JP6377909B2 - Mold for foam molding in olefin resin mold - Google Patents

Description

  The present invention relates to a mold for foam molding in an olefin-based resin mold suitable for molding a foam molded body with a fastener.

  Conventionally, a vehicular seat is generally produced by integrally molding a metal wire for stabilizing the shape into a buried body in a seat body made of polyurethane. In recent years, as a polyurethane structure that improves passenger comfort, the surface layer has been softened to relieve the pressure that the human body receives from the seat, and the lower part is made of polyurethane with relatively high synthesis and has a different hardness A sheet has been proposed (see, for example, Patent Document 1).

  On the other hand, from various viewpoints such as environmental issues, passenger safety (anti-submarine), vehicle weight reduction, and cost reduction, it is not a combination of polyurethane of different hardness but a combination of polyurethane and polyolefin resin foam A vehicle seat has been proposed (see, for example, Patent Document 2). Polyolefin-based resin foam has features such as arbitrary shape, lightness, and heat insulation, and is used in various applications such as heat insulating materials, shock-absorbing packaging materials, automobile interior members, and core materials for automobile bumpers. By using a high-strength polyolefin-based resin foam for the vehicle seat, the shape can be stabilized, and the metal wire that is essential for the shape stabilization in the configuration of only polyurethane is not necessary. However, since a U-shaped hook is required when attaching the vehicle seat to the vehicle, it is necessary to leave a metal wire as an anchor material for fixing the U-shaped hook to the vehicle seat.

  There are two main methods for constructing a vehicle seat with a polyolefin resin foam and polyurethane. One method is to mold a polyolefin resin foam containing metal wires in advance, In this method, the polyolefin resin foam is attached to a mold and is integrally molded with polyurethane. Another method is a method in which a polyolefin resin foam and polyurethane are separately molded, and these are combined (for example, see Patent Document 3). From the viewpoint of the beauty of the product and the sense of unity of urethane and olefin resin foam, it is preferable to integrally mold the polyolefin resin foam and polyurethane as in the former case.

  In addition, there are two methods of incorporating metal wires into polyolefin resin foams. One method is to set metal wires in a mold for in-mold foam molding and foam the metal wires into polyolefin resin foam. This is a method of integrally molding with the body. As another method, there is a method in which a space for attaching a metal wire is formed in the foam body by devising a polyolefin resin foam shape, and the metal wire and the foam are combined after molding. From the viewpoint of reducing the manufacturing cost and firmly fixing the metal wire in the foam, it is preferable to integrally mold the metal wire and the polyolefin resin foam as in the former.

  In addition, as a technology for integrally molding a load-bearing frame embedded in a cushion pad made of urethane resin foam, positional displacement in the direction along the inner wall is regulated by a plurality of positioning members protruding from the inner wall of the upper mold However, a cushion pad manufacturing method has been proposed in which a plurality of magnets arranged on the inner wall of the upper mold are held so as not to fall, and in this state, the mold is closed and foam molding is performed ( For example, see Patent Document 4.)

JP 2006-34945 A JP 2001-161508 A JP 2011-111131 A JP 2006-20735 A

  When molding a foamed molded product with a fastener that is made by fixing a fastener such as a U-shaped hook to the foam with an anchor material such as a metal wire, such as a vehicle seat made of polyolefin resin foam. The problems are the dimensional stability of the product and the deformation of the product derived from the anchor material made of metal wire.

  A general metal wire having an outer shape of 4 mm or more and 5 mm or less is often used, but there is a tendency to elastically deform with a relatively small external force. Furthermore, since the processing surface of the metal wire has a variation of processing accuracy of about ± 2mm in the approximate dimension of the vehicle seat size, when the metal wire is simply fixed to the mold for polyolefin resin foam, the metal is forcibly forced. There are many cases that can be attached to the fixed fixture of the mold.

  In general, since the material for foam molding in the mold is aluminum and the material of the metal wire is iron, the inside of the mold is heated during molding due to the difference in linear expansion due to the material of the mold and the metal wire. In this case, it is assumed that the positions of the two are shifted and the metal wire is deformed.

  Thus, when a deformation | transformation arises in a metal wire before shaping | molding or at the time of shaping | molding, a metal wire will elastically recover after shaping | molding and will return to an original shape. At that time, since the polyolefin resin foam is pulled by the metal wire, a warp-like deformation occurs in the polyolefin resin foam.

  When a vehicle seat is formed by integrally molding with polyurethane using the polyolefin resin foam in which such deformation has occurred, there is a problem that the injected polyurethane resin leaks around and flows around a predetermined place. Occur. In addition, there is a problem that the polyolefin resin foam and urethane are not integrally molded, and are not assembled properly even if they are laminated or combined after molding.

  On the other hand, in the manufacturing method described in Patent Document 4, foam molding can be performed in such a way that distortion and residual stress of the load bearing frame does not remain by using the positional relationship between the cushion material body and the load bearing frame. However, it is not a molding method using in-mold foam molding using polyolefin-based foamed resin, and the fastener to the vehicle body is embedded in the cushion material body made of urethane resin foam, so the position of the cushion material body and the load-bearing frame There is a problem that it becomes difficult to find a fastener due to a shift in the relationship, or that the accuracy of assembling the cushion material to the vehicle body is lowered.

  An object of the present invention is to prevent deformation of a molded body with a fastener due to the anchor material trying to return to its original shape after in-mold foam molding, and improve the dimensional stability of the molded body with a fastener. The present invention provides a mold for foam molding in an olefin resin mold.

