JP7597890B2 - Manufacturing method of collective joint, lower connecting pipe, manufacturing method of collective joint - Google Patents

Description

The present invention relates to a joint.

Conventionally, buildings such as apartment buildings and office buildings are equipped with a collective joint system for drainage channels, etc. (see, for example, Patent Documents 1 and 2). For example, the collective joint system includes horizontal pipes that collect wastewater on each floor of the building, vertical pipes that direct the wastewater collected in each horizontal pipe downward, and a collective joint that connects the horizontal pipes and the vertical pipes.

The collective joint includes a joint body formed in a tubular shape, a horizontal pipe connection portion provided on the outer circumferential surface of the joint body, and a swirl vane provided on the inner circumferential surface of the joint body.
The joint body is disposed so that its axis is along the vertical direction. The joint body has an inclined pipe portion below the horizontal pipe connection portion, the outer diameter and the inner diameter of which gradually decrease from the top to the bottom.
At least a portion of the swirl vane is disposed on the inner peripheral surface of the inclined pipe portion. A vertical pipe is connected to an upper end portion and a lower end portion of the joint body. A horizontal pipe is connected to the horizontal pipe connecting portion.

The wastewater that flows into the joint body from the vertical pipes and horizontal pipes connected to the upper end of the joint body hits the upper surface of the swirl vane and flows in a spiral shape along the upper surface of the swirl vane. While the wastewater flows down in a spiral shape inside the joint body of the collective joint, the air inside the joint body flows upward through the space where the wastewater does not flow.
In this way, the collective joint system can improve drainage performance, which is the flow rate of drainage water flowing inside while suppressing the pressure difference generated inside.

JP 2000-096646 A JP 2001-173866 A

The collective joints disclosed in Patent Documents 1 and 2 were formed by casting from cast iron or the like, but recently, instead of casting, collective joints have been formed by injection molding from resin or the like. In this case, since the inclined pipe section is formed as described above, the space above the swirl vanes in the inclined pipe section is formed using a die core, and after the collective joint is formed by injection molding, this core can be moved upward relative to the collective joint and easily removed from the collective joint.
However, even if a core is used to form the space below the swirl vanes within the inclined pipe section, the core cannot be moved upward because it engages with the swirl vanes, and on the other hand, the core cannot be moved downward because the inclined pipe section reduces in diameter as it goes downward, making it difficult to remove the core from the collective joint after the collective joint has been formed by injection molding.

The present invention was made in consideration of these problems, and aims to provide a collective joint that improves drainage performance by ensuring a large space below the swirl vanes in the inclined pipe section when the collective joint is formed by injection molding.

In order to solve the above problems, the present invention proposes the following means.
The collective joint of the present invention comprises a joint body formed in a tubular shape and arranged with its axis along the vertical direction, and swirl vanes provided on the inner surface of the joint body, wherein the swirl vanes extend gradually toward a first side in the circumferential direction as they go from top to bottom, and the joint body has an inclined pipe section that gradually reduces in diameter as it goes from top to bottom, and at least a part of the swirl vanes are provided on the inner surface of the inclined pipe section, and the inner surface of the inclined pipe section has a first inner surface that is inclined so as to gradually approach the axis as it goes from top to bottom, and a second inner surface that is arranged in a portion below the swirl vanes and is inclined so as to gradually move away from the axis as it goes from top to bottom.
The portion below the swirl vane referred to here does not only mean a portion that is positioned below any portion of the swirl vane, but also a portion that is positioned below one portion of the swirl vane but not below another portion of the swirl vane.

According to this invention, the first inner surface of the inclined pipe section is inclined so as to gradually move away from the axis as it goes from the bottom to the top. Therefore, the first inner surface can be formed, for example, using a first core of a mold, and after the collective joint is formed by injection molding, the first core can be moved upward relative to the collective joint to remove the first core from the collective joint. Also, the second inner surface of the inclined pipe section is disposed below the swirl vane, and is inclined so as to gradually move away from the axis as it goes downward. Therefore, the second inner surface can be formed, for example, using a second core of a mold, and after the collective joint is formed by injection molding, the second core can be moved downward relative to the collective joint to remove the second core from the collective joint.

In this way, the second inner surface, which is part of the inner surface of the inclined pipe section and is positioned below the swirl vanes, can be formed using the second core, thereby ensuring a wide space below the swirl vanes within the inclined pipe section.
For example, when wastewater flows into the collective joint, the wastewater hits the surface of the swirl vane facing the first side in the circumferential direction and flows in a spiral shape. The space below the swirl vane makes it difficult for the flow of wastewater to be obstructed, thereby improving the drainage performance of the collective joint.

In addition, in the above-mentioned collective joint, at least a portion of the outer peripheral surface of the inclined pipe section arranged radially outside the second inner surface may be inclined so as to gradually move away from the axis as it goes from top to bottom.
According to this invention, the radial thickness of the inclined tube section arranged between the second inner surface and at least a portion of the outer peripheral surface of the inclined tube section arranged radially outside the second inner surface can be reduced, thereby preventing sink marks or the like from occurring in this portion formed by injection molding, which would result in molding defects.

