Projection member, piping member and piping system

JP2025074356A5Pending Publication Date: 2026-03-05PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO LTD
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Patent Information

Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Filing Date
2025-03-06
Publication Date
2026-03-05

AI Technical Summary

Technical Problem

Existing piping systems face challenges in improving flow rates while maintaining a compact size, as larger elbows are required to enhance flow rates, leading to increased size and potential aesthetic issues.

Method used

The introduction of protruding members within straight tubes downstream of bent tubes, which partially reduce the cross-sectional area and feature a main surface and side surfaces with separation walls to promote flow separation and reattachment, thereby improving flow rates while allowing for miniaturization.

Benefits of technology

This configuration enhances flow rates by reducing pressure loss and allowing for a more compact design, addressing the trade-off between flow rate and system size.

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Abstract

To provide a projection member, a piping member, and a piping system that can improve a flow rate while enabling miniaturization.SOLUTION: A projection member 6-1 is disposed in a straight pipe (a vertical pipe 3) which is disposed downstream of a bent pipe 5-1 that changes a direction of a flow path and partially reduces a flow path cross-sectional area of the straight pipe (the vertical pipe 3). The projection member 6-1 includes: a main surface 61 which extends from a first end 6a directed to the upstream side toward a second end 6b directed to the downstream side, and is directed to the center side of the straight pipe (the vertical pipe 3) as viewed from a direction of a central axis C3 of the straight pipe (the vertical pipe 3); a first side surface 62 and a second side surface 63 which are located on both sides of the main surface 61 as viewed from the direction of the central axis C3 of the straight pipe (the vertical pipe 3); a first separation wall 64 which is located between the main surface 61 and the first side surface 62 to promote separation of a flow F1 along the main surface 61 and a flow F2 along the first side surface 62; and a second separation wall 65 which is located between the main surface 61 and the second side surface 63 to promote separation of the flow F1 along the main surface 61 and a flow F3 along the second side surface 63.SELECTED DRAWING: Figure 5
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Description

[Technical field]

[0001] The present disclosure relates to a projection member, a piping member, and a piping system. [Background technology]

[0002] Patent Document 1 discloses a siphon gutter system. The siphon gutter system disclosed in Patent Document 1 includes an eaves gutter, a siphon generating section that includes a cylindrical section penetrating a water collection port formed on the bottom surface of the eaves gutter and generates a siphon phenomenon, and an elbow. The elbow is installed downstream of the siphon gutter system. The elbow includes a curved pipe section and receiving ports provided on both ends of the curved pipe section. When viewed in a cross section on a plane including the pipe axis of the curved pipe section, the radius of curvature of the inner peripheral surface on the inner peripheral side is greater than 64 mm and smaller than 100 mm. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-120068 A Summary of the Invention [Problem to be solved by the invention]

[0004] The technique disclosed in Patent Document 1 is expected to improve the flow rate, but the elbow becomes relatively large.

[0005] The present disclosure provides a projection member, a piping member, and a piping system that can improve flow rate while allowing for miniaturization. [Means for solving the problem]

[0006] A protrusion member according to one embodiment of the present disclosure is a protrusion member that is disposed within a straight pipe that is located downstream of a bent pipe that changes the direction of the flow path, thereby partially reducing the flow path cross-sectional area of ​​the straight pipe, and extends from a first end facing the upstream side to a second end facing the downstream side, and is equipped with a main surface that faces the center of the straight pipe when viewed from the direction of the central axis of the straight pipe, a first side surface and a second side surface on either side of the main surface when viewed from the direction of the central axis of the straight pipe, a first separation wall that is between the main surface and the first side surface and promotes separation of the flow along the main surface and the flow along the first side surface, and a second separation wall that is between the main surface and the second side surface and promotes separation of the flow along the main surface and the flow along the second side surface.

[0007] A piping member according to one aspect of the present disclosure includes the above-described protrusion member and a straight pipe.