  As a result of intensive studies in order to solve the above problems, the present inventors have fixed and held portions other than the reference position so as to be relatively movable with respect to the mold. Prevents deformation of the anchor material made of metal wire, etc. when assembling to the mold or in-mold foam molding of a molded product with a fastener, and the anchor material attempts to return to its original shape after in-mold foam molding The present invention has been completed by eliminating the need for deformation, preventing the deformation of the molded body with fasteners, and improving the dimensional stability of the molded body with fasteners.

  The mold for foam molding in an olefin resin mold according to the present invention includes an anchor material, a molded body fastening member having a plurality of fasteners attached to the anchor material, and a foam molded body made of a polyolefin foam resin. The molded body with a fastener is integrated by in-mold foam molding so that at least a part of the anchor material is embedded in the foam molded body and at least a part of the fastener is exposed to the outside from the foam molded body. In the mold to be molded, as a plurality of fixed holders that fix and hold the molded body fastening member with respect to the mold, a first fixed holder having a reference position holding portion that holds the fastener in a relatively unmovable manner; A plurality of second fixed holders having a displacement absorption holding part for holding an appropriate portion of the molded body fastening member spaced from the fastener so as to be relatively movable by a predetermined distance are provided.

  In this mold, the fastener of the molded body fastening member is held in the reference position holding portion of the first fixed holder so as not to be relatively movable, and an appropriate portion of the molded body fastening member is placed in the displacement absorbing portion of the second fixed holder. Is held so as to be relatively movable by a certain distance. Therefore, when the molded body fastening member is assembled to the mold, the molded body remains in the same posture as the initial posture before assembly to the mold, that is, without forcibly deforming the molded body fastening member. Due to the difference in linear expansion between the mold and anchor material when the foamed molded body is foam-molded in the mold after the molded body fastening member can be assembled to the mold The relative movement between the mold and the anchor material can be absorbed by the displacement absorption holding part, and an excessive force does not act on the anchor material, so that the shape of the initial molded body fastening member before assembly to the mold is almost changed. The molded body with a fastener can be molded without any problems. Therefore, it is possible to eliminate the need for the anchor material to be deformed in an attempt to return to its original shape after in-mold foam molding, to prevent deformation of the molded body with the fastener, and to improve the dimensional stability of the molded body with the fastener. Although it is possible to hold the portion other than the fastener of the molded body fastening member in the reference position holding portion, in order to improve the assembly accuracy of the molded body with the fastener to the assembly target such as a vehicle, It is preferable to hold the fastener with respect to the position holding portion.

  The reference position holding part may be provided with a concave part that fits into the fastener without a gap, or the displacement absorption holding part may be provided with a concave part that fits with a gap with respect to the molded body fastening member. it can. By comprising in this way, a molded object fastening member can be assembled | attached to the appropriate position of a metal mold | die by the groove part of a simple structure.

  It is preferable that a gap on one side between the inner surface of the concave portion serving as the displacement absorption holding portion and the anchor material or fastener fitted thereto is 0.5 mm or more and 3.0 mm or less. By constituting in this way, the deformation of the molded product fastening member is absorbed while preventing the raw material beads from leaking out of the molding space from the inner surface of the recess as the displacement absorption holding portion and the gap between the anchor material or the fastener. be able to.

  It is also a preferred embodiment that the anchor material is composed of a metal wire, and that the fastener is composed of a U-shaped hook. As the anchor material and the fastener, those having an appropriate configuration can be adopted according to the product form to be molded. For example, as the anchor material, an elongated pipe shape, bar shape, plate shape, square shape made of a metal material or a synthetic resin material is used. A plate shape such as a rectangular shape or any other shape can be employed, and a hook member having a known shape such as a U-shape or a J-shape can be employed as a fastener.

  In a preferred embodiment, a magnet for attracting and holding the molded body fastening member is provided on the fixed holder. If comprised in this way, a molded object fastening member can be fixed to a fixed holding tool with a magnet, allowing the relative movement of a fixed holder and a molded object fastening member.

  One of the molds is provided with an urging means for urging the fixed holder toward the other mold, and the other mold is in contact with the tip of the fixed holder. In a preferred embodiment, a surface is formed and the mold is closed so that the molded body fastening member can be sandwiched between the distal end portion of the fixed holder and the contact surface. In this case, even when the mold is closed, the fixed holder and the abutting surface are molded between the fixed holder and the abutting surface by the urging force of the urging means while allowing the relative movement of the molded body fastening member. A body fastening member can be clamped.

  The molded body with a fastener is preferably a vehicle seat core. In the mold according to the present invention, a molded product having an arbitrary configuration can be manufactured as long as the molded body fastening member is integrally molded with the foam molded body by in-mold foam molding. For example, automobile interior members such as vehicle seat cores, bumper cores, and headrest cores can be suitably manufactured.

  According to the mold for foam molding in an olefin-based resin mold according to the present invention, when the molded body fastening member is assembled to the mold, the posture is substantially the same as the initial posture before the assembly to the mold, That is, the molded body fastening member can be assembled to the mold without forcibly deforming the molded body fastening member, and after the molded body fastening member is assembled to the mold, the foam molded body is subjected to in-mold foam molding. In this case, the relative movement between the mold and the anchor material due to the difference in linear expansion between the mold and the anchor material can be absorbed by the displacement absorbing holder, and no excessive force is applied to the anchor material. A molded body with a fastener can be molded without substantially changing the shape of the initial molded body fastening member before attachment. Therefore, it is possible to eliminate the need for the anchor material to be deformed in an attempt to return to its original shape after in-mold foam molding, to prevent deformation of the molded body with the fastener, and to improve the dimensional stability of the molded body with the fastener.

