Drainage components, rainwater drainage systems, construction methods for rainwater drainage systems, and buildings

Abstract

The present invention provides drainage components, a rainwater drainage system, a method for constructing a rainwater drainage system, and a building that can properly drain rainwater. [Solution] The drainage member 4 is connected to a rainwater drainage pipe 3 in which a second pipe 7 is arranged inside a first pipe 6. The drainage member 4 comprises an annular portion 41 connected to the first pipe 6 and a rib 42 formed on the inner surface of the annular portion 41. The rib 42 has a connecting portion 45 connected to the inside of the second pipe 7.

Description

Technical Field

[0001] The present invention relates to a drainage member, a rainwater drainage system, a construction method of a rainwater drainage system, and a building.

Background Art

[0002] For example, as a rainwater drain pipe, in order to drain rainwater that has fallen on a flat part of a building such as a pitched roof, a roof drain is provided on the roof of the building and drained. At this time, when经年劣化 (aging deterioration), damage, etc. occur in the rainwater drain pipe used, the rainwater drain pipe may be repaired or renovated. When repairing or renovating a rainwater drain pipe, for example, a method of disposing a renewal pipe (for example, a bellows pipe) inside the rainwater drain pipe (that is, an existing pipe) to renew the existing pipe is known (for example, see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the renewal pipe is a pipe having a smaller flow path cross-sectional area than the existing pipe. Therefore, by renewing the existing pipe with the renewal pipe, the drainage capacity of the rainwater drain pipe may decrease. In particular, when the rainfall is large due to heavy rain disasters or the like, there is a possibility that rainwater may not flow down properly.

[0005] The present invention has been made in view of the above circumstances, and an object thereof is to provide a drainage member, a rainwater drainage system, a construction method of a rainwater drainage system, and a building that can allow rainwater to flow down properly.

Means for Solving the Problems

[0006] A drainage member according to one aspect of the present invention is a drainage member connected to a rainwater drainage pipe in which a second pipe is arranged inside a first pipe, and comprises an annular portion connected to the first pipe and a rib formed on the inner surface of the annular portion, wherein the rib has a connecting portion connected to the inside of the second pipe. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a drainage member capable of properly draining rainwater, a rainwater drainage system, a method for constructing a rainwater drainage system, and a building. [Brief explanation of the drawing]

[0008] [Figure 1] This is a cross-sectional view showing a building equipped with a rainwater drainage system according to the first embodiment of the present invention. [Figure 2] This is an enlarged cross-sectional view of part II of the rainwater drainage system in Figure 1. [Figure 3] This is a perspective view showing the induction socket of the drainage member according to the first embodiment. [Figure 4] This is a plan view of the induction socket according to the first embodiment, as seen from the direction of the pipe axis. [Figure 5] Figure 4 is a cross-sectional view of the induced socket fractured along the VV line. [Figure 6] This is a disassembled perspective view of the overflow joint of the drainage member according to the first embodiment. [Figure 7] This is a cross-sectional view showing the discharge channel of the overflow fitting according to the first embodiment. [Figure 8] This is a cross-sectional view showing the inlet and outlet channels of the overflow fitting according to the first embodiment. [Figure 9] This is a cross-sectional view showing the state in which the first pipe in the rainwater drainage pipe according to the first embodiment is already installed. [Figure 10] This is a cross-sectional view illustrating an example in which the first pipe is cut at a predetermined position in step 1 according to the first embodiment. [Figure 11]A cross-sectional view for explaining an example of arranging on the upper vertical pipe obtained by cutting the second pipe in Step 2 according to the first embodiment. [Figure 12] A cross-sectional view for explaining an example of fitting an expansion joint onto the upper vertical pipe by continuing Step 3 according to the first embodiment. [Figure 13] A cross-sectional view for explaining an example of connecting an induction socket to the second pipe by continuing Step 3 according to the first embodiment. [Figure 14] A side view for explaining an example of connecting an overflow joint to the induction socket by continuing Step 3 according to the first embodiment. [Figure 15] A cross-sectional view for explaining an example of connecting the overflow joint to the expansion joint and the joint by continuing Step 3 according to the first embodiment. [Figure 16] A cross-section showing a rainwater drainage system according to the second embodiment of the present invention. [Figure 17] A perspective view showing a fixing portion according to the second embodiment. [Figure 18] A cross-sectional view showing a state where the second pipe is fixed by the fixing portion according to the second embodiment. [Figure 19] A cross-section showing a rainwater drainage system according to the third embodiment of the present invention. [Figure 20] A side view showing a fixing portion according to the third embodiment. [Figure 21] A side view showing a fixing portion according to a modification of the third embodiment. [Figure 22] A perspective view showing a drainage member according to the fourth embodiment of the present invention.

Embodiments for Carrying Out the Invention

[0009] Hereinafter, a drainage member, a rainwater drainage system, a construction method of the rainwater drainage system, and a building according to an embodiment of the present invention will be described while referring to the drawings.

[0010] (First Embodiment) As shown in FIG. 1, the building 200 includes, for example, a rooftop 201 and a rainwater drainage system 1. The rooftop 201 corresponds to a gabled roof, a corridor, a dance floor, a balcony, etc. The rooftop 201 has a flat portion 202 and a parapet P. The flat portion 202 is a substantially planar surface portion exposed to the outer space of the building 200. The flat portion 202 is a surface portion that may be directly or indirectly wetted by rainwater. The parapet P is a wall erected from the outer peripheral portion of the flat portion 202.

[0011] The rainwater drainage system 1 is arranged outdoors from the rooftop 201. The rainwater drainage system 1 is provided from the flat portion 202 of the rooftop 201 to a sewer pipe (not shown). The rainwater drainage system 1, for example, collects the rainwater that has fallen on the flat portion 202 of the rooftop 201 from an inlet 2 (described later), flows it into the sewer pipe, and drains it from the sewer pipe. The number of rainwater drainage systems 1 installed in the building 200 may be one or two or more. When the building 200 has, for example, two rainwater drainage systems 1, the two rainwater drainage systems 1 may be arranged near the opposing side surfaces of the building 200.

[0012] The rainwater drainage system 1 includes, for example, an inlet 2, a rainwater drain pipe 3, and a drainage member 4. The inlet 2 is provided on the flat portion 202 and the parapet P of the rooftop 201 via a plate-like body 31 described later. The inlet 2 may have a strainer. The inlet 2 opens horizontally in the parapet P. The rainwater drain pipe 3 includes a first pipe 6 and a second pipe 7. The first pipe 6 is an existing pipe. The first pipe 6 includes a horizontal pipe 11, an elbow 12, and a vertical pipe 13. The horizontal pipe 11 extends from the inlet 2 through the parapet P to the outer surface of the building 200. The vertical pipe 13 is arranged on the downstream side of the horizontal pipe 11 along the outer surface of the building 200. The elbow 12 connects the horizontal pipe 11 to the vertical pipe 13.

[0013] The vertical pipe 13 comprises an upper vertical pipe 15, an expansion joint 16, a lower vertical pipe 17, and a joint 18. The upper vertical pipe 15 and the lower vertical pipe 17 are divided vertically at predetermined positions in the direction of the pipe axis O. The expansion joint 16, the drainage member 4 (described later), and the joint 18 are connected between the upper vertical pipe 15 and the lower vertical pipe 17 in order from the upstream side.

