JP5505792B2 - Thin resin panel and manufacturing method thereof - Google Patents

Description

    The present invention relates to a thin resin panel and a method for manufacturing the same, and more particularly, to ensure adhesion between a foam resin core material and a skin sheet and to fix a metal reinforcing plate in the thickness direction. The present invention relates to a thin resin panel and a manufacturing method thereof.

Conventionally, resin panels made of laminated plates have been used as interior materials for automobiles, other vehicles, aircraft, casings for electronic devices / precision devices, building materials, logistics / packaging materials.
As interior parts for vehicles, by attaching to various vehicle panels in the passenger compartment, it is possible to cover and cover recesses such as floor panels and deck boards, uses as partitions such as tables and tonneau boards, consoles It is used for various applications such as boxes and other casings and other seats.

Regardless of the application, the appearance of the resin panel is important, and when heavy objects are loaded according to each application, compression or bending strength is required, and no load is applied. Even in the case of use, for example, sufficient strength is required to maintain the external shape of the interior product so that vibration is transmitted to the resin panel and the interior product does not deform so as to be undulated. .
Such a resin panel has a three-layer sandwich structure having a core material and a skin material bonded and fixed to each of the upper and lower surfaces of the core material, and is made of metal or rigid from the viewpoint of ensuring rigidity, particularly bending rigidity. Reinforcing material made of resin is inserted into the core.

  Patent Document 1 discloses a vehicle deck board as such a laminated plate. The vehicle deck board includes a front surface sheet made of thermoplastic resin, a back surface sheet made of thermoplastic resin, and a foamed resin and a metal reinforcing member interposed between the two sheets. The peripheral ends of both sheets are welded together. The foamed resin and the metal reinforcing member are disposed in a sealed hollow portion formed by both sheets separately from each other.

  According to such a vehicle deck board, it is possible to increase the rigidity of the vehicle deck board by arranging the metal reinforcing member in the sealed hollow portion. Due to the fact that the resin and metal reinforcing members are separately arranged in the mold, there are the following problems when molding the vehicle deck board.

  That is, such a vehicle deck board is formed by vacuum-forming one of two thermoplastic resin sheets heated and softened by a lower mold between a pair of upper and lower molds. The foamed resin and the metal reinforcing member are disposed at predetermined positions of the other thermoplastic resin sheet, and the other thermoplastic resin sheet heated and softened is disposed on the foamed resin and the metal reinforcing member. The mold is clamped to weld the peripheral portions of the two thermoplastic resin sheets, and to weld the two thermoplastic resin sheets and the foamed resin.

At that time, it is troublesome to dispose the foamed resin and the metal reinforcing member individually at predetermined positions of one of the molded thermoplastic resin sheets, particularly the front side sheet and the back side after molding. It is necessary to set an appropriate clearance between the foamed resin and the metal reinforcing member in consideration of the movement of the foamed resin welded to both sheets due to the molding shrinkage of the side sheets. The positioning of each metal reinforcing member is more difficult.
Here, molding shrinkage refers to a phenomenon in which the volume shrinks when the molten resin filled in the cavity of the mold is cooled and solidified. The type of molding material, the surface temperature of the cavity, the meat of the molded product It is affected by thickness.
In this regard, Patent Document 2 discloses a resin panel that solves such technical problems.

  This resin panel is composed of a front wall, a back wall, and a peripheral wall connecting the front wall and the back wall, and has a hollow double wall structure having a hollow portion therein, and a foam is embedded in the hollow portion. A plurality of metal rod-shaped reinforcing members, which are welded to the inner wall surfaces of the front wall and the back wall, are respectively held in the accommodating portions of the elongated through holes provided in the foam, approximately parallel to each other at an appropriate interval. ing. The rod-shaped reinforcing material is supported by the side surface of the foam constituting the housing portion.

  According to such a resin panel, it is possible to easily place it in a mold with a rod-shaped reinforcing body inserted in the foam accommodating portion during molding, while the front wall after molding and Regarding the movement of the foam accompanying the molding shrinkage of the back wall, the foam interposed between each end of the rod-shaped reinforcing body and the peripheral wall functions as an absorption allowance for molding shrinkage.

In such a resin panel, when the area of the flat portion of the panel is large with respect to the thickness of the panel and the panel is made of a thin plate, a plurality of reinforcing materials are substantially parallel to each other along the long side of the thin plate. In this case, the direction of the rigidity of the resin panel is generated and the rigidity can be improved in the extending direction of the rod-shaped reinforcing material. Improvement cannot be achieved.
However, it is possible to prevent the direction of the rigidity of the resin panel by, for example, arranging a single grid-shaped reinforcing material on the core material, but in order to insert such a reinforcing material. In addition, it is necessary to provide a grid-shaped accommodation portion in the core material, which causes a reduction in the overall manufacturing efficiency.
Therefore, in the case of such a thin resin panel, it is assumed that a metal reinforcing plate is inserted instead of inserting a plurality of rod-shaped reinforcing materials from the viewpoint of efficiently ensuring rigidity.
However, unlike the case of inserting a conventional bar-shaped reinforcing material, the following technical problems are caused.
First, when the metal reinforcing plate is simply held in the foam housing portion, the metal reinforcing plate, particularly the fixing in the thickness direction, becomes insufficient, and rattling occurs in the foam. Is a point.

More specifically, in the case of a conventional rod-shaped reinforcing material, an elongated through hole slightly smaller than the reinforcing material is provided in the foam, and the side surface of the reinforcing material is pressed against the side surface constituting the elongated through hole. However, in the case of a reinforcing plate, since the area of the flat portion is larger than the thickness, support from the side surface is insufficient, and support from the thickness direction is necessary. .
Secondly, the area of fusion of the skin material to the foam becomes insufficient, and the aesthetics such as peeling of the skin material from the foam with the passage of time are impaired.
More specifically, in the surface of the foam, the fusion area with the foam of the skin material is lost as much as the opening area of the housing portion. In the case of holding a thin plate-like reinforcing plate having a large area, it is insufficient to secure such a fusion area.
Thirdly, due to holding the reinforcing plate in the foam, a molding failure is caused when the thin resin panel is molded.

