JP2011158007A - Thermal fusion tool for resin pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermal fusion tool for a resin pipe capable of increasing a fusion area of an end of a resin pipe, capable of enhancing bonding strength and sealing performance of a bonding part of the end of the resin pipe, and capable of facilitating bonding work of the end of the resin pipe. <P>SOLUTION: The thermal fusion tool for the resin pipe arranged between the ends of the resin pipe and bonding the ends of the resin pipe by thermal fusion by supplying electricity includes an annular sheet-like substrate 11 made of an electric insulating material, a heating wire 25 wound between an inner peripheral end and an outer peripheral end of the sheet-like substrate 11, and annular sheet-like cover materials 31A made of an electric insulating material and attached to both surfaces of the sheet-like substrate 11 to which the heating wire 25 is wound. Both ends of the heating wire 25 are used as connection parts with the power source. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a heat fusion tool for joining resin pipes by heat fusion.

  2. Description of the Related Art Conventionally, a resin pipe having a predetermined length is joined at a construction site in view of problems in transportation, problems in construction of a building, and the like. In addition, heat sealing is also performed between ends of a tubular covering material that covers the pipe. However, a joining operation using a bulky joining device is not easy in a high place or a narrow place.

  As a heat fusion tool for heat fusion between the end portions of the covering material, a heat fusion tool in which a heating member for electric heating having a hole is provided on an annular sheet-like substrate has been proposed. In the joining method using the heat-sealing tool, the heat-sealing tool is arranged between the end portions of the covering material to be joined, and the heating member of the heat-sealing tool is energized, and the covering material is heated by the heat of the heating member generated by the energization. By melting the end portions, the end portions of the covering material are heat-sealed and joined through the hole portions of the heating member.

  If the said heat welding tool is used, the joining operation | work of the resin pipe (the coating | covering material of piping, or piping itself) in a high place or a narrow place can be performed easily. However, the joint portion of the resin pipe is better as the sealing property and the joining strength are higher, and further improvement in the sealing property and the joining strength is required. In addition, when setting the heat-sealing tool between the ends of the resin tube, the heat-sealing tool may easily slide with respect to the end of the resin tube, and care must be taken to ensure that it is in the correct position.

JP 2009-204109 A

  The present invention has been made in view of the above points, and can improve the sealing performance and bonding strength of the joint portion of the resin tube end portion, and can easily perform positioning with respect to the end portion of the resin tube. An object is to provide a heat fusion tool for resin pipes.

  The invention according to claim 1 is a resin pipe heat-sealing device that is disposed between the end portions of the resin pipe and energized to join the end portions of the resin pipe. A heating wire is wound around a portion between an inner peripheral edge and an outer peripheral edge of the annular sheet-like base material, and both ends of the heating wire are connected to a power source.

  The invention according to claim 2 is the heating wire fixing notch according to claim 1, wherein heating wire fixing cutouts are formed at a plurality of locations on the inner and outer peripheral edges of the sheet-like base material, and the heating wires are fitted into the heating wire fixing notches. Is wound around a sheet-like substrate.

  A third aspect of the invention is characterized in that, in the first or second aspect, the sheet-like substrate is made of a heat-meltable material.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the dividing portion that is divided between the inner peripheral edge and the outer peripheral edge of the sheet base material and passes through the inside and the outside of the heat-sealing tool is the sheet base. It is formed in a material.

  The invention of claim 5 is characterized in that, in claim 1 or 2, an annular sheet-like cover material made of an electrically insulating material is bonded to both surfaces of the sheet-like substrate around which the heating wire is wound. And

  According to a sixth aspect of the present invention, in the fifth aspect, a flange projecting outward is formed on one or both of the inner peripheral edge and the outer peripheral edge of the sheet-like cover material, and the flange of the inner peripheral edge is formed of the resin pipe. The outer peripheral edge flange is an outer peripheral edge positioning portion that is fitted to the outer peripheral edge of the end portion of the resin pipe.

  The invention of claim 7 is the invention according to claim 5 or 6, wherein the sheet-like base material and the sheet-like cover material are divided between the inner and outer peripheral edges and the dividing portion passing through the inside and the outside of the heat-sealing tool is It is formed in the sheet-like base material and the said sheet-like cover material, It is characterized by the above-mentioned.

