JP6203042B2 - Branch joint - Google Patents

Description

  The present invention relates to a branch joint that connects a main pipe and a sub pipe.

  When connecting the main pipe and the sub pipe, a branch joint is generally used. For example, in a branch joint, an opening is formed in a main pipe, a branch joint is attached to the opening, and a sub pipe through which drainage flows to the main pipe or a sub pipe through which drainage from the main pipe flows. Connect the tubes.

  For example, Patent Literature 1 discloses that an opening is formed in a main pipe using a tool such as a hole saw, a branch joint is fixed to the opening, and a secondary pipe is connected. Further, in Patent Document 2, an opening for connecting a branch joint with a hole saw or the like is drilled in the main pipe (connected pipe), the branch joint is inserted into the opening from the outside of the main pipe, and the nut body is attached to the main pipe. There is a disclosure in which a branch joint is fixed to a main pipe by tightening and screwing from the outside. In Patent Document 3, a pipe wall of a main pipe (tubular body) is drilled to form an opening, a branch joint is inserted from the outside of the main pipe, and a nut is tightened from the inside of the main pipe to branch the joint. Is disclosed to be fixed to the main pipe.

Japanese Patent Application Laid-Open No. 06-207697 JP 2002-228076 A JP2012-082876A

  In order to attach the branch joint, the main pipe is generally opened using a tool such as a hole saw. There is a problem that the size of the opening varies depending on the skill level of the operator who performs the drilling operation and the performance of a tool such as a hole saw. If the opening is not drilled with high dimensional accuracy, the fixability and water stoppage of the branch joint will deteriorate. For this reason, it is desirable for the branch joint to ensure water-stopping and fixing properties even when there are variations in the size of the opening.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a branch joint that can ensure water-stopping and fixing properties even when the dimensional accuracy of the hole to be drilled in the main pipe is poor. To do.

  In order to solve the above-mentioned object, the branch joint of the present invention is a branch joint that is attached to an opening drilled in the main pipe and connects the sub pipe to form a branch path, and the sub pipe can be connected to the branch joint. A cylindrical member inserted into the opening of the main pipe from the outside, and a hole through which the cylindrical member is inserted, arranged between the locking surface formed on the outer periphery of the cylindrical member and the main pipe, A flange member that covers the periphery of the opening from the outside, and an inclined portion that contacts the edge of the opening from the inside of the main pipe, and is screwed into the cylindrical member from the inside of the main pipe, and the inclined portion and the engagement member And a fixing member that sandwiches the main pipe via the flange member between the retaining surface and the stop surface.

  According to the present invention, the branch joint can be accurately attached to the opening formed in the main pipe.

It is a conceptual diagram of the latent heat recovery type gas water heater which adapts the branch joint by this embodiment. Sectional drawing of the branch joint of 1st Embodiment of this invention is shown, FIG. 2 (A) is the state attached to the main pipe, FIG. 2 (B) is an exploded state. It is a perspective view of the cylindrical member of a branch joint. It is a perspective view of the state which combined packing with the collar member of a branch joint. It is a perspective view of the fixing member of a branch joint. FIG. 6 (A) shows a state of forming a hole in the main pipe by a hole saw, FIG. 6 (B) shows a state of the main pipe provided with the hole, FIG. 6 (C) shows a state in which the cylindrical member is inserted into the opening covered with the flange member, and FIG. 6 (D) shows a state in which the cylindrical member, the flange member, and the fixing member are attached to the opening. FIG. 6E shows a state where a secondary pipe is further attached. FIG. 7A is an explanatory view of a case where a branch joint is attached to a 35 mm diameter opening provided in a main pipe having an outer diameter of 165 mm (first application example), FIG. 7A shows a cross-sectional view of the branch joint, and FIG. It is a projection figure of an opening. FIG. 8A is an explanatory diagram of a case where a branch joint is attached to a 38 mm diameter opening provided in a main pipe having an outer diameter of 165 mm (second application example), FIG. 8A shows a cross-sectional view of the branch joint, and FIG. It is a projection figure of an opening. FIG. 9A is an explanatory view of a case where a branch joint is attached to a 40 mm diameter opening provided in a main pipe having an outer diameter of 165 mm (third application example), FIG. 9A shows a sectional view of the branch joint, and FIG. It is a projection figure of an opening. FIG. 10A is an explanatory diagram of a case where a branch joint is attached to a 35 mm diameter opening provided in a main pipe having an outer diameter of 216 mm (fourth application example), FIG. 10A shows a cross-sectional view of the branch joint, and FIG. It is a projection figure of an opening. FIG. 11A is an explanatory view of a case where a branch joint is attached to a 38 mm diameter opening provided in a main pipe having an outer diameter of 216 mm (fifth application example), FIG. 11A shows a sectional view of the branch joint, and FIG. It is a projection figure of an opening. FIG. 12A is an explanatory view of a case where a branch joint is attached to a 40 mm diameter opening provided in a main pipe having an outer diameter of 216 mm (sixth application example), FIG. 12A shows a cross-sectional view of the branch joint, and FIG. It is a projection figure of an opening. It is sectional drawing which adapts the saddle member from which a curvature radius differs with respect to the main pipe which has a predetermined outer diameter, and FIG. 13 (A)-(C) shows the case where the saddle member from which a curvature radius differs is applied, respectively. It is sectional drawing of the branch joint of 2nd Embodiment of this invention, FIG. 14 (A) shows the state which attached the branch joint to the main pipe, FIG.14 (B) fits a cylindrical member and a saddle member. The part to be enlarged is shown.

<< First Embodiment >>
A first embodiment as an example of an embodiment to which the present invention is applied (hereinafter, this embodiment) will be described in detail with reference to the drawings. The technical scope of the present invention is not limited to this embodiment. The present embodiment can be variously modified without departing from the spirit of the present invention.

FIG. 1 is a conceptual diagram in which the branch joint 30 of the first embodiment is applied to the latent heat recovery type gas water heater 1. A latent heat recovery type gas water heater 1 shown in FIG. 1 is a hot water heater whose hot water heat efficiency is improved by recovering the latent heat of combustion gas. This latent heat recovery type gas water heater 1 can improve the hot water supply heat efficiency in a conventional water heater from about 80% to about 95%. As a result, energy saving can be realized, and the running cost can be greatly reduced. The amount of carbon dioxide (CO ₂ ) emissions can be reduced by about 13% compared to the conventional type, thereby reducing the global environmental load and operation costs.

Inside the water heater main body 2 of the latent heat recovery type gas water heater 1, a water supply pipe 3 for introducing water into the heat exchange path 4, and heat exchange for heating the water introduced from the water supply pipe 3 by the heat exchanger 6. The hot water heated by the path 4 and the heat exchange path 4 is connected to a hot water supply pipe line 5 for supplying equipment such as a bath.
The heat exchanger 6 includes a primary heat exchange unit 11 and a secondary heat exchange unit 12. Hot water supplied from the water supply pipe 3 and flowing through the heat exchange path 4 passes through the secondary heat exchange part 12 and then passes through the primary heat exchange part 11 and is introduced into the hot water supply pipe 5.

  The heat exchanger 6 includes a fuel supply line 7 for supplying a gas as a fuel, a combustion unit 8 for burning the fuel, a heat exchanger 9 for heating the heat exchange channel 4 with heat generated in the combustion unit 8, It is comprised with the ventilation part 10 which sends heat to the heat exchanger 9. FIG. The heat generated in the combustion unit 8 heats the water in the heat exchange path 4 by the primary heat exchange unit 11 of the heat exchanger 6 by blowing from the blower unit 10. Further, the residual heat of the primary heat exchange unit 11 heats the low temperature water led from the water supply pipe 3 by the secondary heat exchange unit 12 of the heat exchanger 6. As described above, the latent heat recovery type gas water heater 1 efficiently uses the heat generated in the combustion unit 8.

  The heat exchanger 6 of the latent heat recovery type gas water heater 1 performs heat exchange to lower the temperature of the combustion gas instead of increasing the temperature of the water in the heat exchange path 4 by the heat generated in the combustion unit 8. When the temperature of the combustion gas decreases due to this heat exchange, drain 16 that is condensed water is generated from the combustion gas. In the latent heat recovery type gas water heater 1, the drain 16 is recovered by the drain recovery unit 17.

  The drain 16 dissolves acidic components such as nitrogen oxide (NOX) contained in a minute amount in the combustion gas. The drain 16 in which an acidic component is dissolved in the combustion gas exhibits an acidity of about pH 3, for example. That is, the drain 16 shows strong acidity. For this reason, the drain 16 cannot be discharged to the outside at the pH value as it is. Therefore, the latent heat recovery type gas water heater 1 includes a neutralizer 19 in the middle of the drain discharge pipe 18 connected downstream of the drain recovery unit 17.

The neutralizer 19 neutralizes the pH value of the drain 16 to neutrality of about pH 7. Neutralization by the neutralizer 19 is based on the action of a neutralizer filled in the neutralizer 19. As the neutralizing agent, for example, calcium carbonate (CaCO ₃ ) used for general neutralization treatment can be used. The neutralizer 19 neutralizes the acidic drain 16 neutrally by the action of the neutralizing agent.

  The amount of drain 16 generated is proportional to the amount of combustion gas. For this reason, as for the filling amount of the neutralizing agent, the amount necessary for the treatment of the drainage generated during the standard use period of the latent heat recovery type gas water heater 1 is calculated in advance, and the necessary amount is neutralized. 19 In the latent heat recovery type gas water heater 1, the drain 16 is neutralized by the neutralizer 19 and discharged from the drain discharge pipe 18 to the drain branch 20 outside the water heater main body 2.