In addition, in the above-mentioned collective joint, the inner circumferential surface of the inclined pipe portion may have a third inner surface extending radially outward from an end of the second inner surface on the second circumferential side and facing the second side.
According to this invention, the first inner surface and the second inner surface of the inclined pipe portion can be connected by the third inner surface.

When the collective joint of the present invention is formed by injection molding, it is possible to ensure a large space below the swirl vanes in the inclined pipe section, thereby improving drainage performance.

FIG. 1 is a side view, with a portion thereof cut away, of a group joint system in which a group joint according to one embodiment of the present invention is used. FIG. 2 is a perspective view showing a part of a lower connecting pipe of the same collective joint broken away. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 3. 4 is a cross-sectional view taken along line VV in FIG. 3. 6 is a cross-sectional view taken along line VI-VI in FIG. FIG. 4 is a cross-sectional view of a mold for forming the lower connecting pipe by injection molding. FIG. 7 is a cross-sectional view of a lower connecting pipe of a collective joint according to another embodiment of the present invention, which corresponds to the cross-sectional view shown in FIG. 6 . FIG. 10 is a cross-sectional view showing a state in which the lower connecting pipe shown in FIG. 9 is connected to a vertical pipe. 1 is a cross-sectional view showing a lower connecting pipe and a vertical pipe that constitute a collective joint system of a first modified example of the present invention. FIG. A cross-sectional view showing a lower connecting pipe and a vertical pipe that constitute a collective joint system of a second modified example of the present invention. A cross-sectional view showing a lower connecting pipe and a vertical pipe that constitute a collective joint system of a third modified example of the present invention. A cross-sectional view showing a lower connecting pipe and a vertical pipe that constitute a collective joint system of a fourth modified example of the present invention.

Hereinafter, a group joint system in which one embodiment of a group joint according to the present invention is used will be described with reference to Figs. 1 to 8 .
As shown in Fig. 1, this collective joint system 1 is used for drainage of a building 101. The collective joint system 1 is arranged on each floor through a slab penetration hole 102a formed in a floor slab 102 of the building 101. Note that Fig. 1 shows a simplified configuration of a lower connecting pipe 19, which will be described later.

The collective joint system 1 comprises a collective joint 11, a vertical pipe 46, and a horizontal pipe 48.
The joint assembly 11 includes a joint body 16 and a horizontal pipe connection portion 41. The joint body 16 is formed in a cylindrical shape and is disposed so that an axis O is aligned in the vertical direction. Hereinafter, the circumferential direction X of the joint body 16 (see FIG. 3 ) will be simply referred to as the circumferential direction X.
The joint body 16 includes an upper connecting pipe 17 and a lower connecting pipe 19 connected to the upper connecting pipe 17 via an intermediate pipe 18 .
A horizontal pipe connecting portion 41 is fixed to the outer circumferential surface of the upper connecting pipe 17. In the present embodiment, a plurality of horizontal pipe connecting portions 41 are provided on the outer circumferential surface of the upper connecting pipe 17. A horizontal pipe 48 is connected to the horizontal pipe connecting portion 41.
A damming plate 22 is fixed to the inner peripheral surface of the upper connecting pipe 17. The damming plate 22 prevents wastewater from flowing back into the horizontal pipe 48.
The upper connecting pipe 17 is made of polyvinyl chloride resin or the like.

A vertical pipe connection part 23 is attached to the upper end part of the upper connecting pipe 17. The vertical pipe connection part 23 is provided with a first swirl vane 24. The first swirl vane 24 is disposed at a position corresponding to the horizontal pipe 48 in the up-down direction.
A vertical pipe 46 is connected to the vertical pipe connecting portion 23. The outer diameter of the vertical pipe 46 is smaller than the inner diameter of the upper connecting pipe 17.

The intermediate pipe 18 and the lower connecting pipe 19 are disposed below the horizontal pipe connecting portion 41 .
The intermediate pipe 18 is preferably made of a polyvinyl chloride resin, and contains a resin composition containing a polyvinyl chloride resin and thermally expandable graphite. That is, the intermediate pipe 18 is produced by molding the resin composition. Usually, the intermediate pipe 18 is produced by extrusion molding the resin composition.
The intermediate tube 18 may have a single-layer structure in which the entire intermediate tube 18 is made of a resin composition, or may have a multi-layer structure made of multiple layers. In the case of a multi-layer structure, any one of the layers may be formed from a resin composition. For example, when the intermediate tube 18 has a three-layer structure consisting of a surface layer, an intermediate layer, and an inner layer, the intermediate layer may be formed from a resin composition, and the surface layer, the intermediate layer, and the inner layer may contain a heat absorbing agent.
In addition, in the case where the intermediate tube 18 does not contain thermally expandable graphite, a sheet-shaped fire-resistant material containing thermally expandable graphite may be wrapped around the outer surface of the intermediate tube 18 or the outer surface of the sound-insulating material covering the intermediate tube 18, and the fire-resistant material may be embedded in the slab through hole 102a.