  More specifically, if the thermoplastic resin sheet is to be reheated, good adhesion between the foamed resin and the thermoplastic resin sheet constituting the back surface or front surface sheet can be achieved by external heating. As an alternative, as disclosed in Patent Document 2, when molding using a melted parison made of thermoplastic resin as disclosed in Patent Document 2, such a parison is suspended vertically downward. Then, when the foam with the metal reinforcing plate inserted between the two molds in the melted parison is placed between the molds, the back side or the front side sheet after molding is molded. As the foam welded to these sheets moves with the shrinkage, the metal reinforcing plate and the side surface of the foam constituting the housing portion are arranged in a radial direction substantially perpendicular to the thickness direction of the thin resin panel. Predetermined clearance It is necessary to set.

In that case, it is difficult to position the metal reinforcing plate vertically in the housing part with a clearance in the radial direction with respect to the housing part. By molding shrinkage of the front side sheet, the side surface of the foam constituting the housing portion hits a metal reinforcing plate that does not shrink, and in some cases, the metal reinforcing plate deforms or penetrates the side surface of the foam, and molding Cause defects.
JP2008-247003 JP 2006-334801 A

  In view of the above technical problems, the object of the present invention is to make a resin sheet made of a thin plate resin that can secure the adhesiveness between the foamed resin core material sheet and the skin material sheet and can fix the metal reinforcing plate in the thickness direction. It is in providing a panel and its manufacturing method.

In order to achieve the above object, the thin resin panel of the present invention is
A plurality of foamed resin core materials that form an internal holding space by combining inner surfaces, a skin sheet adhered to the entire outer surface of each of the plurality of foamed resin core materials, and held in the internal holding space A metal reinforcing plate,
One of the plurality of foamed resin core materials has a convex portion on the inner surface, and the other of the plurality of foamed resin core materials has a concave portion complementary to the convex portion on the inner surface, When the convex portion is fitted into the concave portion, the metal reinforcing plate is sandwiched between the plurality of foamed resin core materials and fixed in the thickness direction.

According to the thin resin panel having the above-described configuration, by adopting a plurality of foamed resin cores having a metal reinforcing plate therein, rigidity, in particular bending rigidity, is uniform throughout the panel while being thin. It is possible to improve.

At that time, by holding the metal reinforcing plate in the gap between the foamed resin core materials formed inside by abutting the inner surfaces of the plurality of foamed resin core materials, the outer surface of the metal reinforcing plate It is possible to ensure the adhesion between the foamed resin core material and the skin material sheet without causing a situation where the melted area between the foamed resin core material and the corresponding skin material sheet is reduced. On the other hand, a thin plate between the metal reinforcing plate and the skin material sheet can be obtained by fitting a plurality of foamed resin core materials together and sandwiching the metal reinforcing plate with the plurality of foamed resin core materials At the part of the foamed resin core material that exists in the thickness direction of the resin panel, using the repulsive force generated in the foamed resin, the metal reinforcing plate is fixed in the thickness direction, and the gap between the foamed resin core materials is It is possible to prevent the occurrence of rattling That.

Furthermore, a concave portion is formed on one inner surface of the foamed resin core material, and the other inner surface of the foamed resin core material is planar, and the other surface of the foamed resin core material is the other surface. The inner holding space may be formed by the inner surface closing the recess.
Furthermore, a recess is formed in the other inner surface of the foamed resin core material, and one inner surface of the foamed resin core material is planar, and one of the foamed resin core materials It is preferable that the inner holding space is formed by closing the concave portion by the inner surface.
In addition, a recess is formed on the inner surface of each of the plurality of foamed resin cores, and the internal holding space is preferably formed by abutting the openings of both the recesses.
Further, the convex portion is made of a protrusion, and the top surface of the protrusion extends to the inner surface of the skin sheet fixed to the outer surface of the other foamed resin core material, and the top surface is the inner surface. It should be welded to the surface.
Furthermore, it is preferable that the protrusion extends in the internal holding space, and the metal reinforcing plate is provided with a through hole through which the protrusion passes.
In addition, it is preferable that a curved edge is formed on one side of each of the peripheral portions of the two skin material sheets, and end peripheral surfaces of the edges are abutted to form a peripheral wall.
Further, the metal reinforcing plate is provided with a screw hole extending in the thickness direction, and the thin resin panel is preferably fixed as an accessory using the screw hole.
Furthermore, a plurality of the screw holes may be provided in alignment with the metal reinforcing plate along the direction of the long side of the thin resin panel.

In order to achieve the above object, the method for producing a thin resin panel of the present invention comprises:
One is a step of pre-forming two foamed resin cores having a convex portion on the inner surface and the other having a concave portion complementary to the convex portion on the inner surface, and preparing a metal reinforcing plate When,

While holding the metal reinforcing plate in the internal holding space formed by abutting the inner surfaces of the foamed resin core material, the convex part of one foamed resin core material is the same as that of the other foamed resin core material. Interposing the metal reinforcing plate between the two foamed resin cores by fitting them into the recesses, and integrating the two foamed resin cores and the metal reinforcing plate as an interior body;
Placing two molten thermoplastic resin sheets between the split molds;
Forming a sealed space between each of the two thermoplastic resin sheets and the corresponding split mold cavity;
A step of pressing the corresponding thermoplastic resin sheet against the corresponding cavity by sucking the air in each sealed space from the corresponding split mold side, and shaping the thermoplastic resin sheet; and
Holding the interior body by pressing the interior body against one thermoplastic resin sheet;
By clamping the split mold, the peripheral portions of the two thermoplastic resin sheets are welded together, and the inner body is welded to each of the two thermoplastic resin sheets. It has the composition to have.
Further, the step of holding the metal reinforcing plate in the internal holding space includes a foamed resin core material that constitutes the peripheral edge of the metal reinforcing plate and the internal holding space in a radial direction substantially perpendicular to the thickness direction of the thin resin panel. And providing a clearance between
The step of disposing the two melted thermoplastic resin sheets supplies the two melted thermoplastic resin sheets vertically downwardly, and the cavities are provided along the vertical direction. Having a stage of placing between the split molds;
The step of arranging the interior body may include a step of positioning the metal reinforcing plate in the internal holding space in the vertical direction while holding the clearance by fixing the metal reinforcing plate in the thickness direction.