  Note that the drain discharge pipe 18 protruding from the water heater body 2 and the drainage branch pipe 20 are not directly connected. A gap that opens to the atmosphere is provided between the drain discharge pipe 18 and the drainage branch pipe 20 for indirect drainage. The drain receiver 21 provided at the upper end of the drainage branch pipe 20 receives the drain 16 flowing from the drain discharge pipe line 18 and causes the drain 16 to flow into the drainage branch pipe 20. The drainage branch 20 is connected to a sewage mass 22 buried in the ground via a branch joint 30, for example. The sewage mass 22 includes a lid portion 23 that can be opened and closed from above. Then, the drain 16 flows to the downstream pipe 24 connected to the sewage mass 22.

  The reason for the indirect piping is that the sewage to the latent heat recovery type gas water heater 1 is returned when the sewage flows backward from the sewage mass 22 due to clogging of the drainage pipe 20, the sewage mass 22 or the downstream pipe 24. This is to prevent intrusion. The drainage branch 20 in FIG. 1 is not provided with a sealing mechanism for preventing odor diffusion, but a sealing mechanism can be provided in the drainage branch 20 according to the installation location where indirect piping is performed.

  FIG. 2A is an enlarged cross-sectional view of a branch joint 30 that connects the drainage branch pipe 20 and the sewage mass 22 (hereinafter, main pipe 22) shown in FIG. FIG. 2B shows an exploded state of the branch joint 30. As shown in FIGS. 2A and 2B, an opening 25 is provided in the main pipe 22, and a branch joint 30 is attached to the opening. Further, a drainage branch pipe 20 (hereinafter referred to as sub pipe 20) is attached to the branch joint 30 to constitute a branching structure.

The branch joint 30 includes a cylindrical tubular member 32, a flange member 33, and a fixing member 41. In the example shown in FIGS. 2A and 2B, a spacer 56 (packing 56) is interposed between the tubular member 32 and the flange member 33, and between the flange member 33 and the main pipe 22. This is an example in which a packing 36 is interposed.
In a state where the cylindrical member 32 is inserted into the opening 25 of the main pipe 22, the fixing member 41 can be screwed from the inner diameter side of the main pipe 22 through the flange member 33 and the packing 36. As a result, the cylindrical member 32 and the fixing member 41 are arranged with the spacer 56, the flange member 33, and the packing 36 interposed therebetween, and the branch joint 30 is attached to the opening 25 of the main pipe 22 by sandwiching the pipe wall of the main pipe 22. be able to.

An annular protrusion 88 is formed on the outer periphery of the cylindrical member 32, and the annular protrusion 88 divides the entire length of the cylindrical member 32 into an insertion cylinder part 32 a and an outer cylinder part 32 b.
The through hole 34 constituting the inner diameter of the cylindrical member 32 is provided with a step portion 35 that forms a step by narrowing the inner diameter of the cylindrical member 32 radially inward from the wall side of the through hole 34. The step portion 35 functions as positioning of the secondary tube 20 when the secondary tube 20 is inserted into the tubular member 32 from the outer cylindrical portion 32b side.
The step portion 35 is formed to have an inner diameter that does not hinder the flow of the drain 16 when the sub pipe 20 is inserted and connected to the cylindrical member 32. The step portion 35 is formed at, for example, the middle portion of the cylindrical member 32 in the longitudinal direction.

  FIG. 3 is a perspective view of the cylindrical member 32. The cylindrical member 32 is formed with a locking portion 37 (male thread) that engages with a fixing member 41 for fixing the branch joint 30 to the main pipe 22. The locking portion 37 according to the first embodiment is formed on the outer periphery of the insertion tube portion 32 a of the tubular member 32 in a screw shape protruding outward in the radial direction of the tubular member 32. The fixing member 41 engages with the locking portion 37 from the inside of the main pipe 22 to fix the branch joint 30 to the opening 25.

Moreover, the annular protrusion 88 formed on the outer periphery of the cylindrical member 32 has a larger diameter than the cylindrical member 32 and is formed integrally with the cylindrical member 32 so as to protrude radially outward. In the annular protrusion 88, the locking surface 88a formed on the insertion tube portion 32a side is a flat surface.
The locking surface 88 a of the annular protrusion 88 plays a role of locking the flange member 33 and pressing the flange member 33 against the outer periphery of the main pipe 22.
The shape and location of the annular protrusion 88 are not limited to those of this embodiment. For example, the annular protrusion 88 may be partially provided on the outer periphery of the tubular member 32. Further, in the cylindrical member 32, the outer cylindrical portion 32b may be formed with a larger diameter than the insertion cylindrical portion 32a, and a step may be provided at the boundary portion. In this case, the surface of the stepped portion on the side of the insertion tube portion 32 a functions as the locking surface 88 a, and the flange member 33 can be pressed against the outer periphery of the main tube 22. However, as exemplified in the present embodiment, the necessary material can be reduced by forming the annular projecting portion 88 that partially projects on the outer periphery of the cylindrical member 32.

  A plurality of guide portions 38 for guiding the branch joint 30 in the opening 25 are formed in the insertion tube portion 32 a of the tubular member 32. These guide portions 38 are integrally formed from the locking surface 88 a of the annular projecting portion 88 to the insertion tube portion 32 a of the tubular member 32. The plurality of guide portions 38 are formed in a rib shape along the axial direction (longitudinal direction) of the cylindrical member 32. The rib-shaped guide portion 38 of the first embodiment is provided between the annular protrusion 88 and the locking portion 37. The plurality of guide portions 38 are formed at, for example, eight locations at equal intervals. The number and shape of the rib-shaped guide portions 38 are not limited to the above. For example, the guide portion 38 may be formed over the entire circumference of the insertion tube portion 32a instead of the rib shape. The guide portion 38 is formed to be shorter than the thickness of the tube wall of the main pipe 22 along the axial direction (longitudinal direction) of the cylindrical member 32 and to maintain the same outer diameter, and the guide portion 38 is contracted along the axial direction. And a tapered portion 40 having a diameter.

  The same diameter part 39 of the guide part 38 of 1st Embodiment is formed in the dimension shorter than thickness 5.1mm of the pipe wall of the main pipe 22. FIG. The dimension of the same diameter part 39 of 1st Embodiment is 4.0 mm. The taper part 40 is reduced in diameter toward the terminal side with a wide dimension on the same diameter part 39 side. The taper portion 40 of the first embodiment is formed with an inclination of about 26 degrees (an inclination of 2.15 / 4.24). The tapered portion 40 smoothly guides the cylindrical member 32 into the opening 25 by the inclination.

  The inclination of the tapered portion 40 secures a gap where the guide portion 38 and a spherical surface portion 42 (inclined portion) of the fixing member 41 described later do not contact with each other in a state where the branch joint 30 is fixed to the main pipe 22. The inclination of the taper portion 40 may be other as long as a clearance where the guide portion 38 and the spherical surface portion 42 of the fixing member 41 do not contact each other can be secured. For example, the inclination of the taper portion 40 may be about 20 degrees to about 30 degrees.

As shown in FIG. 4, the flange member 33 is formed of a member different from the cylindrical member 32. 4 is provided with a packing 36 on a surface 33a on the side in contact with the main pipe 22. As shown in FIG.
The flange member 33 is formed in a shape that covers the opening 25 on the outer diameter of the cylindrical member 32 and abuts on the outer diameter of the main pipe 22. The outer shape of the collar member 33 is rectangular. In the center of the flange member 33, a hole 89 through which the insertion tube portion 32a of the tubular member 32 can be inserted is formed. Further, a flat portion 90 is formed around the hole 89 so as to protrude toward the annular protrusion 88 and to face the locking surface 88a. The flat portion 90 has a flat surface corresponding to the locking surface 88 a of the annular protrusion 88. The dimension of the flat part 90 is formed, for example, to the same outer diameter as the outer diameter of the annular projecting part 88.

  The locking surface 88a and the flat part 90 have a flat shape corresponding to each other. Therefore, the flat portion 90 of the flange member 33 can come into surface contact with the locking surface 88 a of the annular protrusion 88. Further, a spacer 56 (FIG. 2 (A) for adjusting the thickness error of the pipe wall of the main pipe 22 as necessary is provided between the locking surface 88a of the annular protrusion 88 and the flat part 90 of the flange member 33. ), (B))). For the spacer 56, a waterproof packing can be used in order to provide a function of improving the water-stopping property. When the spacer 56 is provided, the flat portion 90 and the locking surface 88 a face each other with the spacer 56 interposed therebetween, and the spacer 56 is sandwiched.

  Then, the flange member 33 is extrapolated from the insertion tube portion 32a side of the tubular member 32 to the locking surface 88a of the annular projecting portion 88, and is disposed between the locking surface 88a and the main tube 22 so as to form the opening 25. Cover the surroundings. Further, the flange member 33 is formed to be curved with a constant curvature so as to be substantially along the circumferential direction of the outer diameter of the locking main pipe 22. In addition, it is preferable that the curvature of the flange member 33 is set to a gentle diameter that is gentler than the outer diameter of the main pipe 22 from a curvature that is substantially the same as the outer diameter of the main pipe 22. A specific shape of the flange member 33 is a gentle diameter that is gentler than the curvature of the outer diameter of the main pipe 22, and is formed in a shape that substantially follows the circumferential direction of the outer diameter of the main pipe 22.