[0014] As shown in Figure 2, the expansion joint 16 has a projection 21, an upstream portion 22, and a downstream portion 23. The projection 21 protrudes radially inward from the inner circumferential surface of the downstream portion in the direction of the pipe axis O. The upper surface 21a of the projection 21 is formed in a sloping shape that gradually decreases in diameter from the upstream side to the downstream side in the direction of the pipe axis O. The lower surface 21b of the projection 21 is formed in a plane perpendicular to the pipe axis O.

[0015] The upstream portion 22 is the upstream part of the projection 21 in the expansion joint 16. The inner diameter of the upstream portion 22 is formed to be approximately the same as the outer diameter of the downstream end 15a of the upper vertical pipe 15. The upstream portion 22 is movably (expandably) fitted into the downstream end 15a of the upper vertical pipe 15. A sealing member (not shown) is provided on the upstream portion 22. The sealing member seals the space between the upstream portion 22 and the downstream end 15a of the upper vertical pipe 15 in a liquid-tight manner. In other words, the upper vertical pipe 15 is inserted into the expansion joint 16 so as to be expandable and expandable in the direction of the pipe axis O.

[0016] The downstream portion 23 is the downstream part of the projection 21 in the expansion joint 16. The downstream portion 23 is bonded to the upper insertion port 71 of the drainage member 4, which will be described later. A specific example of connecting the downstream portion 23 to the upper insertion port 71 of the drainage member 4, which will be described later, will be explained in detail later. The upper insertion port 71 is an insertion port provided on the upstream side of the overflow joint 36 in the drainage member 4, which will be described later. In other words, the expansion joint 16 is interposed between the first pipe 6 (specifically, the upper vertical pipe 15) and the overflow joint 36.

[0017] The joint 18 has a projection 25, a downstream portion 26, and an upstream portion 27. The projection 25 protrudes radially inward from the inner circumferential surface approximately in the center in the direction of the pipe axis O. The upper surface 25a of the projection 25 is formed on a plane perpendicular to the pipe axis O. The lower surface 25b of the projection 25 is formed on a plane perpendicular to the pipe axis O.

[0018] The downstream portion 26 is the downstream part of the projection 25 in the joint 18. The inner diameter of the downstream portion 26 is formed to be approximately the same as the outer diameter of the upstream end 17a of the lower vertical pipe 17. The downstream portion 26 is fitted into the upstream end 17a of the lower vertical pipe 17 in a liquid-tight manner. The downstream portion 26 is bonded to the upstream end 17a of the lower vertical pipe 17 in a liquid-tight manner.

[0019] The upstream portion 27 is the upstream part of the projection 25 in the joint 18. The upstream portion 27 is bonded to the lower insertion port 76 of the drainage member 4, which will be described later. A specific example of connecting the upstream portion 27 to the lower insertion port 76 of the drainage member 4, which will be described later, will be explained in detail later. The lower insertion port 76 is an insertion port provided downstream of the overflow joint 36 in the drainage member 4, which will be described later. In other words, the joint 18 is interposed between the first pipe 6 (specifically, the lower vertical pipe 17) and the overflow joint 36.

[0020] As shown in Figures 1 and 2, the second pipe 7 is a pipe that rehabilitates the rainwater drainage pipe 3 by being placed inside the first pipe 6 (i.e., the existing pipe) to be repaired and refurbished. The second pipe 7 is, for example, a flexible replacement pipe (bellows pipe) formed in a bellows shape. In the illustrated example, the second pipe 7 is bellows-shaped with recesses or protrusions located on a plane perpendicular to the pipe axis that are alternately repeated in the direction of the pipe axis, but it is not limited to this, and for example, it may be bellows-shaped with recesses or protrusions that form a spiral around the pipe axis and are alternately repeated in the direction of the pipe axis. The second pipe 7 is positioned inside the first pipe 6 from the upstream side. The upstream end 7a of the second pipe 7 is supported inside the horizontal pipe 11 by a support member 8. The support member 8 is optional.

[0021] The upstream end 7a of the second pipe 7 is provided on the plate-like body 31. The second pipe 7 is provided on the plate-like body 31 at an opening (not shown) of the plate-like body 31. When the second pipe 7 is inserted into the first pipe 6 (specifically, the upper vertical pipe 15) from the upstream side, the plate-like body 31 is in close contact with the intersection of the flat section 202 and the parapet P. An inlet 2 is provided on the plate-like body 31.

[0022] In this state, the plate-like body 31 blocks the opening of the horizontal pipe 11 in the first pipe 6. The opening of the plate-like body 31 is open to the inlet 2. Therefore, the upstream end 7a of the second pipe 7 is open to the inlet 2 through the opening of the plate-like body 31. As a result, for example, rainwater that falls on the flat part 202 of the rooftop 201 is collected from the inlet 2 and flows into the interior of the second pipe 7 from the upstream end 7a of the second pipe 7.

[0023] In other words, the rainwater drain pipe 3 is refurbished by the second pipe 7, which is placed inside the first pipe 6. The rainwater drain pipe 3 can drain rainwater from the rooftop 201 through the inside of the second pipe 7.

[0024] The drain member 4 is connected to the first pipe 6 and the second pipe 7. The drain member 4 is connected between the expansion joint 16 and the joint 18 in the vertical pipe 13. In other words, the drain member 4 is connected between the upper vertical pipe 15 and the lower vertical pipe 17. The drain member 4 is positioned coaxially with respect to the pipe axis O of the first pipe 6 (vertical pipe 13). Hereinafter, the central axis of the drain member 4 may be referred to as the "pipe axis O". The drainage member 4 comprises an induction socket 35 (socket, member, projection member, flow straightening member, fin-shaped body, rib-shaped body, radial body) and an overflow joint 36. The induction socket 35 induces a siphon effect in rainwater passing through the inside of the second pipe 7, for example. The induction socket 35 comprises an annular portion 41 and ribs 42.

[0025] As shown in Figures 2 to 4, the annular portion 41 is formed in an annular shape along the inner circumferential surface of the upper insertion opening 71, which will be described later. The annular portion 41 is inserted into the upper insertion opening 71. The annular portion 41 is bonded to the inner circumferential surface of the upper insertion opening 71. Therefore, the annular portion 41 is connected to the downstream portion 23 of the expansion joint 16 via the upper insertion opening 71. In other words, the annular portion 41 is connected to the first pipe 6.

[0026] Ribs 42 are formed on the inner surface 41a of the annular portion 41. It is preferable to have multiple ribs 42. Here, the specific number of ribs 42 is preferably two or more, and more preferably three. The number of ribs 42 may be one, four, or six or more. In the first embodiment, three ribs 42 will be described as an example. By having multiple ribs 42, the rainwater straightening effect described later can be enhanced. The three ribs 42 are, for example, integrally molded with the annular portion 41. The three ribs 42 project radially toward the annular portion 41 from the pipe axis O and are arranged at equal intervals in the circumferential direction of the annular portion 41.