As an example, a single-layer structure can be used that is made of a resin composition containing 1 to 20 parts by weight of thermally expandable graphite per 100 parts by weight of polyvinyl chloride resin. Alternatively, a three-layer structure can be used that is made of a thermally expandable fire-resistant layer made of a resin composition containing 1 to 20 parts by weight of thermally expandable graphite per 100 parts by weight of polyvinyl chloride resin, and a coating layer of a polyvinyl chloride resin composition that does not contain thermally expandable graphite that covers the inner and outer surfaces of the thermally expandable fire-resistant layer.

When the intermediate tube 18 has a single-layer structure, if the amount of thermally expandable graphite is less than 1 part by weight, sufficient thermal expansion may not be obtained during combustion, and the desired fire resistance may not be obtained. If the amount exceeds 20 parts by weight, the graphite may expand too much when heated, and may not be able to maintain its shape, causing residue to fall out of the slab through-hole 102a, resulting in reduced fire resistance.

When the intermediate tube 18 has a multi-layer structure, the resin composition containing the thermally expandable fire-resistant material is not particularly limited, but is preferably one containing 1 to 20 parts by weight of thermally expandable graphite per 100 parts by weight of polyvinyl chloride resin. The content of the thermally expandable graphite is more preferably 4 to 18 parts by weight, and even more preferably 6 to 16 parts by weight.
Furthermore, if the intermediate tube 18 is present throughout the entire slab through hole 102a, even if the content of thermally expandable graphite is relatively high at 15 parts by weight or more and the residue is brittle, the residue will block the entire slab through hole 102a, and the residue after thermal expansion will be retained within the floor slab 102, making it less likely to fall off.

When the intermediate layer contains thermally expandable graphite, the intermediate layer is black in color, and therefore it is preferable that the surface layer and the inner layer contain a colorant other than black so as to be distinguishable from the intermediate layer.
The thickness of the surface layer and the inner layer is preferably 0.3 mm to 3.0 mm, and more preferably 0.6 mm to 1.5 mm. If the thickness of the coating layer is 0.3 mm or more, the mechanical strength of the pipe can be sufficiently ensured, and if it is 3.0 mm or less, the decrease in fire resistance can be suppressed.
Moreover, it is preferable that the intermediate tube 18 satisfies the performance requirements set forth in JIS K6741.
That is, if the amount of thermally expandable graphite is less than 1 part by weight, sufficient thermal expansion is not obtained during combustion, and the desired fire resistance may not be obtained. If the amount of thermally expandable graphite is more than 20 parts by weight, the graphite may expand too much when heated, and may not be able to maintain its shape, causing residues to fall off from the slab through-holes 102a, resulting in a decrease in fire resistance.

The thermally expandable graphite used in the present embodiment can be, for example, a crystalline compound obtained by subjecting powder of natural scaly graphite, pyrolytic graphite, kish graphite, or the like to an acid treatment using an inorganic acid and a strong oxidizing agent to insert the inorganic acid between the layers of the graphite, and then adjusting the pH.
As the inorganic acid, concentrated sulfuric acid, nitric acid, selenic acid, etc. can be used. As the strong oxidizing agent, concentrated nitric acid, perchloric acid, perchlorates, permanganates, dichromates, hydrogen peroxide, etc. can be used.

By adjusting the pH, it is possible to use thermally expandable graphite that is a crystalline compound that maintains the layered carbon structure and has a pH adjusted to 1.5 to 7.0, and thermally expandable graphite with a 1.3-fold expansion temperature of 180°C to 280°C.

If the pH of the thermally expandable graphite is less than 1.5, the acidity is too strong and the molding equipment is likely to corrode, whereas if the pH exceeds 7.0, the effect of promoting the carbonization of the polyvinyl chloride resin is weakened, and sufficient fire resistance may not be obtained.
The particle size of the thermally expandable graphite is not particularly limited, but may be, for example, in the range of 100 to 400 μm, and preferably in the range of 120 to 350 μm.

Additives such as stabilizers, inorganic fillers, flame retardants, lubricants, processing aids, impact modifiers, heat resistance improvers, antioxidants, light stabilizers, UV absorbers, pigments, plasticizers, and thermoplastic elastomers may be added to the resin composition constituting the intermediate tube 18 as necessary, to the extent that the purpose of this embodiment is not hindered.

A second swirl vane may be provided on the inner peripheral surface of the intermediate pipe 18. The upper end of the intermediate pipe 18 is fitted inside the lower end of the upper connecting pipe 17. The connection portion between the upper connecting pipe 17 and the intermediate pipe 18 is joined by, for example, an adhesive or the like.
1, in this embodiment, the connection portion between the upper connecting pipe 17 and the intermediate pipe 18 is disposed in a slab penetration hole 102a of the floor slab 102. The slab penetration hole 102a is filled with mortar 103. However, this is not limited thereto, and the lower end of the upper connecting pipe 17 and the upper end of the intermediate pipe 18 may be located above the upper surface of the floor slab 102.