  The invention of claim 8 is characterized in that, in any one of claims 5 to 7, the sheet-like base material and the sheet-like cover material are made of a heat-meltable material.

  A resin pipe heat fusion tool (hereinafter referred to as a fusion tool) according to the first aspect of the present invention is disposed between the ends of the resin pipe and energizes the heating wire to generate heat. The end of the resin tube that is in contact with the tool is heated and fused to the heat-sealing tool, and the end of the resin tube can be joined via the heat-sealing tool. The joining operation can be easily performed. Moreover, since the end faces of the resin tube are fused to both sides of the sheet-like base material of the heat-sealing tool disposed between the end portions of the resin pipe, the joint portion of the resin pipe has high sealing properties and high bonding strength. Become.

  In the invention of claim 2, the heating wire is wound around the heating wire fixing notches formed at a plurality of locations on the inner peripheral edge and the outer peripheral edge of the sheet-like substrate, and the heating wire is wound around the sheet-like substrate. Can prevent misalignment of heating wire wound around the material and short circuit caused by short-circuiting and energizing, can exhibit constant fusion performance without variation, and sealability and bonding strength at the joint of resin pipe Can be further enhanced.

  In the invention of claim 3, since the sheet-like base material is made of a heat-meltable material, the end of the resin tube that is in contact with the heat-sealing tool by energizing the heating wire wound around the sheet-like base material Part is heated and fused to the sheet-like base material, and the sheet-like base material is melted, and the ends of the resin tube are fused to each other through the melted sheet-like base material. Bonding strength can be obtained.

  In the invention of claim 4, since the inner peripheral edge and the outer peripheral edge of the sheet-like base material are divided by the dividing portion, and the inside and the outside of the heat-sealing tool are communicated through the dividing portion, the resin pipe to be joined is piped In the case of an annular covering material attached to the outer periphery of the pipe, the pipe is inserted from the split part of the sheet-like base material into the center in the sheet-like base material, that is, in the center of the heat fusion tool, and heat is applied to the outer periphery of the pipe. A welding tool can be fitted, and a thermal welding tool can be easily arranged between the ends of a coating material (resin pipe) on the outer periphery of the pipe.

  In the invention of claim 5, since the annular sheet-like cover material made of an electrically insulating material is bonded to both surfaces of the sheet-like substrate around which the heating wire is wound, the electric wire wound around the sheet-like substrate is used. It is possible to protect the heat ray and prevent the heat ray from being damaged by contacting the resin tube or the surrounding structure when the heat-sealing tool is disposed between the ends of the resin tube. Therefore, joining work in a high place or a narrow place becomes easier.

  In the invention of claim 6, the inner peripheral edge positioning portion in which the flange of the inner peripheral edge of the sheet-like cover material is fitted to the inner peripheral edge of the end portion of the resin pipe when the heat fusion tool is disposed between the end portions of the resin pipe. On the other hand, since the flange on the outer peripheral edge of the sheet-like cover material becomes an outer peripheral edge positioning portion that fits to the outer peripheral edge of the end portion of the resin tube, the positioning of the heat-sealing tool with respect to the end portion of the resin tube is facilitated and You will be able to do it accurately.

  In the invention of claim 7, since the inner peripheral edge and the outer peripheral edge of the sheet-like base material and the sheet-like cover material are divided by the dividing portion, and the inside and the outside of the heat-sealing tool are communicated through the dividing portion. When the resin pipe to be used is an annular covering material attached to the outer periphery of the pipe, the pipe is connected to the center of the sheet-like base material and the sheet-like cover material from the divided part of the sheet-like base material and the sheet-like cover material, that is, heat fusion. It can be inserted into the center of the fitting, and the heat fusion tool can be fitted to the outer periphery of the pipe, and the heat fusion tool can be easily arranged between the ends of the coating material (resin pipe) on the outer circumference of the pipe. .

  In invention of Claim 8, since a sheet-like base material and a sheet-like cover material consist of a material which can be heat-melted, it contacts with a heat-fusion tool by supplying with electricity to the heating wire wound around the sheet-like base material. The ends of the resin tubes are thermally fused to the sheet-like cover material, and the ends of the resin tubes are fused by melting the sheet-like base material and the sheet-like cover material. Can be obtained.

