Drain pipe joint

Abstract

To provide a drain pipe joint capable of improving its transportability.SOLUTION: The drain pipe joint for connecting a toilet bowl on the upstream side to a horizontal drain pipe on the downstream side includes a downstream pipe connected to the horizontal drain pipe side, an upstream pipe connected to the toilet bowl side, and a joint pipe connecting the downstream pipe to the upstream pipe, the joint pipe having a first connection pipe part connected to the upstream pipe, a second connection pipe part connected to the downstream pipe, and a joint pipe part provided between the first connection pipe part and the second connection pipe part and having a smooth inner face and a constant inner diameter.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] FIELD OF THE INVENTION Aspects of the present invention generally relate to drain pipe fittings. [Background technology]

[0002] A drain pipe is provided downstream of the toilet to drain water and waste from the toilet. The drain pipe may be, for example, a horizontal drain pipe that extends horizontally. For example, multiple toilets connected together in a public facility are connected to the horizontal drain pipe.

[0003] The toilet bowl and horizontal drain pipe are connected by a drain pipe joint. Water, waste, etc. are drained from the toilet bowl through the drain pipe joint into the horizontal drain pipe downstream. There is a demand for improved transportability of water and waste downstream. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2017-082481 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made based on the recognition of such problems, and aims to provide a drainage pipe joint that can improve transportability. [Means for solving the problem]

[0006] The first invention is a drain pipe fitting that connects an upstream toilet and a downstream horizontal drain pipe, and is characterized in that it comprises a downstream pipe connected to the horizontal drain pipe, an upstream pipe connected to the toilet, and a coupling pipe that connects the downstream pipe and the upstream pipe, wherein the coupling pipe has a first connecting pipe section that is connected to the upstream pipe, a second connecting pipe section that is connected to the downstream pipe, and a coupling pipe section between the first connecting pipe section and the second connecting pipe section that has a smooth inner surface and a constant inner diameter.

[0007] With this drain pipe joint, the inner surface of the joint pipe section is smooth and the inner diameter is constant, which makes it possible to prevent a loss of force to flush away waste and a weakening of water force. Therefore, it is easier to transport water and waste within the drain pipe joint and the horizontal drain pipe downstream, improving transportability.

[0008] A second invention is a drainage pipe joint according to the first invention, characterized in that the joint pipe is flexible and has a deformation suppression portion that suppresses changes in the diameter of the joint pipe portion.

[0009] According to this drain pipe joint, the joint pipe is flexible, making it easy to connect the toilet and the horizontal drain pipe using the drain pipe joint, improving workability. Furthermore, by providing a deformation suppression section, even if the joint pipe is flexible, it is possible to suppress changes in the inner diameter of the joint pipe section, and the inner diameter of the joint pipe section can be maintained constant. This allows high transportability to be maintained even if the joint pipe is bent depending on the construction situation.

[0010] The third invention is a drainage pipe fitting according to the second invention, characterized in that the deformation suppression portion is provided in the second connecting pipe portion and suppresses the formation of a step between the fitting pipe and the downstream pipe that narrows the flow path downstream when the fitting pipe and the downstream pipe are connected.

[0011] According to this drainage pipe joint, the deformation suppression portion can suppress changes in the diameter of the joint pipe, while suppressing a step at the connection portion between the joint pipe and the downstream pipe, thereby further improving transportability.

[0012] A fourth invention is a drainage pipe fitting according to the second or third invention, characterized in that the deformation suppression portion has a first extension portion extending from the downstream end of the fitting pipe portion toward the outside of the fitting pipe, a connection portion extending downstream from the outer end of the first extension portion, and a second extension portion extending from the downstream end of the connection portion toward the inside of the fitting pipe, and the second connection pipe portion has a connecting tubular portion extending downstream from the inner end of the second extension portion, and the inner diameter of the connecting tubular portion is larger than the inner diameter of the fitting pipe portion.

[0013] According to this drainage pipe joint, the deformation suppression portion has the first and second extension portions and the connecting portion, so that when force is applied to the joint pipe portion, the deformation suppression portion can expand and contract in the axial direction. This suppresses changes in the inner diameter of the joint pipe portion. Furthermore, because the inner diameter of the connecting tube portion is larger than the inner diameter of the joint pipe portion, when the downstream pipe is inserted into the connecting tube portion, the formation of a step between the inner surface of the downstream pipe and the inner surface of the joint pipe portion is suppressed.

[0014] The fifth invention is a drainage pipe fitting, characterized in that, in any one of the first to third inventions, the upstream pipe has a downstream end portion having a tapered portion whose inner surface slopes outward from the upstream pipe as it approaches the downstream side.

[0015] According to this drainage pipe joint, when the upstream pipe is inserted into the joint pipe, the step formed between the inner surface of the upstream pipe and the inner surface of the joint pipe portion can be reduced.

[0016] A sixth invention is a drainage pipe fitting according to the fifth invention, characterized in that the downstream end of the tapered portion is provided with a folded portion extending toward the outside of the upstream pipe.

[0017] According to this drainage pipe joint, the strength of the downstream end of the upstream pipe can be improved by providing a folded portion. [Effects of the Invention]

[0018] According to an aspect of the present invention, a drainage pipe joint that can improve transportability is provided. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a perspective view illustrating a toilet unit provided with a drainage pipe joint according to an embodiment. [Figure 2] FIG. 2 is a perspective view illustrating a toilet unit provided with a drain pipe joint according to the embodiment. [Figure 3] FIG. 3 is a cross-sectional view illustrating a part of a toilet unit provided with a drain pipe joint according to an embodiment. [Figure 4] FIG. 4 is a perspective view illustrating a drainage pipe joint according to an embodiment. [Figure 5] FIG. 5 is a cross-sectional view illustrating a drainage pipe joint according to an embodiment. [Figure 6] FIG. 6 is a cross-sectional view illustrating a joint pipe of a drainage pipe joint according to an embodiment. [Figure 7] 7(a) and 7(b) are schematic cross-sectional views illustrating steps and protrusions provided on a pipe. [Figure 8] FIG. 8 is a cross-sectional view illustrating the downstream pipe of the drainage pipe joint according to the embodiment. [Figure 9] FIG. 9 is a cross-sectional view illustrating the connection between the downstream pipe and the joint pipe of the drainage pipe joint according to the embodiment. [Figure 10] FIG. 10 is a cross-sectional view illustrating an upstream pipe of a drainage pipe joint according to an embodiment. [Figure 11] FIG. 11 is a cross-sectional view illustrating the connection between an upstream pipe and a joint pipe of a drainage pipe joint according to an embodiment. [Figure 12] 12(a) and 12(b) are schematic views illustrating adjustment of the position of the drain pipe joint according to the embodiment. [Figure 13] 13(a) to 13(e) are schematic views illustrating rotation of the upstream pipe of the drainage pipe joint according to the embodiment. [Figure 14] 14(a) and 14(b) are cross-sectional views illustrating adjustment of the position of the drain pipe joint according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, like components are designated by like reference numerals and detailed descriptions thereof will be omitted where appropriate. 1 and 2 are perspective views illustrating a toilet unit provided with a drain pipe joint according to an embodiment. In Fig. 2, a toilet bowl 220 and a part of a lining 250 are omitted. The toilet unit 210 according to this embodiment comprises a Western-style seated flush toilet (hereinafter, for convenience of explanation, simply referred to as "toilet") 220 and a drain pipe joint 100 (see FIG. 2).