The cylindrical member 32 and the flange member 33 are formed of a synthetic resin such as a vinyl chloride resin, for example. In the vinyl chloride resin, various additives such as a plasticizer, a stabilizer, a filler, an ultraviolet absorber, an antioxidant, and a processing aid are appropriately blended with the vinyl chloride resin.
In addition to these vinyl chloride resins, synthetic resins copolymerize vinyl chloride monomers with other monomers and oligomers, such as ethylene-vinyl chloride copolymer resins, vinyl acetate-vinyl chloride copolymer resins, and urethane-vinyl chloride copolymer resins. It may be blended with other synthetic resins such as polyethylene resins, polypropylene resins, ethylene-vinyl acetate copolymer resins, acrylic resins, urethane resins, polyester resins, nitrile rubbers, acrylic rubbers, and synthetic rubbers. In addition to vinyl chloride resins, plasticizers, stabilizers, lubricants, fillers, ultraviolet absorbers, and other various additives can be added as appropriate to synthetic resins other than vinyl chloride resins. is there. In addition, the raw material of the cylindrical member 32 and the collar member 33 is not limited to a synthetic resin. For example, the material of the cylindrical member 32 and the flange member 33 may be a metal.

Further, as shown in FIGS. 2A and 2B and FIG. 4, a packing 36 (waterproof packing) is provided on the surface 33 a that contacts the main pipe 22 of the flange member 33 to improve the water-stopping property due to the contact with the main pipe 22. ) Can be provided.
The spacer 56 and the packing 36 are formed of rubber having elasticity such as a low resilience material or a water expansion / water blocking material. Examples of the material of the spacer 56 and the packing 36 include polyurethane, hard urethane, nitrile rubber, hydrogenated nitrile rubber, various fluororubbers, EPDM, silicone rubber, perfluoroelastomer, Teflon (registered trademark), fluororesin, PEEK, PA , POM, UHMW-PE, etc. are used.

  The packing 36 of the first embodiment has a thickness of about 5 mm. The packing 36 is attached to the surface 33a that contacts the outer periphery of the main pipe 22 of the flange member 33 using an adhesive. Examples of adhesives include rubber adhesives, epoxy adhesives, cyanoacrylic adhesives, vinyl adhesives, silicone rubber adhesives, plastic adhesives, hot bonds / hot melts, and adhesive tapes. Use.

  However, the flange member 33 may not be provided with the spacer 56 or the packing 36. For example, when the collar member 33 is formed of a synthetic resin having a lower hardness than the main tube 22 or the cylindrical member 32 and having a high degree of deformability, and the water stopping property can be secured by the deformation, the engagement of the annular protrusion 88 is achieved. The spacer 56 may not be provided between the stop surface 88a and the flat portion 90 of the flange member 33, and the packing 36 may not be provided on the surface 33a of the flange member 33. However, in consideration of long-term and reliable water stoppage of the branch joint 30, a spacer 56 is provided between the locking surface 88 a of the annular projecting portion 88 and the flat portion 90 of the flange member 33, and the surface of the flange member 33. It is desirable to provide a packing 36 on 33a.

  FIG. 5 is a perspective view of the fixing member 41. The fixing member 41 is a nut-like member having a spherical portion 42 (inclined portion) that contacts an edge 25a (see FIG. 2) of the opening 25 of the main pipe 22 at one end and a rotation imparting portion 43 at the other end. The fixing member 41 has a through-hole 44 that penetrates in the longitudinal direction inside the cylindrical shape. The through hole 44 has a dimension that allows the locking portion 37 of the cylindrical member 32 to be inserted therein. The through hole 44 is provided with an engaging portion 46 (female screw) that engages with the engaging portion 37 of the cylindrical member 32. The engaging portion 46 of the first embodiment is formed in a screw shape protruding inward in the radial direction of the through hole 44.

The spherical portion 42 (inclined portion) has a tip portion 42 a having a smaller diameter than the outer diameter of the guide portion 38, and a root portion 42 b of the spherical portion 42 having a larger diameter than the opening 25. To do. In addition, the outer diameter of the guide part 38 of 1st Embodiment is 34.5 mm in diameter. And the front-end | tip part 42a (front end side) of the spherical part 42 of 1st Embodiment is formed in diameter 33.4mm, and the diameter of the base part 42b (other end side) of the spherical-surface part 42 is formed in 49.5mm. Then, the spherical surface of the spherical surface portion 42 is formed into a spherical surface connecting the tip portion 42a and the root portion 42b of the spherical surface portion 42 with a curve.
In the present embodiment, a spherical spherical portion 42 is provided as the inclined portion. However, the present invention is not limited to the configuration having a spherical shape. If the tip end portion 42a is smaller than the diameter of the opening 25 and the root portion 42b is larger than the diameter of the opening 25, the inclined surface is conically formed. It may be provided.

  The spherical portion 42 of the first embodiment is formed on a spherical surface of R30 mm, which has a steeper curvature than the inner diameter of the main tube 22. The distal end portion 42 a of the spherical surface portion 42 is formed in a shape that does not contact the guide portion 38 of the cylindrical member 32. The specific shape of the tip 42a is such that the tip of the spherical surface of R30 mm is cut off with a smaller diameter than the outer diameter of the guide 38, as shown in the cross sections of FIGS. 2 (A) and 2 (B).

  The rotation imparting portion 43 has a plurality of concave portions 47 and convex portions 48 along the circumferential direction of the fixing member 41. Specifically, six concave portions 47 and six convex portions 48 are formed at equal intervals in the rotation imparting portion 43. By the plurality of concave portions 47 and convex portions 48 of the rotation imparting portion 43, the operator can easily grip the fixing member 41 and perform the tightening operation.

  The shape of the rotation imparting unit 43 is not limited to the shape described above. For example, the rotation imparting portion 43 may be formed in a hexagonal nut shape, and the rotation imparting portion 43 may be tightened using a tool such as a spanner or a wrench. If the rotation imparting portion 43 is tightened using a tool, the operator can tighten the fixing member 41 more firmly, and the branch joint 30 can be securely attached to the main pipe 22. The engaging portion 46 is engaged with the locking portion 37 of the tubular member 32 by tightening by the rotation applying portion 43. The engagement between the engaging portion 46 of the fixing member 41 and the engaging portion 37 of the cylindrical member 32 fixes the branch joint 30 in the opening 25 of the main pipe 22.

The fixing member 41 is made of, for example, a synthetic resin such as vinyl chloride resin. The material of the fixing member 41 is not limited to polyvinyl chloride, and may be, for example, soft polyvinyl chloride. Soft polyvinyl chloride has a lower hardness and higher deformability than polyvinyl chloride. That is, the fixing member 41 formed of soft polyvinyl chloride has a large amount of deformation when the engaging portion 46 is engaged with the engaging portion 37 of the cylindrical member 32. For this reason, the fixing member 41 formed of soft polyvinyl chloride can improve the engaging force of the fixing member 41 and is not easily loosened, and the branch joint 30 can be securely attached to the main pipe 22. However, the material of the fixing member 41 is not limited to synthetic resin. For example , the material of the fixing member 41 may be a metal.

Next, the procedure for attaching the branch joint 30 to the opening 25 of the main pipe 22 will be described with reference to FIGS.
The main tube 22 of the first embodiment has an outer diameter of 165 mm, a tube wall thickness of 5.1 mm, and an inner diameter of approximately 154 mm. The JIS standard dimension of the tube wall thickness is 5.1 (+0.8 to −0), and the inner diameter is a reference value.

  First, as shown in FIG. 6A, an opening 25 is formed in the main pipe 22 using a hole saw 51. The size of the opening 25 to be drilled by the hole saw 51 varies depending on the skill level of the operator who performs the drilling work and the performance of the hole saw 51. When the size of the opening 25 is set to 35 mm, the actual diameter of the opening 25 in FIG. 6B is, for example, about 35 mm to 40 mm.

  Next, as shown in FIG. 6C, the opening 25 of the main pipe 22 is covered with the flange member 33 through the packing 36, and the hole 89 (see FIGS. 2 and 4) of the flange member 33 and the main pipe 22 are formed. The center of the opening 25 is made to substantially coincide. Further, the insertion cylinder portion 32 a of the cylindrical member 32 is inserted into the hole 89 of the flange member 33 and the opening 25 of the main pipe 22. FIG. 6C shows a state in the middle of inserting the cylindrical member 32 into the hole 89 of the flange member 33 and the opening 25 of the main pipe 22. When completely inserted, the annular protrusion 88 of the cylindrical member 32 comes into contact with the flange member 33. In other words, when the cylindrical member 32 is completely inserted, the locking surface 88a of the annular projecting portion 88 and the flat portion 90 of the flange member 33 directly contact each other. When the spacer 56 is inserted between the locking surface 88a and the flat portion 90 (see FIG. 2A), the locking surface 88a of the annular protrusion 88 and the flat portion 90 of the flange member 33 are The spacer 56 is clamped.

  The cylindrical member 32 has a guide portion 38. As shown in FIG. 3, the guide portion 38 has the same diameter portion 39 having a length shorter than the thickness of the tube wall of the main pipe 22 and a tapered portion 40 that is reduced in diameter from the same diameter portion 39 toward the terminal side. First, the tapered portion 40 of the guide portion 38 smoothly guides the cylindrical member 32 into the opening 25. Then, the same-diameter portion 39 of the guide portion 38 smoothly moves the cylindrical member 32 toward the center in the opening 25 by screwing the engaging portion 46 of the fixing member 41 and the engaging portion 37 of the cylindrical member 32. To guide. That is, the guide portion 38 performs a centering function for guiding the cylindrical member 32 within the opening 25.