It is a front view of the heat sealing | fusion tool which concerns on 1st Embodiment of this invention. It is a front view of the sheet-like base material used for the heat sealing | fusion tool of 1st Embodiment. It is a front view of the heat sealing | fusion tool which concerns on 2nd Embodiment of this invention. It is a disassembled perspective view of the heat sealing | fusion tool which concerns on 2nd Embodiment. It is a perspective view of the heat sealing | fusion tool which concerns on 3rd Embodiment of this invention. It is a disassembled perspective view of the heat sealing | fusion tool which concerns on 3rd Embodiment. It is a perspective view at the time of arrange | positioning the heat sealing | fusion tool of 2nd Embodiment between the edge parts of a resin pipe. It is a perspective view at the time of arrange | positioning the heat sealing | fusion tool of 3rd Embodiment between the edge parts of a resin pipe.

  The heat sealing | fusion tool 10 of 1st Embodiment shown in FIG. 1 is demonstrated. The heat-sealing tool 10 is for joining the end portions of a resin tube, and includes a sheet-like base material 11 and a heating wire 25 wound around the sheet-like base material 11. The resin pipe joined by the heat fusion tool 10 is a tubular covering material attached to the outer periphery of the piping or a piping itself without a covering material. The material constituting the resin pipe (the covering material or the pipe itself) is a material that can be heat-sealed. Examples of materials that can be heat-sealed include synthetic resins such as polyethylene, polybutene, and polyurethane. In addition, when joining the tubular coating | covering material with which the outer periphery of piping was joined, metallic things, such as copper and iron, may be sufficient as the said piping.

  The sheet-like base material 11 is made of an electrically insulating material and has an annular shape as shown in FIG. Examples of the electrically insulating material include a synthetic resin or a ceramic mica (mica) plate capable of heat-sealing the ends of the resin pipe to be joined. Furthermore, a more preferable material for the sheet-like substrate 11 is an electrically insulating material that can be melted by heat. If the sheet-like base material 11 is made of an electrically insulating material that can be melted by heat, the sheet-like base material 11 is used when the ends of the resin pipe are heat-sealed by energizing the heating wire 25 as will be described later. Can be melted by the heat generated by the heating wire 25, the end portion of the resin tube can be heat-sealed more reliably, and the bonding strength and sealing performance of the end portion of the resin tube can be further enhanced.

  Examples of the electrically insulating material that can be melted by heat include polyolefins such as polyethylene, and thermoplastic synthetic resins such as polyester and polyamide. Polyolefin is excellent in heat melting property, and polyester, polyamide and the like are excellent in heat sealing property. Examples of the polyolefin include polyethylene (melting point: 110 to 140 ° C.) and polypropylene (melting point: 130 to 160 ° C.). In particular, polyethylene is a preferable material for the sheet-like substrate 11 in that it has a low melting point, is easily melted by heat, and provides high fusion strength. The annular shape of the sheet-like substrate 11 is an annular shape having the same size as the end face of the resin pipe to be joined. Moreover, the thickness of the said sheet-like base material 11 is made into the thickness which can hold | maintain the shape of the said heat sealing | fusion tool 10, and mentions the thickness of about 0.2-5 mm as an example.

  On the inner peripheral edge 12 and the outer peripheral edge 15 of the sheet-like substrate 11, heating wire fixing notches 13 are formed at a plurality of positions having a predetermined interval. The heating wire fixing notch 13 has a concave shape, a V shape, a cut or the like into which the heating wire 25 can be fitted, so that the heating wire 25 can be correctly wound around the sheet-like base material 11, A position shift of the heating wire 25 after winding and a short circuit due to short circuit energization are prevented, and heating of the end portion of the resin tube can be stably and satisfactorily performed. The sheet-like base material 11 has holes 17 and 18 through which the vicinity of the end of the heating wire 25 passes.