According to the method for manufacturing a thin resin panel having the above configuration, in the thickness direction of the thin resin panel, utilizing the fact that the molding shrinkage of the thermoplastic resin sheet is significantly smaller than the vertical direction, A direction in which the metal reinforcing plate is sandwiched in the thickness direction by using the repulsive force of the foamed resin by two foamed resin cores, and the metal reinforcing plate is fixed in the thickness direction, thereby being substantially orthogonal to the thickness direction. In the radial direction, the metal reinforcing plate is not rattled in the internal holding space while providing a predetermined clearance between the peripheral edge of the metal reinforcing plate and the side surface of the foam constituting the internal holding space. It is possible to position, and thereby it is possible to manufacture a thin resin panel without causing molding defects while ensuring good adhesion between the skin material sheet and the core material sheet.

Further, in the step of forming the sealed space, the outer frame member that is movably fitted toward the molten thermoplastic resin sheet with respect to the peripheral portion of the mold is brought into contact with the thermoplastic resin sheet, A sealed space is preferably formed by the cavity of the mold, the inner peripheral surface of the outer frame member, and the surface of the thermoplastic resin sheet facing the cavity.
Furthermore, the holding step of the interior body may also serve as welding of the interior body to the one thermoplastic resin sheet.

An embodiment of a thin resin panel 100 according to the present invention will be described in detail below with reference to the drawings.
As shown in FIG. 1 and FIG. 2 (A), the thin resin panel 100 includes two foamed resin core sheets 122 (foamed resin cores) that form a sealed hollow portion 121 by joining the inner surfaces 120 together. Material sheet 122A and foamed resin core material sheet 122B), and skin material sheet 124 (upper surface side skin material sheet 124A and lower surface side skin) fused to the entire outer surface 123 of each of the two foamed resin core material sheets 122. Material sheet 124 </ b> B) and a metal reinforcing plate 125 held in the sealed hollow portion 121.

The peripheral edge of each of the two skin material sheets 124 is formed with a curved edge 127 on one side, and the end peripheral surfaces 128 of the edge 127 are butted together to form a peripheral wall 129. One 122B of the two foamed resin core material sheets 122 has a convex portion 130 on the inner surface 120, and the other 122A of the two foamed resin core material sheets 122 has a convex portion 130 on the inner surface 120. A complementary recess 131 is provided, and the protrusion 130 is fitted into the recess 131, whereby the metal reinforcing plate 125 is sandwiched between the two foamed resin core sheets 122 and fixed in the thickness direction. The protrusion 130 is made of a protrusion, and the top surface 133 of the protrusion extends to the inner surface of the skin material sheet 124A fixed to the outer surface 123 of the other foamed resin core material sheet 122A, and the top surface 133 is the inner surface. Welded to the surface.

  As shown in FIG. 2A, a recess 139 is formed on the inner surface 120 of each of the two foamed resin core sheets 122, and the sealed hollow portion 121 is formed by abutting the openings of both the recesses 139. And a metal reinforcing plate 125 is disposed in the sealed hollow portion 121. The shape of the sealed hollow portion 121 may be determined according to the shape of the metal reinforcing plate 125, but as will be described later, the foamed resin core that forms the sealed hollow portion 121 and the peripheral side surface of the metal reinforcing plate 125. A predetermined clearance is provided between the peripheral side surfaces of the material sheets. The size of the clearance is such that when the thin resin resin panel 100 is manufactured by integral molding, the skin material sheet 124 is molded and contracted, and the foamed resin core material sheet 122 welded to the skin material sheet 124 is hermetically sealed. Even when the portion 121 is forcibly deformed in the direction of reducing the size, the peripheral side surface of the metal reinforcing plate 125 hits the peripheral side surface of the foamed resin core material sheet 122 constituting the sealed hollow portion 121, and no deformation or the like occurs. It may be determined from the viewpoint.

The foamed resin core material sheet 122 may be made of a thermoplastic resin such as polyolefin resin, polystyrene, polycarbonate, or ABS resin, or a mixture thereof, or a thermosetting resin such as phenol resin, melamine resin, epoxy resin, or polyurethane. it can. The expansion ratio or the thickness of each of the foamed resin core sheets 122A and B is determined by utilizing the repulsive force of the foamed resin when the metal reinforcing plate 125 is sandwiched between the two foam resin core sheets 122A and B. It may be determined from the viewpoint of fixing the metal reinforcing plate 125 in the thickness direction of the thin resin panel 100. For example, the expansion ratio is around 15 times and the thickness is 5 mm.
As the foaming agent, any of physical foaming agents, chemical foaming agents and mixtures thereof may be used. As physical foaming agents, inorganic physical foaming agents such as air, carbon dioxide, nitrogen gas, and water, and organic physical foaming agents such as butane, pentane, hexane, dichloromethane, dichloroethane, and their supercritical fluids are used. be able to.

On the other hand, the material of the upper surface side skin material sheet 124A and the lower surface side skin material sheet 124B is a sheet formed from polypropylene, engineering plastics, olefin resin, or the like. More specifically, as will be described later, from the viewpoint of manufacturing the thin resin panel 100 by integral molding, the upper surface side skin material sheet 124A and the lower surface side skin material sheet 124B are each made of a molten thermoplastic resin sheet P1. The sheet P1 and P2 made of thermoplastic resin are made of a resin material having a high melt tension from the viewpoint of preventing variation in thickness due to drawdown, neck-in, etc. On the other hand, it is preferable to use a resin material having high fluidity in order to improve transferability to the mold and followability.

More specifically, it is a polyolefin (for example, polypropylene, high density polyethylene) which is a homopolymer or copolymer of an olefin such as ethylene, propylene, butene, isoprene pentene, methyl pentene, etc., and has an MFR (JIS) at 230 ° C. According to K-7210, measured at a test temperature of 230 ° C. and a test load of 2.16 kg) of 3.0 g / 10 min or less, more preferably 0.3 to 1.5 g / 10 min, or acrylonitrile butadiene Amorphous resin such as styrene copolymer, polystyrene, high impact polystyrene (HIPS resin), acrylonitrile / styrene copolymer (AS resin), MFR at 200 ° C. (test temperature 200 according to JIS K-7210) ℃, measured at a test load of 2.16 kg) is 3.0 to 60 g / 10 min More preferably, the melt tension at 30 to 50 g / 10 min and at 230 ° C. (using a melt tension tester manufactured by Toyo Seiki Seisakusho Co., Ltd., preheating temperature 230 ° C., extrusion speed 5.7 mm / min, diameter 2.095 mm, A strand is extruded from an orifice with a length of 8 mm, and the tension when the strand is wound around a roller with a diameter of 50 mm at a winding speed of 100 rpm is 50 mN or more, preferably 120 mN or more.

