schematic diagram which shows the shaping die which shape | molds the conventional door trim. It is explanatory drawing which shows the prior art example of the terminal part in the door trim for motor vehicles by press molding. It is explanatory drawing which shows the prior art example of the terminal part in the door trim for motor vehicle of a skin-wrapping type.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Door trim for motor vehicles 20 Door trim main body 21 Foamed resin base material 22 Resin rib 23 Decorating material 24 Vertical wall part 25 Roll-in white 40 Molding die 41 Molding upper mold 42 Molding lower mold 43 Injection machine 50, 50A Sher block 51 Screw hole 52 Screw 53 Corner portion 53A Upper corner portion 53B Lower corner portion S Foamed resin sheet M Molten resin

Claims (2)

A foamed resin base material (21) which is molded into a required shape and is lightweight and has shape retention, a resin rib (22) having a predetermined pattern shape integrated with the back surface of the foamed resin base material (21), In a method for manufacturing an interior part (10) for an automobile, in which a laminated structure (20) composed of a decorating material (23) attached to the surface of a foamed resin substrate (21) is employed in whole or in part. ,
When the molded upper and lower molds (41, 42) are opened, the laminated structure (20) includes the decorative material (23) and the heat-softened foamed resin sheet (S) in the molded upper and lower molds (41, 42). The process of setting the material to be set;
The molding upper and lower molds (41, 42) are clamped, and the foamed resin sheet (S) is press-molded into a desired curved shape along the cavity shape of the molding die (40), and the molding lower mold (42) Trim cut processing of the foamed resin sheet (S) with a predetermined dimension by the shearing action between the shear block (50) made of a resin material or light metal material arranged on the outer periphery of the cavity and the inner wall surface of the molding upper die (41) Thereafter, the molten resin (M) is injected and filled into the groove portion (424) of the molded lower mold (42) either before or after the mold clamping of the molded upper and lower molds (41, 42). The step of forming the laminated structure in which the resin rib (22) is integrated with the back surface side of the foamed resin base material (21) to form the laminated structure (20),
After the mold upper and lower molds (41, 42) are opened, the laminated structure (20) is demolded, and then the decorative material (23) is wound around the back surface of the foamed resin base material (21) (25 ) Winding process of the decorative material (23) for winding process,
A method for manufacturing an interior part for an automobile, which is manufactured by a process comprising: The shear block (50) disposed on the outer periphery of the cavity of the molded lower mold (42) is composed of a stepped shear block (50A) having a stepped portion on the outer surface, and is formed of the molded upper and lower molds (41, 42). At the time of mold clamping, the trim cut processing of the foamed resin sheet (S) is performed between the upper corner portion (53A) of the stepped shear block (50A) and the inner wall surface of the molded upper die (41), and the stepped shear The trim cut processing of the decorating material (23) is performed between the lower corner portion (53B) in the block (50A) and the inner wall surface of the molding upper die (41), the foamed resin base material (21), the decorating material (23) The method for manufacturing an automotive interior part according to claim 1, wherein both trim cut processes are performed in the same pressing step.

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