[0021] In this specification, the upper, lower, front, rear, left side, and right side as seen from a user sitting on the toilet seat provided on the toilet bowl 220 during normal use will be referred to as "upper," "lower," "front," "rear," "left side," and "right side," respectively.

[0022] As shown in FIG. 1, the toilet bowl 220 is provided in front of a panel 251. For example, the panel 251 is the front plate of a lining 250 in which a drain pipe and the like are provided. The lining 250 has, for example, a panel 251 and an upper plate 252. A wall 310 of the toilet room is located behind the lining 250. For example, the lining 250 stores at least a portion of the drain pipe fitting 100, the horizontal drain pipe 260, and the like within the space defined by the wall 310, the floor 320, the panel 251, and the upper plate 252. Note that the panel 251 does not necessarily have to be the front plate of the lining, and the tray unit does not necessarily have to have a lining.

[0023] The drain pipe joint 100 according to the embodiment is located behind the toilet bowl 220. As shown in Figure 2, the drain pipe joint 100, a horizontal drain pipe 260, and a support 270 are housed inside the lining 250.

[0024] The horizontal drain pipe 260 extends in the left-right direction. The horizontal drain pipe 260 also has a gentle downward slope in the left-right direction. This allows water and waste in the horizontal drain pipe 260 to easily flow downstream along the downward slope.

[0025] The support 270 has two pillars. Between the two pillars 274, the drain pipe joint 100 extends forward from the horizontal drain pipe 260. The drain pipe joint 100 is a tubular member that connects the toilet bowl 220 and the horizontal drain pipe 260 located behind the toilet bowl 220.

[0026] For example, the toilet unit 210 may be a public toilet facility. In such a toilet facility, multiple toilets 220 are arranged side by side. Each toilet 220 is connected to a horizontal drain pipe 260 via a drain pipe joint 100. Because the horizontal drain pipe 260 has a downward slope, the height of the horizontal drain pipe 260 varies in the left-right direction. Therefore, the height at which the drain pipe joint 100 connects to the horizontal drain pipe 260 varies in the left-right direction. For example, the height at which the drain pipe joints 100 connected to adjacent toilets 220 connect to the horizontal drain pipe 260 is different from each other.

[0027] Furthermore, piping such as a tank 273, a flush pipe 272, and a water supply pipe may be provided inside the lining 250. The tank 273 and the flush pipe 272 are provided above the drain pipe joint 100. One end of the flush pipe 272 is connected to the tank 273, and the other end is connected to the toilet 220. The tank 273 stores water, and the stored water is guided to the bowl surface of the toilet 220 via the flush pipe 272.

[0028] FIG. 3 is a cross-sectional view illustrating a part of a toilet unit provided with a drain pipe joint according to an embodiment. In this example, toilet 220 is supported by support 270 in a state where it is floating above floor 320. Toilet 220 discharges water rearward. For example, toilet 220 is a wall-hung toilet. A "wall-hung toilet" does not only refer to a toilet supported on a wall, but also to a toilet supported by support 270 or panel 251. Note that in the embodiment, toilet 220 does not have to be a wall-hung toilet. Toilet 220 has a bowl that receives waste and a pipe portion 225 that is connected to the bowl and extends rearward.

[0029] The drain pipe joint 100 connects the toilet 220 on the upstream side to the horizontal drain pipe 260 on the downstream side. That is, the upstream end (front end) of the drain pipe joint 100 is connected to the pipe section 225 of the toilet 220, and the downstream end (rear end) of the drain pipe joint 100 is connected to the horizontal drain pipe 260. The drain pipe joint 100 forms a downward slope from the toilet 220 to the horizontal drain pipe 260.

[0030] The drain pipe fitting 100 has an upstream pipe 10, a downstream pipe 20, and a joint pipe 30. The upstream pipe 10 is connected to a pipe section 225 of the toilet 220. The downstream pipe 20 is connected to a horizontal drain pipe 260. The downstream pipe 20 is a junction pipe where the flow path formed by the drain pipe fitting 100 merges with the horizontal drain pipe 260. The joint pipe 30 connects the upstream pipe 10 and the downstream pipe 20.

[0031] FIG. 4 is a perspective view illustrating a drainage pipe joint according to an embodiment. FIG. 5 is a cross-sectional view illustrating a drainage pipe joint according to an embodiment. The upstream pipe 10 has a first pipe section 11, a second pipe section 12, and an intermediate pipe section 13. The first pipe section 11 is the upstream part of the upstream pipe 10 and is cylindrical. Note that the cylindrical shape does not necessarily have to be a shape in which the cross section is strictly circular, but may be an ellipse or a nearly circular shape. A flange 17 is provided on the outer periphery of the first pipe section 11. The flange 17 extends outward from the first pipe section 11 when viewed from the central axis of the first pipe section 11.

[0032] As shown in FIG. 3, a portion of the first pipe 11 upstream of the flange 17 is positioned forward of the panel 251. The pipe 225 of the toilet 220 is inserted inside the first pipe 11. Also, as shown in FIG. 2, the flange 17 of the first pipe 11 engages with the fascia 271 of the support 270. The position of the first pipe 11 is fixed relative to the support 270. The up-down, left-right, and front-to-rear positions of the first pipe 11 are regulated by the support 270 (fixing devices such as the fascia 271). The upstream opening of the first pipe 11 is positioned so as to face forward. In other words, the central axis of the first pipe 11 is aligned in the front-to-rear direction. In this way, the first pipe 11 is positioned at a predetermined position determined according to the positions of the toilet 220 and the support 270.