Further, in order to prevent the thermoplastic resin sheets P1 and P2 from being cracked by impact, it is preferable that a hydrogenated styrene thermoplastic elastomer is added in an amount of less than 30 wt%, preferably less than 15 wt%. . Specifically, a styrene-ethylene / butylene-styrene block copolymer, a styrene-ethylene / propylene-styrene block copolymer, a hydrogenated styrene-butadiene rubber and a mixture thereof are suitable as the hydrogenated styrene-based thermoplastic elastomer. The styrene content is less than 30 wt%, preferably less than 20 wt%, and the MFR at 230 ° C. (measured at a test temperature of 230 ° C. and a test load of 2.16 kg according to JIS K-7210) is 1.0 to 10 g / 10. Minute, preferably 5.0 g / 10 min or less and 1.0 g / 10 min or more.

Furthermore, the thermoplastic resin sheets P1 and P2 may contain an additive. Examples of the additive include inorganic fillers such as silica, mica, talc, calcium carbonate, glass fiber, and carbon fiber, and plasticizer. , Stabilizers, colorants, antistatic agents, flame retardants, foaming agents and the like. Specifically, silica, mica, glass fiber or the like is added in an amount of 50 wt% or less, preferably 30 to 40 wt%, based on the molding resin.
The metal reinforcing plate 125 may be any metal as long as it is a metal having higher rigidity than the foamed resin core material sheet 122, and may be made of steel. The thickness and area of the metal reinforcing plate 125 may be appropriately determined from the viewpoints of rigidity required for the thin resin panel 100, particularly bending rigidity, and weight allowed for the thin resin panel 100.

Further, the metal reinforcing plate 125 is provided with a screw hole 135 extending in the thickness direction, and the thin resin panel 100 is fixed as an accessory using the screw hole 135. As will be described later with reference to FIG. 8, when fixing the thin resin panel 100 to the main body as an attached table, a screw hole for fixing the metal reinforcing plate 125 according to the width of the thin resin panel 100. In this case, a plurality of screw holes 135 may be provided in alignment with the metal reinforcing plate 125 along the direction of the long side of the thin resin panel 100. Therefore, it is necessary to secure the area of the metal reinforcing plate 125.

As a modification, as shown in FIG. 2B, a recess 139B is formed on the inner surface 120B of the foamed resin core material sheet 122B, and the inner surface 120A of the foamed resin core material sheet 122A is planar. Yes, the sealed hollow portion 121 may be formed by the inner surface 120A of the foamed resin core material sheet 122A closing the recess 139B. Alternatively, a recess 139A is formed on the inner surface 120A of the foamed resin core material sheet 122A, and the inner surface 120B of the foamed resin core material sheet 122B is planar, and the inner surface of the foamed resin core material sheet 122B. The sealed hollow portion 121 may be formed by 120B closing the recess 139A.
As a further modification, as shown in FIG. 2 (C), it is the same as that in FIG. 2 (A) that the recessed portions 139 are provided in the foamed resin core material sheets 122A and 122B. The metal reinforcing plate 125 may be provided with a through hole 143 through which the protrusion passes, extending through the sealed hollow portion 121.
Next, a method for manufacturing the thin resin panel 100 according to the present embodiment will be described in detail below. First, an apparatus for manufacturing the thin resin panel 100 will be described below.

As shown in FIG. 3, the molding device 10 of the thin resin panel 100 includes an extrusion device 12 and a mold clamping device 14 disposed below the extrusion device 12, and is in a molten state extruded from the extrusion device 12. The thermoplastic resin sheet P is sent to the mold clamping device 14, and the molten thermoplastic resin sheet P is molded by the mold clamping device 14, thereby making the skin material sheet 124. Here, since the apparatuses for extruding each of the two thermoplastic resins and sending them to the mold clamping device 14 are the same, only one of them will be described, and the other will be given the same reference number for the description. Omitted.

The extruding device 12 is a conventionally known type, and a detailed description thereof is omitted. However, a cylinder 18 provided with a hopper 16, a screw (not shown) provided in the cylinder 18, and a screw are connected to the screw 18. The hydraulic motor 20, an accumulator 22 that communicates with the inside of the cylinder 18, and a plunger 24 provided in the accumulator 22, and a resin pellet introduced from the hopper 16 is screwed into the cylinder 18 by the hydraulic motor 20. The molten resin is melted and kneaded by the rotation of the resin, and the molten resin is transferred to the accumulator chamber 22 and stored in a certain amount. The plunger 24 is driven to feed the molten resin toward the T-die 28, A pair of rollers in which the plastic resin sheet P is extruded and spaced from each other 0 while clamped sent out downward by being suspended between the split mold blocks 32. Thereby, as will be described in detail later, the thermoplastic resin sheet P is disposed between the split molds 32 in a state of having a uniform thickness in the vertical direction (extrusion direction).

The extrusion capability of the extrusion device 12 is appropriately selected from the viewpoint of the size of the resin molded product to be molded, the draw-down of the thermoplastic resin sheet P, or the prevention of neck-in occurrence. More specifically, from a practical point of view, the extrusion amount of one shot in intermittent extrusion is preferably 1 to 10 kg, and the extrusion rate of the resin from the extrusion slit 34 is several hundred kg / hour or more, more preferably 700 kg / hour or more. Further, from the viewpoint of preventing the draw-down of the thermoplastic resin sheet P or the occurrence of neck-in, the extrusion process of the thermoplastic resin sheet P is preferably as short as possible, depending on the type of resin, MFR value, and melt tension value. In general, the extrusion process should be completed within 40 seconds, more preferably within 10 to 20 seconds. For this reason, the unit area and the amount of extrusion per unit time from the extrusion slit 34 of the thermoplastic resin are 50 kg / hour cm ² or more, more preferably 150 kg / hour cm ² or more.