Perspective view with the molded body with fasteners installed vertically Bottom view of molded body with fasteners Sectional view along line III-III in Fig. 2 Vertical section of in-mold foam molding equipment (A) Front view on the concave mating surface side, (b) Front view on the convex mating surface side Sectional view taken along line VI-VI in FIG. 5A is a cross-sectional view taken along the line VII-VII in FIG. 5B, and FIG. 5B is a cross-sectional view taken along the line VII-VII in FIG. Front view of convex fitting surface side of first fixing holder (A) is a front view of the convex mating surface side of the second fixed holder disposed in the molding space, and (b) is a second fixed holder for fixing and holding the anchor material disposed outside the molding space. The front view on the convex mating surface side, (c) is a front view on the convex mating surface side of the second fixed holder for fixing and holding the third fastener arranged outside the molding space.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, the structure of the molded object with a fastener shape | molded with the metal mold | die which concerns on this invention is demonstrated. In the present embodiment, a case where a vehicle seat core material is molded as a molded body with a fastener will be described.

  As shown in FIGS. 1 to 3, the molded body 1 with a fastener includes an anchor material 2, a molded body fastening member 4 having a plurality of fasteners 3 attached to the anchor material 2, and a molded body fastening member 4. A foam molded body 5 made of a polyolefin-based foamed resin, and at least a part of the anchor material 2 is embedded in the foam molded body 5, and at least a part of the fastener 3 is exposed to the outside from the foam molded body 5. Thus, it is integrally molded by in-mold foam molding. FIG. 1 is a perspective view of a car seat cushion core material (hereinafter referred to as “sheet core material”) as a molded body 1 with a fastener in a vertically placed state. The molded body 6 made of polyurethane is integrally formed on the upper side of the foam molded body 5 as indicated by phantom lines.

  More specifically, the foam molded body 5 is configured in a thick U-shaped plate having a size suitable for a seat cushion. The anchor material 2 is a metal wire made of iron, stainless steel or the like bent into a rectangular frame shape and welded at both ends. The upper and lower anchors arranged on the upper side will be described with reference to FIG. 2a and the upper portions of the side anchors 2b and 2c arranged on both the left and right sides are provided embedded in the foam molded body 5 along the outer surface of the foam molded body 5, and the left and right side anchors 2b and 2c The lower part and the lower anchor 2d arranged on the lower side protrude downward from the foamed molded body 5 and are exposed to the outside. A pair of upper and lower mounting plates 7A and 7B are fixed to the left side anchor 2b with a space therebetween, and one mounting plate 7C is fixed to the center in the height direction of the right side anchor 2c. These three mounting plates 7A to 7C are provided in the foamed molded body 5 so as to be embedded. A first fastener 3A composed of a U-shaped hook projecting forward (downward when assembled to the vehicle body) is fixed to the upper left mounting plate 7A, and the front portion of the first fastener 3A is a foam molded body. Projecting forward from 5. A second fastener 3B made of a U-shaped hook projecting forward (downward when assembled to the vehicle body) is fixed to the lower left mounting plate 7B, and the front portion of the second fastener 3B is a foam molded body. Projecting forward from 5. A third fastener 3C composed of a U-shaped hook projecting to the right is fixed to the right mounting plate 7C, and the right portion of the third fastener 3C projects rightward from the foamed molded body 5, and the fastener The attached molded body 1 is fixed to the vehicle body by fixing these three fasteners 3A to 3C to members on the vehicle body side. In the present specification, the fasteners 3A to 3C may be collectively referred to as the fastener 3, and the attachment plates 7A to 7C may be collectively referred to as the attachment plate 7.

  The anchor material 2 is made of a metal material such as iron or stainless steel, a long and narrow pipe shape, a rod shape or a plate shape, a plate shape such as a square or a rectangle, or any other shape. Can be adopted. In addition, the anchor material 2 can be configured in an arbitrary frame shape according to the sheet shape as long as it has a function for fixing the fastener 3 to the foamed molded body 5. It is also possible to configure in a U shape. Further, the exposed portion of the anchor material 2 from the foamed molded body 5 can be appropriately set according to the shape of the vehicle seat or the like, or can be configured not to be exposed. Further, the number, the arrangement position, and the shape of the fasteners 3 can be arbitrarily set according to the configuration on the vehicle side. Further, although the fastener 3 is fixed to the anchor material 2 via the mounting plate 7, the fastener 3 can be directly fixed to the anchor material 2.

  The size and shape of the foam molded body 5 can be configured in an appropriate shape according to the size and shape of the vehicle seat. The polyolefin resin constituting the foamed molded product 5 is a polymer containing 75% by weight or more of an olefin monomer.

(Polyolefin resin)
Specific examples of the olefin monomer include, for example, ethylene, propylene, butene-1, isobutene, pentene-1, 3-methyl-butene-1, hexene-1, 4-methyl-pentene-1, 3, 4 Examples thereof include α-olefins having 2 to 12 carbon atoms such as dimethyl-butene-1, heptene-1, 3-methyl-hexene-1, octene-1, and decene-1. These may be used alone or in combination of two or more.

  Specific examples of other monomers copolymerizable with the olefinic monomer include, for example, cyclopentene, norbornene, 1,4,5,8-dimethano-1,2,3,4,4a. , 8,8a, 6-octahydronaphthalene and the like, 5-methylene-2-norbornene, 5-ethylidene-2-norbornene, 1,4-hexadiene, methyl-1,4-hexadiene, 7-methyl-1 , 6-octadiene and the like. These may be used alone or in combination of two or more.

  Specific examples of the polyolefin resin include, for example, polyethylene resins mainly composed of ethylene such as high density polyethylene, medium density polyethylene, low density polyethylene, and linear low density polyethylene, and polypropylene resins mainly composed of propylene. Is mentioned. These polyolefin resins may be used alone or in combination of two or more.