The intermediate tube 18 may be omitted.
In this case, the upper connecting pipe 17 and the lower connecting pipe 19 are directly connected. When the connecting pipe portion 31 at the upper end of the lower connecting pipe 19 is a socket, the lower end of the upper connecting pipe 17 is made into a spigot and inserted into the lower connecting pipe 19. When the connecting pipe portion 31 at the upper end of the lower connecting pipe 19 is a spigot, the lower end of the upper connecting pipe 17 is made into a spigot and the lower connecting pipe 19 is inserted into this lower end.
In these cases, the above-mentioned sheet-like fireproof material (hereinafter also referred to as fireproof sheet) can be wrapped around the connection portion between the upper connecting pipe 17 and the lower connecting pipe 19. In this case, the fireproof sheet is wrapped around the portion of the upper connecting pipe 17 or the lower connecting pipe 19 that is located below the horizontal pipe connection portion 41. When wrapping the fireproof sheet around the lower connecting pipe 19, the outer surface of the lower connecting pipe 19 in the area where the third swirl vane 34 is present is recessed (recess 32e) as described below, and it is difficult to wrap the fireproof sheet around this area. Therefore, it is preferable to wrap the fireproof sheet around the area of the lower connecting pipe 19 where the third swirl vane 34 is not present. On the other hand, if a protrusion 36 described below is provided in this area, the fireproof sheet is supported by the protrusion 36. Therefore, the fireproof sheet may be wrapped around the lower connecting pipe 19 up to the position where the third swirl vane 34 is present.

As shown in Figures 2 and 3, the lower connection pipe 19 includes a connection pipe section 31, an inclined pipe section 32, a lower pipe section (vertical pipe connection section) 33, and a third swirl vane (swirl vane) 34.

The connecting pipe portion 31 is formed in a cylindrical shape and is fitted onto the outside of the lower end portion of the intermediate pipe 18 (see FIG. 1). The connecting pipe portion 31 is joined to the intermediate pipe 18 by, for example, an adhesive or the like.
The inclined pipe section 32 is formed in a cylindrical shape and is formed so that the diameter gradually decreases from the top to the bottom. In other words, the inclined pipe section 32 is formed so that the outer diameter and the inner diameter gradually decrease from the top to the bottom. That is, the inner surface of the inclined pipe section 32, except for the inner surface below the third swirl vane 34, is tapered so as to approach the axis O as it goes downward.
The inclined pipe section 32 is disposed coaxially with the connecting pipe section 31. The upper end section of the inclined pipe section 32 is fixed to the inner circumferential surface of the lower end section of the connecting pipe section 31. The upper end section of the inclined pipe section 32 contacts the lower end section of the intermediate pipe 18 from below the intermediate pipe 18 (see FIG. 1 ).

As shown in Fig. 2, the lower pipe section 33 is formed in a cylindrical shape. The lower pipe section 33 is disposed coaxially with the inclined pipe section 32. The upper end section of the lower pipe section 33 is fixed to the outer circumferential surface of the lower end section of the inclined pipe section 32. As shown in Fig. 1, a vertical pipe 46 is connected to the lower pipe section 33.
Vertical pipes 46 are connected to the upper and lower ends of the joint body 16. The two vertical pipes 46 are arranged coaxially.

The third swirl vane 34 is fixed to a portion of the inner circumferential surface of the inclined pipe section 32 below the connecting pipe section 31. Note that a portion of the third swirl vane 34 may be fixed to the inner circumferential surface of the inclined pipe section 32, and the remaining portion of the third swirl vane 34 may be fixed to the inner circumferential surface of the connecting pipe section 31 or the lower pipe section 33, or the like.
2 and 3, the third swirl vane 34 gradually extends toward the first side X1 in the circumferential direction X as it moves from above to below. To explain in more detail, the surface 34a of the third swirl vane 34 facing the first side X1 gradually extends toward the first side X1 as it moves from above to below. The surface 34b of the third swirl vane 34 facing the second side X2 in the circumferential direction X gradually extends toward the first side X1 as it moves from above to below.
Alternatively, a portion of the underside of the third swirl vane 34 may extend gradually from top to bottom toward the first side X1, and the remaining portion of the underside of the third swirl vane 34 may extend along a horizontal plane.

Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 3. Similarly, Figs. 5 and 6 are cross-sectional views taken along line VV and line VI-VI in Fig. 3. Details of the shapes of the inner and outer peripheral surfaces of the inclined tube portion 32 will be described below.
As shown in FIGS. 2 to 6, the inner circumferential surface of the inclined pipe portion 32 includes a first inner surface 32a, a second inner surface 32b, and a third inner surface 32c.
The first inner surface 32a is disposed in a portion above the third swirl vane 34 and in a portion in the circumferential direction where the third swirl vane 34 is not disposed. The first inner surface 32a is inclined so as to gradually approach the axis O from above toward the bottom. In other words, the first inner surface 32a is inclined so as to gradually move away from the axis O from below toward the top. Note that, when the lower end of the third swirl vane 34 is disposed at the upper end of the inclined pipe section 32, for example, the first inner surface 32a does not need to be formed in the portion above the third swirl vane 34.

The second inner surface 32b is disposed in a lower portion of the third swirl vane 34. As shown in Figures 4 to 6, the second inner surface 32b is inclined so as to gradually move away from the axis O as it goes from the top to the bottom. The second inner surface 32b protrudes below the surface 34b of the third swirl vane 34. The second inner surface 32b protrudes radially inward more than the first inner surface 32a.
2, the third inner surface 32c extends radially outward from an end of the second inner surface 32b on the second side X2 in the circumferential direction. The third inner surface 32c faces the second side X2 and is parallel to the axis O. The third inner surface 32c may be gradually inclined downward so as to face the second side X2 in the circumferential direction X.

As shown in Figures 4 and 7, the outer peripheral surface of the inclined pipe section 32 has a first outer surface 32d (at least a part of the outer peripheral surface of the inclined pipe section). The first outer surface 32d is disposed radially outward of the second inner surface 32b. The first outer surface 32d is inclined so as to gradually move away from the axis O from the top to the bottom. That is, in the cross section shown in Figure 4, the first outer surface 32d and the second inner surface 32b are parallel to each other, and the thickness of the inclined pipe section 32 sandwiched between the first outer surface 32d and the second inner surface 32b is constant. The first outer surface 32d is formed over the entire range corresponding to the second inner surface 32b.
That is, in the cylindrically formed inclined pipe section 32, the inner and outer circumferential surfaces of the portion corresponding to the second inner surface 32b are recessed toward the axis O. A so-called recess is formed in the portion corresponding to the second inner surface 32b of the inclined pipe section 32. In other words, a recess 32e recessed toward the axis O is formed on the outer circumferential surface of the inclined pipe section 32.

As shown in Figures 4 and 7, a plurality of protrusions 36 protruding radially outward are formed on the first outer surface 32d of the inclined pipe section 32. The plurality of protrusions 36 extend in the circumferential direction and are arranged at intervals from one another in the up-down direction. The formation of the protrusions 36 has the effect of improving the strength of the inclined pipe section 32 and suppressing vibrations that occur when the drainage water reaches the third swirl vane 34. Furthermore, as described above, when wrapping a fireproof sheet around the lower connecting pipe 19, it also has the effect of holding the fireproof sheet and soundproof cover provided around the inclined pipe section 32.
The first outer surface 32d may be formed in a part of the range corresponding to the second inner surface 32b.

The connecting pipe section 31, the inclined pipe section 32, the lower pipe section 33, and the third swirl vane 34 that constitute the lower connecting pipe 19 are integrally formed by injection molding of, for example, polyvinyl chloride resin.
The joint body 16 is composed of three members: an upper connecting pipe 17, an intermediate pipe 18, and a lower connecting pipe 19. The joint body may be composed of two or four or more members, or may be integrally composed of a single member.
Moreover, the upper connecting pipe 17 and the lower connecting pipe 19 may be made transparent, so that the connection state of the upper connecting pipe 17, the intermediate pipe 18, and the lower connecting pipe 19 can be visually confirmed from the outside.

A sound-insulating cover may be provided as a sound-insulating measure on the outer peripheral surface of the joint body 16. The sound-insulating cover is formed, for example, of a sheet made of soft polyvinyl chloride, butyl rubber, or polypropylene (PP) resin with a thickness of 0.8 to 2 mm. The sound-insulating cover may be a laminate in which a sound-absorbing layer made of polyester fiber, urethane foam, glass wool, rock wool, or the like with a thickness of 5 to 20 mm is provided on the inside of the above-mentioned sheet.
Also, the recess 32e provided on the outer surface of the inclined tube portion 32 of the lower connecting tube 19 may be filled with the material constituting the sound absorbing layer, and the recess 32e may be eliminated from the outside. This allows the sound insulating cover provided around the lower connecting tube 19 to be supported by the filled material.

Next, a method for manufacturing the lower connecting pipe 19 configured as above will be described.
8, the lower connecting pipe 19 is formed by injection molding using a mold 51. For example, the mold 51 includes a first core 52, a second core 53, a first cavity 54, and a second cavity 55.
In a typical mold, the parting line between the cores is the line L shown in Fig. 8, which is the connection portion between the inclined pipe portion 32 and the lower pipe portion 33 in the lower connecting pipe 19. However, in the mold 51, a recess 52a is formed in the first core 52, and a protrusion 53a corresponding to the recess 52a is formed in the second core 53. The protrusion 53a extends beyond the line L into the recess 52a, forming the third swirl vane 34 between the protrusion 53a and the recess 52a.