[0027] As shown in Figures 2, 3, and 5, the rib 42 has a base portion 44 and a connecting portion 45. The tip 44a of the base portion 44 extends to the inner surface of the annular portion 41 around the pipe axis O. The tips 44a of the three base portions 44 are integrally molded to the inner surface of the annular portion 41. Thus, the three ribs 42 are connected to the first pipe 6 (specifically, the downstream portion 23 of the expansion joint 16) via the annular portion 41, etc.

[0028] The connecting portion 45 can be connected when it is inserted into the interior of the downstream end 7b of the second pipe 7. The connecting portion 45 has a connecting body 51 and an inclined portion 52. The connecting body 51 extends upstream from the base 44 along the pipe axis O. The inclined portion 52 is inclined so as to gradually approach the pipe axis O from the base 44 to the tip 51a of the connecting body 51. That is, the inclined portion 52 is formed in an inclined shape so as to narrow the width of the connecting portion 45 from the base 44 to the tip 51a. The width of the connecting portion 45 is the width from the pipe axis O to the connecting portion 45. Hereinafter, the width of the connecting portion 45 may be referred to as the "rib width".

[0029] The inclined portion 52 has a first portion 54, a bending point 55 (bending portion), and a second portion 56. The bending point 55 is located approximately in the center of the inclined portion 52 in the direction of the pipe axis O. The first portion 54 extends from the base 44 to the bending point 55. The first portion 54 is formed at a first inclination angle (angle of inclination) θ1 with respect to the pipe axis O. The rib width of the first portion 54 is W1. The second portion 56 extends from the bending point 55 to the tip 51a. The second portion 56 is formed at a second inclination angle (angle of inclination) θ2 with respect to the pipe axis O. The rib width of the second portion 56 is W2.

[0030] The first inclination angle θ1 is smaller than the second inclination angle θ2. That is, the first section 54 is formed with a gentler inclination angle than the second section 56. Therefore, the rib width W1 of the first section 54 is larger than the rib width W2 of the second section 56. In other words, the second inclination angle θ2 is larger than the first inclination angle θ1. That is, the second section 56 is formed with a steeper inclination angle than the first section 54. Therefore, the rib width W2 of the second section 56 is smaller than the rib width W1 of the first section 54. In this way, the inclined section 52 changes the inclination angle between the first section 54 and the second section 56 at the bending point 55. Therefore, the rib width W1 of the first section 54 can be made larger than the rib width W2 of the second section 56. Also, the rib width W2 of the second section 56 can be made smaller than the rib width W1 of the first section 54.

[0031] Therefore, for example, at the connection part 45, the second portion 56 from the bend point 55 to the tip 51a can be connected (inserted) to a second tube (not shown) of a first size (e.g., size 60). In this case, the second tube of the first size is inserted along the second portion 56 from the tip 51a to just before the bend point 55. Furthermore, the first portion 54 on the base 44 side from the bending point 55 can be connected (inserted) to a second tube 7 of a second size (for example, size 75) which is larger than the first size. In this case, the second tube 7 of the second size is inserted beyond the bending point 55 towards the base 44 side.

[0032] In this embodiment, in a front view of the rib 42, the first portion 54 and the second portion 56 intersect at the bending point 55. However, instead of such a bending point 55, a rounded bend, such as a fillet, may be used. In this case, the first portion 54 and the second portion 56 intersect on imaginary lines extending outside the rib 42.

[0033] Next, an example of draining rainwater using the induction socket 35 will be explained based on Figures 1 and 3. As shown in Figure 1, rainwater that falls on the flat area 202 of the rooftop 201 is collected, for example, from the inlet 2 and flows into the second pipe 7 from the upstream end 7a of the second pipe 7. The rainwater that flows into the second pipe 7 flows down to the downstream end 7b, for example, while swirling inside the second pipe 7.

[0034] As shown in Figures 1 and 3, the three ribs 42 of the induction socket 35 are connected to the downstream portion 23 of the expansion joint 16 via the annular portion 41 and the upper insertion opening 71. Furthermore, the connection portion 45 of the three ribs 42 is connected while inserted into the interior of the downstream end 7b of the second pipe 7. Thus, rainwater that would otherwise swirl and flow from the downstream end 7b of the second pipe 7 to the three ribs 42 can be straightened by the three ribs 42.

[0035] Here, by providing three (i.e., multiple) ribs 42, the effect of straightening the flow of rainwater can be enhanced. By straightening the flow of rainwater with the three ribs 42, it becomes more difficult for air to enter the rainwater. Therefore, the induction socket 35 can induce the siphon effect. In other words, by connecting the induction socket 35 to the second pipe 7 of the rainwater drain pipe 3, the siphon effect can be induced in the rainwater passing through the inside of the second pipe 7.

[0036] As shown in Figures 2 and 6, the overflow joint 36 is provided between the upper vertical pipe 15 and the lower vertical pipe 17. The overflow joint 36 is located downstream of the three ribs 42 in the induction socket 35. Specifically, the overflow joint 36 comprises a cylindrical upper connecting portion 61 that connects to the expansion joint 16 and a cylindrical lower connecting portion 62 provided below the upper connecting portion 61 and connecting to the joint 18. The upper connecting portion 61 has a cylindrical cover portion 64. The lower connecting portion 62 has a cylindrical peripheral wall portion 65.

[0037] As shown in Figures 2, 6, and 7, the overflow joint 36 has an inlet channel 67 formed by a peripheral wall 65 and a cover 64 that guides rainwater to the outside of the normal flow pipeline H3, which is a straight line connecting the pipeline H1 of the upper vertical pipe 15 and the pipeline H2 of the lower vertical pipe 17, and a discharge channel 68 that causes the rainwater guided from the inlet channel 67 to flow downward. Here, "normal conditions" refers to the amount of rainfall when the amount of rainwater is not such that it overflows from the rainwater drain pipe 3. In addition, the inlet channel 67 and the discharge channel 68 are adjacent to each other on the same circumference (the same circle in the first embodiment).

[0038] The upper connecting portion 61 includes an upper insertion opening 71 that is inserted into the expansion joint 16, a male connecting wall portion 72, and a cover portion 64. The upper insertion opening 71 is formed with an outer diameter that is approximately the same as the inner diameter of the expansion joint 16, so that its outer wall surface is in close contact with the inner wall surface of the expansion joint 16. The upper insertion opening 71 is bonded to the expansion joint 16 in a liquid-tight manner. The tip 71a of the upper insertion opening 71 abuts against the lower surface 21b of the projection 21 on the expansion joint 16.

[0039] The male connector wall portion 72 comprises a tubular body portion 72a formed in a continuous shape from the lower end of the upper insertion opening 71, and downward-extending upper tongue pieces 72b provided at equal intervals in the annular direction at the lower end of the tubular body portion 72a. Notches 74 cut upward are formed between the upper tongue pieces 72b, 72b. The cover portion 64 is designed to prevent rainwater from splashing when rainwater flows into the discharge groove 83, which will be described later. It is tapered from the lower end of the upper insertion opening 71, and then formed cylindrically downward with a constant diameter around the pipe axis O, at a predetermined distance from the male connector wall portion 72.

[0040] The lower connection portion 62 has a peripheral wall portion 65 that receives rainwater when rainfall exceeds the drainage capacity of the sewer pipe (not shown) installed at the downstream end of the lower vertical pipe 17, and a lower insertion opening 76 that fits into the inside of the joint 18.