[0008] A piping system according to one embodiment of the present disclosure includes a vertical pipe fixed to a wall of a building, a horizontal pipe between a rainwater collection port from the building and the vertical pipe, a first bent pipe between the horizontal pipe and the vertical pipe, a second bent pipe between the collection port and the horizontal pipe, and the one or more protruding members. The one or more protruding members are arranged such that at least a part of the horizontal pipe or the vertical pipe is a straight pipe. Effect of the Invention

[0009] Aspects of the present disclosure can improve flow rates while allowing for compactness. [Brief description of the drawings]

[0010] [Figure 1] Schematic diagram of a piping system according to a first embodiment. [Diagram 2] FIG. 1 is a perspective view of a piping member of a piping system according to a first embodiment; [Diagram 3] FIG. 1 is an exploded perspective view of a piping member according to a first embodiment; [Figure 4] 1 is a cross-sectional view of a piping member according to a first embodiment. [Diagram 5] Cross section of line AA in Figure 4 [Figure 6] FIG. 1 is a cross-sectional view of a piping member according to a first embodiment, in which a part of the piping member is cut away. [Figure 7]FIG. 1 is a plan view of a piping member according to a first embodiment; [Figure 8] FIG. 1 is a bottom view of a piping member according to a first embodiment; [Figure 9] Cross section of line IX-IX in Figure 5 [Figure 10] Cross-sectional view of line XX in Figure 5 [Figure 11] Cross-sectional view of line XI-XI in Figure 5 [Figure 12] Sectional view of line XII-XII in Figure 5 [Figure 13] Cross-sectional view of line XIII-XIII in Figure 5 [Figure 14] 1 is a diagram showing a simulation of pressure distribution in a piping member of a comparative example; [Figure 15] Schematic diagram of a piping system according to a second embodiment. [Figure 16] FIG. 13 is a perspective view of a piping member according to a second embodiment; [Figure 17] FIG. 13 is an exploded perspective view of a piping member according to a second embodiment. [Figure 18] 11 is a cross-sectional view of a piping member according to a second embodiment. [Figure 19] Cross section of line BB in Figure 18 [Figure 20] FIG. 11 is a cross-sectional view of a piping member according to a second embodiment. [Figure 21] FIG. 11 is a plan view of a piping member according to a second embodiment; [Figure 22] FIG. 11 is a bottom view of the piping member according to the second embodiment; [Figure 23] FIG. 1 is a comparison diagram of a protruding member according to a second embodiment and a protruding member according to a first embodiment. [Figure 24] Graph showing change in pressure loss due to the protrusion member according to the second embodiment compared to the protrusion member according to the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] [1. Embodiment] Hereinafter, the embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed explanation than necessary may be omitted. For example, detailed explanation of already well-known matters or duplicate explanation of substantially the same configuration may be omitted. This is to avoid the following explanation becoming unnecessarily redundant and to facilitate understanding by those skilled in the art. Note that the inventor(s) provide the attached drawings and the following explanation so that those skilled in the art can fully understand the present disclosure, and do not intend for them to limit the subject matter described in the claims.

[0012] Unless otherwise specified, the positional relationships such as up, down, left, and right are based on the positional relationships shown in the drawings. Each figure described in the following embodiments is a schematic diagram, and the ratio of the size and thickness of each component in each figure does not necessarily reflect the actual dimensional ratio. Furthermore, the dimensional ratio of each element is not limited to the ratio shown in the drawings.

[0013] In the following description, when it is necessary to distinguish between multiple components, prefixes such as "first" and "second" are added to the names of the components. However, when the components can be distinguished from one another by the symbols added to them, the prefixes such as "first" and "second" may be omitted in consideration of readability of the text.

[0014] [1.1 First embodiment] [1.1.1 Configuration] FIG. 1 is a schematic diagram of a piping system 1 according to a first embodiment. The piping system 1 is used as a drainage system. The piping system 1 is a gutter system that receives rainwater from a roof 11a of a building 11 and drains it to a manhole 21 on the ground 20. The piping system 1 forms a flow path for rainwater. The rainwater collected in the manhole 21 flows out from the manhole 21 to a storm water pipe through a buried pipe 22. The building 11 is, for example, a non-residential facility such as a store, an office, a factory, a building, a school, a welfare facility, or a hospital, and a residential facility such as a detached house, an apartment building, or each dwelling unit of a detached house or an apartment building. The non-residential facility also includes a theater, a movie theater, a public hall, an amusement park, a complex, a department store, a hotel, an inn, a kindergarten, a library, a museum, an art museum, an underground shopping mall, a station, an airport, and the like.