By feeding the thermoplastic resin sheet P sandwiched between the pair of rollers 30 by the rotation of the pair of rollers 30 downward, the thermoplastic resin sheet P can be stretched and thinned, and extruded thermoplastic. By adjusting the relationship between the extrusion speed of the resin sheet P and the feed speed of the thermoplastic resin sheet P by the pair of rollers 30, it is possible to prevent the occurrence of drawdown or neck-in. It is possible to reduce the restrictions on the type, in particular the MFR value and the melt tension value, or the extrusion rate per unit time.

As shown in FIG. 3, the extrusion slit 34 provided in the T die 28 is disposed vertically downward, and the continuous thermoplastic resin sheet P extruded from the extrusion slit 34 is suspended from the extrusion slit 34 as it is, It is sent vertically downward. The extrusion slit 34 can change the thickness of the continuous thermoplastic resin sheet P by making the interval variable.

The pair of rollers 30 will be described. In the pair of rollers 30, the rotation axes of the pair of rollers 30 are arranged substantially horizontally in parallel with each other, one is the rotation drive roller 30A, and the other is driven to rotate. The roller 30B. More specifically, as shown in FIG. 3, the pair of rollers 30 are arranged so as to be line-symmetric with respect to the thermoplastic resin sheet P extruded in a form that hangs downward from the extrusion slit 34.

The diameter of each roller and the axial length of the roller may be appropriately set according to the extrusion speed of the thermoplastic resin sheet P to be molded, the length and width of the sheet in the extrusion direction, the type of resin, and the like. As will be described later, from the viewpoint of smoothly feeding the thermoplastic resin sheet P downward by rotation of the roller with the thermoplastic resin sheet P sandwiched between the pair of rollers 30, the diameter of the rotational drive roller 30A Is preferably slightly larger than the diameter of the driven roller 30B. The diameter of the roller is preferably in the range of 50 to 300 mm, and the thermoplastic resin sheet P wraps around the roller even when the roller curvature is too large or too small in contact with the thermoplastic resin sheet P. It causes a malfunction.
On the other hand, the mold clamping device 14 is also a conventionally known type like the extrusion device 12, and detailed description thereof will be omitted, but the two divided molds 32A and 32B and the molds 32A and 32B are melted. And a mold driving device that moves between an open position and a closed position in a direction substantially perpendicular to the supply direction of the thermoplastic resin sheet P.

As shown in FIG. 3, the two divided molds 32 </ b> A and 32 </ b> B are arranged with the cavities 116 facing each other, and the cavities 116 are arranged so as to face in a substantially vertical direction. Concavities and convexities 119 are provided on the surface of each cavity 116 according to the outer shape and surface shape of a molded product formed based on the molten thermoplastic resin sheet P.

In each of the two divided molds 32A and 32B, a pinch-off part 118 is formed around the cavity 116. The pinch-off part 118 is formed in an annular shape around the cavity 116, and the opposing molds 32A and 32B are formed. Protrusively toward. As a result, when the two divided molds 32A and 32B are clamped, the tip portions of the respective pinch-off portions 118 come into contact with each other and parting around the peripheral edges of the two molten thermoplastic resin sheets P1 and P2 It welds so that line PL may be formed.

A mold 33A is slidably fitted on the outer periphery of the mold 32A so as to be slidable in a sealed state, and the mold 33A can be moved relative to the mold 32A by a mold moving device (not shown). . More specifically, the mold frame 33A can be brought into contact with the side surface of the thermoplastic resin sheet P1 disposed between the molds 32A and 32B by projecting toward the mold 32B with respect to the mold 32A. is there. Similarly, a mold 33B is provided for the mold 32B.

The mold driving device is the same as the conventional one, and the description thereof is omitted. However, the two divided molds 32A and 32B are respectively driven by the mold driving device and are divided into two in the open position. Two molten thermoplastic resin sheets P can be arranged between the molds 32A and 32B, and the pinch-off portions 118 of the two divided molds 32A and 32B come into contact with each other in the closed position. The annular pinch-off portions 118 are in contact with each other so that a sealed space is formed in the two divided molds 32A and 32B. Regarding the movement of the molds 32A and 32B from the open position to the closed position, the closed position, that is, the position where the pinch-off portions 118 abut each other is between the two continuous thermoplastic resin sheets P1 and P2 in the molten state. The molds 32A and 32B are driven at the same distance from the two thermoplastic resin sheets P1 and P2 and moved toward the positions by the mold driving device.
Note that the extrusion device and the pair of rollers for one continuous thermoplastic resin sheet P1 and the extrusion device and the pair of rollers for the other continuous thermoplastic resin sheet P2 are arranged symmetrically with respect to this closed position. Has been.

As shown in FIG. 5, a vacuum suction chamber 80 is provided inside the divided mold 32 </ b> A. The vacuum suction chamber 80 communicates with the cavity 116 </ b> A through the suction hole 82, and the suction hole 82 is opened from the vacuum suction chamber 80. By sucking through, the thermoplastic resin sheet P1 is adsorbed toward the cavity 116A and shaped into a shape along the outer surface of the cavity 116A. More specifically, the outer surface 117 of the thermoplastic resin sheet P1, which is the material of the lower skin sheet 124B, is shaped by the irregularities 119 provided on the outer surface 123 of the cavity 116A. The thermoplastic resin sheet P2 is shaped similarly.
On the other hand, a conventionally known blow pin (not shown) is applied to the divided mold 32B so that when the molds 32A and 32B are clamped, blowing pressure can be applied from within the sealed space formed by both molds. ) Is installed.
A method for manufacturing the thin resin panel 100 using the molding apparatus 10 for the thin resin panel 100 having the above configuration will be described below with reference to the drawings.
First, one of the two foam resin core material sheets 122A and 122B having a convex portion 130 on the inner surface 120 and the other having a concave portion 131 complementary to the convex portion 130 on the inner surface 120 is molded in advance. At the same time, a metal reinforcing plate 125 is prepared.