[0041] The circumferential wall portion 65 is formed as a whole into a cylindrical shape with irregularities in the circumferential direction centered on the pipe axis O. Specifically, the circumferential wall portion 65 is an arc shape that can be closely attached to the outer surface of the male connecting wall portion 72 (i.e., an arc shape that forms a normal water pipeline H3), and is provided alternately in the circumferential direction with a plurality of female connecting wall portions 78 provided at equal intervals in the annular direction, and a plurality of inlet wall portions 79 that form recesses that expand the space to the outside of the normal water pipeline H3 (radially outward in the first embodiment) and guide rainwater to the outside of the normal water pipeline H3. The water pipeline H3 is connected to the pipeline H1 of the upper vertical pipe 15 via an expansion joint 16 and to the pipeline H2 of the lower vertical pipe 17 via a joint 18. Under normal conditions, the water pipeline H3 allows normal rainwater to flow from pipeline H1 to pipeline H2.

[0042] The female connecting wall portion 78 has a lower tongue piece 81 that protrudes above the height of the upper end of the introduction wall portion 79. The inlet wall portion 79 bulges radially outward in a U-shape cross-section. The inlet wall portion 79 forms an inlet groove 82 that opens into the water pipeline H3. The inlet groove 82 extends in the direction of the pipe axis O. The lower end of the inlet groove 82 is closed, and the upper end is open. Furthermore, the peripheral wall portion 65, together with the introduction wall portion 79, has a discharge groove 83 formed therein. The discharge groove 83 extends in the direction of the pipe axis O. The discharge groove 83 has openings at its upper and lower ends. The introduction groove 82 and the discharge groove 83 are formed alternately in the circumferential direction on the same circumference.

[0043] The upper connecting portion 61 and the lower connecting portion 62 are connected by the male connecting wall portion 72 being inserted inside the female connecting wall portions 78, 78... In this state, the upper tongue piece 72b of the male connecting wall portion 72 is positioned to block a part of the introduction groove 82 (i.e., the upper end of the peripheral wall portion 65). As a result, the introduction channel 67 is formed by the upper tongue piece 72b and a part of the introduction groove 82. The introduction channel 67 extends in the direction of the pipe axis O. The lower end of the introduction channel 67 opens into the introduction groove 82, and the upper end opens upward. Hereinafter, the opening at the lower end may be referred to as the "lower end opening," and the opening at the upper end as the "upper end opening."

[0044] The cover portion 64 is positioned to cover the entire peripheral wall portion 65, so that the cover portion 64 contacts the introduction wall portion 79. Thus, the discharge channel 68 is formed by the discharge groove 83 and the cover portion 64. The discharge channel 68 extends in the direction of the pipe axis O. The upper end of the discharge channel 68 opens upward (i.e., the upper end opening) and the lower end opens downward. Hereinafter, the upper end opening may be referred to as the "upper end opening" and the lower end opening as the "lower end opening". The upper opening of the discharge channel 68 is positioned at approximately the same height as the upper opening of the inlet channel 67 in the direction of the pipe axis O.

[0045] As shown in Figures 2 and 7, the lower insertion opening 76 is formed with an outer diameter that is approximately the same as the inner diameter of the joint 18, so that its outer wall surface is in close contact with the inner wall surface of the joint 18. The lower insertion opening 76 is bonded to the joint 18 in a liquid-tight manner. The tip 76a of the lower insertion opening 76 abuts against the projection 25 of the joint 18 (specifically, the upper surface 25a).

[0046] Here, for example, the height of the foundation of a typical house is generally about 40 cm. Therefore, in order to drain water from inside the vertical pipe 13 when the crawl space is flooded, it is preferable to install the overflow joint 36 at a height of 40 cm or more, and it is even more preferable to install it at a height of 1 m or more from the standpoint of ease of construction and management.

[0047] Next, an example of draining rainwater using the overflow fitting 36 will be explained based on Figures 6 to 8. As shown in Figures 6 to 8, under normal conditions, rainwater flows from the upper vertical pipe 15 to the overflow joint 36. The flowing rainwater then flows to the upper inlet 71 of the upper connection part 61, the male connection wall part 72, the female connection wall part 78 of the peripheral wall part 65, and the lower inlet 76 of the lower connection part 62. The rainwater that flows to the lower inlet 76 flows through the lower inlet 76 towards the lower vertical pipe 17. The rainwater that flows into the lower vertical pipe 17 is discharged into a rainwater infiltration pit or the like buried underground through a sewer pipe (not shown) connected to the lower vertical pipe 17.

[0048] On the other hand, during heavy rainfall exceeding the drainage capacity of the sewer pipes, or when the rainwater infiltration basin is flooded, rainwater gradually accumulates inside the lower vertical pipe 17, causing the water level to rise. When the rainwater level reaches the inside of the surrounding wall 65, some of the rainwater is temporarily stored in the normal drainage pipeline H3 and inlet channel 82. If the amount of rainfall exceeding the drainage capacity of the drainage pipe does not exceed the volume of the inlet channel 82, the rainwater is gradually drained while being temporarily stored in the surrounding wall 65.

[0049] If the amount of rainfall exceeds the drainage capacity of the drainage pipe and exceeds the volume of the water pipeline H3, the rainwater will rise further in water level and reach the lower end opening of the inlet channel 67 from the inlet groove 82. The rainwater that reaches the lower end opening flows into the interior of the inlet channel 67 from the lower end opening as indicated by arrow A. The rainwater that flows into the interior of the inlet channel 67 reaches the upper opening of the inlet channel 67 and overflows from the upper opening as indicated by arrow B. Rainwater overflowing from the upper opening flows into the interior of the discharge channel 68 through the upper end opening of the discharge channel 68 as indicated by arrow C. The rainwater that flows into the interior flows down the interior of the discharge channel 68 and is drained out from the lower end opening as indicated by arrow D. In other words, the overflow joint 36 allows rainwater to be efficiently overflowed downwards when there is a large amount of rainfall within a certain period of time.

[0050] Here, as shown in Figure 2, the overflow joint 36 is positioned downstream of the three ribs 42. Therefore, for example, if rainfall increases and rainwater overflows into the water pipeline H3 of the overflow joint 36, the overflow rainwater can be directed downward by the overflow joint 36. This prevents the rainwater that overflows into the water pipeline H3 from rising upstream of the three ribs 42.

[0051] In the first embodiment, an example is described in which the induction socket 35 and the overflow joint 36 of the drainage member 4 are provided separately, but the invention is not limited to this. As another example, the induction socket 35 and the upper connecting portion 61 of the overflow joint 36 may be molded as a single unit.

[0052] Furthermore, the upper connection portion 61 of the overflow fitting 36 is exposed to the outside. For this reason, it is preferable that the color of the upper connection portion 61 matches the exterior wall of the building 200. The color of the upper connection portion 61 can be arbitrarily selected. In addition, if the induction socket 35 and the overflow fitting 36 are separate components, the induction socket 35 and the overflow fitting 36 may be molded in the same color or in different colors.