[0033] As shown in FIGS. 4 and 5, the second pipe section 12 is located downstream of the upstream pipe 10 and is cylindrical. The second pipe section 12 extends diagonally rearward when viewed from the first pipe section 11. The second pipe section 12 extends rearward, downward, and laterally (toward the downstream side) from the first pipe section 11 and the intermediate pipe section 13. The downstream opening of the second pipe section 12 is connected to the joint pipe 30. The intermediate pipe section 13 connects the first pipe section 11 and the second pipe section 12. The upstream pipe 10 has a bent shape at the intermediate pipe section 13. As shown in FIG. 3, the intermediate pipe section 13 and the second pipe section 12 are disposed rearward of the panel 251.

[0034] The first pipe portion 11, the second pipe portion 12, and the intermediate pipe portion 13 are integrally formed. The material of the upstream pipe 10 is not particularly limited, but for example, hard vinyl chloride can be used.

[0035] As shown in Figures 4 and 5, the downstream pipe 20 has a horizontal pulling pipe section 21 and a junction pipe section 22. The horizontal pulling pipe section 21 is cylindrical and extends in the left-right direction. In this example, the left and right diameters of the horizontal pulling pipe section 21 are larger than the diameter of the center section. A horizontal drainage pipe 260 (see Figure 2) is inserted into each of the openings at the left and right ends of the horizontal pulling pipe section 21.

[0036] The junction pipe section 22 is cylindrical and extends obliquely forward from the outer peripheral side surface of the lateral drawing pipe section 21, and is connected to the lateral drawing pipe section 21. The junction pipe section 22 extends forward, upward, and sideways (toward the upstream side) from the lateral drawing pipe section 21. The upstream opening of the junction pipe section 22 is connected to the joint pipe 30.

[0037] The horizontal drawing pipe section 21 and the junction pipe section 22 are integrally formed. The material of the horizontal drawing pipe section 21 and the junction pipe section 22 is not particularly limited, but for example, hard vinyl chloride can be used.

[0038] As shown in FIGS. 4 and 5, the joint pipe 30 has a first connecting pipe portion 31, a second connecting pipe portion 32, and a joint pipe portion 33.

[0039] The first connecting pipe section 31 is cylindrical and includes an opening on the upstream side of the joint pipe 30. The first connecting pipe section 31 is connected to the upstream pipe 10. As shown in FIG. 5 , the first connecting pipe section 31 overlaps with the second pipe section 12 of the upstream pipe 10 in the radial direction of the joint pipe 30. More specifically, the second pipe section 12 of the upstream pipe 10 is inserted into the first connecting pipe section 31. The inner surface of the first connecting pipe section 31 contacts the outer surface of the second pipe section 12. The inner surface of the first connecting pipe section 31 is covered by the second pipe section 12. As shown in FIG. 4 , for example, a band fastener 41 is provided on the outer surface of the first connecting pipe section 31. The band fastener 41 fastens the first connecting pipe section 31 and the second pipe section 12, thereby fixing the first connecting pipe section 31 and the second pipe section 12 together.

[0040] The second connecting pipe section 32 is cylindrical and includes a downstream opening of the joint pipe 30. The second connecting pipe section 32 is connected to the downstream pipe 20. As shown in FIG. 5 , the second connecting pipe section 32 overlaps with the junction pipe section 22 of the downstream pipe 20 in the radial direction of the joint pipe 30. More specifically, the junction pipe section 22 of the downstream pipe 20 is inserted into the second connecting pipe section 32. The inner surface of the second connecting pipe section 32 contacts the outer surface of the junction pipe section 22. As shown in FIG. 4 , for example, a band fastener 42 is provided on the outer surface of the second connecting pipe section 32. The band fastener 42 fastens the second connecting pipe section 32 and the junction pipe section 22, thereby fixing the second connecting pipe section 32 and the junction pipe section 22.

[0041] The joint pipe 33 is cylindrical and connects the first connecting pipe 31 and the second connecting pipe 32. The joint pipe 33 continues from the downstream end of the first connecting pipe 31 to the upstream end of the second connecting pipe 32.

[0042] The joint pipe 30 (first connecting pipe portion 31, second connecting pipe portion 32, and joint pipe portion 33) has, for example, flexibility. The flexibility of the joint pipe 30 is higher than that of the upstream pipe 10 and higher than that of the downstream pipe 20. The upstream pipe 10 and the downstream pipe 20 do not necessarily have flexibility.

[0043] The first connecting pipe portion 31, the second connecting pipe portion 32, and the joint pipe portion 33 are integrally formed. The materials of the first connecting pipe portion 31, the second connecting pipe portion 32, and the joint pipe portion 33 are not particularly limited, but soft vinyl chloride, for example, can be used.

[0044] FIG. 6 is a cross-sectional view illustrating a joint pipe of a drainage pipe joint according to an embodiment. A pipe (cylinder) has an inner surface and an outer surface that surround a central axis extending in the axial direction. For example, the coupling pipe 30 has an inner surface and an outer surface that surround the central axis 30x. The inner surface and the outer surface are spaced apart radially from the central axis. The radial direction is a direction that is perpendicular to the central axis at each point on the central axis. The direction of the central axis (axial direction) is, for example, the direction in which the upstream or downstream opening of the pipe faces.

[0045] As shown in FIG. 6, the first connecting pipe portion 31 is provided within a range less than a distance L1 from the upstream end 30e of the joint pipe 30 along the central axis 30x. Distance L1 is, for example, 10 mm or more and 30 mm or less. The second connecting pipe portion 32 is provided within a range less than a distance L2 from the downstream end 30f of the joint pipe 30 along the central axis 30x. Distance L2 is, for example, 20 mm or more and 50 mm or less. The length L3 of the joint pipe portion 33 along the central axis 30x is longer than the length of the first connecting pipe portion 31 along the central axis 30x and is longer than the length of the second connecting pipe portion 32 along the central axis 30x. Length L3 is, for example, 30 mm or more and 60 mm or less.

[0046] A protrusion 31p is provided on the inner surface 31i of the first connecting pipe portion 31. The protrusion 31p is pressed against the second pipe portion 12 of the upstream pipe 10. This prevents water from leaking. For example, multiple protrusions 31p are lined up along the direction in which the central axis 30x extends. The outer diameter of the first connecting pipe portion 31 may be constant along the central axis 30x.

[0047] For example, the inner diameter d33 of the joint pipe portion 33 is constant along the direction in which the central axis 30x extends. That is, in a cross section such as that shown in Figure 6 (a cross section including a line on the central axis 30x), the inner surface 33i of the joint pipe portion 33 extends along the direction of the central axis 30x. Note that the diameter may be, for example, the shortest length in a direction passing through the central axis and perpendicular to the central axis (for example, the length of the minor axis if the cross section is elliptical).