  The polypropylene resin is not particularly limited as long as it contains propylene as a main component of the monomer. For example, propylene homopolymer, α-olefin-propylene random copolymer, α-olefin-propylene block copolymer Etc. These may be used alone or in combination of two or more.

  In particular, since the α-olefin is ethylene, a polypropylene-based resin containing ethylene as a comonomer component is easily available and excellent in process moldability, so that it can be used for in-mold foam molding. Liked.

  The polypropylene resin is not particularly limited as long as it contains propylene as a main component of the monomer, and examples thereof include a propylene homopolymer, an olefin-propylene random copolymer, and an olefin-propylene block copolymer. .

These may be used alone or in combination of two or more.
Examples of the polyethylene resin used in the present invention include ethylene homopolymer, ethylene-α-olefin random copolymer, ethylene-α-olefin block copolymer, low density polyethylene, high density polyethylene, and linear low density polyethylene. Is mentioned. The α-olefin referred to herein includes α-olefins having 3 to 15 carbon atoms, and these may be used alone or in combination of two or more.

  Among these polyethylene-based resins, good foamability when ethylene-α-olefin block copolymer has a comonomer content other than ethylene of 1 to 10% by weight or is a linear low density polyethylene And can be suitably used for in-mold foam molding.

  The polyolefin-based resin used in the present invention further includes a cell nucleating agent such as talc, an antioxidant, a metal deactivator, a phosphorus-based processing stabilizer, an ultraviolet absorber, an ultraviolet stabilizer, and a fluorescence as necessary. Brighteners, stabilizers such as metal soaps, or crosslinking agents, chain transfer agents, lubricants, plasticizers, fillers, reinforcing agents, inorganic pigments, organic pigments, conductivity improvers, flame retardant improvers, interfaces It can be used as a polyolefin resin composition to which an additive such as an activator type or a polymer type antistatic agent is added.

  The polyolefin resin composition used in the present invention is usually melted with an additive, if necessary, with a polyolefin resin in advance using an extruder, kneader, Banbury mixer, roll, etc. so as to be easily used for pre-foaming. The mixture is mixed and molded into a polyolefin resin particle having a desired particle shape such as a cylindrical shape, an elliptical shape, a spherical shape, a cubic shape, a rectangular parallelepiped shape, or the like.

  The method for producing the polyolefin resin pre-expanded beads used in the present invention is not particularly limited, but the polyolefin resin particles are dispersed in a dispersion medium in the presence of a foaming agent in a dispersion medium in the presence of a foaming agent. A method of releasing and foaming the dispersion in a sealed container to a low pressure region while maintaining the temperature and pressure in the container constant, after heating to a predetermined foaming temperature under pressure and impregnating the resin particles with a foaming agent, So-called decompression foaming is preferred.

  The heating temperature in the sealed container is preferably the melting point of polyolefin resin particles −25 ° C. or higher and the melting point of polyolefin resin particles + 25 ° C. or lower, more preferably the melting point of polyolefin resin particles −15 ° C. or higher and the melting point of polyolefin resin particles +15. The temperature is in the range of ℃ or less. After heating and pressurizing to this temperature and impregnating the foaming agent into the polyolefin resin particles, one end of the sealed container is opened to release the polyolefin resin particles into a lower pressure atmosphere than in the sealed container. Thus, it is possible to produce polyolefin resin pre-expanded beads.

  In producing the polyolefin resin pre-expanded beads, the blowing agent is not particularly limited. For example, aliphatic hydrocarbons such as propane, isobutane, normal butane, isopentane, and normal pentane; inorganic gases such as air, nitrogen, and carbon dioxide; Water or the like and a mixture thereof can be used.

(Molding equipment)
Next, the configuration of the mold apparatus will be described.
As shown in FIGS. 4 to 6, the in-mold foam molding mold apparatus M includes a concave unit 10 having a concave mold 11 and a concave housing 12 that holds the concave mold 11, a convex mold 21, and a convex housing that holds the convex mold 21. And a holding unit 30 for fixing and holding the molded body fastening member 4 between the concave unit 10 and the convex unit 20. The molded body is fastened to the convex unit 20 by the fixed holding means 30. The member 4 is fixedly held, the concave unit 10 and the convex unit 20 are combined, and the embedded portion of the molded body fastening member 4 is fixed in the molding space CA formed by the concave mold 11 and the convex mold 21 as a mold. In the held state, the foaming resin particles are filled in the molding space CA, and the foaming resin particles are heated and foam-fused in the molding space CA, so that the molding body fixing member 4 is embedded in the foam molding body 5. Together Is obtained without to obtain a fastener with molded body 1 was shaped.

  The mold composed of the concave mold 11 and the convex mold 21 is made of a material having a low specific heat and a high thermal conductivity, for example, a casting made of an aluminum alloy so that the molded product can be smoothly heated and cooled. 22 is made of an iron-based metal in order to reduce the manufacturing cost of the mold apparatus M and to ensure sufficient strength and rigidity.

  The concave housing 12 includes a rectangular cylindrical concave frame 13, and a concave mold 11 fixed to the concave frame 13 via a center plate 14 so as to close an opening on the front side of the concave frame 13 (the mold mating surface side). And a concave back plate 15 for closing the opening on the back side of the concave frame 13, and a concave chamber 16 is formed in the concave housing 12 on the back side of the concave mold 11.