  Further, the sheet-like base material 11 is formed with a dividing portion 19 that divides between the inner peripheral edge 12 and the outer peripheral edge 15 and passes through the inside and the outside of the heat-sealing tool 10. The said parting part 19 can be expanded by the deformation | transformation which twists the both sides of this parting part 19, and it is made to expand when arrange | positioning the heat-fusion tool 10 between the edge parts of the coating | covering material with which the outer periphery of piping was mounted | worn. By inserting the pipe into the center of the inner portion of the heat-sealing tool 10 through the dividing portion 19, the heat-sealing tool 10 can be easily disposed between the ends of the covering material on the outer periphery of the pipe.

  The heating wire 25 only needs to generate heat when energized, and is composed of a nichrome wire or the like. The heating wire 25 is not limited to a circular cross section, and may be a quadrangular or triangular shape. The heating wire 25 is selected to generate a heat generation amount capable of fusing the end of the resin tube. Both ends of the heating wire 25 are connection portions 27 and 28 with a power source. In addition, the said heating wire 25 is wound around the said sheet-like base material 11 avoiding the parting part 19 of the said sheet-like base material 11. FIG.

  3 and 4 show a thermal fusion tool 10A of the second embodiment. In the second embodiment, the same members as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment. In the heat-sealing tool 10A of the second embodiment, sheet-like cover materials 31A and 31A are bonded to both surfaces of the sheet-like base material 11 around which the heating wire 25 is wound. The sheet-shaped cover materials 31 </ b> A and 31 </ b> A have an annular shape and have an inner diameter and an outer diameter that can cover the sheet-shaped substrate 11. Further, the sheet-like cover materials 31A and 31A have dividing portions 34A and 34A that divide between the inner peripheral edge 32A and the outer peripheral edge 35A and pass through the inside and outside of the sheet-like cover materials 31A and 31A. It is formed at the same position as the dividing portion 19. The inside and outside of the heat-sealing tool 10 </ b> A are communicated by the divided portions 34 </ b> A and 34 </ b> A of the sheet-like cover materials 31 </ b> A and 31 </ b> A and the divided portion 19 of the sheet-like base material 11. Further, the divided portions 34A and 34A of the sheet-like cover materials 31A and 31A and the divided portion 19 of the sheet-like base material 11 can be expanded by deformation that twists both sides of the divided portions 34A, 34A and 19, and piping. When the heat-sealing tool 10A is disposed between the ends of the covering material attached to the outer periphery of the pipe, the pipe is heat-sealed from the outside of the heat-sealing tool 10A through the divided portions 34A, 34A, 19 which are expanded. By inserting it in the center of the interior of the tool 10A, the heat-sealing tool 10A can be arranged between the ends of the coating material on the outer periphery of the pipe.

  The sheet-like cover materials 31A and 31A are made of an electrically insulating material. Examples of the electrically insulating material constituting the sheet-like cover materials 31A and 31A include synthetic resin or ceramic capable of heat-sealing the end of the resin tube. Further, a more preferable material of the sheet-like cover materials 31A and 31A is an electrically insulating material that can be melted by heat. If the sheet-like cover materials 31A and 31A are made of an electrically insulating material that can be thermally melted, the sheet-like cover material 31A, when the end of the resin pipe is heat-sealed by energizing the heating wire 25, 31A can be melted by the heat generated by the heating wire 25, and the resin pipe can be heat-sealed more reliably, and the bonding strength and sealing performance at the end of the resin pipe can be further enhanced. Further, when the sheet-like base material 11 is made of an electrically insulating material capable of being thermally melted together with the sheet-like cover materials 31A and 31A, when the heating wire 25 is energized and the ends of the resin tubes are heat-sealed. Further, since the sheet-like cover materials 31A and 31A are melted together with the sheet-like base material 11, the end portion of the resin tube can be more reliably heat-sealed, and the bonding strength and the seal of the end portion of the resin tube can be more reliably performed. The sex can be further enhanced.