  In addition, the flange member 33 is formed in a shape that is looser than the outer diameter of the main pipe 22 and substantially follows the outer diameter of the main pipe 22. The flange member 33 substantially positions the cylindrical member 32 on the main pipe 22. The gentle diameter referred to here means that the curvature of the flange member 33 is a curvature that is substantially the same as the curvature of the outer diameter of the main pipe 22 and is gentler than the outer diameter of the main pipe 22. The eaves member 33 of the first embodiment is formed to R108 mm, for example. For this reason, the branch joint 30 can be attached to the main pipe 22 in the range of the loose diameter of the flange member 33 even if the outer diameter of the main pipe 22 is changed from 165 mm to the main pipe 22 having an outer diameter of about 216 mm. Further, since the flange member 33 is formed separately from the cylindrical member 32, the flange member 33 can be replaced with another flange member 33 having a different curvature according to the outer diameter of the main pipe 22. When the flange member 33 covers the opening 25 of the main pipe 22 and comes into contact with the outer diameter of the main pipe 22, the cylindrical member 32 is substantially positioned in the opening 25.

  Next, the operation of engaging the fixing member 41 with the cylindrical member 32 is performed by opening the lid portion 23 (see FIG. 1) that covers the upper portion of the main pipe 22 so that the state shown in FIG. The fixing member 41 fixes the substantially positioned tubular member 32 in the opening 25 of the main pipe 22 from the inside of the main pipe 22. The fixing member 41 is provided with a spherical portion 42 that abuts on the edge 25 a of the opening 25 of the main pipe 22. The spherical surface portion 42 has a tip end portion 42a (see FIGS. 2 and 5) having a smaller diameter than the outer diameter of the guide portion 38 (see FIGS. 2 and 3). Further, the spherical portion 42 has a base portion 42 b (see FIGS. 2 and 5) having a larger diameter than the opening 25.

  The spherical portion 42 of the first embodiment is formed to have a radius of R30 mm that is a steeper curvature than the inner diameter of the main tube 22. When the engaging portion 46 of the fixing member 41 and the engaging portion 37 of the tubular member 32 are engaged with each other, the distal end portion 42 a of the spherical portion 42 is connected to the guide portion 38 of the tubular member 32. The tip of the spherical surface of R30 mm is cut off with a size smaller than the outer diameter of the guide portion 38 so as not to contact. When the engaging portion 46 of the fixing member 41 and the engaging portion 37 of the tubular member 32 are engaged with each other by the spherical portion 42, the fixing member 41 is in contact with the edge 25 a of the opening 25 and the inner diameter of the main tube 22. Can rotate smoothly. Further, since the spherical portion 42 is tapered from the root portion 42 b toward the tip portion 42 a, the spherical portion 42 is inserted into the opening 25 to make the central axis of the fixing member 41 coincide with the central axis of the opening 25. Performs centering function. In addition, the spherical portion 42 is a spherical surface that connects the base portion 42b and the tip portion 42a with a curve, and thus abuts against the edge 25a of the opening 25 along the inner diameter of the main tube 22. As a result, centering with little backlash can be performed on the opening 25.

  The front end portion 42 a of the spherical portion 42 is formed to have a smaller diameter than the outer diameter of the guide portion 38. For this reason, the spherical surface portion 42 of the fixing member 41 can smoothly guide the branch joint 30 from the inside of the main pipe 22 in the opening 25. The guide portion 38 of the tubular member 32 smoothly guides the branch joint 30 from the outside of the main pipe 22 toward the center in the opening 25. Thus, the guide portion 38 of the cylindrical member 32 and the spherical portion 42 of the fixing member 41 guide the branch joint 30 from the inside of the main tube 22 and the outside of the main tube 22 toward the center of the opening 25 of the main tube 22. . For this reason, the branch joint 30 can be accurately attached to the opening 25 having variations in dimensions.

  The guide portion 38 of the cylindrical member 32 and the spherical portion 42 of the fixing member 41 are a tapered portion 40 provided in the guide portion 38 and a spherical portion having a shape in which the tip is cut off with a smaller diameter than the outer diameter of the guide portion 38. 42, there is a gap that does not contact each other even when the branch joint 30 is fixed to the main pipe 22. Specific dimensions of the gap include the engagement portion 46 of the fixing member 41 and the engagement portion 37 of the cylindrical member 32 without providing the packing 36 on the surface 33a (see FIG. 2) that contacts the main pipe 22 of the flange member 33. When the branch joint 30 is fixed to the opening 25 of the main pipe 22 by engaging with each other, the distance between the guide portion 38 of the cylindrical member 32 and the spherical portion 42 of the fixing member 41 is about 0.51 mm.

  A 5 mm packing 36 is provided on a surface 33 a (see FIG. 2) that contacts the main pipe 22 of the flange member 33 in an unloaded state, and the engagement between the locking portion 37 of the cylindrical member 32 and the engaging portion 46 of the fixing member 41. When the packing 36 is crushed to a thickness of about 2 mm, the size of the gap is about 1.42 mm. Further, a 5 mm packing 36 is provided on one surface 33 a of the flange member 33 in an unloaded state, and the packing 36 is crushed by the engagement between the locking portion 37 of the cylindrical member 32 and the engaging portion 46 of the fixing member 41. When the thickness is about 1 mm, the size of the gap is about 0.97 mm.

That is, the guide portion 38 of the cylindrical member 32 and the spherical portion 42 of the fixing member 41 do not contact each other when the branch joint 30 is fixed to the main pipe 22 regardless of the presence or absence of the packing 36. For this reason, even if the fixing member 41 is retightened in accordance with deterioration of the packing 36 due to temperature change or long-term use, the guide portion 38 of the cylindrical member 32 and the spherical surface portion 42 of the fixing member 41 are in contact with each other. do not do.
The spacing between the guide portion 38 of the cylindrical member 32 and the spherical portion 42 of the fixing member 41 is such that the spacer 56 (see FIG. 2) provided between the locking surface 88a of the annular protrusion 88 and the flat portion 90 of the flange member 33. (See (A)).

  Next, as shown in FIG. 6E, the secondary pipe 20 is connected to the outer cylindrical portion 32 b of the branch joint 30 that is fixed to the main pipe 22. In the first embodiment, the auxiliary pipe 20 is inserted and connected from the outer cylinder part 32b side of the cylindrical member 32 until it contacts the step part 35 (see FIG. 2). By connecting the sub pipe 20 and the main pipe 22 via the branch joint 30, the drain 16 of the latent heat recovery type gas water heater 1 can be discharged from the main pipe 22 to the downstream pipe 24.

  In the branch joint 30, a water sealing mechanism may be provided at a portion where the drain pipe 16 is discharged from the sub pipe 20 to the main pipe 22 via the branch joint 30. When providing a water sealing mechanism in the branch joint 30, a dedicated trap can be inserted and connected, and attachment / detachment for maintenance management is possible. Moreover, you may comprise a sealing mechanism by the combination of a general purpose pipe and a coupling, for example.

  In addition, the connection method of piping (for example, sub pipe 20) connected to the branch joint 30 is not limited to the insertion to the branch joint 30. For example, the secondary pipe 20 may be extrapolated and connected to the cylindrical member 32 of the branch joint 30 without forming the step portion 35 in the through hole 34 of the cylindrical member 32. Further, the connection of the secondary pipe 20 to the cylindrical member 32 may be firmly connected using an adhesive, or the secondary pipe 20 and the cylindrical member 32 may be screwed together by providing a screw portion. Alternatively, a connection by pressure contact between the secondary pipe 20 and the cylindrical member 32 may be used. Further, for example, the through hole 34 of the tubular member 32 of the first embodiment is formed with a groove that is recessed outward in the radial direction of the through hole 34, and packing is provided in the groove to stop the branch joint 30 and the pipe. The aqueous property may be improved.

Next, it will be described with reference to FIGS. 7 to 12 that the branch joint 30 can be attached with high accuracy even when the dimensions of the opening 25 vary. In the following embodiments, the outer diameter of the same diameter portion 39 of the guide portion 38 of the cylindrical member 32 is 34.5 mm.
First, a case where the branch joint 30 is attached to the main pipe 22A having an outer diameter of 165 mm, a pipe wall thickness of 5.1 mm, and an inner diameter of approximately 154 mm based on FIGS. 7 to 9 will be described. (First to third application examples).

<First application example>
First, a first application example will be described with reference to FIG. An opening 25A having a diameter of 35 mm is formed in the main tube 22A of this application example shown in FIG. The insertion tube portion 32a of the tubular member 32 is inserted into the opening 25A. The cylindrical member 32 can be smoothly inserted into the opening 25 </ b> A by the action of the tapered portion 40 of the guide portion 38. And the same diameter part 39 of the guide part 38 formed in 34.5 mm which is substantially the same diameter as 35 mm of diameter 25A of the opening 25A of the main pipe 22A is a peripheral surface and part of opening 25A with the insertion of the cylindrical member 32. Abut. The same diameter portion 39 of the guide portion 38 functions as a centering function for guiding the cylindrical member 32 toward the center of the opening 25A. The tubular member 32 is substantially positioned in the opening 25 </ b> A when the flange member 33 covers the opening 25 </ b> A of the main pipe 22 </ b> A and contacts the outer diameter of the main pipe 22 </ b> A.

