JP6652686B1 - Handrail manufacturing method and handrail manufacturing device - Google Patents

Abstract

An object of the present invention is to provide a method for manufacturing a handrail that can form an arbitrary pattern and irregularities on the handrail surface. A method for manufacturing a handrail according to the present invention includes a step (S200) of forming a foamed resin layer 20 containing a foaming agent (21) on a surface 10a of a pipe member 10, and forming the foamed resin layer 20. The method includes a step of disposing the pipe member 1) in the mold 200 and a step of forming the uneven pattern portion 60 on the foamed resin layer 20 (S350). The mold 200 has a cavity 38 corresponding to the concave / convex pattern portion 60 formed on the surface 20 a of the foamed resin layer 20. The cavity 38 has a suction hole 39 for sucking air in the cavity. In the step of forming the concavo-convex pattern portion 60 (S350), the heating of the foamed resin layer 20 is performed while the inside of the cavity 38 is under a negative pressure. [Selection diagram] FIG.

Description

The present invention relates to a handrail manufacturing method and a handrail manufacturing apparatus. In particular, the present invention relates to a handrail manufacturing method and a handrail manufacturing apparatus capable of forming irregularities and patterns on the surface of a handrail.
This application claims priority based on Japanese Patent Application No. 2018-092146 filed on May 11, 2018, the entire contents of which application is incorporated herein by reference. ing.

  With the progress of the aging society in recent years, the necessity of installing handrails in stairs, washrooms, toilets, corridors, entrances, entrances and entrances also tends to increase in general houses (Patent Documents 1 and 2, etc.) ). In particular, handrails installed along stairs need to support a person's weight when going up and down stairs, and are required to have sufficient strength characteristics to withstand the load at that time.

  Conventionally, as a material of a handrail bar, a natural wood, a laminated wood, a woody material such as a medium density fiberboard, a metal such as aluminum and stainless steel, or a resin is used. For a handrail bar for indoor use, a wood material having a good touch and relatively high strength is generally preferred.

  However, a problem has been pointed out that a handrail bar formed of a wooden material is cut out from natural wood, laminated wood, or the like, thereby increasing the manufacturing cost. In addition, wooden handrail bars are inferior in workability and the like as compared with handrail bars made of metal that can be easily bent because it is difficult to create a complicated curved shape at a corner or the like.

  On the other hand, if a bare hand touches a metal material forming a building material or equipment for a general house, the user may feel cold and feel uncomfortable. For this reason, it is preferable that at least a portion where the human body comes into contact is a member that makes it difficult to feel the cold at the time of contact.

JP-A-2005-25343 JP-A-10-266514

  Patent Literature 1 proposes a handrail bar that not only has a warm tactile sensation like a natural tree when touched, but also has rigidity that can withstand use. Specifically, there is disclosed a handrail bar in which a foamed resin layer having a predetermined thickness, expansion ratio, and thermal conductivity is formed on the surface of a metal handrail bar body.

  Patent Document 2 proposes a handrail that prevents cold, static electricity, and slippage without attaching a cover. Specifically, there is disclosed a handrail made of a fiber reinforced plastic pipe in which steps of 10 μm to 700 μm are formed at intervals of 1 to 50 mm in the longitudinal direction of the pipe surface.

  With the handrails according to the techniques of Patent Documents 1 and 2, it is possible to form a fine step (for example, a step having a height of 700 μm or less), but it has been found that it is difficult to form an arbitrary pattern and irregularities. . More specifically, in the handrail in which the foamed resin layer is formed around the metal pipe, the inventor of the present application was unable to form the designed pattern / concavo-convex shape on the handrail surface. It had only rough surfaces (or wavy irregularities of low height) such as 2. Under such circumstances, the inventor of the present application has diligently studied and found a method of forming an arbitrary pattern and irregularities on the handrail surface with a slight opportunity, and has arrived at the present invention.

  The present invention has been made in view of the above points, and a main object of the present invention is to provide a method for manufacturing a handrail capable of forming arbitrary patterns and irregularities on the handrail surface.

  The method for manufacturing a handrail according to the present invention includes a step of forming a foamed resin layer containing a foaming agent on a surface of a pipe member, and a step of disposing the pipe member having the foamed resin layer formed thereon in a mold. Forming a concavo-convex pattern portion on the foamed resin layer. The mold has a cavity corresponding to the uneven pattern formed on the surface of the foamed resin layer. A suction hole for sucking air in the cavity is formed in the cavity. In the step of forming the concavo-convex pattern portion, heating the foamed resin layer is performed while applying a negative pressure to the inside of the cavity.

  In a preferred embodiment, in the step of forming the foamed resin layer, the foamed resin layer contains an unfoamed foaming agent. When the foamed resin layer is heated, the unfoamed foaming agent foams.

  In a preferred embodiment, the pipe member is a metal pipe. The step of forming the foamed resin layer is performed by extruding a resin material containing the foaming agent on the pipe member. In the step of forming the foamed resin layer, a coating layer is formed on an outer layer of the foamed resin layer. The uneven pattern portion is formed by changing the height of the surface of the coating layer.

  In a preferred embodiment, the mold is a metal mold provided with a heater. The mold has a separable structure. The mold has a central opening for accommodating the pipe member on which the foamed resin layer is formed. The cavity is formed on a surface where the central opening is located. A suction tube communicating with the suction hole is connected to the mold. The heating of the foamed resin layer is performed by the heater.

  In another handrail manufacturing method according to the present invention, a step of forming a foamed resin layer containing a foaming agent on the surface of a pipe member, and disposing the pipe member having the foamed resin layer formed in a mold. A step of arranging the mold on which the pipe member is arranged in a chamber, and a step of forming an uneven pattern portion on the foamed resin layer. The mold has a cavity corresponding to the uneven pattern formed on the surface of the foamed resin layer. By making the inside of the chamber a negative pressure, the heating of the foamed resin layer is performed while the inside of the mold is made a negative pressure.

  In a preferred embodiment, in the step of forming the foamed resin layer, the foamed resin layer contains an unfoamed foaming agent. When heating the foamed resin layer, the unfoamed foaming agent foams, and the heating of the foamed resin layer is performed by heating the inside of the chamber.

  In a preferred embodiment, a suction hole for sucking air in the cavity is formed in the cavity of the mold.