  The concave unit 10 is connected to a steam supply pipe 18a, a cooling water supply pipe 18b, and a drain pipe 18c that open into the concave chamber 16, and control valves 19a to 19c interposed in the middle of these pipes 18a to 18c. By operation, steam is supplied into the concave chamber 16 to heat and foam the foamable resin particles, or cooling water is sprayed from the nozzle 18d to the back side of the concave mold 11 to cool the molded product, or unnecessary drainage is removed. It can be discharged from the concave chamber 16. A large number of vent holes 11a are formed in the concave mold 11, and steam is supplied from the concave mold chamber 16 into the molding space CA through the vent holes 11a. A filler 17 is fixed to the concave back plate 15, and the tip of the filler 17 is inserted into the molding space CA through the concave mold 11, and the expandable resin particles are supplied from the filler 17 into the molding space CA. Thus, the molding space CA is filled. Although not shown, an ejector pin that can be inserted through the concave mold 11 and protrude into the molding space CA through the concave mold 11 is supported.

  The convex housing 22 is fixed to the convex frame 23 via the center plate 24 so as to close the rectangular cylindrical convex frame 23 and the opening on the front side of the convex frame 23 (the mating surface side of the mold). And a convex back plate 25 for closing the opening on the back side of the convex frame 23, and a convex chamber 26 is formed in the convex housing 22 on the back side of the convex mold 21. Yes.

  A steam supply pipe 28a, a cooling water supply pipe 28b, and a drain pipe 28c that open into the convex chamber 26 are connected to the convex unit 20, and control valves 29a to 29a interposed in the middle of these pipes 28a to 28c. By operating 29c, steam is supplied into the convex chamber 26 to heat and foam the foamable resin particles, or cooling water is sprayed from the nozzle 28d to the back side of the convex mold 21 to cool the molded product, An unnecessary drain can be discharged from the convex chamber 26. A large number of vent holes 21a are formed in the convex mold 21, and steam is supplied from the convex chamber 26 into the molding space CA through the vent holes 21a.

(Fixed holding means)
As shown in FIGS. 4 to 9, the mold composed of the concave mold 11 and the convex mold 21 according to the present invention is a fixed holding means 30 for fixing and holding the molded body fastening member 4 to the mold apparatus M as described above. A first fixed holding means 31 for holding the first fastener 3A of the molded body fastening member 4 so as not to move relative to the concave mold 11 and the convex mold 21 and a plurality of the molded body fastening member 4 spaced apart from the first fastener 3A. And a plurality of second fixing and holding means 40 for holding the location on the concave mold 11 and the convex mold 21 so as to be movable relative to each other by a certain distance. At least a part of the molded body fastening member 4 is disposed in the molding space CA. The molded body fastening member 4 can be integrally formed with the foam molded body 5. As the mold apparatus M, a configuration similar to that of the well-known mold apparatus M can be adopted with respect to the configuration other than the fixed holding means 30. Further, in the present embodiment, the first fastener 3A is set at the reference position, but the second fastener 3B or the third fastener 3C can also be set at the reference position. Further, the second fixing and holding means 40 is configured to absorb the relative movement of the concave mold 11 and the convex mold 21 and the molded body fastening member 4 in the direction orthogonal to the mold opening / closing direction. It can also be configured to absorb movement. In the present specification, the first fixed holding means 31 and the second fixed holding means 40 may be collectively referred to as a fixed holding means 30.

  As shown in FIGS. 4, 6, and 8, the first fixing and holding means 31 is a first fixing provided on the convex mold 21 side having the reference position holding portion 32 that holds the first fastener 3 </ b> A so as not to be relatively movable. A holding tool 33, a first biasing means 34 that biases the first fixed holding tool 33 so as to protrude toward the concave mold 11, and the concave mold 11 are provided so as to be able to contact the tip of the first fixed holding tool 33. The mounting plate 7A of the first fastener 3A is brought into contact with the distal end portion of the first fixed holder 33 in a state where the first fastener 3A is positioned and fitted to the reference position holding portion 32. The first fastener 3A is positioned and held between the concave mold 11 and the convex mold 21 so as not to be relatively movable by being sandwiched between the surfaces 39a by the biasing force of the first biasing means 34.

  The 1st fixing holder 33 is comprised with the flat pipe-shaped member made from metal, and the 1st accommodation recessed part 36 formed in the upper right toward the mating surface of the convex mold | type 21 as shown in FIG.5 (b). It is loaded so that it can move in the mold opening and closing direction. In the central portion of the first fixed holder 33, as a reference position holding portion 32, a first fastener 3A is fitted into the first fastener 3A so as not to be relatively movable so that it can be attached and detached without substantial gaps. A concave portion is formed. However, as the reference position holding portion 32, any configuration may be adopted according to the shape of the first fastener 3A and the like as long as the first fastener 3A can be held in a relatively unmovable manner. it can.

  As shown in FIGS. 4 and 6, the first urging means 34 penetrates through the bottom of the first housing recess 36 that houses the first fixing holder 33 and protrudes toward the back side of the convex mold 21. And a spring member 38 made of a compression coil spring that is externally attached to the guide rod 37 between the first fixed holder 33 and the bottom of the first receiving recess 36 and constantly biases the first fixed holder 33 toward the concave mold 11. ing. A stopper 37a is provided at the rear end of the guide rod 37 so as to be in contact with the back side of the bottom of the first receiving recess 36. When the mold is opened, the first fixed holding tool 33 moves toward the concave mold 11 by a certain distance. It is comprised so that it may protrude. The concave mold 11 is formed with a pressure receiving protrusion 39 protruding into the molding space CA at a position corresponding to the first fixed holding tool 33, a contact surface 39a is formed at the tip of the pressure receiving protrusion 39, and the first fastener 3A is used as a reference. The tip of the first fixed holder 33 is closed by fitting the concave mold 11 and the convex mold 21 with the molded body fastening member 4 positioned and held on the convex mold 21 by being fitted inside the position holding section 32. The mounting plate 7A is sandwiched between the pressure receiving projections 39, and the molded body fastening member 4 is positioned and held at an appropriate position in the thickness direction of the molding space CA.