The first core 52 forms the surface 34a of the third swirl vane 34 and the first inner surface 32a of the inclined pipe section 32. The convex portion 53a of the second core 53 forms the surface 34b of the third swirl vane 34 and the second inner surface 32b of the inclined pipe section 32.
After the lower connecting pipe 19 is formed in the mold 51, the first core 52 is moved upward relative to the lower connecting pipe 19 to remove the first core 52 from the lower connecting pipe 19. Similarly, the second core 53 is moved downward relative to the lower connecting pipe 19 to remove the second core 53 from the lower connecting pipe 19. The first cavity 54 is moved leftward relative to the lower connecting pipe 19 to remove the first cavity 54 from the lower connecting pipe 19. The second cavity 55 is moved rightward relative to the lower connecting pipe 19 to remove the second cavity 55 from the lower connecting pipe 19.
In this manner, the lower connecting pipe 19 is manufactured by injection molding.

As described above, according to the collective joint 11 of this embodiment, the first inner surface 32a of the inclined pipe section 32 is inclined so as to gradually move away from the axis O as it moves from the bottom to the top. Therefore, the first inner surface 32a is formed using the first core 52 of the mold 51, and after the lower connecting pipe 19 of the collective joint 11 is formed by injection molding, the first core 52 can be moved upward relative to the lower connecting pipe 19 to remove the first core 52 from the lower connecting pipe 19. In addition, the second inner surface 32b of the inclined pipe section 32 is disposed below the third swirl vane 34, and is inclined so as to gradually move away from the axis O as it moves downward. Therefore, the second inner surface 32b is formed using the second core 53 of the mold 51, and after the lower connecting pipe 19 is formed by injection molding, the second core 53 can be moved downward relative to the lower connecting pipe 19 to remove the second core 53 from the lower connecting pipe 19.

In this way, the second inner surface 32b, which is part of the inner surface of the inclined pipe section 32 and is positioned below the third swirl vane 34, can be formed using the second core 53, thereby ensuring a wide space below the third swirl vane 34 within the inclined pipe section 32.
When wastewater flows into the collecting joint 11, the wastewater flows in a spiral shape as it hits the surface 34a of the third swirl vane 34 and swirls. The space below the third swirl vane 34 makes it difficult for the flow of wastewater to be obstructed, thereby improving the drainage performance of the collecting joint 11.

The first outer surface 32d disposed radially outward of the second inner surface 32b is inclined so as to gradually move away from the axis O as it goes from top to bottom. This makes it possible to reduce the radial thickness of the inclined tube portion 32 disposed between the second inner surface 32b and the first outer surface 32d, and to suppress molding defects due to sink marks or the like occurring in this portion formed by injection molding.
The inner circumferential surface of the inclined pipe portion 32 has a third inner surface 32c. Therefore, the first inner surface 32a and the second inner surface 32b of the inclined pipe portion 32 can be connected by the third inner surface 32c.

The surfaces 34a, 34b of the third swirl vane 34 each extend gradually from top to bottom toward the first side X1. This allows the thickness of the third swirl vane 34 to be thinned, preventing sink marks and other defects in this part formed by injection molding, which can lead to molding defects. This also ensures a wide space below the third swirl vane 34 within the inclined pipe section 32, further improving the drainage performance of the collective joint 11.

Although one embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and changes, combinations, deletions, etc. of the configuration are also included within the scope that does not deviate from the gist of the present invention.
For example, in the above embodiment, the outer circumferential surface of the inclined tube portion 32 arranged radially outward of the second inner surface 32b may have a flat shape along the axis O, or the like.
In addition, the surface 34a or the surface 34b of the third swirl vane 34 may not be a flat surface, but may be a curved surface that curves upward or downward. Furthermore, the surface 34a or the surface 34b may have continuous or discontinuous convex or concave portions formed thereon.
In the above embodiment, the protrusions 36 arranged on the radially outer side of the second inner surface 32b extend in the circumferential direction X and are arranged spaced apart from each other in the up-down direction. However, the protrusions 36 may extend in the up-down direction (pipe axis direction), or both the protrusions 36 extending in the circumferential direction X and the protrusions 36 extending in the up-down direction may be provided.

The connecting pipe portion 31 and the lower pipe portion 33 are sockets, but may be spigots.
When the connecting pipe portion 31 is a spigot, the intermediate pipe 18 can be omitted as described above, and the connecting pipe portion 31 can be inserted into the lower end (receptacle) of the upper connecting pipe 17 .
When the lower pipe portion 33 is a spigot, it can be configured as in a lower connecting pipe 19A according to another embodiment shown in Figures 9 and 10. In this lower connecting pipe 19A, the upper end of a vertical pipe 46A located below the collective joint 11 serves as a socket 46a, and the lower pipe portion 33 is inserted into the socket 46a. In the illustrated example, the diameter (outer diameter, inner diameter) of the lower pipe portion 33 is equal to the diameter of the lower end of the inclined pipe portion 32.