More specifically, the production of the foamed resin core material sheet 122 will be described. For example, a polyolefin resin is supplied to an extruder (not shown), kneaded while being melted by heating, and then a predetermined amount of foaming agent is added. The mixture is further kneaded in an extruder to form a foamed molten resin, and the foamed molten resin is filled into an accumulator (not shown) while maintaining a resin temperature suitable for foaming and a pressure at which the foamed molten resin does not start foaming. To do. Next, by pressing a ram (not shown) of the accumulator with the gate at the die tip of the extrusion head open, the foamed molten resin is opened to the low pressure region, and the foamed cylindrical parison P is formed. The The foamed resin core material sheet 122 can be formed by placing the cylindrical parison P between, for example, a pair of molds, clamping the pair of molds, and applying pressure from the inside. By such a method, the two foamed resin core material sheets 122A and 122B are respectively formed.
The foamed resin core material sheet 122 may be formed by a known manufacturing method using polystyrene foam beads.

Next, the metal reinforcing plate 125 is held in the sealed hollow portion 121 formed by abutting the inner surfaces of the foamed resin core material sheets 122A and 122B, and the convex portion of the one foamed resin core material sheet 122A. By fitting 130 into the recess 131 of the other foamed resin core material sheet 122B, the metal reinforcing plate 125 is sandwiched between the two foamed resin core material sheets 122A and B, and the two foamed resin core materials The sheets 122A, B and the metal reinforcing plate 125 are integrated as an interior body 140.
When the metal reinforcing plate 125 is held in the sealed hollow portion 121, the foamed resin core material that forms the peripheral edge of the metal reinforcing plate 125 and the sealed hollow portion 121 in a radial direction substantially orthogonal to the thickness direction of the thin resin panel 100. A predetermined clearance is provided between the sheet 122 and the sheet 122.
In this case, the metal reinforcing plate 125 is sandwiched in the thickness direction by using the repulsive force of the foamed resin by the two foam resin core sheets 122A and B, and the metal reinforcing plate 125 is fixed in the thickness direction. Thus, the metal reinforcing plate 125 can be positioned in the sealed hollow portion 121 without causing backlash.

  Next, in FIG. 3, a predetermined amount of the melted and kneaded thermoplastic resin is stored in the accumulator 22, and the stored thermoplastic resin is discharged from the extrusion slits 34 provided in the T die 28 at a predetermined amount per unit time. In this case, the thermoplastic resin swells and is extruded at a predetermined extrusion speed with a predetermined thickness so as to hang downward into a molten sheet.

Subsequently, the pair of rollers 30 is moved to the open position, and the gap between the pair of rollers 30 arranged below the extrusion slit 34 is expanded from the thickness of the thermoplastic resin sheet P, thereby being extruded in a molten state. The lowermost part of the thermoplastic resin sheet P is smoothly supplied between the pair of rollers 30. In addition, the timing which expands the space | interval of the rollers 30 from the thickness of the sheet | seat P made from a thermoplastic resin may be performed at the time of the completion | finish of secondary shaping | molding for every one shot not after an extrusion start.
Next, the pair of rollers 30 are moved close to each other and moved to the closed position, the interval between the pair of rollers 30 is narrowed to sandwich the thermoplastic resin sheet P, and the thermoplastic resin sheet P is moved downward by the rotation of the rollers. Send it out.
Next, as shown in FIG. 3, the thermoplastic resin sheet P having a uniform thickness in the extrusion direction is disposed between the divided molds 32 </ b> A and 32 </ b> B disposed below the pair of rollers 30. Thereby, the thermoplastic resin sheet P is positioned in a form that protrudes around the pinch-off portion 118.
The above process is performed for each of the two thermoplastic resin sheets P1 and P2, and the thermoplastic resin sheet P2 that is the material of the upper surface skin sheet 124A and the thermoplastic material that is the material of the lower surface skin sheet 124B. The resin sheet P1 is disposed between the divided molds 32A and 32B in a state of being spaced apart from each other.
In this case, the two thermoplastic resin sheets P1 and P2 are arranged between the divided molds 32A and 32B by adjusting the distance between the extrusion slits 34 or the rotational speed of the pair of rollers 30 independently of each other. It is possible to adjust the thickness when being applied.

Next, as shown in FIG. 4, the mold 33A is made of a thermoplastic resin facing the mold 32A toward the thermoplastic resin sheet P1 which is the material of the lower surface skin sheet 124B with respect to the mold 32A. The sheet P1 is moved until it hits the outer surface 117 of the sheet P1. Similarly, the mold 33B is moved until it contacts the outer surface 117 of the thermoplastic resin sheet P2.

Next, as shown in FIG. 4 and FIG. 5, the first surface constituted by the cavity 116A of the mold 32A, the inner peripheral surface 102 of the mold 33A, and the outer surface 117 of the thermoplastic resin sheet P1 facing the mold 32A. The thermoplastic resin sheet P1 is pressed against the cavity 116A by being sucked from the vacuum suction chamber 80 through the suction hole 82 through the one sealed space 84, so that the thermoplastic resin has a shape along the uneven surface of the cavity 116A. The sheet P1 is shaped. The thermoplastic resin sheet P2 is similarly sucked and shaped.
Next, as shown in FIG. 5, the preformed interior body 140 is disposed between the divided molds 32 and pressed against the thermoplastic resin sheet P1 to be welded. In this case, by fixing the metal reinforcing plate 125 in the thickness direction, the metal reinforcing plate 125 is positioned in the sealed hollow portion 121 in the vertical direction while maintaining the clearance.
The interior body 140 is adsorbed by, for example, using a known adsorption type manipulator and placing it between the split molds 32 while adsorbing and holding the side surface of the interior body 140 and welding it to the thermoplastic resin sheet P1. The type manipulator may be detached from the interior body 140 and retracted from between the split molds 32.

Next, as shown in FIG. 6, the thermoplastic resin sheets P1 and P2 are sucked and held with the molds 33A and 33B contacting the outer surfaces 117 of the thermoplastic resin sheets P1 and P2 held in their positions. However, the molds 32A and 32B are moved toward each other until the respective annular pinch-off portions 118A and B contact each other. In this case, the contact position in the mold clamping direction between the pinch-off portions 118A and 118B is between two thermoplastic resin sheets P1 and P2 that are separated from each other. As shown in FIG. By contacting B with each other, the two thermoplastic resin sheets P1 and P2 are welded and fixed to each other's peripheral edge portions 126, and the inner body 140 is arranged inside, so that the peripheral edge of the thermoplastic resin sheet is arranged. While forming the sealed peripheral wall 129, the lower surface side skin material sheet 124B and the upper surface side skin material sheet 124A are welded to the interior body 140, respectively.
Next, the thermoplastic resin sheets P1 and P2 are pressurized through the second sealed space 86 formed inside by the mold 32A and the mold 32B, and the thermoplastic resin from the mold 32A side through the first sealed space 84. The manufactured sheet P1 is continuously sucked. Similarly, the thermoplastic resin sheet P2 is sucked.
Next, as shown in FIG. 7, the split molds 32A and 32B are opened, the molded thin resin panel 100 is taken out, and the burr portions B outside the pinch-off portions 118A and B are cut and molded. Is completed.