  Examples of the heat-meltable electrically insulating material constituting the sheet-shaped cover materials 31A and 31A include, like the sheet-shaped base material 11, polyolefins such as polyethylene, thermoplastic synthetic resins such as polyester and polyamide. Can do. Polyolefin is excellent in heat melting property, and polyester, polyamide and the like are excellent in heat sealing property. Examples of the polyolefin include polyethylene (melting point: 110 to 140 ° C.) and polypropylene (melting point: 130 to 160 ° C.). In particular, polyethylene is preferable in that it has a low melting point, is easily melted by heat, and high fusion strength can be obtained. The thicknesses of the sheet-like cover materials 31A and 31A are determined as appropriate, and are about 0.1 to 2 mm as an example. The adhesion of the sheet-like cover materials 31A and 31A to the sheet-like base material 11 is not limited to the adhesive, and the sheet-like cover materials 31A and 31A are provided on both surfaces of the sheet-like base material 11 around which the heating wire 25 is wound. The sheet-like base material 11 on which the heating wire 25 is wound is laminated and heat-pressed and laminated, and the mold for injection molding in which the cavities for the sheet-like cover materials 31A and 31A are formed. The sheet-like cover materials 31A and 31A may be injection-molded on both surfaces of the sheet-like substrate 11 by injecting resin into the cavity.

  5 and 6 show a thermal fusion tool 10B of the third embodiment. In the third embodiment, the same members as those in the first and second embodiments are denoted by the same reference numerals as those in the first and second embodiments. The heat-sealing tool 10B according to the third embodiment replaces the sheet-like cover materials 31A and 31A in the second embodiment with both sides of the sheet-like base material 11 around which the heating wire 25 is wound, instead of the sheet-like cover materials 31B and 31B. The second embodiment is different from the second embodiment in that it is adhered to the second embodiment, and other configurations are the same as those of the second embodiment.

  The sheet-like cover materials 31B and 31B in the third embodiment are such that flanges 36B, 36B, 37B, and 37B protruding outward are formed on both the inner peripheral edges 32B and 32B and the outer peripheral edges 35B and 35B. Unlike the sheet-like cover materials 31A and 31A in the second embodiment, other configurations are the same as the sheet-like cover materials 31A and 31A in the second embodiment. Reference numerals 34B and 34B are dividing portions for dividing the inner peripheral edges 32B and 32B of the sheet-shaped cover materials 31B and 31B and the outer peripheral edges 35B and 35B, and are located at the same positions as the dividing portions 19 of the sheet-like base material 11. Is formed. Further, the flanges 36B, 36B, 37B, 37B are not formed at positions corresponding to the divided portions 34B, 34B on the inner peripheral edges 32B, 32B and the outer peripheral edges 35B, 35B.

  The flanges 36B and 36B on the inner peripheral edge are fitted into the inner peripheral edge of the end portion of the resin tube when the heat-welding tool 10B is disposed between the end portions of the resin tube to join the end portions of the resin tube. On the other hand, the flanges 37B and 37B on the outer peripheral edge serve as outer peripheral edge positioning parts that fit on the outer peripheral edge of the end portion of the resin tube. The presence of the inner peripheral flanges 36B and 36B and the outer peripheral flanges 37B and 37B facilitates correct placement of the heat-sealing tool 10B between the ends of the resin pipe. The end of the resin tube is fitted between the flanges 36B and 36B on the inner peripheral edge and the flanges 37B and 37B on the outer peripheral edge. The heights of the flanges 36B and 36B on the inner peripheral edge and the flanges 37B and 37B on the outer peripheral edge are determined as appropriate, for example, about 3 mm to 10 mm. In the illustrated third embodiment, the sheet-like cover materials 31B and 31B are formed with the flange on both the inner and outer peripheral edges, but only on either the inner or outer peripheral edge. May be formed. In addition, the sheet-like cover materials 31B and 31B are bonded to both surfaces of the sheet-like base material 11 around which the heating wire 25 is wound with an adhesive. Sheet-like cover materials 31B and 31B are laminated on both sides and fused by hot pressing, or the sheet-like base material 11 around which the heating wire 25 is wound is formed with a cavity for the sheet-like cover materials 31B and 31B. It may be performed by setting in an injection mold that has been performed, injecting resin into the cavity, and injection-molding the sheet-like cover materials 31B and 31B on both surfaces of the sheet-like base material 11.