[0048] Furthermore, the inner surface 33i of the joint pipe portion 33 is smooth. That is, the inner surface 33i does not need to have any protrusions or steps. For example, the inner surface 33i of the joint pipe portion 33 is smoother than the inner surface 31i of the first connecting pipe portion 31. For example, the inner surface 33i of the joint pipe portion 33 is smoother than the inner surface 32i of the second connecting pipe portion 32. The smooth surface of the pipe is formed, for example, by a curved surface.

[0049] If the inner surface of a fitting has large irregularities or steps, the water flowing through the fitting may hit these irregularities, disrupting the flow and weakening its momentum. Furthermore, in the case of fittings with a variable inner diameter, the water flowing through the fitting may expand in the areas where the inner diameter widens, meaning that some of the water may flow downstream without flushing away the waste inside the fitting. This could result in a loss of power to flush away the waste.

[0050] For example, some conventional joints use bellows-shaped pipes. In bellows-shaped pipes, concave and convex portions are alternately provided on the inner and outer surfaces of the pipe along the central axis of the pipe. In this case, the concave and convex portions can cause a power loss in the water flow.

[0051] In contrast, in the embodiment, the inner surface 33i of the joint pipe portion 33 is smooth and the inner diameter d33 is constant, which makes it possible to prevent a loss of force to flush away waste and a weakening of the water force. Therefore, it becomes easier to transport water and waste within the drain pipe joint 100 and the horizontal drain pipe 260 downstream thereof, and transportability can be improved.

[0052] For example, the outer surface 33e of the joint pipe portion 33 is smooth. The wall thickness of the joint pipe portion 33 may be constant. For example, the outer diameter D33 of the joint pipe portion 33 is constant along the direction in which the central axis 30x extends. The joint pipe portion 33 according to the embodiment does not have to have a shape (for example, a bellows shape) in which multiple convex portions (and multiple concave portions) are aligned along the direction of the central axis.

[0053] For example, in a bellows-shaped pipe, rats and other animals may chew on the convex parts of the pipe. In contrast, the inner surface 33i and the outer surface 33e of the joint pipe portion 33 according to the embodiment are smooth, which can prevent rats from chewing on them.

[0054] With respect to the inner and outer diameters of a pipe, a constant diameter does not necessarily mean that the diameter does not change strictly, but also means that the change in diameter is small and the diameter is substantially constant. A substantially constant diameter may include a case where the diameter changes within a range of, for example, 12 mm or less, preferably 2 mm or less. The difference between the maximum and minimum diameters in a portion where the diameter is substantially constant (e.g., the joint pipe portion 33) is, for example, 12 mm or less, preferably 2 mm or less. For example, a constant diameter may mean that minute steps or protrusions are formed on the surface.

[0055] Furthermore, "smooth" does not necessarily mean that there are no protrusions or steps in the strict sense, but may mean that minute protrusions and steps are formed. For example, a smooth surface may have protrusions and steps with a height of 6 mm or less (or 4 mm or less, or 1.5 mm or less). In other words, a smooth surface does not have protrusions or steps with a height of, for example, more than 6 mm, preferably more than 4 mm, more preferably more than 1.5 mm.

[0056] 6, the central axis 30x of the joint pipe 30 is, for example, linear when not connected to the upstream pipe 10 and the downstream pipe 20. For example, before the joint pipe 30 is connected to the upstream pipe 10 and the downstream pipe 20, the inner diameter and outer diameter of the joint pipe portion 33 are constant along the axial direction.

[0057] As described above, for example, the joint pipe 30 is flexible. In this case, the joint pipe 30 can be deformed so that the central axis 30x is curved. When connecting the toilet 220 and the horizontal drain pipe 260 via the drain pipe joint 100, the joint pipe 30 can be curved as appropriate. For example, when the joint pipe 30 connects the toilet 220 and the horizontal drain pipe 260, the central axis 30x and the inner surface 33i of the joint pipe portion 33 are curved so as to maintain a constant distance between the central axis 30x and the inner surface 33i.

[0058] Because the joint pipe 30 is flexible, the depth and height of the drain pipe joint 100 can be adjusted when connecting the toilet 220 and the horizontal drain pipe 260. That is, for example, the length of the drain pipe joint 100 in the front-to-rear direction and the length in the up-down direction can be adjusted. Also, for example, the height (position in the up-down direction) of the second pipe section 12 and the junction pipe section 22 inserted into the joint pipe 30 can be adjusted. This makes it easier to connect the toilet 220 and the horizontal drain pipe 260 using the drain pipe joint 100, improving workability. For example, it is possible to prevent a decrease in transportability while improving workability.

[0059] 6, the joint pipe 30 has a deformation suppression portion 34 that suppresses changes in the diameter of the joint pipe portion 33. The deformation suppression portion 34 is, for example, a constant diameter maintaining portion that suppresses changes in the inner diameter d33 of the joint pipe portion 33 and maintains it constant.

[0060] For example, if the joint pipe 30 is flexible, there is a risk that the inner diameter of the joint pipe 30 will change when the joint pipe 30 is bent. For example, there is a risk that the joint pipe section 33 will deform due to twisting or the like of the joint pipe 30, causing a change in the inner diameter. In response to this, by providing the deformation suppression section 34, even if the joint pipe 30 is flexible, it is possible to suppress deformation such as twisting of the joint pipe 30, suppress changes in the inner diameter of the joint pipe section 33, and maintain a constant inner diameter d33 of the joint pipe section 33. As a result, high transportability can be maintained even if the joint pipe 30 is bent depending on the construction situation.

[0061] Specifically, in this example, the deformation suppression portion 34 is provided in the second connecting pipe portion 32. As shown in FIG. 6, the second connecting pipe portion 32 has the deformation suppression portion 34 and a connecting tubular portion 32a. The deformation suppression portion 34 is an upstream portion of the second connecting pipe portion 32. The deformation suppression portion 34 continues from the downstream end of the joint pipe portion 33 to the upstream end of the connecting tubular portion 32a. The deformation suppression portion 34 is annular and surrounds the central axis 30x.

[0062] The connecting tubular portion 32a is cylindrical and includes the downstream opening of the joint pipe 30. The inner diameter of the connecting tubular portion 32a is constant. The inner and outer surfaces of the connecting tubular portion 32a are smooth. When the junction pipe portion 22 of the downstream pipe 20 is inserted into the second connecting pipe portion 32 (see FIG. 5), the inner surface of the connecting tubular portion 32a is covered by the junction pipe portion 22. A band fixing device 42 (see FIG. 4) is fixed to the outer surface of the connecting tubular portion 32a.