  A manufacturing apparatus according to the present invention is a manufacturing apparatus for manufacturing a handrail, a resin layer forming apparatus for forming a foamed resin layer containing a foaming agent on a surface of a pipe member, and the pipe on which the foamed resin layer is formed. And a mold on which the member is arranged. The mold has a cavity corresponding to an uneven pattern formed on the surface of the foamed resin layer. A suction hole for sucking air in the cavity is formed in the cavity.

  In a preferred embodiment, the mold is a metal mold provided with a heater. The mold has a separable structure. The mold has a central opening for accommodating the pipe member on which the foamed resin layer is formed. The cavity is formed on a surface where the central opening is located.

  In a preferred embodiment, the resin layer forming device is an extrusion molding device including a head portion through which the pipe member passes. The extrusion molding apparatus is an apparatus that laminates a foamed resin layer containing a foaming agent and a coating layer located on an outer surface of the foamed resin layer on an outer surface of the pipe member. A suction tube communicating with the suction hole is connected to the mold.

  The production method according to the present invention is a method for producing a pipe structure having a foamed resin layer, comprising: a step of forming a foamed resin layer containing a foaming agent on the surface of a pipe member; and The method includes a step of arranging a pipe member in a mold and a step of forming an uneven pattern portion on the foamed resin layer. The mold has a cavity corresponding to the uneven pattern formed on the surface of the foamed resin layer.

  In a preferred embodiment, a suction hole for sucking air in the cavity is formed in the cavity. In the step of forming the concavo-convex pattern portion, heating the foamed resin layer is performed while applying a negative pressure to the inside of the cavity. In the step of forming the foamed resin layer, the foamed resin layer contains an unfoamed foaming agent. When the foamed resin layer is heated, the unfoamed foaming agent foams.

  In a preferred embodiment, the pipe member is a metal pipe. The step of forming the foamed resin layer is performed by extruding a resin material containing the foaming agent on the pipe member. In the step of forming the foamed resin layer, a coating layer is formed on an outer layer of the foamed resin layer. The uneven pattern portion is formed by changing the height of the surface of the coating layer.

  The handrail according to the present invention includes a foamed resin layer containing a foaming agent, and a concavo-convex pattern portion formed on the foamed resin layer, and a side surface defining the concavo-convex pattern portion extends substantially vertically and is 1 mm or more. Height.

  In a preferred embodiment, the concavo-convex pattern portion is at least one selected from the group consisting of a convex portion of a geometric pattern, a convex portion of a character, and a convex portion of a fiber shape. The substantially perpendicular angle is an angle in a range from 80 ° to 90 °. The height of the side surface defining the uneven pattern portion is 10 mm or less.

  In a preferred embodiment, a coating layer is formed on an outer layer of the foamed resin layer, and the uneven pattern portion is formed by changing a height of a surface of the coating layer.

  In a preferred embodiment, the concave-convex pattern portion is formed by suction while heating the foamed resin layer.

  In the present invention, after the foamed resin layer is formed on the surface of the pipe member, the pipe member is arranged in a mold, and then the uneven pattern portion is formed on the foamed resin layer. The mold has a cavity corresponding to the concave and convex pattern portion, and a suction hole is formed in the cavity. Then, in the step of forming the concavo-convex pattern portion, the foamed resin layer is heated while the inside of the cavity is under negative pressure. According to the present invention, when forming the uneven pattern portion in the foamed resin layer using a mold provided with a cavity corresponding to the uneven pattern portion, by heating the foamed resin layer while applying a negative pressure in the cavity. Thus, the expanding foamed resin layer can be brought into firm contact with the surface of the cavity. As a result, it is possible to stably form finely patterned portions on the foamed resin layer, and it is possible to form arbitrary patterns and irregularities on the surface of the handrail.

It is a sectional view showing typically the section structure of handrail 100 concerning an embodiment of the present invention. FIG. 3 is a perspective view showing a configuration of a pipe member 90. It is a perspective view showing an example of composition of handrail 100 concerning an embodiment of the present invention. 4 is a flowchart for explaining a method for manufacturing the handrail 100 according to the embodiment of the present invention. It is a perspective view showing composition of metallic mold 200 concerning an embodiment of the present invention. It is a perspective view showing composition of metallic mold 200 concerning an embodiment of the present invention. FIG. 2 is an enlarged view showing a configuration of a mold 200 according to the embodiment of the present invention. FIG. 3 is an enlarged view showing a cavity 38 of a mold 200. It is a perspective view showing composition of metallic mold 200 concerning an embodiment of the present invention. It is a perspective view showing an example of composition of handrail 100 concerning an embodiment of the present invention. FIG. 3 is an enlarged view showing an uneven pattern portion 60 of the handrail 100. It is a perspective view showing composition of extrusion molding device 300 concerning an embodiment of the present invention. 4 is a flowchart for explaining a method for manufacturing the handrail 100 according to the embodiment of the present invention. It is a figure showing handrail 100 (example) concerning an embodiment of the present invention. It is a figure showing handrail 100 (example) concerning an embodiment of the present invention. It is a figure showing handrail 100 (example) concerning an embodiment of the present invention. It is a figure showing handrail 100 (example) concerning an embodiment of the present invention. It is a figure showing handrail 100 (example) concerning an embodiment of the present invention. It is a figure showing handrail 100 (example) concerning an embodiment of the present invention.

  The inventor of the present application has found that a handrail made of a wooden material has a problem that the feel is good but the manufacturing cost is high, while a handrail made of a metal material has a problem of feeling cold and unpleasant. I was trying to fix the problem. When a foamed resin layer containing a foaming agent is formed on the surface of a handrail bar made of a metal material, coldness can be reduced by bubbles formed by the foaming agent. However, even if an attempt was made to form an uneven pattern on the foamed resin layer, a beautiful one could not be obtained. Even if the type and composition of the foaming agent and the resin were changed, and the conditions such as the temperature were variously changed, the uneven pattern could not be made clear. In such a situation, the idea of applying a negative pressure to the cavity of the mold for forming a pattern with irregularities was conceived, and the unfoamed component was left in the foamed resin layer containing the foaming agent. Was expanded while heating, and the inside of the cavity was sucked with a negative pressure, whereby a pattern with irregularities was successfully formed on the foamed resin layer, and the present invention was achieved.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the following drawings, for the sake of simplicity of description, the same reference numerals are given to members and portions having the same function, and duplicate description may be omitted or simplified. Further, the dimensional relationships (length, width, thickness, etc.) in each drawing may not always accurately reflect the actual dimensional relationships. In addition, matters other than matters specifically mentioned in the present specification and necessary for practicing the present invention can be grasped as design matters of a person skilled in the art based on conventional technology in the relevant field. The present invention can be implemented based on the contents disclosed in the specification and the drawings and common technical knowledge in the art. In addition, the present invention is not limited to the following embodiments.