[0053] Furthermore, each component of the rainwater drainage system 1, including the drainage member 4, may be made of a resin that improves weather resistance. In this case, for example, the component may have a two-layer structure comprising an outer layer made of a resin that improves weather resistance and an inner layer made of PVC or the like.

[0054] Next, the construction process for the rainwater drainage system 1 will be explained based on Figures 9 to 15. As shown in Figure 9, a first pipe 6 is already installed in building 200. The horizontal pipe 11 of the first pipe 6 opens into the inlet 2 on the rooftop 201. The first pipe 6 has deteriorated over time, is damaged, etc. The process for repairing and renovating the first pipe 6 will be described below.

[0055] In step 1 shown in Figure 10, the vertical pipe 13 of the first pipe 6 is cut at a predetermined position. By cutting the vertical pipe 13, it is divided into an upper vertical pipe 15 on the upstream side and a lower vertical pipe 17 on the downstream side.

[0056] In step 2 shown in Figure 11, the inlet 2 is removed. With the inlet 2 removed, the second pipe 7 is inserted into the upper vertical pipe 15 from the upstream side via the horizontal pipe 11 and elbow 12. With the second pipe 7 inserted, the plate-shaped body 31 is positioned at the mounting location of the inlet 2. In this state, the inlet 2 is installed from above the plate-shaped body 31. The plate-shaped body 31 is in close contact with the intersection of the flat section 202 and the parapet P. Therefore, the opening of the horizontal pipe 11 can be blocked by the plate-like body 31. Furthermore, the upstream end 7a of the second pipe 7 can be opened to the inlet 2. In this state, the second pipe 7 is positioned inside the upper vertical pipe 15, and the downstream end 7b of the second pipe 7 protrudes downstream from the downstream end 15a of the upper vertical pipe 15.

[0057] In step 3 shown in Figure 12, the expansion joint 16 is moved upward through the downstream end 7b of the second pipe 7 as indicated by arrow E. By moving the expansion joint 16 upward, the upstream portion 22 of the expansion joint 16 is fitted into the downstream end 15a of the upper vertical pipe 15 in an expandable and contractible manner.

[0058] By continuing step 3 shown in Figure 13, with the expansion joint 16 fitted into the downstream end 15a of the upper vertical pipe 15, the expansion joint 16 is positioned upstream of the downstream end 7b of the second pipe 7 as indicated by arrow F. In this state, the connection parts 45 of the three ribs 42 of the induction socket 35 are inserted into the downstream end 7b of the second pipe 7 from the downstream side. By inserting the connection parts 45 of the three ribs 42, the three connection parts 45 are connected to the downstream end 7b of the second pipe 7.

[0059] By continuing step 3 shown in Figure 14, the upper insertion port 71 of the overflow fitting 36 is fitted into the annular portion 41 of the induction socket 35 from the downstream side as indicated by arrow G. The annular portion 41 is then connected to the fitted upper insertion port 71. Thus, the overflow fitting 36 is connected to the induction socket 35. As a result, the drainage member 4 (induction socket 35 and overflow fitting 36) is connected as a single unit.

[0060] By continuing step 3 shown in Figure 15, the drain member 4 is moved toward the expansion joint 16 side as indicated by arrow H. By moving the drain member 4, the upper opening 71 of the overflow joint 36 is inserted into the downstream part 23 of the expansion joint 16. Here, the second pipe 7 is a bellows pipe. Therefore, by contracting the second pipe 7, the movement of the drain member 4 toward the expansion joint 16 side is permitted. By inserting the upper opening 71 of the overflow joint 36 into the downstream part 23 of the expansion joint 16, the upper opening 71 is connected to the downstream part 23 of the expansion joint 16.

[0061] With the upper insertion port 71 connected to the downstream section 23, the drainage member 4 is kept positioned upstream of the predetermined mounting position. In this state, the downstream section 26 of the joint 18 is fitted into the upstream end 17a of the lower vertical pipe 17, and the downstream section 26 of the joint 18 is connected to the upstream end 17a.

[0062] With the downstream end 26 of the joint 18 connected to the upstream end 17a, the drain member 4 is moved downstream towards the joint 18 as indicated by arrow I. The lower insertion port 76 of the overflow joint 36 is inserted into the upstream end 27 of the joint 18, connecting the lower insertion port 76 to the upstream end 27 (see Figure 2). In other words, in step 3 shown in Figures 12 to 15, the drainage member 4 (i.e., the induction socket 35 and the overflow fitting 36) is connected to the first pipe 6 and the second pipe 7. This completes steps 1 through 3 of the construction method for rainwater drainage system 1.

[0063] As described above, according to the drainage member 4 of the first embodiment, the connection portion 45 of the three ribs 42 is connected to the downstream end 7b of the second pipe 7, as shown in Figures 2 and 3. Therefore, rainwater that is trying to flow in a swirling manner from the second pipe 7 can be straightened by the three ribs 42. By straightening the flow of rainwater, it is made more difficult for air to enter the rainwater, and the siphon effect can be induced. Therefore, rainwater can be properly drained by the siphon effect.

[0064] Here, if the downstream end 7b of the second pipe 7 is not fixed inside the first pipe 6, for example, when rainfall increases, the downstream end 7b of the second pipe 7 will move inside the first pipe 6 (specifically, the upper vertical pipe 15). As a result, it becomes difficult for the second pipe 7 to properly drain rainwater. In addition, the downstream end 7b of the second pipe 7 may come into contact with the inner surface of the upper vertical pipe 15, potentially damaging the inner surface. Therefore, the annular section 41 was connected to the upper vertical pipe 15, and the three connecting sections 45 were connected to the inside of the second pipe 7. Thus, the downstream end 7b of the second pipe 7 can be fixed (held) to the upper vertical pipe 15 via the connecting sections 45 of the three ribs 42 and the annular section 41. This allows rainwater to be properly drained by the second pipe 7. In addition, it is possible to prevent the downstream end 7b of the second pipe 7 from coming into contact with the inner surface of the upper vertical pipe 15.

[0065] Furthermore, the three connection sections 45 have inclined sections 52, and the rib width of the connection section 45 is narrowed towards the tip 51a. Therefore, for example, multiple types of second pipes 7 of different sizes can be connected to the three connection sections 45, eliminating the need to prepare drainage members 4 to match multiple types of second pipes 7 of different sizes, thus simplifying construction.

[0066] Furthermore, as shown in Figures 2 and 5, in the inclined section 52, the first inclination angle θ1 of the first part 54 and the second inclination angle θ2 of the second part 56 are changed at the bending point 55. Therefore, for example, the second part 56 can be connected to a second pipe (not shown) of a first size. In this case, the second pipe of the first size is inserted from the tip 51a to just before the bending point 55. Also, the first part 54 can be inserted into a second pipe 7 of a second size which is larger than the first size. In this case, the second pipe 7 of the second size is inserted beyond the bending point 55 towards the base 44. This allows for easy positioning of the joint 55 by visually inspecting it, enabling the insertion of the joint 45 into the second pipe 7 to be completed, thus facilitating construction.