[0063] In this example, the deformation suppression portion 34 has a folded shape. That is, the shape of the deformation suppression portion 34 extends to the outside of the joint pipe 30 and folds back to the inside of the joint pipe 30 when viewed from the central axis 30x. More specifically, the deformation suppression portion 34 has a first extending portion 34a, a second extending portion 34b, and a connecting portion 34c. The first extending portion 34a extends from the downstream end of the joint pipe portion 32 toward the outside of the joint pipe 30 (in a direction away from the central axis 30x). The connecting portion 34c is continuous with the outer end of the first extending portion 34a and extends downstream. The second extending portion 34b extends from the downstream end of the connecting portion 34c toward the inside of the joint pipe 30 (in a direction approaching the central axis 30x). The connecting tubular portion 32a extends downstream from the inner end of the second extending portion 34b along the direction of extension of the central axis 30x. For example, as shown in FIG. 5, when the joint pipe 30 and the downstream pipe 20 are connected, the junction pipe portion 22 of the downstream pipe 20 is inserted inside the deformation suppression portion 34 and inside the connecting tubular portion 32a.

[0064] In this way, because the deformation suppression section 34 has the first extension section 34a, the second extension section 34b, and the connecting section 34c, the deformation suppression section 34 can expand and contract in the axial direction when force is applied to the joint pipe section 33. For example, the deformation suppression section 34 functions as a margin for expansion and contraction in the axial direction of the joint pipe. This suppresses, for example, changes in the inner diameter of the joint pipe section 33 connected upstream of the deformation suppression section 34. For example, the formation of a step between the inner surface of the junction pipe section 22 of the inserted downstream pipe 20 and the inner surface 33i of the joint pipe section 33 is suppressed.

[0065] Furthermore, when the fitting pipe 30 and the downstream pipe 20 are connected, the deformation suppression portion 34 and the connecting tube portion 32a suppress the formation of a step between the fitting pipe 30 and the downstream pipe 20, in which the flow path narrows downstream. In this way, the deformation suppression portion 34 can suppress a change in the diameter of the fitting pipe 30 while suppressing a step at the connection between the fitting pipe 30 and the downstream pipe 20. That is, the deformation suppression portion 34 can, for example, prevent a step from occurring or reduce the step. This can further improve transportability. For example, a decrease in the flow rate of water flowing through the drain pipe fitting 100 due to a step is suppressed.

[0066] 6, the inner diameter of the second connecting pipe section 32 is larger than the inner diameter d33 of the joint pipe section 33. That is, the inner diameter d34 of the deformation suppression section 34 is larger than the inner diameter d33 of the joint pipe section 33 and is larger than the inner diameter d32a of the connecting tubular section 32a. Because the inner diameter d34 of the deformation suppression section 34 is larger than the inner diameter d33 of the joint pipe section 33, when the junction pipe section 22 is inserted into the deformation suppression section 34, the formation of a step between the inner surface of the junction pipe section 22 and the inner surface 33i of the joint pipe section 33 is suppressed.

[0067] The inner diameter d32a of the connecting tubular portion 32a is larger than the inner diameter d33 of the joint pipe portion 33. This prevents a step from being formed between the inner surface of the junction pipe portion 22 and the inner surface 33i of the joint pipe portion 33 when the junction pipe portion 22 is inserted into the connecting tubular portion 32a.

[0068] The length L34 of the first extending portion 34a extending outward from the outer surface 33e of the joint pipe portion 33 is, for example, 10 mm or more and 30 mm or less. The axial length T34 of the deformation suppression portion 34 is, for example, 20 mm or more and 40 mm or less. Note that the deformation suppression portion 34 is not necessarily limited to a folded shape, and deformation of the joint pipe 30 may be suppressed, for example, by increasing the wall thickness of the joint pipe 30.

[0069] 7(a) and 7(b) are schematic cross-sectional views illustrating steps and protrusions provided on a pipe. As described above, the inner and outer surfaces of the joint pipe portion 33 are smooth. The term "smooth surface" refers not only to a surface that is strictly free of protrusions or steps, but also to a substantially smooth surface (i.e., a surface on which minute protrusions or steps are formed). Figures 7(a) and 7(b) illustrate examples of minute protrusions and steps that may be provided on the joint pipe portion 33. FIG. 7(a) shows a cross section of a pipe provided with a protrusion P, and FIG. 7(b) shows a cross section of a pipe provided with a step S. These cross sections are planes that pass through the central axis Ax of the pipe and are along the central axis Ax. The protrusion P and the step S rise in direction D1 (radial direction) from the non-step surface E of the pipe. The non-step surface E is the surface of the part of the pipe that does not have the protrusion P or the step S. For example, the non-step surface E is along the direction in which the central axis Ax extends. For example, the non-step surface E is a flat surface. Furthermore, in the case of a bellows-shaped pipe, the non-step surface E corresponds to the recesses including the valley bottoms of the unevenness.

[0070] The protrusions P and steps S have side surfaces F. The side surfaces F are surfaces that form the protrusions P and steps S. The side surfaces F are continuous with the non-step surfaces E and rise from the non-step surfaces E. In the cross sections of Figures 7(a) and 7(b), the side surfaces F are surfaces that are inclined at an inclination angle θF from the direction along which the non-step surfaces E are aligned (e.g., the direction of the central axis). The inclination angle θF is, for example, 40° or more and 90° or less. In other words, the step or protrusion is formed, for example, by a surface that is inclined at an angle of 40° or more from the direction of the central axis of the pipe in the non-step surface E portion. The height of the step S or protrusion P may be, for example, the length H of the side surface F along the radial direction of the non-step surface E.

[0071] For example, the side surface F may extend along the circumferential direction of the tube so as to surround the central axis Ax. The side surface F may be flat or curved. For example, in the case of a bellows-shaped tube, such convex portions are repeatedly arranged along the central axis, but on a smooth surface, convex portions like those of a bellows shape are not provided.

[0072] The smooth surface of the joint pipe portion 33 according to the embodiment only needs to be substantially smooth, and may have the above-described convex portions P and steps S formed thereon, but in such cases, the convex portions P and steps S are very small. On a substantially smooth surface, the height of the convex portions P and steps S is, for example, 6 mm or less, preferably 4 mm or less, and more preferably 1.5 mm or less. However, the smooth surface of the joint pipe portion 33 according to the embodiment does not necessarily need to have the convex portions P or steps S formed thereon.