  FIG. 1 shows a cross-sectional configuration of a handrail 100 according to an embodiment of the present invention. FIG. 2 shows the configuration of the pipe member 10 located at the center of the handrail 100 of the present embodiment. FIG. 3 is a perspective view showing the configuration of the handrail 100 according to the embodiment of the present invention.

  The pipe member 10 of the present embodiment is a circular pipe 90 made of metal (for example, aluminum, iron, copper, stainless steel, or the like). Specifically, the metal circular pipe 90 (pipe member 10) is an aluminum circular pipe. The pipe member 10 has an opening 15 at the center. The end surface of the pipe member 10 has a circular tube shape. Note that the pipe member 10 is not limited to the one made of a metal material, but may be another material (for example, made of resin, ceramic, or the like). In addition, the pipe member 10 is not limited to the shape of a circular tube, and may have other shapes (for example, an ellipse, an ellipse (track shape), a triangle, a square, a hexagon, a rotating body shape (a regular triangle, a square, a regular pentagon, A regular hexagon, a regular octagon, or an irregular shape).

  On the surface 10a of the pipe member 10, a foamed resin layer 20 is formed. The foamed resin layer 20 of the present embodiment is made of a resin material containing a foaming agent (21). The foaming agent (21) is added to a material (here, a resin material) and generates gas in the process of commercialization to generate foam in the product. The foaming agent (21) of the present embodiment is used for resin molding. By using the foaming agent (21), a foamable resin can be molded to produce a porous resin. The foaming agent (21) of the present embodiment is a substance that supplies a gas for forming bubbles in foam molding, and is roughly classified into a chemical foaming agent and a physical foaming agent (or foamable microcapsules). . The foaming agent for the foamable microcapsules is a physical foaming agent, but is handled similarly to a chemical foaming agent.

  A preferred example of the foaming agent (21) of the present embodiment is a thermal decomposition type foaming agent (particularly, a thermal decomposition type chemical foaming agent). The foaming agent (21) has a property of foaming by heat at the time of molding, starts foaming at a predetermined temperature, and the foaming ratio increases to some extent as the temperature increases. Chemical blowing agents are classified into organic blowing agents and inorganic blowing agents. Examples of the organic thermal decomposition type foaming agent include ADCA (azodicarbonamide), DPT (N, N'-dinitrosopentamethylenetetramine), OBSH (4,4'-oxybisbenzenesulfonylhydrazide) and the like. be able to. Examples of the inorganic thermal decomposition type blowing agent include hydrogen carbonate (for example, sodium bicarbonate (sodium hydrogen carbonate)), carbonate, and a combination of hydrogen carbonate and an organic acid salt. Determining the performance of the thermal decomposition type chemical blowing agent depends on the decomposition temperature, gas generation amount, particle size, and matching of the decomposition temperature and the molding temperature is also important, so it is suitable as appropriate based on those conditions. It is desirable to select a suitable foaming agent (21). A blend of a plurality of types of blowing agents may be used.

  The resin material (base material) constituting the foamed resin layer 20 of the present embodiment is, for example, PVC (polyvinyl chloride), TPE (thermoplastic elastomer), PVAc (polyvinyl acetate), or the like, but is not limited thereto. Instead, a suitable material is appropriately selected according to the characteristics of the foamed resin layer 20. Further, as the resin material (base material), a material obtained by blending a plurality of resin materials may be used. The amount of the foaming agent (21) added to the resin material (base material) is, for example, 5% or less (% by mass), for example, about 1% to 3% (% by mass). In addition, the addition amount of the foaming agent (21) is not limited to such an amount, and a suitable one can be appropriately selected according to various conditions.

  In the configuration of the present embodiment, the foamed resin layer 20 is formed by extruding a resin material containing a foaming agent (21). Further, in the configuration of the present embodiment, when the foamed resin layer 20 is formed, the foamed resin layer 20 includes the unfoamed foaming agent (21). Then, when the foamed resin layer 20 is heated (when heating the resin molding), the unfoamed foaming agent (21) foams, so that the uneven pattern portion 60 is formed on the foamed resin layer 20. The concavo-convex pattern portion 60 has a concavo-convex shape formed on the surface of the foamed resin layer 20 or a pattern formed by changing (different) surface height (for example, a geometric pattern, a figure of a character, Animal / plant figures, arbitrary figures / patterns (for example, handwritten style figures, randomly changing figures), etc. In the example shown in FIG. 3, an uneven pattern (graphic) having an elongated deformed elliptical shape (a slightly distorted elongated graphic) is formed on the foamed resin layer 20 as the uneven pattern portion 60. In the handrail 100 of the present embodiment, the coating layer 25 is formed on the outer layer of the foamed resin layer 20, and the uneven pattern portion 60 is formed on the coating layer 25. The coating layer 25 is a protective layer (resin layer) that protects the foamed resin layer 20. In the coating layer 25 of the present embodiment, antibacterial properties, antifungal properties, chemical resistance, weather resistance, abrasion resistance, stain resistance, fire resistance, wood grain pattern, and the like (at least one of them) are provided. can do. The coating layer 25 of the present embodiment is composed of, for example, a blend of an auxiliary agent (for example, a blend of a component that imparts a property such as an antibacterial agent) to a base material such as PVC, TPE, ABS, or PE. . When the foamed resin layer 20 does not need to be protected, the coating layer 25 may not be provided. However, it is preferable to provide the coating layer 25 in consideration of the characteristics and use of the handrail 100.

  When the thickness of the handrail 100 of the present embodiment is exemplarily shown, assuming that the thickness of the pipe member 10 is 100 units (here, 2 mm), the thickness of the foamed resin layer 20 is 50 to 200 units (here, The thickness of the coating layer 25 is 100 units or less (here, 50 units or less, ie, 1 mm or less (or 0.5 mm or less)). Note that the thickness (or diameter) of each layer (10, 20, 25) varies depending on the required handrail 100, and a specific thickness (or diameter) is appropriately selected as appropriate. can do.