[0067] Furthermore, as shown in Figures 6 to 8, for example, if the amount of rainfall increases and rainwater overflows into the water pipeline H3 of the overflow joint 36, the rainwater overflowing into the water pipeline H3 can be guided to the outside of the water pipeline H3 by the intake channel 67. Furthermore, the rainwater guided to the outside of the water pipeline H3 by the intake channel 67 can be discharged downwards by the discharge channel 68. This prevents the rainwater overflowing into the water pipeline H3 of the overflow joint 36 from overflowing to the upstream side of the second pipe 7 (for example, the rooftop 201 of the building 200).

[0068] Furthermore, as shown in Figure 2, an expansion joint 16 is interposed between the upper vertical pipe 15 and the overflow joint 36 in the first pipe 6. This allows the expansion joint 16 to absorb, for example, the thermal expansion of the upper vertical pipe 15 and the thermal expansion of the overflow joint 36.

[0069] Furthermore, as shown in Figures 2 and 7, the overflow joint 36 is positioned downstream of the three ribs 42. Therefore, for example, if rainfall increases and rainwater overflows into the drainage pipe H3, the overflow rainwater can be directed downward by the overflow joint 36. This prevents the overflow rainwater from rising upstream of the three ribs 42. Thus, the siphon effect induced by the three ribs 42 can be continued, allowing for proper drainage of rainwater.

[0070] According to the rainwater drainage system 1 of the first embodiment described above, as shown in Figure 1, a drainage member 4 is connected to the rainwater drainage pipe 3. This allows rainwater to be properly drained by the siphon effect through the drainage member 4 (specifically, the induction socket 35).

[0071] According to the building 200 of the first embodiment described above, the building 200 is equipped with a rainwater drainage system 1, and the rainwater drainage system 1 is used to drain rainwater from the rooftop 201. This allows the rainwater to be properly drained by the siphon effect.

[0072] According to the construction method of the rainwater drainage system 1 according to the first embodiment described above, as shown in Figures 9 to 15, the first pipe 6 is cut and the second pipe 7 is placed inside from the upstream side. With the second pipe 7 placed inside the first pipe 6, the drainage member 4 is connected to the first pipe 6 and the second pipe 7. This completes the construction method of the rainwater drainage system 1. In this way, the rainwater drainage system 1 can be easily constructed according to the construction method of the rainwater drainage system 1. Furthermore, by constructing the rainwater drainage system 1 using the construction method described above, rainwater can be properly drained by the siphon effect.

[0073] Next, the second to fourth embodiments will be described with reference to Figures 16 to 22. In the second to fourth embodiments, components that are the same as or similar to those in the first embodiment are denoted by the same reference numerals, and detailed explanations are omitted.

[0074] (Second Embodiment) As shown in Figures 16 to 18, the rainwater drainage system 100 replaces the drainage member 4 of the first embodiment with a drainage member 102. The drainage member 102 comprises the drainage member 4 of the first embodiment and a fixing part 105. The other components of the rainwater drainage system 100 are the same as those of the rainwater drainage system 1 of the first embodiment. The rainwater drainage system 100 is located outdoors from the rooftop 201, similar to the rainwater drainage system 1 of the first embodiment.

[0075] The fixing part 105 comprises a fixing part body 106 and a fastening member 107. The fixing part body 106 has a first annular part 112 and a second annular part 113. The first annular part 112 is formed in an annular shape. The first annular part 112 is tightly fitted between the inner circumferential surface of the downstream part 23 of the expansion joint 16 and the outer circumferential surface of the annular part 41 (see Figure 2). The first annular part 112 is bonded to the expansion joint 16 and the annular part 41 in a liquid-tight manner.

[0076] The second annular portion 113 is integrally formed with the first annular portion 112 via an annular stepped portion 114. Specifically, the downstream end of the second annular portion 113 is integrally formed with the upstream end of the first annular portion 112 via an annular stepped portion 114. The second annular portion 113 has a smaller diameter than the first annular portion 112. The second annular portion 113 maintains a small radial distance from the downstream end 7b of the second pipe 7. The second annular portion 113 has a pair of grooves 116 and a pair of openings 117.

[0077] The pair of grooves 116 and the pair of openings 117 are arranged alternately and continuously in the same arc shape in the circumferential direction of the second annular portion 113. Specifically, the pair of grooves 116 extend in a curved shape in the circumferential direction on the outer surface of the second annular portion 113, in the portion facing the radial direction. The pair of grooves 116 are grooves that are recessed radially inward relative to the outer surface of the second annular portion 113. The pair of grooves 116 are located approximately in the center in the direction of the pipe axis O.

[0078] The pair of openings 117 are located on the outer circumferential surface of the second annular portion 113, avoiding the pair of grooves 116. The areas avoiding the pair of grooves 116 are radially opposed areas on the outer circumferential surface of the second annular portion 113. The pair of openings 117 extend radially from the outer circumferential surface to the inner circumferential surface of the second annular portion 113. One opening 117 is continuous with one end of the pair of grooves 116. The other opening 117 is continuous with the other end of the pair of grooves 116.

[0079] The fastening member 107 is, for example, a hose clamp. A hose clamp is a commonly used fastening member, and hereafter, the fastening member 107 will be described as "hose clamp 107". However, the fastening member 107 is not limited to a hose clamp. Other members may be used as the fastening member 107. The hose clamp 107 is positioned in the pair of grooves 116 and the pair of openings 117 in the second annular portion 113, for example, when the tightening screw 108 is loosened to make the diameter of the clamp body 109 larger than the diameter of the second annular portion 113.

[0080] The hose clamp 107, positioned in a pair of grooves 116 and a pair of openings 117, is fixed to the pair of grooves 116 by tightening the tightening screws 108. Once fixed, the band body 109 is positioned linearly by continuing to tighten the tightening screws 108, so that the pair of parts 109a corresponding to the pair of openings 117 are aligned. The pair of linearly arranged portions 109a press the downstream end 7b of the second pipe 7 radially inward through the pair of openings 117. As a result, the fixing part 105 can fix the pair of parts 109a of the hose band 107 to the outer surface (outer circumference) of the downstream end 7b of the second pipe 7.

[0081] According to the rainwater drainage system 100 of the second embodiment described above, by fixing the fixing part 105 to the outer surface of the downstream end 7b of the second pipe 7, the downstream end 7b can be tightened with the fixing part 105. Therefore, the downstream end 7b can be properly crushed with the fixing part 105. This allows rainwater to be sealed inside the second pipe 7. In other words, it makes it difficult for air to enter the rainwater and induces a siphon effect. Therefore, rainwater can be properly drained by the siphon effect.

[0082] Furthermore, the drainage member, rainwater drainage system 100, construction method of the rainwater drainage system, and building according to the second embodiment can achieve the same functions and effects as the rainwater drainage system 1 of the first embodiment.

[0083] (Third embodiment) As shown in Figures 19 and 20, the rainwater drainage system 140 is modified in which the drainage member 102 of the second embodiment is replaced with a drainage member 142. The drainage member 142 is modified in which the fixing part 105 of the second embodiment is replaced with a fixing part 145. The other components of the rainwater drainage system 140 are the same as those of the rainwater drainage system 100 of the second embodiment. The rainwater drainage system 140 is located outdoors from the rooftop 201, similar to the rainwater drainage system 100 of the second embodiment.