  The joining method of the resin pipe end part using the heat sealing | fusion tool of the said 1st-3rd embodiment is demonstrated. The joining using the heat-sealing tool 10 of the first embodiment and the joining using the heat-sealing tool 10A of the second embodiment are the same except that the heat-sealing tool used is different. Therefore, in the following description, the case of using the thermal fusion tool 10A of the second embodiment will be described as an example.

  FIG. 7 shows a case where the heat-sealing tool 10 </ b> A of the second embodiment is disposed between the end portions 72 and 74 of the tubular covering materials 71 and 73 attached to the outer circumferences of the pipes 61 and 63. In the case of the illustration, the end portion 62 of one pipe 61 is inserted into the end portion 64 of the other pipe 63 whose diameter is increased, whereby the end portion 52 of the pipe 61 and the end portion 64 of the pipe 63 are connected. Yes. The covering materials 71 and 73 are attached to the outer surface of the pipes 61 and 63 so as to be slidable along the length direction of the pipes. The connecting portion 67 of the pipes 61 and 63 is not covered with the covering materials 71 and 73 but is exposed between the opposing end portions 72 and 74 of the covering materials 71 and 73. The covering materials 71 and 73 are made of a heat-sealable material such as polyethylene.

  First, the thermal fusion tool 10 </ b> A is disposed on the pipe connection portion 67 exposed between the end portions 72 and 74 of the covering material. At that time, the divided portions 19 and 34A are expanded by, for example, twisting both sides of the divided portions 19 and 34A of the heat-sealing tool 10A, and the portions of the divided portions 19 and 34A are connected to the pipe connecting portions 67. Is inserted into the heat-sealing tool 10A. Next, the covering materials 72 and 74 are slid to bring the end portions 72 and 74 of the covering material into contact with both surfaces of the fusion tool 10A. And it supplies with electricity to the heating wire 25 with the power supply (not shown) connected to the connection parts 27 and 28 of the both ends of the heating wire 25 of the said heat sealing | fusion tool 10A. The heating wire 25 generates heat due to the energization and heats and melts the end portions 72 and 74 of the covering material in contact with the heat fusion tool 10A, and the covering material ends 72 and 74 are passed through the heat fusion tool 10A. Is heat-sealed. When the sheet-like base material 11 and the sheet-like cover material 31A are made of a heat-meltable material, the sheet-like base material 11 and the sheet-like cover material 31A are melted by the heat generated by the heating wire 25 due to the energization. Therefore, the joining between the end portions of the covering material through the heat fusion tool 10A becomes more reliable, and the sealing property and strength of the joining portion are high.

  FIG. 8 shows a case where the thermal fusion tool 10B of the third embodiment is disposed between the end portions 82 and 84 of the resin pipes 81 and 83. FIG. The resin pipes 81 and 83 are made of a heat-sealable material such as polyethylene. First, the thermal fusion tool 10B is disposed between the end portions 82 and 84 of the resin pipes 81 and 83, and the end portions 82 and 84 of the resin pipe are brought into contact with both surfaces of the thermal fusion tool 10B. At that time, by inserting the end portions 82 and 84 of the resin tube between the flange 36B on the inner peripheral edge and the flange 37B on the outer peripheral edge formed on both surfaces of the heat-sealing tool 10B, The inner peripheral flange 36B is fitted to the inner peripheral edge of the end portions 82, 84, and the outer peripheral flange 37B is fitted to the outer peripheral edge of the end portions 82, 84 of the resin tube. The tool 10B can be easily placed at the correct position between the ends 82 and 84 of the resin tube. Thereafter, the heating wire 25 is energized by a power source (not shown) connected to the connecting portions 27 and 28 at both ends of the heating wire 25 of the heat-sealing tool 10B. Due to the energization, the heating wire 25 generates heat to heat and melt the end portions 82 and 84 of the resin tube that are in contact with the heat-sealing tool 10B, and the end portion of the resin tube via the heat-sealing tool 10B. Is heat-sealed. Further, when the sheet-like base material 11 and the sheet-like cover material 31B are made of a heat-meltable material, the sheet-like base material 11 and the sheet-like cover material 31B are melted by the heat generated by the heating wire 25 due to the energization. Therefore, the joining between the end portions of the resin pipe via the thermal fusion tool 10B becomes more reliable, and the sealing performance and strength of the joining portion are high.