  In the configuration example shown in FIG. 3, an uneven pattern portion 60 is formed on the surface of the handrail 100 of this embodiment (here, the surface 25 a of the coating layer 25). The illustrated concavo-convex pattern portion 60 includes a convex portion 61 (geometric figure or an arbitrary pattern) and a concave portion 62 located between the convex portions 61. In the illustrated configuration example, the concave portion 62 is the same as a region 69 (non-formed region) in which the concavo-convex pattern portion 60 is not formed. However, the concave portion 62 may be formed to be lower than the non-formed region 69. The convex portion 61 of the present embodiment includes a pattern portion (pattern surface) 61a that defines a pattern or a figure, and a connection portion (connection surface or inclined surface) 61b that connects the pattern portion 61 and the non-formation region 69. It is configured. When the coating layer 25 is not formed, the uneven pattern portion 60 is formed on the surface (20a) of the foamed resin layer 20. Further, a further outer layer (for example, a transparent clear layer or a coloring layer (including a translucent color layer, a metal color layer and the like)) may be formed outside the coating layer 25.

  In the configuration of the present embodiment, a plurality of uneven pattern portions 60 are formed on the handrail 100. In the illustrated example, a plurality of the concavo-convex pattern portions 60 are formed in a lined-up form, but the concavo-convex pattern portions 60 may be formed in other forms. For example, the concavo-convex pattern portions 60 may be connected to form a single convex portion 61, or the concavo-convex pattern portions 60 may be arranged in a zigzag instead of in a single row. Further, in the embodiment shown in FIG. 3, the concavo-convex pattern portion 60 is formed on the upper side in the drawing, but the concavo-convex pattern portion 60 may be formed on the lower side (both upper and lower sides) in addition to the upper side. Alternatively, the concavo-convex pattern portion 60 may be formed on the horizontal side (right side and / or left side) in the drawing. The height of the convex portion 61 in the concave-convex pattern portion 60 is, for example, 0.1 mm or more and 1.5 mm or less (or 1.0 mm to 5 mm) based on the surface of the non-formation region 69. The present invention is not limited thereto, and a suitable one can be determined as appropriate while considering various conditions (manufacturing conditions, use conditions, cost conditions, etc.) required for the handrail 100.

  Although the illustrated handrail 100 is shown as a straight line (a pipe member on a straight line) for the purpose of explanation, it is bent by processing (for example, bent at 90 ° or a predetermined angle). (Such as bent to 60 °).

  Next, a method for manufacturing the handrail 100 of the present embodiment will be described with reference to FIG. FIG. 4 is a flowchart illustrating a method for manufacturing the handrail 100 according to the present embodiment.

  In the method for manufacturing the handrail 100 of the present embodiment, after preparing the pipe member 10, the foamed resin layer 20 containing the foaming agent (21) is formed on the surface 10 a of the pipe member 10. Next, the pipe member 10 (handrail pipe) on which the foamed resin layer 20 is formed is placed in a mold. Subsequently, the uneven pattern portion 60 is formed on the foamed resin layer 20. Hereinafter, this will be described in more detail.

  As shown in FIG. 4, first, a pipe member 10 is prepared (step S100). The pipe member 10 of the present embodiment is an aluminum pipe, but may be another pipe member (for example, a stainless steel pipe, a resin pipe, or the like).

  Next, the foamed resin layer 20 is formed on the surface 10a of the pipe member (aluminum pipe) 10 (Step S200). Specifically, the foamed resin layer 20 is formed by applying a resin material containing a foaming agent (21) to the surface 10a of the pipe member 10. In the present embodiment, the foaming agent (21) is, for example, an inorganic foaming agent (trade name: Cell Microphone), microcapsule (trade name: Expancel), or the like. A plurality of types of foaming agents (21) can be blended and used. The resin material serving as the base material is, for example, PVC, TPE, PVAc, or the like. A plurality of types of resin materials can be blended and used. The addition amount of the blowing agent (21) is, for example, 1 to 3% (% by mass).

  In this embodiment, the foamed resin layer 20 and the coating layer 25 are formed on the surface 10a of the pipe member 10 by an extrusion molding method using a crosshead extrusion molding machine. Specifically, the laminated film of the foamed resin layer 20 and the coating layer 25 is formed on the surface 10a of the pipe member 10 at one time by passing the pipe member 10 through the head portion of the crosshead extrusion molding machine ( Two-layer extrusion). In this way, a straight handrail pipe (the pipe member 10 on which the foamed resin layer 20 is formed) (manufactured by the foam resin layer 20) is manufactured. The foamed resin layer 20 (and the coating layer 25) may be formed on the pipe member 10 by another molding method.

  In the step (S200) of forming the foamed resin layer 20 of the present embodiment, the foamed resin layer 20 is formed so as to include the unfoamed foaming agent (21). Therefore, in the step of forming the foamed resin layer 20, the resin molding is performed at as low a temperature as possible. However, in order to perform resin molding, a heating temperature of at least 135 ° C. to 150 ° C. is required for resin molding. Therefore, even at that temperature, a blowing agent (21) containing an unfoamed foaming agent (21) is used. ) Is required. In the configuration example of the present embodiment, the resin material of the base material is PVC, and the resin is molded at a molding heating temperature of 165 ° C. (or a temperature range of 130 ° C. to 170 ° C.). A foaming agent (for example, an inorganic foaming agent or microcapsule) that remains in a state is used. In the subsequent step, when the resin-molded foamed resin layer 20 is heated, the non-foamed foaming agent foams to form the uneven pattern portion 60.

  Next, the handrail pipe (the pipe member 10 on which the foamed resin layer 20 is formed) is placed in a mold (step S300). 5 and 6 are views showing the configuration of the mold 200 of the present embodiment. The mold 200 of the present embodiment has a configuration (separable configuration) that can be disassembled into a first mold (lower mold) 31 and a second mold (upper mold) 32. FIG. 5 shows a configuration of the mold 200 (31, 32) of the present embodiment viewed from above. FIG. 6 shows a configuration of the mold 200 (31, 32) viewed from the horizontal direction.