As shown in FIG. 10, when the upper end of the vertical pipe 46A is a receiving port 46a, a rubber ring 46b that enhances water-stopping properties can be provided inside the receiving port 46a. In the example shown, the inner diameter of the receiving port 46a is larger than the outer diameter of the lower pipe section 33. The rubber ring 46b is fitted into the receiving port 46a from the inside, and is fitted into the lower pipe section 33 from the outside. In other words, the rubber ring 46b is sandwiched between the receiving port 46a and the lower pipe section 33. This allows the rubber ring 46b to exert its water-stopping properties.

However, in the lower connecting pipe 19A, for example, due to unexpected movement of the vertical pipe 46A and the lower connecting pipe 19, there is a risk that the rubber ring 46b will fit onto the outer circumferential surface of the inclined pipe section 32 instead of the outer circumferential surface of the lower pipe section 33. This type of unexpected movement is caused, for example, by the vertical pipe 46A moving due to thermal expansion and contraction, or by a worker making an installation mistake.
Here, when the rubber ring 46b is fitted to the outer peripheral surface of the inclined pipe section 32, there is a risk that the rubber ring 46b will be located at the height of the recess 32e of the lower connecting pipe 19 caused by the third swirl vane 34. In this case, a gap will be created between the rubber ring 46b and the lower pipe section 33, compromising the water-stopping effect of the rubber ring 46b.
Therefore, a means (hereinafter, referred to as a restricting means 60) is provided to restrict the relative movement between the vertical pipe 46A and the lower connecting pipe 19. This restricts the rubber ring 46b from overlapping with the recess 32e, and ensures the waterproofing effect of the rubber ring 46b.

Specific examples of the regulating means 60 are shown in Figures 11 to 14 below.

The restricting means 60A shown in FIG. 11 is provided on the lower connecting pipe 19B. The restricting means 60A is provided at the connection between the inclined pipe section 32 and the lower pipe section 33 on the lower connecting pipe 19B. In other words, the restricting means 60A is located below the height of the recess 32e. The restricting means 60A is a protrusion that protrudes radially outward. In the illustrated example, the restricting means 60A is provided over the entire circumference in the circumferential direction X. In this case, when an unexpected movement such as that described above is about to occur, the upper end of the vertical pipe 46A comes into contact with the lower surface of the restricting means 60A, and further movement is restricted.

The restricting means 60C shown in FIG. 12 is provided on the vertical tube 46B. The restricting means 60C is provided at the upper end of the vertical tube 46B. The restricting means 60C is a protrusion that protrudes radially inward. In the illustrated example, the restricting means 60C is provided over the entire circumference in the circumferential direction X. The inner diameter of the restricting means 60C is equal to the outer diameter of the lower tube section 33. In this case, when an unexpected movement such as that described above is about to occur, the restricting means 60C comes into contact with the lower end of the inclined tube section 32, and further movement is restricted.

The restricting means 60D shown in FIG. 13 is provided on the vertical tube 46C. In this modified example, the shape of the receiving port 46a is different from the other modified examples. That is, the inner diameter of the receiving port 46a in this modified example is equal to the outer diameter of the lower tube portion 33. The inner peripheral surface of the receiving port 46a is provided with an annular recess 46c extending in the circumferential direction X. The rubber ring 46b is fitted into the recess 46c. The restricting means 60D is formed by the upper end of the vertical tube 46C. In this case, when an unexpected movement as described above is about to occur, the restricting means 60D (upper end of the vertical tube 46C) comes into contact with the lower end of the inclined tube portion 32, as in the modified example shown in FIG. 12, and further movement is restricted.

The restricting means 60E shown in FIG. 14 is provided on the rubber ring 46b. The restricting means 60E is provided on the lower end of the rubber ring 46b. The restricting means 60E is a protrusion that protrudes radially inward. In the illustrated example, the restricting means 60E is provided over the entire circumference in the circumferential direction X. The inner diameter of the restricting means 60E is equal to or smaller than the outer diameter of the lower tube portion 33. In this case, when an unexpected movement as described above is about to occur, the restricting means 60E contacts the lower end of the lower tube portion 33, and further movement is restricted. In this case, it is preferable that the distance L1 from the restricting means 60E to the lower end of the lower tube portion 33 is shorter than the distance L0 from the upper end of the vertical tube 46A to the recess 32e (L1<L0). The restricting means 60E may also be formed by a step portion 46d provided at the base end of the receiving port 46a, or may be provided as a protrusion inside the receiving port 46a. In these cases, the inner diameter of the receiving port 46a may be equal to the outer diameter of the lower tube portion 33, as in the vertical tube 46C shown in FIG. 13.