[0015] The piping system 1 includes an eaves gutter 2, a vertical pipe 3, a horizontal pipe 4, bent pipes 5-1 and 5-2, protruding members 6-1 and 6-2, a vertical pipe 7, and a drain 8.

[0016] The eaves gutter 2 receives rainwater from the roof 11a of the building 11. The eaves gutter 2 is installed under the roof 11a of the building 11. As an example, the eaves gutter 2 is arranged at the eaves of the roof 11a. In particular, the eaves gutter 2 is arranged so as to extend along the eaves of the roof 11a. The eaves gutter 2 is in the shape of a long barrel. The eaves gutter 2 has a bottom wall 2a. A water collection port 2b is formed in the bottom wall 2a according to the overall design of the piping system 1. The water collection port 2b is, for example, a circular opening. The water collection port 2b is also called a drain or a drop port. As an example, the eaves gutter 2 may be formed by extrusion molding of a resin material. The eaves gutter 2 may include a core material for reinforcing the strength of the entire eaves gutter 2. The core material may be made of, for example, metal. As another example, the eaves gutter 2 may be formed of a metal plate, for example, a steel plate (also called a coil).

[0017] The drain 8 is disposed at the water collection port 2b of the eaves gutter 2. The drain 8 reduces the generation of vortexes and air entrainment at the water collection port 2b. The drain 8 may contribute to the generation of the siphon phenomenon. The drain 8 may have a known configuration.

[0018] The standpipe 3 defines a vertical flow path. In a gutter system, the standpipe 3 is also called a downspout. The standpipe 3 is installed to drain rainwater from the water collection port 2b. The standpipe 3 allows rainwater from the water collection port 2b to flow vertically. The standpipe 3 is straight. The cross section perpendicular to the central axis C3 of the standpipe 3 is circular. The standpipe 3 is arranged so that the direction of the central axis C3 of the standpipe 3 coincides with the up-down direction (vertical direction). In FIG. 1, the standpipe 3 is fixed to the wall surface 11b of the building 11 by support brackets 35a, 35b, and 35c. The standpipe 3 has an upstream end 3a and a downstream end 3b. The upstream end 3a is the end of the standpipe 3 that is connected to the water collection port 2b (the upper end in FIG. 1). The downstream end 3b is the end of the standpipe 3 that is inserted into the manhole 21 (the lower end in FIG. 1). In FIG. 1, a drain pipe cover 34 is arranged so that rainwater does not flow into the manhole 21 through a gap between the standpipe 3 and the manhole 21. As an example, the material of the standpipe 3 is rigid polyvinyl chloride. The dimensions of the standpipe 3, for example, the outer shape and thickness, may be set in accordance with the standard for rigid polyvinyl chloride pipes (general) of JIS K 6741 "rigid polyvinyl chloride pipes."

[0019] The building 11 has a relatively long eaves. If the standpipe 3 is directly connected to the water collection port 2b in the building 11, the distance between the standpipe 3 and the wall surface 11b of the building 11 will become large, and the construction standard for the standpipe 3 may not be met. In the piping system 1, the standpipe 3 is not directly connected to the water collection port 2b, but is connected to the water collection port 2b via the horizontal pipe 4 and the bent pipes 5-1 and 5-2. The piping system 1 has a structure that is more suitable for a building 11 with long eaves.

[0020] The horizontal pipe 4 defines a flow path in a direction intersecting the vertical direction. In the gutter system, the horizontal pipe 4 is also called a call gutter. The horizontal pipe 4 is a part for flowing rainwater from the building 11 from the water collection port 2b to the vertical pipe 3. The horizontal pipe 4 is between the rainwater collection port 2b of the building 11 and the vertical pipe 3. The horizontal pipe 4 is a straight pipe. The cross section perpendicular to the central axis C4 of the horizontal pipe 4 is circular. The horizontal pipe 4 is fixed so that the direction of the central axis C4 of the horizontal pipe 4 is inclined with respect to the up-down direction (vertical direction). The horizontal pipe 4 has an upstream end 4a and a downstream end 4b. The upstream end 4a is the end connected to the water collection port 2b in the horizontal pipe 4 (the left end in FIG. 1). The downstream end 4b is the end connected to the vertical pipe 3 in the horizontal pipe 4 (the right end in FIG. 1). As an example, the material of the horizontal pipe 4 is rigid polyvinyl chloride. The dimensions of the horizontal pipe 4, for example, the outer diameter and thickness, may be set in accordance with the standard for rigid polyvinyl chloride pipes (general) of JIS K 6741 "rigid polyvinyl chloride pipes."