The fixing member 41 is attached to the cylindrical member 32 in the substantially positioned state from the inside of the main pipe 22A. When the branch joint 30 is fixed to the opening 25A of the main pipe 22A by the fixing member 41, the spherical portion 42 of the fixing member 41 contacts the inner diameter of the main pipe 22A. Since the inner diameter (inner peripheral surface) of the main tube 22A is cylindrical, when the spherical portion 42 is pressed against the opening 25A from the inside of the main tube 22A, the spherical portion 42 partially contacts the edge 25a of the opening 25A.
In FIG. 7B, a portion (abutting portion 26A) that abuts against the projection line of the opening 25A is highlighted with a bold line. As shown in FIG. 7B, it abuts on both sides of the opening 25A with a predetermined length with respect to the axial direction of the main pipe 22A (forms the abutment portion 26A).
The length (the length of the abutting portion 26A in FIG. 7B) of the portion where the spherical portion 42 abuts against the aperture 25A is projected in the axial direction of the aperture 25A is called the abutting portion projected length. I will do it. The circumference of the opening 25A (the circumference when the opening 25A is projected in the axial direction) is referred to as the total circumference. At this time, the ratio of the contact projection length to the entire circumference of the opening 25A is defined as follows.
Contact portion ratio (%) = 100 × contact portion projected length (mm) / total circumference (mm)

  In the first application example shown in FIG. 7, the total circumference is about 109.96 mm, and the abutment projection length is about 38.47 mm. Accordingly, the ratio of the contact portion with the spherical portion 42 at the edge 25a of the opening 25A is about 35%. This contact portion ratio indicates that the spherical portion 42 is in contact with the edge 25a of the opening 25A by about 35% (about 1/3). Further, it means that about 1/3 of the spherical portion 42 performs the centering function with respect to the edge 25a. In other words, when the diameter of the opening 25A is 35 mm, about 2/3 of the entire circumference of the portion corresponding to the diameter 35 mm of the spherical portion 42 does not perform the centering function.

  However, in the first application example, the guide member 38 has the same diameter by insertion of the cylindrical member 32 into the opening 25 </ b> A or screwing of the engaging portion 46 of the fixing member 41 and the locking portion 37 of the cylindrical member 32. The portion 39 is in contact with the opening 25A to perform the centering function. That is, in this application example, the centering function by the same diameter part 39 of the guide part 38 and the centering function by the spherical surface part 42 of the fixing member 41 act as the centering function to guide the branch joint 30 to the opening 25A. To do. For this reason, the branch joint 30 can be attached to the opening 25 </ b> A of the main pipe 22 </ b> A with high accuracy by the engagement between the locking portion 37 of the cylindrical member 32 and the engaging portion 46 of the fixing member 41.

<Second application example>
Next, a second application example will be described with reference to FIG. An opening 25B having a diameter of 38 mm is formed in the main pipe 22A of this application example. When the branch joint 30 is fixed to the opening 25B of the main pipe 22A, the spherical portion 42 of the fixing member 41 contacts the edge 25a of the opening 25B. When the diameter of the opening 25B is 38 mm, the length (contact portion projection length) of the portion (contact portion 26B) where the spherical portion 42 and the opening 25B are in contact is about 76.42 mm. Is about 119.38 mm. Therefore, the contact portion ratio between the spherical portion 42 and the opening 25B is about 64%.

  This contact portion ratio means that about 2/3 of the total circumference of the portion corresponding to the diameter of 38 mm of the spherical portion 42 fulfills the centering function. In other words, in the second application example, about 1/3 of the entire circumference of the spherical portion 42 corresponding to the diameter of 38 mm does not perform the centering function.

  However, in the second application example, the guide member 38 has the same diameter by inserting the cylindrical member 32 into the opening 25 </ b> B or screwing the engaging portion 46 of the fixing member 41 and the locking portion 37 of the cylindrical member 32. The portion 39 performs an auxiliary centering function while contacting the opening 25B. That is, when the diameter of the opening 25B is 38 mm, the auxiliary centering function by the same diameter part 39 of the guide part 38 and the centering function by the spherical part 42 of the fixing member 41 complement each other, and the branch joint 30 Can be guided to the opening 25B and centered.

<Third application example>
Next, a third application example will be described with reference to FIG. An opening 25C having a diameter of 40 mm is formed in the main pipe 22A of this application example. When the branch joint 30 is fixed to the opening 25C of the main pipe 22A, the spherical portion 42 of the fixing member 41 contacts the edge 25a of the opening 25C.
In the third application example, the length (contact portion projection length) of the portion (contact portion 26C) where the spherical portion 42 and the edge 25a of the opening 25C contact is approximately 111.43 mm. The total circumference is about 125.66 mm. Therefore, the contact portion ratio between the spherical portion 42 and the opening 25C is about 89%.

  This contact portion ratio means that about 89% of the entire circumference of the spherical portion 42 corresponding to the diameter of 40 mm fulfills the centering function. The same-diameter portion 39 and the opening 25C of the guide portion 38 screw the engaging portion 46 of the fixing member 41 and the engaging portion 37 of the cylindrical member 32 even when the cylindrical member 32 is inserted into the opening 25C. However, there is almost no contact. Therefore, the guide portion 38 hardly performs an auxiliary centering function. However, in the third application example, most of the length of the portion corresponding to the circumference of the spherical surface portion 42 of the fixing member 41 performs the centering function for guiding the branch joint 30 to the opening 25C. That is, in the third application example, the spherical portion 42 performs a sufficient centering function.

  In the first to third application examples described above, the outer diameter of the main pipe 22A is 165 mm. Further, the flange member 33 of the cylindrical member 32 is formed with a radius of R108 mm in a direction along the outer diameter of the main pipe 22A with a smaller diameter than the outer diameter of the main pipe 22A. For this reason, even when the dimensions of the main pipe 22A are changed to a main pipe 22A of another size having an outer diameter of 165 mm, an approximate inner diameter of 154 mm, and a pipe wall thickness of not 5.1 mm, It is possible to ensure the water-stopping and fixing properties of the branch joint 30 by being in close contact with the outer diameter of the main pipe 22A within the range of the gradual diameter of the flange member 33.

  In the fourth to sixth application examples described below based on FIGS. 10 to 12, the branch joint 30 has an outer diameter of 216 mm, a tube wall thickness of 6.5 mm, and an inner diameter of an approximate inner diameter of 202 mm. The case where the branch joint 30 is attached to the main pipe 22B will be described (fourth to sixth application examples).

<Fourth application example>
A fourth application example will be described with reference to FIG. An opening 25D having a diameter of 35 mm is formed in the main tube 22B of this application example. When the branch joint 30 is fixed to the opening 25D of the main pipe 22B, the spherical portion 42 of the fixing member 41 abuts on the edge 25a of the opening 25D. When the diameter of the opening 25D is 35 mm, the length (contact portion projection length) of the portion (contact portion 26D) where the spherical portion 42 and the opening 25D are in contact is about 45.18 mm. Is about 109.96 mm. Therefore, the contact portion ratio between the spherical portion 42 and the opening 25D is about 41%.
In the fourth application example, the same-diameter portion 39 of the guide portion 38 abuts the opening 25D to perform the centering function, whereby the branch joint 30 can be accurately attached to the opening 25D of the main pipe 22B.

<Fifth application example>
A fifth application example will be described with reference to FIG. An opening 25E having a diameter of 38 mm is formed in the main tube 22B of this application example. When the branch joint 30 is fixed to the opening 25E of the main pipe 22B, the spherical portion 42 of the fixing member 41 contacts the edge 25a of the opening 25E. When the diameter of the opening 25E is 38 mm, the length (contact portion projected length) of the portion (contact portion 26E) where the spherical portion 42 and the opening 25E are in contact is about 101.47 mm. Is about 119.38 mm. Therefore, the contact portion ratio between the spherical portion 42 and the opening 25E is about 85%. Therefore, in the fifth application example, the auxiliary centering function by the same diameter portion 39 of the guide portion 38 and the centering function by the spherical surface portion 42 of the fixing member 41 complement each other to guide the branch joint 30 to the opening 25E. It can be centered and attached with high accuracy.

<Sixth application example>
A sixth application example will be described with reference to FIG. An opening 25F having a diameter of 40 mm is formed in the main tube 22B of this application example. When the branch joint 30 is fixed to the opening 25F of the main pipe 22B, the spherical portion 42 of the fixing member 41 contacts the edge 25a of the opening 25F. When the diameter of the aperture 25F is 38 mm, the length (abutment projection length) of the portion (abutment portion 26F) where the spherical portion 42 and the aperture 25F are in contact is about 125.66 mm. Is about 125.66 mm. Therefore, the contact portion ratio between the spherical portion 42 and the opening 25F is about 100%. Accordingly, only a contact portion 26F between the spherical surface portion 42 and the opening 25F performs a sufficient centering function and can be attached with high accuracy.

  In the fourth to sixth application examples described above, the outer diameter of the main tube 22B is 216 mm (radius 108 mm). Further, the flange member 33 has a curvature of R108 mm in a direction along the outer diameter of the main tube 22B with the same radius of curvature as the outer diameter of the main tube 22B. Therefore, like the first to third application examples described above, the flange member 33 can be in close contact with the outer diameter of the main pipe 22B to ensure the water-stopping property and the fixing property of the branch joint 30.