As described above, each time the molten resin is intermittently extruded in the primary molding, the sheet-like thin resin panel 100 can be molded one after another by repeating the above-described steps. The thermoplastic resin is intermittently extruded as a melted thermoplastic resin sheet P by extrusion molding, and the thermoplastic resin sheet P extruded by secondary molding (blow molding or vacuum molding) is molded using a mold. Is possible.

  FIG. 8 shows an example of a main body of an ultrasonic diagnostic apparatus in order to use the thin resin panel 100 manufactured as described above as an attached table in a Shinkansen, an airplane seat back, an ultrasonic diagnostic apparatus, a baby seat, a wash counter, etc. The state fixed to the back surface of 134 is shown. More specifically, the vertical surface 137 of the mounting tool 136 is fixed to the back surface of the apparatus main body 134 using, for example, screws, using the mounting tool 136 having an L-shaped cross section, while the horizontal surface 138 of the mounting tool 136 is fixed to the thin resin panel 100. For example, it is fixed to the lower surface by screwing.

More specifically, by using the screw hole 135 provided in the metal reinforcing plate 125 of the thin resin panel 100, the attachment tool 136 is compared with the case where the screw hole is provided in the resin portion of the thin resin panel 100. It is possible to firmly fix the horizontal surface 138 to the lower surface of the thin resin panel 100. In particular, when the area of the flat portion of the thin resin panel 100 is large and the width of the fixture 136 is large accordingly, a plurality of screw holes 135 are formed along the long side of the thin resin panel 100 in the metal reinforcing plate 125. By arranging and arranging, the thin resin panel 100 is firmly fixed to the back surface of the apparatus main body 134 via the attachment 136, and the thin resin panel 100 is bent with the thin resin panel 100 as an attached table. It is possible to stably place fixtures and the like used for ultrasonic diagnosis on the upper surface while maintaining flatness without any problems.

According to the thin resin panel 100 having the above configuration, by adopting the plurality of foamed resin core sheets 122 having the metal reinforcing plates 125 therein, rigidity, in particular, bending rigidity is obtained while being thin. It is possible to improve the entire panel 100 uniformly.

  At that time, the metal reinforcing plate 125 is held in the gap between the foamed resin core material sheets 122 formed inside each other by abutting the inner surfaces 120 of the plurality of foamed resin core material sheets 122, so that the metal The outer surface 123 of the reinforcing plate 125 is exposed, and the foamed resin core material sheet 122 does not occur so as to reduce the fusion area between the foamed resin core material sheet 122 and the corresponding skin material sheet 124. It is possible to secure the adhesiveness between the resin sheet and the skin material sheet 124. On the other hand, the plurality of foamed resin core material sheets 122 are fitted to each other, and the metal reinforcing plate is formed by the plurality of foamed resin core material sheets 122. The portion of the foamed resin core material sheet 122 existing in the thickness direction of the thin resin resin panel 100 between the metal reinforcing plate 125 and the skin material sheet 124 by sandwiching the 125. In the above, it is possible to fix the metal reinforcing plate 125 in the thickness direction by utilizing the repulsive force generated in the foamed resin, and to prevent rattling from occurring in the gap between the foamed resin core material sheets 122. .

According to the manufacturing method of the thin resin panel 100 having the above-described configuration, the thickness shrinkage of the thermoplastic resin sheet is significantly smaller in the thickness direction of the thin resin panel 100 than in the vertical direction. Then, the metal reinforcing plate 125 is sandwiched in the thickness direction by using the repulsive force of the foamed resin by the two foamed resin core material sheets 122, and the metal reinforcing plate 125 is fixed in the thickness direction. The metal reinforcing plate 125 is sealed in a sealed hollow portion while providing a predetermined clearance between the peripheral edge of the metal reinforcing plate 125 and the side surface of the foam constituting the sealed hollow portion 121 in a radial direction substantially perpendicular to the direction. It is possible to perform positioning without causing rattling in 121, thereby causing poor molding while ensuring good adhesion between the skin material sheet 124 and the core material 122 sheet. It is possible to produce the Ku thin plastic panel 100.

The embodiments of the present invention have been described in detail above, but various modifications or changes can be made by those skilled in the art without departing from the scope of the present invention. For example, in the present embodiment, it has been described that the sealed hollow portion is formed by overlapping the foam resin core material, and the metal reinforcing plate is disposed in the sealed hollow portion, but the present invention is not limited thereto. As long as the metal reinforcing plate can be stably positioned by sandwiching it between the two foamed resin cores, the four sides of the metal reinforcing plate are not surrounded by the foamed resin core. Or all may be exposed to the outside.
Moreover, in this embodiment, although it demonstrated as a thin plate planar core material sheet as a foamed resin core material, it is not limited to it, The thing of the solid shape containing a curved surface may be sufficient.
Furthermore, in this embodiment, although it demonstrated as what employ | adopts two foaming resin core material sheets, it is not limited to it, One or both foaming resin core material sheets are employ | adopted with the division | segmentation form. More than two sheets of foamed resin core material sheet may be employed.
In addition, in the present embodiment, the case where a single metal reinforcing plate is used has been described. However, the present invention is not limited thereto, and a plurality of metal reinforcing plates are prepared according to the size of the thin resin panel. And you may arrange | position each metal reinforcement board in the corresponding hollow part formed in the foaming resin core material at intervals mutually.