  In the mold 200 of the present embodiment, a cavity 38 is formed in a first mold (lower mold) 31. The cavity 38 has a shape corresponding to the uneven pattern portion 60. In the mold 200 of the present embodiment, only the first mold (lower mold) 31 corresponds to the shape of the handrail 100 shown in FIG. 3 (particularly, the arrangement and shape of the uneven pattern portion 60). A cavity 38 is formed. However, depending on the shape of the handrail 100 (particularly, the arrangement and shape of the uneven pattern portion 60), the cavity 38 may be formed in the second die (upper die) 32, and the first die 31 and the A cavity 38 may be formed in both of the second molds 32.

  In the mold 200 of the present embodiment, a central opening 35 (35A, 35B) is formed. The pipe member 10 (handrail pipe) on which the foamed resin layer 20 is formed can be arranged in the central opening 35. In the illustrated example, a cavity 38 corresponding to the shape (structure) of the concavo-convex pattern portion 60 is formed on the surface of the central opening 35A of the first mold 31. In each cavity 38, a suction hole 39 for sucking air in the cavity 38 is formed. Further, a suction pipe 40 communicating with the suction hole 39 is connected to the mold 200 (31). In the configuration example of the present embodiment, the suction pipe 40 is connected to a part (air hole) of the mold 31 via a connection member (connection member) 41. A part (air hole) of the mold 201 is connected to the suction hole 39 through the inside of the mold.

  The mold 200 of the present embodiment includes a mold body 30 made of metal (here, aluminum). A central opening 35 (35A, 35B) is formed at the center of the mold body 30. An upper surface (contact surface) 33 is formed around the center opening 35 (opening end). The upper surfaces 33 are in contact with each other, and the first mold 31 and the second mold 32 are integrated. In the configuration example of the present embodiment, the projections 36 are provided on the first mold 31 in order to prevent displacement when the first mold 31 and the second mold 32 are matched. In addition, the second mold 32 is provided with a concave portion 37 that fits with the projection 36. In the combination of the protrusion 36 and the recess 37, the first mold 31 and the second mold 32 may be reversed. Alternatively, a joining mechanism other than the protruding portion 36 and the recessed portion 37 (for example, a fitting mechanism of unevenness or waveforms fitting each other, a joining mechanism by magnetic force, or the like) may be adopted.

  FIG. 7 shows a part of the first mold 31 in an enlarged manner. FIG. 8 shows the structure of the cavity 38 in an enlarged manner. At the bottom of the center opening 35A of the first mold 31, cavities 38 are formed in a line at equal intervals. The cavity 38 of the present embodiment includes a bottom portion 31u corresponding to the pattern portion (pattern surface) 61a of the uneven pattern portion 60, and a peripheral portion (inclined portion) 31e located around the bottom portion 31u. A suction hole 39 for sucking the air in the cavity 38 is formed in the bottom surface 31u of the cavity 38. The bottom surface 31u of the cavity 38 is connected to the surface (the mold contact surface 31b) of the center opening 35A via the peripheral edge 31e.

  FIG. 9 shows a state where the first mold 31 and the second mold 32 are combined. More specifically, as shown in FIG. 5 or FIG. 6, with the mold 200 opened, a handrail pipe (foam resin) is inserted into the center opening 35 of the first mold 31 (or the second mold 32). The pipe member 10) on which the layer 20 is formed is set. Next, when the first mold 31 and the second mold 32 are overlapped with the handrail pipe set, a state shown in FIG. 9 is obtained. Further, the mold 200 of the present embodiment is provided with a heater, and the mold 200 can be heated by the heater. The heater of the present embodiment is, for example, a rod-shaped heater, and the heater is directly attached to a metal mold 200. Then, a temperature sensor can be attached to the mold 200, and temperature control can be performed so that the temperature becomes a constant temperature (or an appropriate temperature or a set temperature).

  Next, the mold 200 on which the handrail pipe is set is heated (Step S310). Specifically, by heating the mold 200, the foamed resin layer 20 of the handrail pipe is heated. Since the unfoamed foaming agent (21) foams by heating the mold 200, the mold 200 is firmly fixed (tightened) so as to withstand the expansion of the foaming. The heating of the mold 200 (or the heating of the foamed resin layer 20) is performed at a predetermined temperature (appropriate temperature) for a predetermined time (appropriate time). After the predetermined heating, the temperature may be kept warm, or the heating may be stopped and left for a certain time. In one example of the heating step (S310) of the present embodiment, the resin material of the base material is PVC and a foaming agent (for example, an inorganic foaming agent, microcapsule), and the heating temperature is 165 ° C (or 150 ° C to 180 ° C). Is performed for 20 minutes to 30 minutes.

  Further, the inside of the mold 200 (particularly, the inside of the cavity 38) is sucked together with the heating step of the mold 200 (S310) (Step S320). Specifically, the inside of the cavity 38 is set to a negative pressure. This suction step (S320) may be started at the same time as the mold heating step (S310), or may be performed before the mold heating step (S310). Alternatively, the suction step (S320) may be performed after the mold heating step (S310) is started. In addition, the suction step (S320) may be ended at the same time as the mold heating step (S310), or the suction step (S320) may be ended after the mold heating step (S310). Good. Alternatively, the suction step (S320) may be completed before the mold heating step (S310) is completed. Suitable start and end timings can be appropriately determined in accordance with various conditions (manufacturing process, manufacturing equipment, required product specifications, and the like).

  In the suction step (S320) of the present embodiment, the inside of the cavity 38 is reduced in pressure (negative pressure) by the suction hole 39 connected to the suction pipe 40. The suction pipe 40 is connected to a decompression device (vacuum pump), and can operate the decompression device (vacuum pump) to reduce the pressure inside the cavity 38 to a negative pressure. The pressure reducing capability of the pressure reducing device (vacuum pump) is, for example, 0.03 to 0.08 MPa (attained vacuum degree).

  By applying a negative pressure inside the cavity 38 while heating the mold 200, the unfoamed foaming agent (21) foams (expands), and the resin material containing the foaming agent (21) firmly fills the inside of the cavity 38. Filling is performed, thereby forming an uneven pattern portion 60 having unevenness (pattern) (step S350). According to the experiment of the present inventor, even if the unfoamed foaming agent (21) is foamed (expanded) and filled into the cavity 38 without applying a negative pressure to the cavity 38, the cavity 38 cannot be filled well. The pattern pattern 60 having the pattern (pattern) could not be formed cleanly. After a number of failures, a method has been conceived in which the unfoamed foaming agent (21) foams (expands) while maintaining a negative pressure in the cavity 38, whereby the concavo-convex pattern portion 60 can be formed neatly. .