According to the branch joint 30 of the first embodiment, as shown in the first to sixth application examples, even if the dimensions of the opening 25 (openings 25A, 25B, 25C, 25D, 25E, 25F) vary, The branch joint 30 can be attached to the main pipe 22 (main pipes 22A and 22B) with high accuracy, and water stopping and fixing properties can be secured. That is, according to the branch joint 30 of the first embodiment, an operator who drills the opening 25 does not need to be skilled in drilling work. Further, according to the branch joint 30 of the first embodiment, the guide portion 38 of the cylindrical member 32 and the spherical portion 42 of the fixing member 41 center the branch joint 30 with respect to the opening 25, and thus the main pipe 22. The branch joint 30 can be attached with high accuracy.
In the present embodiment, the fixed member 41 is formed with a spherical portion 42 that is a spherical surface. However, the branch joint 30 can be centered with respect to the opening 25 as long as it has an inclination (for example, a linear taper) even if it is not a spherical surface. That is, the present invention is not limited to the inclination of the spherical surface, and may be provided with a curved surface other than the spherical surface (for example, a linear taper) instead of the spherical surface portion 42. In addition, by providing the spherical surface portion 42 that is a spherical surface, it is possible to obtain a more special effect of centering while complementing each other with the guide portion 38.

  Further, according to the branch joint 30 of the first embodiment, the operator can connect the branch joint 30 to the opening 25 by the engagement of the locking portion 37 of the cylindrical member 32 and the engagement portion 46 of the fixing member 41. Can be installed. That is, the operator can shorten the time for attaching the branch joint 30 to the main pipe 22.

  Further, according to the branch joint 30 of the first embodiment, the operator simply inserts the insertion tube portion 32a of the tubular member 32 into the opening 25 and tightens the fixing member 41 from the inside of the main tube 22. The branch joint 30 can be guided with respect to the opening 25. For this reason, even if there is variation in the dimensions of the opening 25, the operator does not need to adjust the position when installing the branch joint 30. For this reason, the branch joint 30 of the first embodiment has good mounting workability.

  Further, in the case of the prior art in which the branch joint 30 is fixed from the outside of the main pipe 22, it is necessary to make the cylindrical member 32 and the flange member 33 separate from each other, which increases the number of parts. Expenses and part management costs increase. However, according to the branch joint 30 of the first embodiment, the flange member 33 of the branch joint 30 has a gentle diameter that is gentler than the curvature of the outer diameter of the main pipe 22 and is substantially in the circumferential direction of the outer diameter of the main pipe 22. Form along the shape. For this reason, the branch joint 30 of the first embodiment can be closely attached to the outer diameter of the main pipe 22 in the range of the loose diameter of the flange member 33 and can be attached with high accuracy, and the water tightness of the branch joint 30 can be ensured. Further, the flange member 33 of the branch joint 30 of the first embodiment can be replaced with another flange member 33 formed with a different curvature according to the size of the outer diameter of the main pipe 22. That is, according to the branch joint 30 of the first embodiment, since the parts can be shared, the number of parts, manufacturing costs, and parts management costs can be reduced.

  Further, according to the branch joint 30 of the first embodiment, the branch between the guide portion 38 of the cylindrical member 32 and the spherical portion 42 of the fixing member 41 branches to the main pipe 22 regardless of the presence or absence of the packing 36 and the spacer 56. Even if the joint 30 is fixed, they do not contact each other. For this reason, the fixing member 41 can be tightened in accordance with the deterioration of the packing 36 due to temperature change, long-term use, etc., and water-stopping can be ensured. That is, the branch joint 30 according to the first embodiment does not require the branch joint 30 to be disassembled or the packing 36 or the spacer 56 to be replaced when the water stoppage decreases due to long-term use. In other words, the branch joint 30 according to the first embodiment does not require labor for maintenance.

  Further, in the branch joint 30 of the first embodiment, the flange member 33 is formed in a shape that is looser than the outer diameter of the main pipe 22 and substantially follows the outer diameter of the main pipe 22. Therefore, even when the size of the main pipe 22 to which the branch joint 30 is attached is changed, the branch joint 30 can secure the water-stopping property and the fixing property of the branch joint 30 because the flange member 33 is in close contact with the outer diameter of the main pipe 22. . For this reason, the branch joint 30 of 1st Embodiment can make components common with respect to the main pipe 22 of a different size, and can reduce manufacturing cost and management cost of components.

  In the branch joint 30 of the first embodiment, the tubular member 32 and the flange member 33 are formed of different members, and the flange member 33 is formed with a curvature radius R of 108 mm, for example. As the first to third application examples, the branch joint 30 is illustrated as being attached to the main pipe 22A having an outer diameter of 165 mm (radius: 82.5 mm). Moreover, the example attached to the main pipe 22B of outer diameter 216mm (radius 108mm) was shown as a 4th-6th application example. In this way, by setting the radius of curvature of the flange member 33 to be the same radius or a gentle diameter as the outer diameter of the main pipe 22A, it is possible to ensure both waterproofness and fixability at the same time.

The flange member 33 is formed of a member separate from the cylindrical member 32. Therefore, the flange member 33 can be replaced with one having a different curvature radius according to the outer diameter of the main pipe 22.
FIGS. 13A to 13C show a state in which three types of flange members 33A, 33B, and 33C having three curvature radii r1 to r3 are arranged so as to cover the periphery of the opening 25 of the main pipe 22, respectively. .

The curvature radius r1 of the flange member 33A shown in FIG. 13A matches the curvature radius of the outer diameter of the main pipe 22 (a state equivalent to Application Examples 4 to 6). For example, this is a case where the radius of curvature r1 of the flange member 33A is R108 mm with respect to the main pipe 22 having an outer diameter of 216 mm (radius 108 mm).
Thus, when selecting the flange member 33A having a curvature radius that matches the outer diameter of the main pipe 22, it is possible to ensure water-stopping and fixing properties.

On the other hand, the radius of curvature r2 of the flange member 33B shown in FIG. 13B is smaller than the radius of curvature of the outer diameter of the main pipe 22. For example, the curvature radius r2 of the flange member 33B is R90 mm with respect to the main pipe 22 having an outer diameter of 216 mm (radius 108 mm).
In such a case, the flange member 33 </ b> B is deformed so as to follow the outer diameter of the main pipe 22 by the pinching force between the tubular member 32 and the fixing member 41. Therefore, the surface pressure between the flange member 33 </ b> B and the outer periphery of the main pipe 22 is increased, and the water stoppage can be further increased. However, if there is a difference in the radius of curvature that exceeds the range in which the flange member 33B can be deformed, there is a risk of causing water leakage. Therefore, when it has a curvature radius smaller than the outer diameter of the main pipe 22 like the flange member 33B, the applicable range becomes narrow.
Specifically, the radius of curvature r2 of the flange member 33B is preferably 65% or more with respect to the radius of the outer diameter of the main pipe 22. For example, a 5 mm packing 36 is provided on a surface 33 a (see FIG. 2) that contacts the main pipe 22 of the flange member 33 in an unloaded state, and the locking portion 37 of the cylindrical member 32 and the engaging portion 46 of the fixing member 41 are provided. If the packing 36 is crushed by 3 mm to a thickness of about 2 mm and the entire surface of the packing 36 is in contact with the main tube 22, the radius of curvature of the flange member 33 is 216 mm (radius 108 mm). It is preferable that the radius of curvature r2 of the flange member 33B is 70 mm or more with respect to the main pipe 22.

Moreover, the curvature radius r3 of the flange member 33C shown in FIG. For example, the curvature radius r3 of the flange member 33 is R120 mm with respect to the main pipe 22 having an outer diameter of 216 mm (radius 108 mm).
Thus, by selecting the flange member 33 </ b> C having a radius of curvature that is gentler than the outer diameter of the main pipe 22, it is possible to ensure water stopping and fixing properties. However, if the radius of curvature r3 of the flange member 33 is too large with respect to the radius of curvature of the outer diameter of the main tube 22, the flange member 33C cannot follow the outer periphery of the main tube 22, and a gap is generated to ensure water stopping. There is a possibility that it cannot be done.
Specifically, the radius of curvature r3 of the flange member 33C is preferably 150% or less with respect to the radius of the outer diameter of the main pipe 22. For example, a 5 mm packing 36 is provided on a surface 33 a (see FIG. 2) that contacts the main pipe 22 of the flange member 33 in an unloaded state, and the locking portion 37 of the cylindrical member 32 and the engaging portion 46 of the fixing member 41 are provided. If the packing 36 is crushed by 3 mm to a thickness of about 2 mm and the entire surface of the packing 36 is in contact with the main tube 22, the radius of curvature of the flange member 33 is 216 mm (radius 108 mm). It is preferable that the curvature radius r3 of the flange member 33B is 160 mm or less with respect to the main pipe 22.

When the curvature radius of the flange member 33 (the flange members 33A to 33C) does not match the outer diameter of the main pipe 22, that is, the curvature radius of the flange member 33 is less than 65% with respect to the radius of the outer diameter of the main pipe 22. Or when it exceeds% 150%, there is a possibility that sufficient water stoppage cannot be secured.
The branch joint 30 of the present embodiment can select the flange member 33 according to the outer diameter of the main pipe 22 by forming the flange member 33 separately from the cylindrical member 32. Therefore, when a plurality of sizes of the eaves member 33 are prepared and the eaves member 33 is properly used according to the size of the main pipe 22, the branch joint 30 can ensure the watertightness according to the pressure of the fluid and the use, and A wide range of changes in the dimensions of the main pipe 22 can be accommodated simply by replacement.
Further, in the branch joint 30 of the first embodiment, a plurality of types of shapes of the flange member 33 are prepared with a gentle diameter that is gentler than the curvature of the outer diameter of the main pipe 22, or substantially the same as the curvature of the outer diameter of the main pipe 22. There are several kinds of curvatures. Thereby, the branch joint 30 can adapt to the dimension of the wider main pipe 22 only by changing the flange member 33.