[0084] The fixing portion 145 is a replacement of the fixing portion body 106 in the second embodiment with the fixing portion body 146. That is, the fixing portion 145 comprises the fixing portion body 146 and a fastening member 107 (see Figure 18). The fixing portion body 146 replaces the pair of grooves 116 in the second embodiment with a single groove 148, and replaces the pair of openings 117 in the second embodiment with a single opening 117. The groove 148 is a replacement of the pair of grooves 116 in the second embodiment which extend in a curved shape in the circumferential direction along the outer surface of the second annular portion 113.

[0085] The band body 109 of the hose clamp 107 is fixed to the groove 148 (see Figure 18 for both). In this state, by tightening the tightening screw 108 (see Figure 18), the portion 109a (see Figure 18) corresponding to the opening 117 is positioned linearly. The linearly positioned portion 109a presses the downstream end 7b of the second pipe 7 radially inward through the opening 117. As a result, the fixing portion 145 can be fixed to the outer surface of the downstream end 7b of the second pipe 7 by portion 109a of the hose band 107.

[0086] According to the rainwater drainage system 140 of the third embodiment described above, rainwater can be properly drained by the siphon effect, similar to the rainwater drainage system 100 of the second embodiment. Furthermore, the drainage member, rainwater drainage system 140, construction method of the rainwater drainage system, and building according to the third embodiment can achieve the same functions and effects as the rainwater drainage system 1 of the first embodiment.

[0087] (modified version) As shown in Figure 21, the modified fixing part 150 replaces the fixing part 145 of the third embodiment. The fixing part 150 is a cylindrical body that can be fitted onto the downstream end 7b of the second pipe 7. Like the fixing part 145, the fixing part 150 has one opening 152 on its side.

[0088] According to the fixing part 150, when fitted onto the downstream end 7b (see Figure 19) of the second pipe 7, the band body 109 of the hose band 107 is positioned in the opening 152 (see Figure 18 for both). In this state, by tightening the tightening screw 108 (see Figure 18), the part 109a (see Figure 18) corresponding to the opening 152 is positioned linearly. The linearly positioned part 109a presses the downstream end 7b (see Figure 19) of the second pipe 7 radially inward through the opening 152.

[0089] As a result, the fixing part 150 can be fixed to the outer surface of the downstream end 7b of the second pipe 7 by portion 109a of the hose band 107. In other words, with the modified fixing part 150, rainwater can be properly drained by the siphon effect, similar to the fixing part 145 of the third embodiment.

[0090] (Fourth Embodiment) As shown in Figure 22, the rainwater drainage system 160 replaces the drainage member 4 of the first embodiment with a drainage member 162. The drainage member 162 includes an induction socket 163, an overflow joint 36, and a fixing part 164 (see Figure 2). The other components of the rainwater drainage system 160 are the same as those of the rainwater drainage system 1 of the first embodiment. The rainwater drainage system 160 is located outdoors from the rooftop 201 (see Figure 1), similar to the rainwater drainage system 1 of the first embodiment.

[0091] The induction socket 163 replaces the three ribs 42 in the first embodiment with three ribs 166. The three ribs 166 replace the inclined portion 52 in the first embodiment with an inclined portion 167. The three inclined portions 167 have a recess 168. The recess 168 is a V-shaped depression formed toward the pipe axis O (i.e., radially inward). The recess 168 causes the connection portion 45 to be reduced in diameter and constricted at an intermediate position in the direction of the pipe axis O.

[0092] The fixing part 164 is a hose clamp. The fixing part 164 is a clamp similar to the hose clamp 107 in the second embodiment. However, the fixing part 164 is not limited to a hose clamp. Other fastening members may be used as the fixing part 164. The fixing portion 164 is positioned around the downstream end 7b of the second pipe 7 with the tightening screw 171 loosened so that the diameter of the band body 172 is larger than the diameter of the downstream end 7b of the second pipe 7. The fixing portion 164 is positioned at the locations of the three recesses 168 in the direction of the pipe axis O.

[0093] The fixing portion 164 positioned at the three recesses 168 causes the band body 172 to change in diameter toward the three recesses 168 when the tightening screw 171 is tightened. The band body 172, having changed in diameter, presses the downstream end 7b of the second pipe 7 radially inward. As a result, the downstream end 7b is recessed radially inward along the three recesses 168. This allows the fixing portion 164 to be fixed to the outer surface (outer circumference) of the downstream end 7b of the second pipe 7.

[0094] According to the rainwater drainage system 160 of the fourth embodiment described above, by fixing the fixing part 164 to the outer surface of the downstream end 7b of the second pipe 7, the downstream end 7b can be tightened with the fixing part 164. Therefore, the downstream end 7b can be properly crushed with the fixing part 164. This allows rainwater to be sealed inside the second pipe 7. In other words, it makes it difficult for air to enter the rainwater and induces a siphon effect. Therefore, rainwater can be properly drained by the siphon effect.

[0095] Furthermore, the drainage member, rainwater drainage system 160, construction method of the rainwater drainage system, and building according to the fourth embodiment can achieve the same functions and effects as the rainwater drainage system 1 of the first embodiment.

[0096] It should be noted that the technical scope of the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the invention.

[0097] In the above embodiment, the expansion joint 16 and the overflow joint 36 were separate components, but a single joint may also perform the functions of both. In this case, the joint that performs both functions may be located either upstream of the induction socket 35 or downstream of the induction socket 35. The rainwater drainage systems 1,100, 140, and 160 do not need to be equipped with expansion joints 16, joints 18, or overflow joints 36. The connecting portion 45 does not necessarily have to include a bending point 55 or inclined portions 52,167.

[0098] Furthermore, it is possible to replace the components in this embodiment with well-known components as appropriate, without departing from the spirit of the present invention.

[0099] (Note) The above embodiment can be understood, for example, as follows:

[0100] <1> A drainage member according to one aspect of the present invention is a drainage member connected to a rainwater drainage pipe in which a second pipe is arranged inside a first pipe, and comprises an annular portion connected to the first pipe and a rib formed on the inner surface of the annular portion, wherein the rib has a connecting portion connected to the inside of the second pipe.

[0101] In the drainage member, the rib has a connection part that connects to the inside of the second pipe. Therefore, the rib can straighten the flow of rainwater that is trying to swirl from the second pipe to the first pipe. In other words, it makes it difficult for air to enter the rainwater and induces the siphon effect. Therefore, the rainwater can be properly drained by the siphon effect.

[0102] If the downstream end of the second pipe is not fixed inside the first pipe, then, for example, when rainfall increases, the downstream end of the second pipe will move inside the first pipe. As a result, it becomes difficult for the second pipe to properly drain rainwater. Furthermore, the downstream end of the second pipe may come into contact with the inner surface of the first pipe, potentially damaging the inner surface. Therefore, the annular section was connected to the first pipe, and the connecting section was connected to the inside of the second pipe. Thus, the downstream end of the second pipe can be fixed (held) to the first pipe via the rib connecting section and the annular section. This allows rainwater to be properly drained by the second pipe. In addition, it is possible to prevent the downstream end of the second pipe from coming into contact with the inner surface of the first pipe.

[0103] <2> the above <1> In the drainage member relating to this, the connecting portion may have an inclined portion that narrows in width towards the tip.