  As shown in FIG. 8, the reference position holding part 32 is preferably configured to fit into the first fastener 3 </ b> A without a substantial gap, but from the viewpoint of manufacturing accuracy of the first fastener 3 </ b> A, You may comprise so that the clearance gap of about 0.5 mm may be formed with respect to 1 fastener 3A.

  As shown in FIG. 5 (b), the second fixing and holding means 40 is the second provided at the lower right of the convex mold 21 (position corresponding to the second fastener 3 </ b> B) toward the mating surface of the convex mold 21. 40 A of fixed holding means, the 2nd fixed holding means 40B provided in the lower left part and right part of the convex mold 21, and the center part of the left direction of the convex mold 21 (corresponding to the 3rd fastener 3C). Second fixing and holding means 40C provided at the position). However, the number and arrangement positions of the second fixed holding means 40 can be arbitrarily set according to the configuration of the molded body 1 with a fastener to be manufactured. In the present specification, the second fixing and holding means 40A, 40B, and 40C may be collectively referred to as the second fixing and holding means 40.

  As shown in FIG. 5, the second fixing and holding means 40 </ b> A for fixing and holding the second fastener 3 </ b> B is formed on the concave mold 11 and the convex mold 21 corresponding to the second fastener 3 </ b> B below the first fixed holding means 31. FIG. 9A shows the first fixed holding means 31 provided in place of the first fixed holding means 33 provided with the reference position holding portion 32 that fits in the first fastener 3A without a gap in the first fixed holding means 31. As described above, the first fixing is performed except that the second fixing holder 42A provided with the first displacement absorption holding portion 41A that is fitted and held in the second fastener 3B with a gap C so as to be relatively movable in the vertical and horizontal directions is provided. The holding unit 31 is configured similarly. For this reason, the same members as those of the first fixed holding means 31 are denoted by the same reference numerals, and the description thereof is omitted.

  In the second fixed holding means 40A, as shown in FIG. 4, the second fixed holding tool 42A is constantly urged toward the concave mold 11 by the first urging means 34, and the second fastener is placed on the first displacement absorbing portion 41A. When 3B is mounted and the concave mold 11 and the convex mold 21 are closed, the first urging force is applied between the front end portion of the second fixed holding tool 42A and the contact surface 39a of the front end portion of the pressure receiving projection 39 facing it. The attachment plate 7B is clamped by the means 34, and the second fastener 3B is fixed and held so as to be movable relative to the concave mold 11 and the convex mold 21 by a gap C.

  As shown in FIG. 7, the second fixed holding means 40B provided on the lower left part and the right part on the lower side of the convex mold 11 is a second displacement absorbing member comprising a linear groove-like concave part extending in the vertical direction on the front end surface. A block-shaped second fixed holding tool 42B having a holding part 41B, a magnet 45 embedded in the second fixed holding tool so as to be exposed on the inner surface of the second displacement absorption holding part 41B, and the second fixed holding tool 42B are recessed. 11, and a contact surface 50 a provided on the concave mold 11 that can contact the tip of the second fixing holder 42 </ b> B, and is provided in the thickness direction of the molding space CA. The anchor member 2 is configured to be held at an appropriate position so as to be relatively movable by a gap C in the left-right direction with respect to the second displacement absorption holding portion 41B.

  The second urging means 46 will be described. As shown in FIGS. 4, 6, 7, and 9 (b), a bracket 47 that protrudes downward is provided on the lower surface of the convex mold 21. A guide rod 48 is mounted so as to be movable in the mold opening and closing direction, a second fixing holder 42B is fixed to the tip of the guide rod 48 on the concave mold 11 side, and a stopper capable of contacting the bracket 47 at the rear end. 48a is fixed, and a spring member 49 made of a compression coil spring is externally mounted on the guide rod 48 between the second fixed holder 42B and the bracket 47, and the second fixed holder 42B is recessed 11 by a certain distance when the mold is opened. It is comprised so that it may protrude to the side. At the position corresponding to the second fixed holder 42B, the concave mold 11 is formed with a second accommodating recess 50 capable of accommodating the second fixed holder 42B with the molding space CA side opened, and the molded body fastening member 4 is formed into the concave mold 11. In the state where the concave mold 11 and the convex mold 21 are closed, the anchor material 2 is held by the contact surface 50a of the second housing concave portion 50, as shown in FIG. The second fixed holding tool 42B is pushed by the contact surface 50a, the second fixed holding tool 42B descends against the biasing force of the spring member 49, and the anchor material 2 is positioned at an appropriate position in the thickness direction of the molding space CA. Is fixed and held so that it can be moved relative to the left and right by the gap C.

  As shown in FIG. 9C, the second fixed holding means 40C for fixing and holding the third fastener 3C is provided on the second fixed holding tool 42B having the second displacement absorption holding part 41B composed of a groove extending in the vertical direction. Instead, a third fixed holding tool 42C having a third displacement absorbing and holding part 41C made of a U-shaped recess that fits with a gap C vertically and horizontally is provided on the third fastener 3C, and the third displacement absorbing and holding part is provided. Except for embedding the two magnets 51 so as to be exposed in the portion 41C, it is configured in the same manner as the second fixing and holding means 40B. Therefore, the description is omitted.