  Although the heating temperature and the heating time of the present embodiment vary depending on the material used and the manufacturing conditions, in one example, the heating temperature is 150 ° C. to 180 ° C., and the heating time is 20 minutes to 30 minutes. After the step of forming the concavo-convex pattern portion 60 (S350), the heating is stopped and the temperature of the mold 200 is reduced to a temperature equal to or lower than the softening temperature of the resin material. Subsequently, the mold 200 is opened, and the handrail 100 (handrail pipe) of the present embodiment is taken out (step S400). Thus, the handrail 100 on which the uneven pattern portion 60 is formed (the handrail 100 with the unevenness (pattern)) can be obtained (step S500).

FIG. 10 shows the configuration of the handrail 100 manufactured by the manufacturing method of the present embodiment, and the viewing angle is different from that shown in FIG. FIG. 11 is an enlarged view of the uneven pattern portion 60 of the handrail 100. As shown in FIG. 11, according to the manufacturing method of the present embodiment, the unfoamed foaming agent (21) foams (expands), and the resin material containing the foaming agent (21) fills the cavity 38 firmly. As a result, the concavo-convex pattern portion 60 can be formed neatly (as intended or as designed).

  In the manufacturing method of the present embodiment, after preparing the pipe member 10 (step S100), the foamed resin layer 20 is formed on the surface 10a of the pipe member 10 (step S200), and subsequently, the pipe member (handrail pipe) Is placed in the mold 200 (step S300). Next, while heating the mold (step S320), the inside (38) of the mold 200 is sucked (step S320). Thus, the uneven pattern portion 60 is formed on the foamed resin layer 20 (step S350). The mold 200 of the present embodiment has a cavity 38 corresponding to the concave and convex pattern portion 60, and a suction hole 39 is formed in the cavity 38. Then, in the step of forming the concavo-convex pattern portion 60 (step S350), the foamed resin layer 20 is heated while the inside of the cavity 38 is under a negative pressure. According to the method of the present embodiment, when forming the concave and convex pattern portion 60 in the foamed resin layer 20 using the mold 200 in which the cavity 38 corresponding to the concave and convex pattern portion 60 is provided, the inside of the cavity 38 is negative. By heating the foamed resin layer 20 while applying pressure, the expanded foamed resin layer 20 can be brought into firm contact with the surface of the cavity 38. As a result, it is possible to stably form the uneven pattern portion 60 neatly on the foamed resin layer 20, so that it is possible to form an arbitrary pattern and unevenness on the surface (100a) of the handrail (100).

  In the present embodiment, a heater is attached to the mold 200 and the mold 200 is heated by the heater. However, another method (heating method) may be adopted as long as the mold 200 can be heated at a set temperature for a predetermined time. . For example, after arranging the pipe member 10 (handrail pipe) on which the foamed resin layer 20 is formed in the mold 200, the mold 200 is placed in an oven (for example, a furnace such as a gear oven or a dryer) and fixed. The temperature (or desired set temperature) may be maintained for a fixed time (or a desired predetermined time). Alternatively, after disposing the pipe member 10 (handrail pipe) on which the foamed resin layer 20 is formed in the mold 200, the mold 200 is hung in an oven (a drying oven or the like), and left there at a predetermined temperature for a predetermined time. You may. In addition, any heating device (heating means) that can be heated to a certain temperature and maintained at a certain level of accuracy can be employed.

  FIG. 12 schematically shows a configuration of a resin layer forming apparatus 300 used in the manufacturing method of the present embodiment. The resin layer forming apparatus 300 of the present embodiment is an apparatus for forming the foamed resin layer 20 containing the foaming agent (21) on the surface 10a of the pipe member 10. The resin layer forming device 300 shown in FIG. 12 is an extrusion device (in this example, a crosshead extrusion device) provided with a head portion 310 through which the pipe member 10 passes. When the pipe member 10 is passed through the opening 315 of the head portion 310 using the illustrated extrusion molding device (crosshead extrusion molding device), a lower layer material (a resin base material made of a general-purpose resin material) is formed on the surface 10 a of the pipe member 10. And a surface layer material (a coating layer 25 made of a general-purpose resin material). In other words, two-layer extrusion molding of the lower layer material (foam resin layer 20) and the surface layer material (coating layer 25) can be performed.

  In the resin layer forming apparatus (crosshead extrusion molding apparatus) 300 of the present embodiment, an extrusion molding main body 320 that extrudes a resin material, a connection section 322 that connects the extrusion molding main body 320 and the head section 310, and a resin material ( And an input port 350 for inputting resin pellets or the like. On the front side 311 and the back side 322 of the head section 310, transport devices (here, a roller conveyor 400 or a belt conveyor) 400A and 400B are provided, respectively. When the pipe member 10 is inserted into the opening 315 on the front side 311 of the head 310 from the transport device 400A, the foamed resin layer 20 with the coating layer 25 is applied to the surface 10a of the pipe member 10. In the resin layer formation by the resin layer forming apparatus (extrusion molding apparatus) 300 (step S200), a low temperature (a predetermined temperature higher than the foaming start point (foaming) so as not to foam all the foaming agent. The resin molding is performed at a temperature lower than the starting point by about 15 ° C. (for example, about 130 ° C. to 150 ° C.) In this manner, the foamed resin layer 20 containing the unfoamed foaming agent (21) Is formed on the pipe member 10. At this stage, a straight (no uneven pattern portion, that is, no dimple) handrail pipe is formed, and then the handrail pipe is arranged in the mold 200 to form the uneven handrail pipe. The part 60 will be formed.

  In the manufacturing method according to the present embodiment, the suction hole 39 is provided in the cavity 38 of the mold 200, and the suction tube 40 is communicated with the suction hole 39, so that the inside of the cavity 38 is reduced in pressure (negative pressure). The inside of the cavity 38 may be reduced in pressure (negative pressure) by using another method. FIG. 13 is a flowchart illustrating a modification of the manufacturing method according to the present embodiment.

  In the manufacturing method shown in FIG. 13, similarly to the step S300 shown in FIG. 4, after the handrail pipes (10, 20) are put into the mold 200 (step S300), the mold 200 is put into the chamber (step S300). Step S600). When mass-producing the handrail 100 of the present embodiment, not only one mold 200 but also a plurality (for example, ten or more) of the molds 200 can be put in the chamber.