  Moreover, the branch joint 30 of 1st Embodiment forms the cylindrical member 32 and the collar member 33 by another member. The annular protrusion 88 of the cylindrical member 32 forms a locking surface 88a on one side of the cylindrical member 32 in a plane, and the hole 89 of the flange member 33 contacts the locking surface 88a of the annular protrusion 88. The flat portion 90 is formed so as to protrude from the other side of the flange member 33, and the spacer 56 is disposed between the locking surface 88 a of the annular protrusion 88 and the flat portion 90 of the flange member 33. For this reason, even if the thickness of the pipe wall of the main pipe 22 (a JIS standard dimension of 5.1 mm is a width of +0.8 mm to −0 mm in 5.1), the thickness of the spacer 56 is adjusted to be cylindrical. The guide portion 38 of the member 32 protrudes from the main tube 22 and can prevent contact with the spherical portion 42 of the fixing member 41.

  Further, the hole 89 of the flange member 33 of the first embodiment is formed by protruding a flat portion 90 that contacts the locking surface 88a of the annular protrusion 88 from the other of the flange member 33, and the flat portion 90 and the annular protrusion portion. 88 is in surface contact with the other. For example, a protrusion may be formed on one of the facing surfaces of either the flat portion 90 or the locking surface 88a, and a hole that can be fitted to the protrusion may be formed on the other of the facing surfaces. When the protrusion and the hole are fitted to each other, the cylindrical member 32 and the flange member 33 can be handled as an integral member, so that the insertion operation into the opening 25 and the fixing operation by the fixing member 41 are facilitated. Further, by forming protrusions and holes that can be fitted to each other on the flat portion 90 and the locking surface 88a in this way, when the fixing member 41 is screwed into the tubular member 32, the flange member 33 is connected to the main tube 22. It is possible to suppress the circulation of the cylindrical member 32 along the line.

  Further, in order to handle the cylindrical member 32 and the flange member 33 as an integral member, the same diameter portion 39 of the guide portion 38 and the hole 89 of the flange member 33 formed on the outer periphery of the cylindrical member 32 have substantially the same diameter. It is good also as fitting possible. Further, both the tubular member 32 and the flange member 33 may be provided with threaded portions and engaged and integrated. As described above, when the tubular member 32 and the flange member 33 are fitted or engaged with each other by the threaded portion, the operator can handle the tubular member 32 and the flange member 33 as an integral member. The operation of inserting into the opening 25 and the fixing operation by the fixing member 41 are facilitated. When the cylindrical member 32 and the flange member 33 are integrated by providing a threaded portion, the relationship between the direction of the cylindrical member 32 and the direction of the flange member 33 depends on the presence or absence of the spacer 56 and the thickness of the spacer 56. change. For this reason, a sticking seal or the like may be attached to the cylindrical member 32 so that the direction after assembly can be visually determined.

<< Second Embodiment >>
Next, the branch joint 60 of 2nd Embodiment is demonstrated using FIG. 14 (A), (B). In the second embodiment, the tubular member 32 in the first embodiment is changed to the tubular member 62, and the fixing member 41 is changed to the fixing member 71. Moreover, the eaves member 63 has the same configuration as the eaves member 33 of the first embodiment, and is formed of a separate member from the tubular member 62. The other configurations similar to those of the first embodiment are denoted by the same reference numerals and description thereof is omitted.
The branch joint 60 of the second embodiment differs from the branch joint 30 (see FIG. 2) of the first embodiment in the engagement relationship for fixing the cylindrical member 62 and the fixing member 71. That is, the branch joint 60 of the second embodiment forms a female thread as the locking part 67 of the cylindrical member 62 and a male thread as the engaging part 76 of the fixing member 71, and these threads engage with the main pipe 22. Fix it.

  The branch joint 60 includes a cylindrical member 62, a flange member 63, and a fixing member 71. The cylindrical member 62 has a cylindrical shape having a through-hole 64 inside the cylindrical shape. The cylindrical member 62 is formed with a locking portion 67 (female thread) that engages with a fixing member 71 for fixing the branch joint 60 to the main pipe 22. The locking portion 67 is formed inside the through hole 64 of the cylindrical member 62. A guide portion having an equal diameter portion 69 and a taper portion 70 is formed on the insertion tube portion 62a that protrudes from the annular protrusion portion 98 and is inserted into the opening 25 of the main pipe 22 (on one side of the tubular member 62). 68 is formed. In the second embodiment, the annular projecting portion 98 is formed by projecting a part of the outer cylindrical portion 62b to the outside in the radial direction of the cylindrical member 62 with a larger diameter than one of the cylindrical members 62 (inserted cylindrical portion 62a). doing.

  The fixing member 71 has a spherical portion 72 (inclined portion) that abuts the edge 25a of the opening 25 at one end and a rotation imparting portion 73 at the other end. The fixing member 71 is a bolt-shaped member that extends from one end of the spherical surface portion 72 with a cylindrical portion 75 having a diameter that can be inserted into the through-hole 64 of the cylindrical member 62. The fixing member 71 forms a through-hole 74 that penetrates from the rotation imparting portion 73 to the cylindrical portion 75. The cylindrical portion 75 is provided with an engaging portion 76 (male screw) that can be engaged with a locking portion 67 (female screw) of the cylindrical member 62. The engaging portion 76 is formed in a screw shape projecting radially outward in the outer diameter of the cylindrical portion 75. The through hole 74 of the fixing member 71 is provided with a stepped portion 79 that forms a step by narrowing the inner diameter of the through hole 74. The stepped portion 79 is formed, for example, at the intermediate portion in the longitudinal direction of the fixing member 71.

  Further, a groove 81 that is recessed radially inward of the cylindrical portion 75 is formed on the outer diameter of the cylindrical portion 75. The groove portion 81 is formed, for example, in the vicinity of one end side of the spherical surface portion 72 of the cylindrical portion 75 where the engaging portion 76 is not formed. The groove portion 81 includes a packing 82. The packing 82 increases the water stoppage of the branch joint 60. The packing 82 prevents odor leakage in the drain pipe and infiltration of unknown water from the outside of the main pipe 22. The groove portion 81 of the second embodiment forms a groove portion 81 that is recessed radially inward of the cylindrical portion 75 on the outer diameter of the cylindrical portion 75. However, the groove portion 81 is not limited to the formation of the fixing member 71 on the cylindrical portion. For example, the packing 82 may be provided by forming a groove recessed outward in the radial direction in the through-hole 64 of the cylindrical member 62.

  Then, the operator engages the engaging portion 76 of the fixing member 71 and the engaging portion 67 of the tubular member 62 from the inside of the main tube 22, so that the engaging surface 98 a of the annular projecting portion 98 and the main tube 22 are engaged. A saddle member 63 is arranged between the opening 25 and the branch joint 60 is attached to the opening 25 of the main pipe 22. According to the branch joint 60 of the second embodiment, the guide portion 68 of the cylindrical member 62 and the spherical surface portion 72 of the fixing member 71 guide the branch joint 60 with respect to the opening 25, so that the first embodiment and Similarly, the branch joint 60 can be attached to the main pipe 22 with high accuracy, and water stoppage and fixing properties can be secured. Further, since the flange member 63 is formed separately from the cylindrical member 62, the flange member 63 is replaced with another flange member having a different curvature (for example, the flange member 33A shown in FIG. 13) according to the outer diameter of the main pipe 22. 33B, 33C).

  As shown in FIG. 14 (B), the hole 89 of the flange member 63 of the second embodiment is substantially the same diameter or slightly the same diameter portion 69 of the guide portion 68 formed in the insertion tube portion 62a of the tubular member 62. Form small. Thereby, the cylindrical member 62 and the collar member 63 can be fitted. In this way, by allowing the tubular member 62 and the flange member 63 to be fitted, the operator can combine the tubular member 62 and the flange member 63 and handle them as an integral member. 25 and the fixing work by the fixing member 71 are facilitated.

  In the second embodiment, a concave groove 81 is formed in either the through-hole 64 of the cylindrical member 62 or the outer diameter of the cylindrical portion 75 of the fixing member 71, and a packing 82 (a waterproofing member) is formed in the groove 81. A water stop member is provided. For this reason, the water stop of the branch joint 60 can further be improved. Further, the packing 82 can prevent odor leakage in the drain pipe and infiltration of unknown water from the outside of the main pipe 22.

  As described above, in the present embodiment, the example in which the main pipe 22 is the sewage mass 22 and the sub pipe 20 is the drainage branch 20 and the drain 16 is discharged from the sub pipe 20 to the main pipe 22 has been described. For example, the branch joint may be configured as a pipe that discharges the drain 16 from the main pipe 22 to the sub pipe 20. Moreover, you may use a branch joint for the connection of the sewage mass 22 and the downstream pipe 24 of FIG. Moreover, although the branch joint of this embodiment was used for discharge | emission of the drain 16, another may be sufficient. For example, the branch joint can be applied to connection of other fluid flow paths such as clean water and sewage. The branch joint can also be applied to connection of a gas flow path such as an inflow duct or an exhaust duct.