[0073] Furthermore, the inner surface of the drain pipe joint according to the embodiment may be provided with a step whose diameter increases toward the downstream side. The inner surface of the drain pipe joint may be provided with a step or a convex portion in a portion where the drainage from the toilet bowl 220 does not flow (a portion that does not come into contact with the drainage).

[0074] FIG. 8 is a cross-sectional view illustrating the downstream pipe of the drainage pipe joint according to the embodiment. The central axis 22x of the junction pipe section 22 is, for example, linear. The central axis 22x of the junction pipe section 22 is inclined with respect to the central axis 21x of the lateral pipe section 21. The inclination angle θ22 (junction angle) of the central axis 22x with respect to the central axis 21x is equal to or greater than 30° and less than 90°, for example, equal to or greater than 45° and less than 75° (for example, 60°). When the central axis 22x is perpendicular to the central axis 21x, water flowing from the junction pipe section 22 into the lateral pipe section 21 hits the inner surface of the lateral pipe section 21, reducing the flow rate of the water. On the other hand, when the inclination angle θ22 is less than 30°, the flow rate within the lateral pipe section 21 may become too high. If the flow rate is too high, for example, the water may overtake the waste and flow, reducing the efficiency of flushing the waste. By adjusting the inclination angle θ22, an appropriate flow rate can be obtained, improving transportability.

[0075] As shown in FIG. 8, the junction pipe section 22 has a junction tube section 23 and a tip section 24. The junction tube section 23 is a downstream portion of the junction pipe section 22 and is connected to the horizontal drawing pipe section 21. The junction tube section 23 is cylindrical. For example, the inner diameter and the outer diameter of the junction tube section 23 are constant along the direction in which the central axis 22x extends. For example, the inner and outer surfaces of the junction tube section 23 are smooth.

[0076] The tip portion 24 is annular and includes an opening on the upstream side of the junction pipe portion 22. The tip portion 24 has a tapered portion 24a and a folded portion 24b. The inner surface of the tapered portion 24a is inclined toward the outside of the junction pipe portion 22 as it moves upstream. The angle θ24a at which the inner surface of the tapered portion 24a is inclined with respect to the direction in which the central axis 22x extends is, for example, 1° or more and 10° or less. The length L24a of the tapered portion 24a (the length along the direction in which the central axis 22x extends) is, for example, 5 mm or more and 20 mm or less.

[0077] The folded portion 24b is provided at the upstream end of the tapered portion 24a. The folded portion 24b extends from the upstream end of the tapered portion 24a toward the outside of the junction pipe portion 22. The folded portion 24b is provided so as to protrude outward from the outer surface of the tapered portion 24a. The length L24b by which the folded portion 24b protrudes from the outer surface of the tapered portion 24a is, for example, not less than 5 mm and not more than 20 mm.

[0078] FIG. 9 is a cross-sectional view illustrating the connection between the downstream pipe and the joint pipe of the drainage pipe joint according to the embodiment. Figure 9 shows, for example, the state before the drain pipe fitting 100 connects the toilet 220 and the horizontal drain pipe 260, in which the central axis 30x of the flexible fitting pipe 30 is not curved. As shown in Figure 9, when the downstream pipe 20 and the fitting pipe 30 are connected, the direction of the central axis 22x of the junction pipe section 22 is aligned with the direction of the central axis 30x of the fitting pipe 30. For example, the central axis 22x may coincide with the central axis 30x.

[0079] For example, in a cross section such as that shown in Figure 9 (a cross section passing through the central axis 30x and parallel to the central axis 30x), the inner and outer surfaces of the joint pipe portion 33 may not be curved but may extend parallel to the central axis 30x. For example, in the state shown in Figure 9, the inner and outer surfaces of the joint pipe portion 33 do not need to bend.

[0080] The confluence cylindrical portion 23 and tapered portion 24a of the downstream pipe 20 are inserted into the connecting cylindrical portion 32a of the joint pipe 30. The folded portion 24b of the downstream pipe 20 is inserted into the deformation suppression portion 34 of the joint pipe 30.

[0081] The folded portion 24b engages with the deformation suppression portion 34. The folded portion 24b is located between the first extending portion 34a and the second extending portion 34b of the deformation suppression portion 34. For example, the folded portion 24b abuts against at least one of the first extending portion 34a, the second extending portion 34b, and the connecting portion 34c. While connecting the junction pipe portion 22 of the downstream pipe 20 to the deformation suppression portion 34, a change in the inner diameter d33 of the joint pipe portion 33 can be suppressed.

[0082] For example, the inner diameter d23 of the confluence cylindrical portion 23 may be the same as or larger than the inner diameter d33 of the joint pipe portion 33. This can prevent a step from being formed between the inner surface 23i of the confluence cylindrical portion 23 and the inner surface 33i of the joint pipe portion 33, in which the flow path narrows downstream. The difference between the inner diameter d33 and the inner diameter d23 is, for example, 0 mm or more and 6 mm or less.

[0083] Furthermore, as described above, in this example, the tapered portion 24a is provided at the tip portion 24 of the confluence pipe portion 22. This makes it possible to prevent, for example, the formation of a step between the inner surface 33i of the joint pipe portion 33 and the inner surface of the tip portion 24, which would narrow the flow path downstream.

[0084] FIG. 10 is a cross-sectional view illustrating an upstream pipe of a drainage pipe joint according to an embodiment. The central axis 12x of the second pipe portion 12 is, for example, linear. The central axis 12x of the second pipe portion 12 is inclined with respect to the central axis 11x of the first pipe portion 11. The inclination angle θ12 of the central axis 12x with respect to the central axis 11x is, for example, not less than 30° and not more than 45°.

[0085] In this example, the upstream end 11a of the first pipe section 11 has a shape that widens toward the outside of the first pipe section 11. The inner and outer surfaces of a portion 11b of the first pipe section 11 that is downstream of the upstream end 11a may be constant along the direction in which the central axis 11x extends. The inner and outer surfaces of the downstream portion 11b are, for example, smooth.

[0086] The second pipe portion 12 has a tubular portion 15 and a downstream end portion 14. The tubular portion 15 is an upstream portion of the second pipe portion 12 and connects to the intermediate pipe portion 13. The tubular portion 15 is cylindrical. For example, the inner diameter and the outer diameter of the tubular portion 15 are constant along the direction in which the central axis 12x extends. For example, the inner and outer surfaces of the tubular portion 15 are smooth.