[0104] The drainage member has an inclined section at the connection point, and the width of the connection point narrows towards the tip. Therefore, for example, multiple types of second pipes of different sizes can be connected to the connection point. This eliminates the need to prepare drainage members to match multiple types of second pipes of different sizes, making installation easier.

[0105] <3> the above <2> In the drainage member relating to the above, the inclined portion may have a bent portion in which the angle of inclination changes with respect to the pipe axis of the drainage member.

[0106] The drainage member has a bend in the inclined section, and the angle of inclination of the inclined section is changed at the bend. Therefore, for example, at the connection section, the second section from the bend towards the tip can be connected (inserted) to a second pipe of a first size (e.g., size 60). In this case, the second pipe of the first size is inserted from the tip up to just before the bend. Also, the first section from the bend towards the base can be connected (inserted) to a second pipe of a second size (e.g., size 75) that is larger than the first size. In this case, the second pipe of the second size is inserted beyond the bend. This allows for easy positioning of the connection point to the completed insertion point into the second pipe by visually inspecting the bend, thereby facilitating installation.

[0107] <4> the above <1> from <3> In any one of the drainage members, a fixing portion may be provided for fixing to the outer surface of the second pipe.

[0108] With the drainage member, the fixing part can be fixed to the outer surface of the second pipe, thereby tightening the second pipe at the fixing part. As a result, the second pipe can be properly compressed at the fixing part. This allows rainwater to be sealed inside the second pipe. In other words, it makes it difficult for air to enter the rainwater, thereby inducing a siphon effect. Consequently, rainwater can be properly drained by the siphon effect.

[0109] <5> the above <1> from <3> In any one of the drainage members, an overflow joint is provided in the first pipe, and the overflow joint may include a water channel connected to the second pipe for draining rainwater, an introduction channel for guiding the rainwater to the outside of the water channel, and a discharge channel for guiding the rainwater guided from the introduction channel downward.

[0110] According to the drainage component, for example, if rainfall increases and rainwater overflows into the drainage pipe of the overflow fitting, the overflowing rainwater can be guided to the outside of the drainage pipe by the intake channel. Furthermore, the rainwater guided to the outside of the drainage pipe can be discharged downwards by the discharge channel. This prevents the rainwater overflowing into the drainage pipe of the overflow fitting from overflowing to the upstream side of the second pipe (for example, the roof of the building).

[0111] <6> the above <5> The drainage member may include an expansion joint interposed between the first pipe and the overflow joint.

[0112] In the drainage component, an expansion joint is interposed between the first pipe and the overflow joint. This allows the expansion joint to absorb, for example, the thermal expansion of the first pipe and the thermal expansion of the overflow joint.

[0113] <7> the above <6> In the drainage member relating to this, the overflow joint may be located downstream of the rib.

[0114] In the drainage system, the overflow joint is positioned downstream of the rib. Therefore, for example, if rainfall increases and rainwater overflows into the drainage pipeline, the overflow joint can direct the overflow water downwards. This prevents the overflow water from flowing upstream of the rib. Consequently, the siphon effect induced by the rib can be maintained, allowing for proper drainage of rainwater.

[0115] <8> A rainwater drainage system according to one aspect of the present invention includes a rainwater drainage pipe in which a second pipe is arranged inside a first pipe, and the above connected to the rainwater drainage pipe. <1> It comprises the drainage member described above.

[0116] According to the rainwater drainage system, by connecting drainage components to the rainwater drainage pipe, rainwater can be properly drained by the siphon effect.

[0117] <9> A building according to one aspect of the present invention includes a rooftop and a second pipe for draining rainwater from the rooftop through the inside of the second pipe. <8> It includes the rainwater drainage system described above.

[0118] According to the building, it is equipped with a rainwater drainage system that drains rainwater from the roof. This allows the rainwater to flow down properly through the siphon effect.

[0119] <10> A method for constructing a rainwater drainage system according to one aspect of the present invention is as described above. <8> A method for constructing a rainwater drainage system as described above, comprising: step 1 of cutting the first pipe; step 2 of placing the second pipe inside the first pipe from the upstream side; and step 3 of connecting the drainage member to the first pipe and the second pipe.

[0120] According to the construction method for the rainwater drainage system, the first pipe is cut, and the second pipe is placed inside from the upstream side, and drainage components are connected to the first and second pipes. This completes the construction of the rainwater drainage system. According to the construction method for the rainwater drainage system, the rainwater drainage system can be easily constructed. Furthermore, by installing a rainwater drainage system, rainwater can be properly drained through the siphon effect.

[0121] <11> A rainwater drainage system according to one aspect of the present invention comprises a rainwater drainage pipe in which a second pipe is arranged inside a first pipe and which has been rehabilitated by the second pipe, and a drainage member connected to the rainwater drainage pipe that induces a siphon effect in rainwater passing inside the second pipe. [Explanation of Symbols]

[0122] 1, 100, 140, 160... Rainwater drainage system 3…Rainwater drain pipe 4,102,142,162… Drainage components 6…First tube 7...Second tube 16…Expansion joint 35,163… Induced sockets 36... Overflow fitting 41... Ring section 42,166... ​​Ribs 45...Connection part 52,167…Slope part 54…Part 1 55... Bending point (bending section) 56…Second part 67…Introduction channel 68… Discharge channel 105,145,150,164 Fixed part 200... Buildings H3…Flowing water pipe W1, W2... Rib width θ1…1st tilt angle (tilt angle) θ2…Second tilt angle (tilt angle)

Claims

1. A drainage member connected to a rainwater drainage pipe in which a second pipe is arranged inside a first pipe, The annular portion connected to the first pipe, The annular portion comprises a rib formed on the inner surface of the annular portion, The rib has a connecting portion that is connected to the inside of the second pipe. Drainage component.

2. The aforementioned connecting portion has a sloping portion that narrows in width towards the tip. The drainage member according to claim 1.

3. The aforementioned inclined portion is The drainage member has a bent portion in which the angle of inclination changes with respect to the pipe axis, The drainage member according to claim 2.

4. The second pipe is provided with a fixing part that is fixed to the outer surface, A drainage member according to any one of claims 1 to 3.

5. The first pipe is provided with an overflow fitting, The aforementioned overflow fitting is, A drainage pipe connected to the second pipe mentioned above for draining rainwater, An introduction channel for guiding the rainwater to the outside of the aforementioned water pipeline, The system includes a discharge channel for directing the rainwater introduced from the introduction channel downwards. A drainage member according to any one of claims 1 to 3.

6. An expansion joint is interposed between the first pipe and the overflow joint. The drainage member according to claim 5.

7. The overflow joint is located downstream of the rib. The drainage member according to claim 6.

8. A rainwater drainage pipe in which a second pipe is placed inside a first pipe, The drainage member according to claim 1 is connected to the rainwater drainage pipe, Rainwater drainage system.

9. The rooftop and, A rainwater drainage system according to claim 8, which drains rainwater from the rooftop through the inside of the second pipe, building.

10. A method for constructing a rainwater drainage system according to claim 8, Step 1 involves cutting the first pipe, Step 2 involves placing the second pipe inside the first pipe from the upstream side, Step 3 includes connecting the drainage member to the first pipe and the second pipe, Construction methods for rainwater drainage systems.

Images