Next, the invention included in this embodiment will be described.
The branch joint is connectable to the secondary pipe, and includes a cylindrical member inserted into the opening of the main pipe from the outside and a hole through which the cylindrical member is inserted, and is formed on the outer periphery of the cylindrical member A flange member that is disposed between a surface and the main pipe and covers the periphery of the opening from the outside; and an inclined portion that contacts the edge of the opening from the inside of the main pipe, and the cylindrical member includes A fixing member that is screwed from the inside and sandwiches the main pipe via the flange member between the inclined portion and the locking surface.
For this reason, the spherical surface portion (inclined portion) of the fixing member can smoothly rotate with the inner diameter of the main tube while abutting against the edge of the opening when screwed with the locking portion of the cylindrical member. Further, the spherical surface portion is tapered from the root portion toward the tip portion, and when inserted into the opening, there is little backlash, and the fixing member can be smoothly centered in the direction of the center axis of the opening.

The tubular member is provided with a guide portion that guides the branch joint within the opening. The fixing member is provided with a spherical surface portion that abuts against the edge of the opening. The tip end side of the spherical portion is formed with a smaller diameter than the outer diameter of the guide portion, and the other end side of the spherical portion is formed with a larger diameter than the opening.
For this reason, the branch joint can be accurately attached to the opening of the main pipe by the guide portion and the spherical portion of the fixing member. Further, the flange member that comes into contact with the outer diameter of the main pipe can be in close contact with the outer diameter of the main pipe to ensure the water-stopping and fixing properties of the branch joint.

Further, the guide portion has the same diameter portion having a length shorter than the thickness of the main pipe, and a tapered portion that reduces the diameter from the same diameter portion to the terminal. For this reason, when inserting a cylindrical member into an opening, a cylindrical member can be guided to an opening.
Further, the guide portion and the distal end side of the spherical portion have a gap that does not contact each other in a state where the branch joint is fixed to the main pipe. For this reason, a branch joint can be retightened as needed.
Further, packing can be provided between the flange member and the main pipe and between the flange member and the locking surface. The packing can improve the water stoppage of the branch joint and can adjust the thickness error of the pipe wall of the main pipe to ensure a gap between the guide part and the tip side of the spherical part. Further, the packing can prevent odor leakage in the drain pipe and infiltration of unknown water.

Further, the flange member is formed in a shape that is looser than the outer diameter of the main pipe and substantially follows the outer diameter of the main pipe. For this reason, even if the size of the main pipe to which the branch joint is attached is changed, it is possible to secure the water-stopping and fixing property of the branch joint by closely contacting the outer diameter of the main pipe having the same branch joint and different size.
Further, the flange member is formed of a member separate from the cylindrical member. For this reason, the flange member can be exchanged according to the outer diameter of the main pipe. In other words, the branch joint only provides a plurality of molds for the flange member, and there is no need to prepare a plurality of molds for the cylindrical member and the fixing member. That is, the branch joint can expand the application range to the main pipe only by replacing the flange member.
Moreover, the eaves member can replace the eaves member with another eaves member having a different curvature. For this reason, the branch joint can select a flange member that is more suitable for the dimensions of the main pipe, so that more reliable watertightness can be secured.

For example, when the cylindrical member and the flange member having a shape substantially along the main pipe are an integral branch joint, the branch joint is in close contact with the outer diameter of the main pipe within the range of the gradual diameter of the flange member, and the water stoppage of the branch joint. And securing properties. And the adaptation range of a branch joint will be in the range of the gentle diameter of a collar member.
However, in the branch joint according to the embodiment of the present invention, the cylindrical member and the flange member are formed of different members. For this reason, if a gutter member is formed with a steeper curvature, a gutter member will adhere more strongly to a main pipe, and can secure watertightness. In other words, if a plurality of types of collar members are prepared and the collar members corresponding to the size of the main pipe are used properly, the branch joint can ensure water tightness according to the pressure of the fluid and the intended use. And a branch joint can respond to the change of the dimension of a main pipe widely only by replacing | exchanging a collar member.

Moreover, the said locking surface is formed flat, and the said collar member is provided with the flat part which contacts the said locking surface or opposes the said locking surface via packing. For this reason, when fixing a branch joint to a main pipe by screwing of a cylindrical member and a fixing member, a sense of unity with a collar member and an annular projection increases, and it can attach with accuracy and can improve watertightness.
Further, a male screw may be formed on the outer periphery of the cylindrical member, and a female screw that can be screwed to the male screw may be formed on the fixing member. Further, a female screw may be formed on an inner diameter of the cylindrical member, and a male screw that can be screwed to the female screw may be formed on the outer periphery of the fixing member. In any configuration, the effects of the present invention can be achieved, and the branch joint can be accurately attached to the opening of the main pipe.
In the case where a female screw is formed on the inner diameter of the cylindrical member, and the fixing member is cylindrical and a male screw that can be screwed to the female screw is formed on the outer periphery thereof, the screw between the locking portion and the engaging portion is formed. Can be visually confirmed from the outer peripheral side of the main pipe.
Moreover, the guide part of a cylindrical member can be provided in the front end side (insertion side) with respect to a locking surface. For this reason, when inserting a cylindrical member in an opening, while guiding a cylindrical member smoothly, a cylindrical member can be guided with respect to an opening.

Further, in the case where a female screw is formed on the inner diameter of the cylindrical member and the fixing member is cylindrical and a male screw that can be screwed to the female screw is formed on the outer periphery thereof, the inner peripheral surface of the through hole of the cylindrical member It is preferable that a concave groove is formed on any one of the outer peripheral surfaces of the cylindrical portion of the fixing member, and a water stop member (packing) is provided in the groove. For this reason, the water stop member improves water stop and can prevent odor leakage in the drain pipe and infiltration of unknown water.
Moreover, a cylindrical member and a collar member may couple | bond together. Thereby, a cylindrical member and the collar member of another member can be handled as an integral part, and the operation | work at the time of inserting a cylindrical member in the opening of a main pipe becomes easier.

  The present invention can be applied to a branch joint that connects a main pipe and a sub pipe.

1: Latent heat recovery type gas water heater, 2: Hot water heater body, 16: Drain, 18: Drain discharge pipe, 20: Sub pipe (drainage branch), 22, 22A, 22B: Main pipe (sewage mass), 25, 25A , 25B, 25C, 25D, 25E, 25F: opening, 25a: edge, 26A, 26B, 26C, 26D, 26E, 26F: contact part, 30, 60: branch joint, 32, 62: cylindrical member, 32a 62a: insertion cylinder part, 32b, 62b: outer cylinder part, 33, 33A, 33B, 33C, 63: flange member, 34, 44, 64, 74: through hole, 35, 79: step part, 36: packing, 37: Locking part (male thread), 38, 68: Guide part, 39, 69: Same diameter part, 40, 70: Tapered part, 41, 71: Fixing member, 42, 72: Spherical part (inclined part), 42a : Tip part (tip side), 42b: root part (other end side) 43, 73: Rotation imparting part, 46: Engagement part (female thread), 51: Hole saw, 56: Spacer (packing), 67: Locking part (female thread), 75: Cylindrical part, 76: Engagement part (male thread) , 81: groove portion, 82: water stop member (packing), 88, 98: annular projecting portion, 88a, 98a: locking surface, 89: hole, 90: flat portion

Claims (11)

A branch joint that is attached to an opening drilled in a main pipe and connects a sub pipe to form a branch path,
A cylindrical member that is connectable to the sub pipe and is inserted into the opening of the main pipe from the outside;
A hook member that includes a hole through which the cylindrical member is inserted, is disposed between a locking surface formed on an outer periphery of the cylindrical member and the main pipe, and covers the periphery of the opening from the outside;
An inclined portion that abuts on the edge of the opening from the inside of the main pipe, and is screwed into the cylindrical member from the inside of the main pipe, and the flange member is interposed between the inclined portion and the locking surface. And a fixing member that sandwiches the main pipe. The tubular member includes a guide portion that guides the tubular member into the opening,
The inclined portion of the fixing member is formed in a spherical shape, the tip side that contacts the edge of the opening is formed to have a smaller diameter than the outer diameter of the guide portion, and the other end is formed to have a larger diameter than the opening. The branch joint according to claim 1.   The branch according to claim 2, wherein the guide portion includes a same-diameter portion that is formed along the axial direction of the cylindrical member and maintains the same outer diameter, and a tapered portion that is reduced in diameter along the axial direction. Fittings.   The branch joint according to claim 2 or 3, wherein the guide portion and the inclined portion are not in contact with each other in a state where the flange member and the main pipe are sandwiched between the cylindrical member and the fixing member.   The branch joint as described in any one of Claims 1-4 which has the packing which narrows between the said collar member and the said main pipe, and the packing which narrows between the said collar member and the said locking surface.   The branch joint according to any one of claims 1 to 5, wherein the flange member is formed in a shape that is looser than the outer diameter of the main pipe and substantially follows the outer diameter of the main pipe. The locking surface is formed flat,
The branch joint according to any one of claims 1 to 6, wherein the flange member includes a flat portion that contacts the locking surface or faces the locking surface via a packing. Forming a male screw on the outer periphery of the tubular member;
The branch joint as described in any one of Claims 1-7 which forms the internal thread which can be screwed together with the said external thread in the said fixing member. Forming a female thread on the inner diameter of the cylindrical member;
The branch joint according to any one of claims 1 to 7, wherein the fixing member has a cylindrical shape and a male screw that can be screwed to the female screw is formed on an outer periphery of the fixing member.   The branch joint according to claim 9, wherein a water stop member is provided between the cylindrical member and the cylindrical fixing member and on a main pipe side from a portion where the female screw and the male screw are screwed together.   The branch joint according to any one of claims 1 to 10, wherein the tubular member and the flange member are coupled to each other.

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