[0087] The downstream end portion 14 is annular and includes the downstream opening of the second pipe portion 12. The downstream end portion 14 has a tapered portion 14a and a folded portion 14b. The inner surface of the tapered portion 14a is inclined toward the outside of the second pipe portion 12 as it moves downstream. The angle θ14a at which the inner surface of the tapered portion 14a is inclined with respect to the direction in which the central axis 12x extends is, for example, 5° or more and 20° or less. The length L14a of the tapered portion 14a (the length along the direction in which the central axis 12x extends) is, for example, 10 mm or more and 25 mm or less.

[0088] The folded portion 14b is provided at the downstream end of the tapered portion 14a. The folded portion 14b extends from the downstream end of the tapered portion 14a toward the outside of the second pipe portion 12. The folded portion 14b is provided so as to protrude outward from the outer surface of the tapered portion 14a. The length L14b by which the folded portion 14b protrudes from the outer surface of the tapered portion 14a is, for example, not less than 2 mm and not more than 5 mm.

[0089] FIG. 11 is a cross-sectional view illustrating the connection between an upstream pipe and a joint pipe of a drainage pipe joint according to an embodiment. Figure 11 shows, for example, the state before the drain pipe fitting 100 connects the toilet 220 and the horizontal drain pipe 260, and the central axis 30x of the flexible fitting pipe 30 is not curved. For example, as shown in Figure 11, when the upstream pipe 10 and the fitting pipe 30 are connected, the direction of the central axis 30x of the fitting pipe 30 is aligned with the direction of the central axis 12x of the second pipe section 12. For example, the central axis 30x may coincide with the central axis 12x.

[0090] The cylindrical portion 15 (and / or tapered portion 14a) of the upstream pipe 10 is inserted into the inside of the first connecting pipe portion 31 of the joint pipe 30. In the example of Fig. 11, the folded portion 14b (and / or tapered portion 14a) of the upstream pipe 10 is inserted into the inside of the joint pipe portion 33 of the joint pipe 30. The folded portion 14b may be in contact with the inner surface 33i of the joint pipe portion 33, for example.

[0091] By providing tapered portion 14a, when second pipe portion 12 of upstream pipe 10 is inserted into joint pipe 30, it is possible to reduce the step formed between the inner surface of second pipe portion 12 of the upstream pipe and the inner surface of joint pipe 30. By providing folded portion 14b, it is possible to improve the strength of downstream end portion 14 of upstream pipe 10.

[0092] 12(a) and 12(b) are schematic views illustrating adjustment of the position of the drain pipe joint according to the embodiment. 12(a) and 12(b) differ in the relative height of the upstream pipe 10 and the downstream pipe 20. In the example of FIG. 12(b), the upstream pipe 10 (first pipe section 11) is positioned higher relative to the downstream pipe 20 (horizontal pipe section 21) compared to the example of FIG. 12(a). In other words, the relative height of the toilet bowl 220 (see FIG. 1 or 3) and the horizontal drain pipe 260 (see FIG. 1 or 2) to which the drain pipe fitting 100 is connected differs between FIG. 12(a) and FIG. 12(b).

[0093] As indicated by the arrow Ar in Figures 12(a) and 12(b), the downstream pipe 20 is rotated relative to the horizontal drainage pipe 260 (see Figure 1 or 2). That is, for example, the horizontal pulling pipe section 21 connected to the horizontal drainage pipe 260 is rotated around the central axis 21x of the horizontal pulling pipe section 21 as the rotation axis. The junction pipe section 22 is rotated around the central axis 21x of the horizontal pulling pipe section 21. In this way, the height (position in the vertical direction) and orientation of the junction pipe section 22 change.

[0094] Furthermore, the height of the drain pipe joint 100 is adjusted by rotating the upstream pipe 10 relative to the toilet bowl 220. 13(a) to 13(e) are schematic views illustrating rotation of the upstream pipe of the drainage pipe joint according to the embodiment. 13(a) to 13(e) show different rotation angles of the upstream pipe 10 relative to the toilet bowl 220. Figures 13(a) to 13(e) show how the upstream pipe 10 is rotated so that the rotation angle relative to the toilet bowl 220 gradually increases.

[0095] That is, for example, the first pipe 11 connected to the toilet bowl 220 is rotated around the central axis 11x of the first pipe 11. The second pipe 12 is rotated around the central axis 11x of the first pipe 11. In this way, the height (position in the up-down direction) and orientation of the second pipe 12 change.

[0096] For example, by rotating both the downstream pipe 20 and the upstream pipe 10, the height of the junction pipe section 22 of the downstream pipe 20 and the height of the second pipe section 12 of the upstream pipe 10 are adjusted, and the junction pipe section 22 and the second pipe section 12 are connected by the joint pipe 30. For example, by combining the rotation of the downstream pipe 20, the rotation of the upstream pipe 10, and the bending of the joint pipe 30, the height can be more easily adjusted.

[0097] In this way, when connecting the upstream pipe 10 and the downstream pipe 20 with the flexible joint pipe 30, the height of the drain pipe joint 100 can be adjusted by rotating the upstream pipe 10 and the downstream pipe 20. For example, the height of the connection position between the upstream pipe 10 and the downstream pipe 20 (the position in the vertical direction of the joint pipe 30) can be adjusted. Also, for example, the vertical length of the drain pipe joint 100 can be adjusted. According to the embodiment, it is possible to make it easier to adjust the height of the drain pipe joint 100 while suppressing a decrease in transportability.

[0098] 14(a) and 14(b) are cross-sectional views illustrating adjustment of the position of the drain pipe joint according to the embodiment. The depth (length in the front-to-rear direction) of the drain pipe joint 100 differs between Figure 14(a) and Figure 14(b). In the example of Figure 14(b), the length of the drain pipe joint 100 in the front-to-rear direction is longer than in the example of Figure 14(a). For example, Figure 14(a) shows a case where the second pipe section 12 of the upstream pipe 10 is inserted furthest to the rear into the joint pipe 30. For example, Figure 14(b) shows a case where the second pipe section 12 of the upstream pipe 10 is pulled furthest forward from the joint pipe 30.

[0099] 14(a), the tapered portion 14a of the second pipe section 12 is inserted up to the inside of the junction pipe section 22 of the downstream pipe 20. That is, the tapered portion 14a overlaps with the junction pipe section 22 and the second connecting pipe section 32 in the radial direction of the second pipe section 12. The tapered portion 14a does not have to overlap with the joint pipe section 33 in the radial direction of the second pipe section 12.