  Next, a negative pressure is applied to the inside of the cavity 38 of the mold 200 by reducing the pressure in the chamber (step S610). As shown in FIG. 8, a suction hole 39 may be provided in the bottom surface 31u of the cavity 38, and a negative pressure may be applied to the inside of the cavity 38 through the suction hole 39. The inside of the cavity 38 may be made to have a negative pressure in conjunction with the state) (for example, the cavity 38 and the chamber may be connected not through the suction hole 39 but through another communicating space (passage)). .

  Next, the inside of the chamber is heated, whereby the mold 200 arranged in the chamber is heated (step S620). By the heating, the foamed resin layer 20 arranged in the mold 200 is further foamed (step S630). This foaming is due to the expansion of the foaming agent in the unfoamed state of the foamed resin layer 20, whereby the foamed resin layer 20 is filled in the cavity 38, and the concavo-convex pattern portion 60 (concavo-convex or pattern) is formed. (Step S650).

  Subsequently, after stopping the heating and decompression of the chamber, the mold 200 is taken out of the chamber (Step S700), and then the handrail 100 (handrail pipe) of the present embodiment is removed from the mold 200 (Step S710). . When a plurality of molds 200 are arranged in the chamber, all the molds 200 are taken out of the chamber, and the handrail 100 (handrail pipe) is removed from the mold 200. In this way, a handrail 100 having irregularities (patterns) is obtained (step S800).

  The manufacturing method shown in FIG. 13 has an advantage that when a plurality of dies 200 are used, it is not necessary to set the suction tube 40 in each of the dies 200. Further, even if a heater is not provided in each mold 200, there is an advantage that a plurality of molds 200 can be heated at once by heating in a heating type chamber. Therefore, it is suitable for manufacturing a large number of handrails 100.

  Next, a handrail 100 (example) manufactured by the method of the present embodiment will be described with reference to FIGS.

  The handrail 100 shown in FIG. 14 has a structure in which an annular convex portion 61 and an annular concave portion 62 are alternately and neatly formed as the uneven pattern portion 60. Such a clean wavy surface cannot be realized by the conventional manufacturing method, but can be realized by the manufacturing method of the present embodiment. In the concavo-convex pattern portion 60 shown in FIG. 14, a first convex portion (high annular convex portion) 61C having a height and a second convex portion (low annular convex portion) 61D having a height lower than that of the first convex portion are provided. Are alternately arranged with the concave portion 62 interposed therebetween. The annular convex portions 61 (for example, 61C or 61D) having the same height may be arranged with the concave portion 62 interposed therebetween, or the annular convex portions 61 having different heights may be arranged. In this example, the difference in height between the top of the first convex portion (high annular convex portion) 61C and the surface of the non-forming region 69 (or the bottom surface of the concave portion 62) is, for example, 5 mm (or more). is there. The difference in height between the second convex portion (low annular convex portion) 61D and the surface of the non-forming region 69 (or the bottom surface of the concave portion 62) is, for example, 2 mm (or 3 mm or more). . The upper limit of the height is not particularly limited, but is, for example, 10 mm or less, or 7 mm (or 5 mm) or less.

  In the handrail 100 shown in FIG. 15, a convex portion 61 </ b> E (61) having the shape of a playing card mark is formed as the concave / convex pattern portion 60. In the configuration shown in FIG. 15, the side surface (wall surface) 61s of the convex portion 61 extends substantially vertically (for example, 80 ° or more (or 85 ° or more), 90 ° or less). Such a structure in which the side surface 61s extends substantially vertically is realized by the manufacturing method of the present embodiment. In order to form the substantially vertical side surface 61s cleanly, it is preferable to optimize the temperature condition and the evacuation condition. In the present embodiment, in the mold heating step (S310) and the suction step (S320), the evacuation time (for example, 1 minute or less) is longer than the heating time (for example, 7 minutes or more, or 9 minutes or more). ) Is shortened. However, it is preferable that optimum conditions (temperature conditions and evacuation conditions) are appropriately determined according to the resin used, dimensions, the shape of the concavo-convex pattern portion 60, and the like. The difference between the height of the convex portion 61E (a convex pattern having a playing card shape or a geometric mark shape) and the surface of the non-forming region 69 is, for example, 2 mm (or 3 mm or more). . The upper limit of the height is not particularly limited, but is, for example, 10 mm or less, or 7 mm (or 5 mm) or less.

  In the handrail 100 shown in FIG. 16, as the concavo-convex pattern portion 60, a convex portion 61F of a pattern mainly composed of curves (here, footprint marks), a convex portion 61G (61) of a gentle curve, and playing cards The projection 61E (61) having the shape of the mark is formed on the same surface. The side surface 61s of the protrusion 61F of the footprint mark has a clean, substantially vertical surface. In addition, the side surface 61t of the gentle curved convex portion 61G is not vertical but a mountain-shaped inclined surface. In this embodiment, such different patterns (61F, 61G) can be formed on the same surface.

  Further, a handrail 100 as shown in FIG. 17 can be manufactured. In the configuration shown in FIG. 17, the projection 61E (a playing card mark) shown in FIG. 15 is formed on the lower surface in the figure, and the projection 61F (a footprint mark) and the projection shown in FIG. A portion 61G (a mountain-shaped gentle convex mark) is formed. According to the present embodiment, different marks (concave and convex pattern portions 60) on the upper surface (one side) and the lower surface (the other side) can be manufactured in one manufacturing process.

  In the handrail 100 shown in FIG. 18, as the concavo-convex pattern portion 60, a convex portion 61 </ b> H formed of a logo mark (brand mark, company logo, etc.) and a convex portion 61 </ b> X formed of characters (kanji, symbols, katakana / hiragana or alphabet). And are formed on the same surface. The height of the protrusion 61X (the height of the side surface 61s) is, for example, 0.5 mm or more and 5 mm or less (in one example, 1 to 2 mm). Such a beautiful character convex portion 61X cannot be realized by the conventional manufacturing method, but can be realized by the manufacturing method of the present embodiment.

  Further, in the handrail 100 shown in FIG. 19, a fibrous convex portion 61Y is formed as the concave / convex pattern portion 60. The length of the fibrous projection 61Y is, for example, 3 mm to 10 mm (in one example, 5 mm). The diameter (thickness) of the fibrous projection 61Y is, for example, 0.5 mm to 2 mm (1 mm in one example). Such a clean fibrous convex portion 61Y cannot be realized by the conventional manufacturing method, but can be realized by the manufacturing method of the present embodiment. In addition, the fibrous convex portion 61Y can be formed on the same handrail 100 (for example, opposite surfaces or the same surface) as the convex portion 61X of the character shown in FIG.