  In addition, when joining the edge part of the resin pipe | tube (for example, resin pipes 81 and 83 shown in FIG. 8) of piping itself with no coating | covering material instead of the coating | covering material of piping with the heat sealing | fusion tool of this invention, said 1st -It is good also as a structure which does not provide the parting part 19,34A, 34B in the heat sealing | fusion tool 10,10A, 10B of 3rd Embodiment.

  In order to investigate the sealing performance and bonding strength of the joint when the ends of the resin pipe (covering material and piping) were joined using the heat-sealing tool of the present invention, the following heat-sealing tool was prepared.

-1st Example (heat-fusion tool for coating | covering materials)
First, a heat fusion tool for a covering material is prepared. A high-density polyethylene sheet (thickness 0.3 mm) is punched into an annular shape having an inner diameter of 35.0 mm and an outer diameter of 72.0 mm, and notches are formed in the inner and outer peripheral edges at intervals of a central angle of 10 degrees. A shaped substrate was formed. A heating wire was wound around a portion between the inner peripheral edge and the outer peripheral edge of the sheet-like base material while a heating wire (nichrome wire, 20 Ω / m) was fitted into the notch. The overall resistance value of the wound heating wire was 22.7Ω, and the length of the heating wire was about 1130 mm. Next, a polyethylene sheet (thickness 0.2 mm) larger than the sheet-like base material is laminated on both sides of the sheet-like base material wound with a heating wire, and hot-pressed, whereby the polyethylene sheet is provided on both sides of the sheet-like base material. Was fused and pasted. Thereafter, the polyethylene sheet on both sides of the sheet-like base material was cut at an inner diameter of 30 mm and an outer diameter of 75 mm, and an excess portion was cut off, and the sheet-like cover material was adhered to both sides of the sheet-like base material around which the heating wire was wound. A heat fusion tool was created.

  The heat-sealing tool thus created is the end of a heat-insulating tube of an air-conditioning coated copper tube (a copper tube has an outer diameter of 31.75 mm and a heat insulating material (coating material) is a 20 mm thick polyethylene foam heat insulating material). The both ends of the heating wire of the heat fusion tool were connected to the power supply device, and a constant current of 1.80 A was passed through the heating wire. At that time, the voltage was about 41 V and the power was 74 W. After energizing for about 20 seconds, it was maintained for about 30 seconds for cooling. After cooling, the connection between the heating wire and the power supply device was disconnected to complete the joining.

When the joining strength was examined with respect to the joined portion of the heat insulating material made of polyethylene foam joined in this manner, a high joining force could be confirmed. It should be noted that the bonding strength (tensile strength) of the heat insulating material joint is the tensile strength of JIS A 9511 (foamed plastic heat insulating material) with respect to a test piece having a width of 10 mm and a thickness of 20 mm punched from the heat insulating material joint. The bonding strength was measured by an autograph according to the test. The test conditions are a tensile speed of 500 mm / min and a test temperature of 23 ° C. The measurement result of tensile strength (bonding strength) was 20 N / cm ² .

Second embodiment (Pipe heat fusion tool)
In place of the heat-insulating material (coating material) of the polyethylene foam, the sealing property and the bonding strength of the bonding portion were also examined for the polyethylene pipe (piping) which is the piping itself.
First, a heat fusion tool for piping was prepared. A polyethylene sheet (thickness: 0.3 mm) is punched into an annular shape having an inner diameter of 35.0 mm and an outer diameter of 41.0 mm, and notches are formed in the inner and outer peripheral edges at intervals of a central angle of 9 degrees to form an annular sheet-like base A material was formed. Similarly to the above, a heating wire (nichrome wire, 20 Ω / m) was wound around the notch. The overall resistance value of the wound heating wire was 4.4Ω, and the length of the heating wire was about 222 mm. Next, a polyethylene sheet (thickness 0.2 mm) was laminated on both sides of the sheet-like base material around which the heating wire was wound, and was bonded by hot pressing. Thereafter, the polyethylene sheet on both sides of the sheet-like base material was cut with an inner diameter of 30 mm and an outer diameter of 42 mm, and an excess portion was cut off, and the sheet-like cover material was adhered to both sides of the sheet-like base material on which the heating wire was wound. A heat fusion tool was created.