[0100] 14(b), the tapered portion 14a of the second pipe section 12 is inserted into the first connecting pipe section 31 of the joint pipe 30. That is, the tapered portion 14a overlaps with the first connecting pipe section 31 in the radial direction of the second pipe section 12. The folded-back portion 14b of the second pipe section 12 is inserted into the inside of the joint pipe section 33. For example, the folded-back portion 14b engages with the downstream end of a protrusion 31p provided on the inner surface of the first connecting pipe section 31.

[0101] In this way, the depth is adjusted by the length by which the upstream pipe 10 is inserted into the joint pipe 30. According to the embodiment, the depth of the drain pipe joint 100 can be more easily adjusted while suppressing a decrease in transportability.

[0102] Embodiments may include the following features. (Configuration 1) A drain pipe joint that connects a toilet bowl on the upstream side and a horizontal drain pipe on the downstream side, A downstream pipe connected to the horizontal drainage pipe; an upstream pipe connected to the toilet bowl side; a joint pipe connecting the downstream pipe and the upstream pipe; Equipped with The coupling pipe is a first connecting pipe portion connected to the upstream pipe; a second connecting pipe portion connected to the downstream pipe; a joint pipe portion between the first connecting pipe portion and the second connecting pipe portion, the joint pipe portion having a smooth inner surface and a constant inner diameter; A drainage pipe joint comprising: (Configuration 2) The coupling pipe is It has flexibility, A drainage pipe joint according to configuration 1, characterized in that it has a deformation suppression portion that suppresses changes in the diameter of the joint pipe portion. (Configuration 3) The deformation suppression portion is provided in the second connecting pipe portion, A drain pipe fitting as described in configuration 2, characterized in that when the fitting pipe and the downstream pipe are connected, a step is prevented from being formed between the fitting pipe and the downstream pipe, causing the flow path to narrow downstream. (Configuration 4) The deformation suppression portion is a first extension portion extending from a downstream end of the joint pipe portion toward an outside of the joint pipe; a connection portion extending downstream from an outer end of the first extension portion; a second extension portion extending from the downstream end of the connection portion toward the inside of the joint pipe; and the second connecting pipe portion has a connecting tubular portion extending downstream from an inner end of the second extending portion, 4. The drainage pipe joint according to configuration 2 or 3, wherein the inner diameter of the connecting tube portion is larger than the inner diameter of the joint pipe portion. (Configuration 5) A drainage pipe joint according to any one of configurations 1 to 4, characterized in that the upstream pipe has a downstream end portion having a tapered portion whose inner surface slopes outward from the upstream pipe as it approaches the downstream side. (Configuration 6) A drain pipe joint as described in configuration 5, characterized in that a folded portion extending toward the outside of the upstream pipe is provided at the downstream end of the tapered portion.

[0103] The above describes the embodiments of the present invention. However, the present invention is not limited to these descriptions. Design modifications made by a person skilled in the art to the above-described embodiments are also included within the scope of the present invention as long as they retain the characteristics of the present invention. For example, the shape, dimensions, materials, arrangement, installation form, etc. of each element are not limited to those exemplified and can be modified as appropriate. Furthermore, the elements of each of the above-described embodiments can be combined to the extent technically possible, and such combinations are also included within the scope of the present invention as long as they include the features of the present invention. [Explanation of symbols]

[0104] 10:Upstream pipe 11: First pipe section 11a: Upstream end 11b: Part 11x: Central axis 12: Second pipe section 12x: Central axis 13: Intermediate tube 14: Downstream end 14a: Tapered section 14b: Folded part 15:Cylinder part 17: Flange 20: Downstream pipe 21: Horizontal pipe section 21x: Central axis 22: Merging pipe section 22x: central axis 23: Merging tube part 23i:Inside 24:Tip 24a: Tapered section 24b: Folded section 30: Joint pipe 30e:edge 30f: Edge 30x: center axis 31: First connecting pipe section 31i:Inside 31p: Convex 32: Second connecting pipe section 32a: connecting tube 32i:Inside 33: Joint pipe section 33e: External surface 33i:Inside 34: Deformation suppression section 34a: 1st extension part 34b: Second extension part 34c: Connection 41, 42: Band fixing device 100: Drainage pipe fittings 210: Toilet unit 220: Toilet 225: Pipe section 250: Lining 251: Panel 252: Upper board 260: Horizontal drainage pipe 270:Support 271: Curtain board 272: Cleaning pipe 273: Tank 274: Columnar part 310: Wall 320:Floor Ax: Central axis D1: Direction D33: Outer diameter E: Non-step surface F: Side L1, L2: distance L14a, L14b, L24a, L24b, L3, L34: Length P: Convex part S: Step T34:Length d23, d32a, d33, d34: inner diameter θ12, θ22: Inclination angle θ14a, θ24a: Angle θF: Inclination angle

Claims

1. A drain pipe joint that connects a toilet bowl on the upstream side and a horizontal drain pipe on the downstream side, A downstream pipe connected to the horizontal drainage pipe; an upstream pipe connected to the toilet bowl side; a joint pipe connecting the downstream pipe and the upstream pipe; Equipped with The coupling pipe is a first connecting pipe portion connected to the upstream pipe; a second connecting pipe portion connected to the downstream pipe; a joint pipe portion between the first connecting pipe portion and the second connecting pipe portion, the joint pipe portion having a smooth inner surface and a constant inner diameter; A drainage pipe joint comprising:

2. The coupling pipe is It has flexibility, 2. A drainage pipe joint according to claim 1, further comprising a deformation suppression portion that suppresses a change in the diameter of the joint pipe portion.

3. The deformation suppression portion is provided in the second connecting pipe portion, A drain pipe fitting as described in claim 2, characterized in that when the fitting pipe and the downstream pipe are connected, a step is prevented from being formed between the fitting pipe and the downstream pipe, causing the flow path to narrow downstream.

4. The deformation suppression portion is a first extension portion extending from a downstream end of the joint pipe portion toward an outside of the joint pipe; a connection portion extending downstream from an outer end of the first extension portion; a second extension portion extending from a downstream end of the connection portion toward the inside of the joint pipe; and the second connecting pipe portion has a connecting tubular portion extending downstream from an inner end of the second extending portion, 4. The drainage pipe joint according to claim 2, wherein the inner diameter of the connecting tube portion is larger than the inner diameter of the joint pipe portion.

5. A drain pipe fitting as described in any one of claims 1 to 3, characterized in that the upstream pipe has a downstream end portion having a tapered portion whose inner surface slopes outward from the upstream pipe as it approaches the downstream side.

6. 6. A drainage pipe joint according to claim 5, wherein a folded portion extending toward the outside of the upstream pipe is provided at the downstream end of the tapered portion.

Images