  The gap C is preferably 0.5 mm or greater and 3.0 mm or less. If the gap C is less than 0.5 mm, the anchor member 2 or the fastener 3 tends to be deformed because it cannot be fixed at a predetermined location due to variations in manufacturing accuracy of the molded body fastening member 4. If the gap C exceeds 3.0 mm, beads are leaked from the gap C, and burrs are generated in the foam.

  Note that the first urging means 34 and the second urging means 46 are omitted, and the first fixing holder 33 and the second fixing holders 42A, 42B, and 42C are fixed to the convex mold 21 and contacted respectively. The contact surfaces 39a and 50a are configured as separate members from the concave mold 11 so as to be movable in the mold opening / closing direction with respect to the concave mold 11, and a biasing means for biasing the contact surfaces 39a and 50a toward the convex mold 21 is provided. Is also possible.

(In-mold foam molding method)
When the molded body 1 with a fastener is manufactured using this mold apparatus M, first, the reference position holding portion 32 of the first fixed holding tool 33 is moved to the reference position holding portion 32 with the concave mold 11 and the convex mold 21 being opened. The first fastener 3A is positioned and fitted, the second fastener 3B is fitted to the second displacement absorbing holder 41A of the second fixed holder 42A, and the second displacement absorbing holder 41B of the second fixed holder 42B is fitted. The anchor material 2 is fitted and attracted and held by the magnet 45, and the third fastener 3C is fitted to the second displacement absorbing and holding portion 41C of the second fixed holder 42C and attracted and held by the magnet 51. The body fastening member 4 is fixed and held on the convex mold 21. As described above, the first fixing holder 33 fixes the first fastener 3A of the molded body fastening member 4 to the reference position holding portion 32 so as not to move relative thereto. Since the molded article fastener 3 can be relatively moved by the gap C in the absorption holding portions 41A, 41B, 41C, even if there is a dimensional variation in the molded body fastening member 4, the dimensional variation can be absorbed by the gap C. For this reason, the molded body fastening member 4 can be assembled to the convex mold 21 without applying an excessive force to the molded body fastening member 4.

  Next, the convex mold 21 and the concave mold 11 are closed. At this time, the molded body fastening member 4 is positioned and clamped between the distal end portion of the first fixing holder 33 and the contact surface 39a, and the second fixing is performed. The molded body fastening member 4 is sandwiched between the distal end portion of the holder 42A and the contact surface 39a, and between the distal end portions of the second fixed holders 42B and 42C and the contact surface 50a of the concave mold 11, and the second fixed holder 42A, In 42B and 42C, the molded body fastening member 4 is held in an appropriate position in the thickness direction of the molding space CA in a state where the molded body fastening member 4 is slidably held by the gap C in a direction perpendicular to the mold opening / closing direction. Will be.

  In this state, the polyolefin resin pre-expanded beads are filled into the molding space CA. For example, steam is heated in the concave chamber 16 and the convex chamber 26 alternately with steam of about 0.10 to 0.40 MPa (G). The foamed molded body 5 is molded by supplying the foamed foam for about 3 to 60 seconds under pressure, and heating and foaming the pre-expanded beads. At this time, the concave mold 11 and the convex mold 21 are made of an aluminum alloy or the like as described above, whereas the anchor material 2 of the molded body fastening member 4 is made of iron or stainless steel and has a linear expansion coefficient. Therefore, a displacement for deforming the molded body fastening member 4 occurs between the concave mold 11 and the convex mold 21 and the molded body fastening member 4, and this displacement is generated in the second fixed holder 42. Is absorbed by the relative movement through the gap C.

  Thus, after pre-expanded beads are heated and foamed and fused, cooling water is sprayed from the back side to the concave mold 11 and the convex mold 21 to cool the molded product, and then the concave mold 11 and the convex mold 21 are opened. Thus, a molded body 1 with a fastener is obtained.

  Thus, when attaching the molded body fastening member 4 to the convex mold 21 or in-mold foam molding in which the pre-foamed beads are heated and foamed and fused, a force to deform the molded body fastening member 4 acts. Therefore, the foam molded body 5 is integrally formed with the molded body fastening member 4 in the natural state, and the molded body fastening member 4 tries to return to the original shape after the molded body 1 with a fastener is molded. The force to do is almost completely eliminated, and the deformation of the molded body 1 with a fastener after molding can be prevented.

  In addition, if the metal mold | die which concerns on this invention is formed by integrally molding the molded object fastening member 4 in the foaming molded object 5, in addition to the vehicle seat core material, the bumper core material for vehicles and the headrest core material are used. The present invention can also be adopted when manufacturing a molded body with a fastener having an arbitrary configuration such as an automobile interior member.

(Evaluation test)
Next, although an example of the present invention explains in detail, the present invention is not limited to the following examples.

In the examples and comparative examples, the beads used are as follows.
-Polypropylene resin pre-expanded beads: Eperan-PP 36 times (manufactured by Kaneka Corporation) foamed ethylene-propylene random copolymer resin at a 36 times expansion ratio.

Evaluation in Examples and Comparative Examples was performed as follows.
<War amount>
The polyolefin resin foam obtained by in-mold foam molding was allowed to stand in an outside air environment for 1 hour. Then, after curing for 16 hours in a curing room at 75 ° C., it was allowed to stand for 24 hours or more in an outside air environment. This foam was placed on a horizontal base and measured how much it floated from the surface of the base, that is, how much warpage occurred using a gap gauge.
(Example)

[Wire fixing in mold for in-mold foam molding]
As shown in FIG. 1 and FIG. 2, an anchor material made of iron, a square wire having a diameter of 5 mm, a length of 450 mm and a width of 400 mm was fixed to a fixed holder in the mold for in-mold foam molding. Specifically, as shown in FIG. 5, the upper right U-shaped hook is positioned toward the convex mating surface and fixed to the first fixing holder without a gap, and the other U-shaped hook and anchor material are It fixed using the 2nd fixing holder whose clearance gap is 2.5 mm.