  The heat fusion tool thus created was sandwiched between the ends of a polyethylene pipe (two-layer pipe for water supply, nominal diameter 30 A), and a constant current of 1.80 A was passed through the heating wire. The voltage at that time was about 8V, and the power was 14.4W. After energizing for about 20 seconds, it was maintained for about 30 seconds for cooling. After cooling, the connection between the heating wire and the power supply device was disconnected to complete the joining.

  When the sealing property (air tightness, water tightness) and joining strength of the joined part of the polyethylene pipe joined in this way were examined, it was confirmed that the air tightness and water tightness as well as high joining property were good. In addition, the airtight test and the watertight test were performed according to JIS K 6770 (crosslinked polyethylene pipe joint). In other words, in the airtight test, both ends of the joint part of the polyethylene pipe are sealed, a pressure of 0.6 MPa is applied to the inside with air at normal temperature (23 ° C.), the holding time is set to 2 minutes, and leakage and other defects are visually observed. Investigated by. The watertight test was performed by joining a polyethylene pipe with a length of 250 mm at both ends so as to be 500 mm at both ends. However, the water pressure was 0.02 MPa, the test time was 2 minutes, and leakage and other defects were examined visually. The bonding strength was determined according to JIS K 6762 (polyethylene double-layer pipe for water supply). That is, a test piece was prepared so that the joint was at the center, and measured by an autograph at a tensile rate of 200 mm / min and a test temperature of 23 ° C. The value of the measurement result was a tensile yield strength of 19.6 MPa or more.

DESCRIPTION OF SYMBOLS 10, 10A, 10B Thermal fusion tool 11 Sheet-like base material 13 Notch 19 Dividing part of sheet-like base material 25 Heating wire 31A, 31B Sheet-like cover material 34A, 34B Dividing part of sheet-like cover material 36B Flange of inner peripheral edge 37B Outer peripheral flange

Claims (8)

  An annular sheet-like base material made of an electrically insulating material in a heat sealing tool for a resin tube, which is disposed between the end portions of the resin tube and thermally bonded by joining the ends of the resin tube. A heat-sealing tool for a resin tube, wherein a heating wire is wound around a portion between an inner peripheral edge and an outer peripheral edge, and both ends of the heating wire are connected to a power source.   Heating wire fixing cutouts are formed at a plurality of locations on the inner peripheral edge and outer peripheral edge of the sheet-like substrate, and the heating wires are wound around the sheet-like substrate by fitting into the heating wire fixing cutouts. The heat sealing tool for a resin pipe according to claim 1, wherein   The said pipe-shaped base material consists of a material which can be heat-melted, The heat-fusion tool of the resin pipe | tube of Claim 1 or 2 characterized by the above-mentioned.   Either of the inner periphery and the outer periphery of the said sheet | seat base material is divided | segmented, The part to which the inside and the outer side of the said heat-fusion tool pass is formed in the said sheet | seat base material, The any one of Claim 1 to 3 characterized by the above-mentioned. The heat-fusion tool for resin pipes according to one item.   The heat of the resin tube according to claim 1 or 2, wherein an annular sheet-like cover material made of an electrically insulating material is bonded to both surfaces of the sheet-like substrate around which the heating wire is wound. Fusion tool.   A flange projecting outward is formed on one or both of the inner peripheral edge and the outer peripheral edge of the sheet-like cover material, and the flange of the inner peripheral edge is fitted to the inner peripheral edge of the end portion of the resin tube. 6. The resin pipe heat fusion tool according to claim 5, wherein the outer peripheral flange is an outer peripheral positioning part that fits into an outer peripheral edge of the end of the resin pipe. 7. .   The sheet-like base material and the sheet-like cover material are divided between the inner peripheral edge and the outer peripheral edge, and a dividing portion is formed in the sheet-like base material and the sheet-like cover material through the inside and outside of the heat-sealing tool. The heat-sealing tool for a resin pipe according to claim 5 or 6,   8. The resin pipe heat-sealing device according to claim 5, wherein the sheet-like base material and the sheet-like cover material are made of a heat-meltable material.

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