The joint assembly 11 does not necessarily have to include the vertical pipe connection portion 23 and the horizontal pipe connection portion 41 .
The position at which the swirl vane is provided within the joint body 16 is not particularly limited, and may be, for example, a position equivalent to the horizontal pipe connection portion 41 in the vertical direction.
The joint body 16 has been described as being formed in a circular tubular shape. However, the shape of the joint body is not limited to this, and the joint body may be formed in an elliptical tubular shape, a square tubular shape, or the like.

11 Collective joint 16 Joint body 32 Inclined pipe section 32a First inner surface 32b Second inner surface 32c Third inner surface 32d First outer surface (at least a part of the outer circumferential surface of the inclined pipe section)
34 Third swirl blade (swirl blade)
O Axis X Circumferential direction X1 First side X2 Second side

Claims (9)

A collective joint to be placed in a slab penetration hole formed in a floor slab of a building,
A resin joint body formed in a tubular shape and arranged with its axis along the vertical direction;
A swirl vane is provided on an inner peripheral surface of the joint body;
Equipped with
The swirl vane extends gradually toward a first side in a circumferential direction from above to below, and has an upper surface facing the first side and a lower surface facing a second side in the circumferential direction,
The joint body includes an upper connecting pipe having a horizontal pipe connecting portion on its outer peripheral surface and a socket or spigot at its lower end, and a lower connecting pipe having an inclined pipe portion whose diameter gradually decreases from top to bottom and whose upper end is formed by injection molding into a socket or spigot that is connected to the lower end of the upper connecting pipe, the lower connecting pipe being made of polyvinyl chloride resin,
At least a portion of the swirl vane is integrally formed on the inner circumferential surface of the inclined pipe portion by injection molding,
The inner circumferential surface of the inclined tube portion is
A first inner surface that is inclined so as to gradually approach the axis line from above toward below;
a second inner surface disposed in a portion below the swirl vanes;
a third inner surface extending radially outward from an end of the second inner surface on a second side in a circumferential direction and facing the second side;
having
A recess is provided on an outer peripheral surface of the inclined tube portion at a portion corresponding to the second inner surface, and the third inner surface is inclined toward the second side as it is parallel to the axis or extends downward,
A collective joint in which a sound-insulating cover made of soft polyvinyl chloride, butyl rubber, or polypropylene resin is provided on the outer peripheral surface of the joint body. a thermally expandable fireproof material is provided on an outer surface of the upper connecting pipe at a position below the horizontal pipe connecting portion;
The assembly joint of claim 1 , wherein the thermally expandable refractory material is disposed within the slab penetration hole. The assembly joint according to claim 1 or 2, wherein the second inner surface is inclined so as to gradually move away from the axis as it goes from the top to the bottom. The assembly joint according to any one of claims 1 to 3, in which a sound absorbing layer made of polyester fiber, urethane foam, glass wool, or rock wool and having a thickness of 5 to 20 mm is provided on the inside of the sound insulation cover. A method for manufacturing a lower connecting pipe having a connecting pipe portion which is a socket or a spigot at an upper end, an inclined pipe portion at a lower part of the connecting pipe portion, a swirl vane having an upper surface and a lower surface on an inner surface of the inclined pipe portion, a first inner surface, and a second inner surface, the second inner surface having a recess on an outer side, and a lower pipe portion which is a socket or a spigot at a lower end of the inclined pipe portion,
It is formed by injection molding of polyvinyl chloride resin using a mold,
The mold is
a first core forming the first inner surface and an upper surface of the swirl vane;
a second core forming the second inner surface and a lower surface of the swirl vane;
a first cavity forming one portion of an outer surface of the inclined tube portion;
a second cavity that forms the other part of the outer surface of the inclined tube portion;
The second cavity forms the recess.
Manufacturing method of the lower connecting pipe. the first core is moved upward in the tube axial direction to be removed from the connecting pipe portion;
the second core is moved downward in the tube axis direction and removed from the lower tube portion;
The first cavity is moved in a direction perpendicular to the tube axis and to the left in a side view of the lower surface of the swirl vane,
The second cavity is moved in a direction perpendicular to the tube axis and to the right in a side view of the lower surface of the swirl vane.
The method for manufacturing the lower connecting pipe according to claim 5 . a protrusion between the inclined tube section and the lower tube section, the first cavity forming one portion of an outer surface of the protrusion,
The second cavity forms the other portion of the outer surface of the projection.
The method for manufacturing the lower connecting pipe according to claim 5 or 6. a third inner surface connecting the first inner surface and the second inner surface,
The method for manufacturing a lower connecting pipe according to any one of claims 5 to 7, wherein the third inner surface is formed by the first core. an upper connecting pipe having a horizontal pipe connecting portion on an outer peripheral surface and a socket or a spigot at a lower end;
A lower connecting pipe manufactured by the manufacturing method according to any one of claims 5 to 8;
A manufacturing method of a collective joint comprising:
an upper end of the lower connecting pipe and a lower end of the upper connecting pipe are connected;
A thermally expandable fireproof material is provided on the outer surface at a position below the horizontal pipe connection portion.
A method for manufacturing a joint.

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