  As described above, the present invention has been described by the preferred embodiments. However, such description is not a limitation, and various modifications are possible. In the above-described embodiment, a handrail is described as an example of a pipe structure having a foamed resin layer. However, the technique of the embodiment of the present invention is not limited to handrails, and other pipe structures (for example, aluminum Pipe, iron pipe, SUS pipe). Further, other modifications such as an elliptic pipe, a square pipe, a flat bar, and an aluminum deformed product may be performed. When the technology of the present embodiment (including the technology of “pipe structure containing unfoamed foaming agent”) is applied, the structure of the pipe structure can be designed and constructed (manufactured) relatively freely. Since it is possible, the grip of the handrail is improved (for example, a structure that does not slip even if there is no grip force), or a sealing material such as a pipe is manufactured (inserted into a hole of a pipe or the like, and then heat is applied. Or expands to provide a water-stopping effect, etc.), or is used as an airtight material for buildings and housing sashes, etc. You may. Further, a modification may be made to improve productivity by simultaneously executing a plurality of manufacturing steps (for example, a molding step in two steps).

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the handrail which can form arbitrary patterns and irregularities on a handrail surface can be provided.

10 Pipe members (aluminum pipes)
Reference Signs List 20 foamed resin layer 25 coating layer 30 mold body 35 center opening 38 cavity 39 suction hole 40 suction tube 60 uneven pattern portion 61 convex portion 62 concave portion 69 non-formed area 90 pipe member 100 handrail 200 mold 300 resin layer formation Equipment (extrusion molding equipment)
310 Head unit 400 (400A, 400B) Transfer device

Claims (12)

A method for manufacturing a handrail,
Forming a foamed resin layer containing a foaming agent on the surface of the pipe member,
A step of disposing the pipe member on which the foamed resin layer is formed in a mold,
Forming a concave and convex pattern portion on the foamed resin layer,
The mold has a cavity corresponding to the uneven pattern portion formed on the surface of the foamed resin layer,
A suction hole for sucking air in the cavity is formed in the cavity,
The manufacturing method, wherein in the step of forming the uneven pattern portion, the foamed resin layer is heated while a negative pressure is applied to the inside of the cavity. In the step of forming the foamed resin layer, the foamed resin layer contains an unfoamed foaming agent,
The method according to claim 1, wherein the unfoamed foaming agent foams when the foamed resin layer is heated. The pipe member is a circular metal pipe,
The step of forming the foamed resin layer is performed on the pipe member by extruding a resin material containing the foaming agent,
In the step of forming the foamed resin layer, a coating layer is formed on an outer layer of the foamed resin layer,
The method according to claim 1, wherein the uneven pattern portion is formed by changing a height of a surface of the coating layer. The mold is a metal mold provided with a heater,
The mold has a separable structure,
The mold has a central opening in which the pipe member on which the foamed resin layer is formed is housed,
The cavity is formed on a surface where the central opening is located,
The method according to claim 1, wherein a suction pipe communicating with the suction hole is connected to the mold, and the heating of the foamed resin layer is performed by the heater. A method for manufacturing a handrail,
Forming a foamed resin layer containing a foaming agent on the surface of the pipe member,
A step of disposing the pipe member on which the foamed resin layer is formed in a mold,
Arranging the mold in which the pipe member is arranged in a chamber;
Forming a concave and convex pattern portion on the foamed resin layer,
The mold has a cavity corresponding to the uneven pattern portion formed on the surface of the foamed resin layer,
A manufacturing method, wherein the foaming resin layer is heated while the inside of the mold is under a negative pressure by making the inside of the chamber a negative pressure. In the step of forming the foamed resin layer, the foamed resin layer contains an unfoamed foaming agent,
When heating the foamed resin layer, the foaming agent in the unfoamed state foams,
The manufacturing method according to claim 5, wherein the heating of the foamed resin layer is performed by heating the inside of the chamber.   The method according to claim 5, wherein a suction hole for sucking air in the cavity is formed in the cavity of the mold. A manufacturing apparatus for manufacturing handrails,
A resin layer forming apparatus for forming a foamed resin layer containing a foaming agent on the surface of a pipe member,
And a mold in which the pipe member on which the foamed resin layer is formed is disposed.
The mold has a cavity corresponding to an uneven pattern portion formed on the surface of the foamed resin layer,
A manufacturing apparatus, wherein a suction hole for sucking air in the cavity is formed in the cavity. The mold is a metal mold provided with a heater,
The mold has a separable structure,
The mold has a central opening in which the pipe member on which the foamed resin layer is formed is housed,
The manufacturing apparatus according to claim 8, wherein the cavity is formed on a surface where the central opening is located. The resin layer forming device is an extrusion molding device including a head portion through which the pipe member passes,
The extrusion molding device is a device that is formed by laminating a foamed resin layer containing a foaming agent and a coating layer located on the outer surface of the foamed resin layer on an outer surface of the pipe member,
The manufacturing apparatus according to claim 8, wherein a suction pipe communicating with the suction hole is connected to the mold. A method for manufacturing a pipe structure having a foamed resin layer,
Forming a foamed resin layer containing a foaming agent on the surface of the pipe member,
A step of disposing the pipe member on which the foamed resin layer is formed in a mold,
Forming a concave and convex pattern portion on the foamed resin layer,
The mold has a cavity corresponding to the uneven pattern portion formed on the surface of the foamed resin layer,
A suction hole for sucking air in the cavity is formed in the cavity,
In the step of forming the concavo-convex pattern portion, while performing a negative pressure in the cavity, heating the foamed resin layer,
In the step of forming the foamed resin layer, the foamed resin layer contains an unfoamed foaming agent,
The method according to claim 1, wherein the unfoamed foaming agent foams when the foamed resin layer is heated. The pipe member is a circular metal pipe,
The step of forming the foamed resin layer is performed on the pipe member by extruding a resin material containing the foaming agent,
In the step of forming the foamed resin layer, a coating layer is formed on an outer layer of the foamed resin layer,
The manufacturing method according to claim 11, wherein the uneven pattern portion is formed by changing a height of a surface of the coating layer.

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