It is a perspective view of the thin resin panel concerning an embodiment of the present invention. It is sectional drawing which follows the line AA of FIG. It is a figure which shows the state by which the molten resin sheet was arrange | positioned between the division molds with the shaping | molding apparatus which concerns on embodiment of this invention. It is a figure which shows the state which is making the outer frame of a division mold contact the side surface of a molten resin sheet in the shaping | molding apparatus which concerns on embodiment of this invention. It is a figure which shows the state which is shaping the molten resin sheet in the shaping | molding apparatus which concerns on embodiment of this invention. It is a figure which shows the state which clamped the division mold in the shaping | molding apparatus which concerns on embodiment of this invention. In the molding apparatus which concerns on embodiment of this invention, it is a figure which shows the state which opened the split mold. It is a figure which shows the condition which is fixing to the main body by using the thin resin panel which concerns on embodiment of this invention as an attached table.

P Thermoplastic resin sheet PL Parting line 12 Extruding device 14 Clamping device 16 Hopper 18 Cylinder 20 Hydraulic motor 22 Accumulator 24 Plunger 28 T die 30 Roller 32 Split mold 33 Mold 34 Extrusion slit 80 Vacuum suction chamber 82 Vacuum Suction hole 84 First sealed space 86 Second sealed space 100 Thin resin panel 102 Inner peripheral surface 116 Cavity 117 Outer surface 118 Pinch-off portion 119 Projection body 120 Inner surface 121 Sealed hollow portion 122 Foamed resin core material sheet 123 Outer surface 124 Skin material sheet 125 Metal reinforcing plate 126 Peripheral part 127 Edge 128 End peripheral surface 129 Peripheral wall 130 Convex part 131 Concave part 132 Opening part 133 Top surface 134 Main body 135 Screw hole 136 Attachment tool 137 Vertical surface 138 Horizontal surface 139 Concave part 140 Inner body 143 Through hole

Claims (13)

A pair of foamed resin core materials, each of which is in a single shape or a divided shape, forming an internal holding space by joining the inner surfaces together, and bonded to the entire outer surface of each of the pair of foamed resin core materials Having a skin sheet and a metal reinforcing plate held in the internal holding space;
One of the pair of foamed resin cores has a convex part on the inner surface, and the other of the pair of foamed resin cores has a concave part complementary to the convex part on the inner surface, A thin plate resin panel, wherein the metal reinforcing plate is sandwiched between the pair of foamed resin core members and fixed in the thickness direction by fitting a convex portion into the concave portion. One said surface of said pair of foamed plastic core member, a concave portion is formed, the other of said inner surface of said pair of foamed resin core is planar, the pair of resin foam core The thin resin panel according to claim 1, wherein the inner holding space is formed by the other inner surface of the material closing the concave portion. The other of said inner surface of said pair of foamed plastic core member, a concave portion is formed, while the inner surface of said pair of foamed plastic core member is a flat shape, and the pair of resin foam core The thin resin panel according to claim 1, wherein the inner holding space is formed by the inner surface of one of the materials closing the recess. 2. The thin plate resin-made product according to claim 1, wherein a concave portion is formed on the inner surface of each of the pair of foamed resin core materials, and the internal holding space is formed by abutting the openings of both concave portions. panel. The convex portion comprises a protrusion, and the top surface of the protrusion extends to the inner surface of the skin sheet fixed to the other outer surface of the pair of foamed resin cores, and the top surface is the inner surface. The thin resin panel according to any one of claims 1 to 4, which is welded to a surface.         6. The thin resin panel according to claim 5, wherein the protrusion extends through the internal holding space, and the metal reinforcing plate is provided with a through hole through which the protrusion penetrates. The edge part of each of the two skin material sheets is formed with a curved edge on one side, and end peripheral surfaces of the edge are butted together to constitute a peripheral wall. panel. One is a step of pre-forming two foamed resin cores having a convex portion on the inner surface and the other having a concave portion complementary to the convex portion on the inner surface, and preparing a metal reinforcing plate When,
While holding the metal reinforcing plate in the internal holding space formed by abutting the inner surfaces of the foamed resin core material, the convex part of one foamed resin core material is the same as that of the other foamed resin core material. Interposing the metal reinforcing plate between the two foamed resin cores by fitting them into the recesses, and integrating the two foamed resin cores and the metal reinforcing plate as an interior body;
Placing two molten thermoplastic resin sheets between the split molds;
Forming a sealed space between each of the two thermoplastic resin sheets and the corresponding split mold cavity;
A step of pressing the corresponding thermoplastic resin sheet against the corresponding cavity by sucking the air in each sealed space from the corresponding split mold side, and shaping the thermoplastic resin sheet; and
Holding the interior body by pressing the interior body against one thermoplastic resin sheet;
By clamping the split mold, the peripheral portions of the two thermoplastic resin sheets are welded together, and the inner body is welded to each of the two thermoplastic resin sheets. A method for producing a thin resin panel, comprising: The step of holding the metal reinforcing plate in the internal holding space is between the peripheral edge of the metal reinforcing plate and the foamed resin core material constituting the internal holding space in a radial direction substantially orthogonal to the thickness direction of the thin resin panel. A step of providing clearance in the
The step of disposing the two melted thermoplastic resin sheets supplies the two melted thermoplastic resin sheets vertically downwardly, and the cavities are provided along the vertical direction. Having a stage of placing between the split molds;
The arrangement step of the interior body includes a step of positioning the metal reinforcing plate in the internal holding space in a vertical direction while holding the clearance by fixing the metal reinforcing plate in the thickness direction. A method for producing a thin resin panel as described in 1. In the formation of the sealed space, an outer frame member that is movably fitted to the peripheral edge of the mold toward the molten thermoplastic resin sheet is brought into contact with the thermoplastic resin sheet, The method for producing a thin resin panel according to claim 8, wherein a sealed space is formed by the cavity, the inner peripheral surface of the outer frame member, and the surface facing the cavity of the thermoplastic resin sheet. The method for manufacturing a thin resin panel according to claim 8, wherein the holding step of the inner body also serves as welding of the inner body to the one thermoplastic resin sheet. The thin plate resin panel according to claim 1, wherein the metal reinforcing plate is provided with a screw hole extending in a thickness direction thereof, and the thin plate resin panel is fixed as an accessory using the screw hole. . The thin resin panel according to claim 12, wherein a plurality of the screw holes are provided in alignment with the metal reinforcing plate along a direction of a long side of the thin resin panel.

Images