[Production of polyolefin resin foam]
After fixing the molded product fastening member to the first fixed holding tool and the second fixed holding tool, pre-expanded beads with an internal pressure of about 0.1 MPa (G) impregnated with pressurized air in a pressure-resistant container, P300 A U-shaped flat plate mold having a length of 450 mm × width of 450 mm × thickness of 50 mm shown in FIGS. 4 to 6 mounted on a molding machine (manufactured by Toyo Machine Metal Co., Ltd.) was filled. Thereafter, the pressure was increased to a water vapor pressure of 0.33 MPa (G) over 23 seconds, heated as it was for 2 seconds, the pre-expanded beads were fused together, water-cooled for 110 seconds, and then taken out from the mold. A molded body with a fastener as shown was obtained. The amount of warping is shown in Table 1.

(Comparative example)
A molded body with a fastener was produced by the same operation as in the example except that the gap C in the second fixed holder was changed to 0 mm. The amount of warping is shown in Table 1.

  The product standard for automobiles having the same size as the examples and comparative examples manufactured using the same pre-expanded beads as the examples and comparative examples is usually ± 2.0 mm. As shown in Table 1, by providing the gap C in the second fixed holder, the amount of warping can be remarkably suppressed.

  In this way, the first fixed holder is used to fix and hold the first fastener in a relatively immovable manner, and the second fixed holder is used to fix and hold a plurality of parts of the molded product fastener so that the relative movement is possible. Clearly, it can be effectively suppressed.

1: Molded body 2 with fastener: Anchor material 2a: Upper anchor 2b: Side anchor 2c: Side anchor 2d: Lower anchor 3: Fastener 3A: Fastener 3B: Fastener 3C: Fastener 4: Molded body fastening Member 5: Foam molded body 6: Molded body 7: Mounting plate 7A: Mounting plate 7B: Mounting plate 7C: Mounting plate 10: Recessed unit 11: Recessed mold 11a: Vent 12: Recessed housing 13: Recessed frame 14: Center plate 15 : Concave back plate 16: Concave chamber 17: Filler 18 a: Steam supply pipe 18 b: Cooling water supply pipe 18 c: Drain pipe 18 d: Nozzles 19 a to 19 c: Control valve 20: Convex unit 21: Convex part 21 a: Vent hole 22 : Convex housing 23: Convex frame 24: Center plate 25: Convex back plate 26: Convex chamber 28 a: Steam supply pipe 28 b: Cooling water supply pipe 28 c: Drain 28d: nozzles 29a to 29c: control valve 30: fixed holding means 31: first fixed holding means 32: reference position holding part 33: first fixed holding tool 34: first biasing means 36: first receiving recess 37: guide Rod 37a: Stopper 38: Spring member 39: Pressure receiving protrusion 39a: Contact surface 40: Second fixed holding means 40A: Second fixed holding means 40B: Second fixed holding means 40C: Second fixed holding means 41A: Second displacement Absorption holder 41B: second displacement absorption holder 41C: second displacement absorption holder 42: second fixed holder 42A: second fixed holder 42B: second fixed holder 42C: second fixed holder 45: magnet 46: second urging means 47: bracket 48: guide rod 48a: stopper 49: spring member 50: second accommodating recess 50a: abutting surface 51: magnet C: gap CA: molding space M: mold device

Claims (8)

A molded body with a fastener comprising: an anchor material; a molded body fastening member having a plurality of fasteners attached to the anchor material; and a foamed molded body using polyolefin resin pre-foamed beads. In a mold that is integrally molded by in-mold foam molding so that at least a part is embedded in the foam molded body and at least a part of the fastener is exposed to the outside from the foam molded body,
As a plurality of fixing holders that fix and hold the molded body fastening member with respect to the mold, a first fixed holding tool having a reference position holding portion that holds the fastener so as not to be relatively movable, and the molded body fastening member setting a plurality of second fixing holder having a displacement absorbing holder for holding an appropriate location spaced from the fastener to be only the relative movement a certain distance,
As the reference position holding portion, a recess that fits into the fastener without a gap is provided.
An olefin-based resin mold for foam molding. Examples displacement absorbing holder, the compact olefin resin-mold foam molding mold according to claim 1 Symbol mounting provided with recesses to be fitted with a gap relative to the fastening member. The olefin-based resin mold for internal foam molding according to claim 2 , wherein a gap on one side between the inner surface of the concave portion as the displacement absorption holding portion and the anchor material or fastener fitted thereto is 0.5 mm or more and 3.0 mm or less. Type. The mold for foam molding in an olefin resin mold according to any one of claims 1 to 3 , wherein the anchor material is made of a metal wire. The mold for foam molding in an olefin resin mold according to any one of claims 1 to 4 , wherein the fastener comprises a U-shaped hook. The mold for foam molding in an olefin resin mold according to any one of claims 1 to 5 , wherein a magnet for attracting and holding the molded body fastening member is provided on the fixed holder. One of the molds is provided with an urging means for urging the fixed holder toward the other mold, and the other mold is in contact with the tip of the fixed holder. The olefin according to any one of claims 1 to 6 , wherein a molded body fastening member can be sandwiched between a tip portion of the fixed holder and a contact surface by forming a surface and closing the mold. Mold for foam molding in plastic molds. The mold for foam molding in an olefin resin mold according to any one of claims 1 to 7 , wherein the molded body with a fastener is a vehicle seat core.

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