[0021] The bent pipes 5-1 and 5-2 change the direction of the flow path. The bent pipes 5-1 and 5-2 are connection joints that connect flow paths with different directions, such as a vertical pipe and a horizontal pipe. Each of the bent pipes 5-1 and 5-2 has sockets 51 and 52 to which upstream and downstream piping members are respectively connected, and a bent portion 50 that connects the sockets 51 and 52 to each other. The angle between the central axes of the sockets 51 and 52 is, for example, 91.17° as specified in JIS K 6739 "Rigid polyvinyl chloride pipe joints for drainage". As an example, the material of the bent pipes 5-1 and 5-2 is, for example, rigid polyvinyl chloride. The dimensions of the bent pipes 5-1 and 5-2 may be set, for example, in accordance with the standard of JIS K 6739 "Rigid polyvinyl chloride pipe joints for drainage". The bent pipes 5-1 and 5-2 may be 90° bent elbows (so-called DL) as defined in JIS K 6739.

[0022] The bent pipe 5-1 is a first bent pipe that connects the vertical pipe 3 and the horizontal pipe 4. The bent pipe 5-1 connects the upstream end 3a of the vertical pipe 3 to the downstream end 4b of the horizontal pipe 4. In the bent pipe 5-1, the downstream end 4b of the horizontal pipe 4 is connected to the socket 51, and the upstream end 3a of the vertical pipe 3 is connected to the socket 52. The bent pipe 5-1 does not necessarily have to be a member that directly connects the upstream end 3a of the vertical pipe 3 to the downstream end 4b of the horizontal pipe 4, but may be a member that indirectly connects the upstream end 3a of the vertical pipe 3 to the downstream end 4b of the horizontal pipe 4 via another member.

[0023] The bent pipe 5-2 is a second bent pipe that connects the water collection port 2b and the horizontal pipe 4. The bent pipe 5-2 connects the upstream end 4a of the horizontal pipe 4 to the water collection port 2b. In the bent pipe 5-2, the water collection port 2b is connected to the receiving port 51, and the upstream end 4a of the horizontal pipe 4 is connected to the receiving port 52. The bent pipe 5-2 does not necessarily have to be a member that directly connects the upstream end 4a of the horizontal pipe 4 to the water collection port 2b, but may be a member that indirectly connects the upstream end 4a of the horizontal pipe 4 to the water collection port 2b via another member.

[0024] The standpipe 7 defines a vertical flow path. The standpipe 7 allows rainwater to flow vertically from the water collection port 2b. The standpipe 7 is connected to the drain 2c and is disposed downstream of the water collection port 2b. The standpipe 7 is disposed between the water collection port 2b and the bent pipe 5-2. The standpipe 7 is straight. The cross section perpendicular to the central axis of the standpipe 7 is circular. The standpipe 7 is disposed so that the direction of the central axis of the standpipe 7 coincides with the up-down direction (vertical direction). The standpipe 7 has an upstream end 7a and a downstream end 7b. The upstream end 7a is the end of the standpipe 7 that is connected to the water collection port 2b (the upper end in FIG. 1). The downstream end 7b is the end of the standpipe 7 that is connected to the receiving port 51 of the bent pipe 5-2 (the lower end in FIG. 1). As an example, the material of the upright pipe 7 is rigid polyvinyl chloride. The dimensions of the upright pipe 7, for example, the outer shape and thickness, may be set in accordance with the standard for rigid polyvinyl chloride pipes (general) of JIS K 6741 "rigid polyvinyl chloride pipes."

[0025] The protruding members 6-1 and 6-2 are disposed in a straight pipe disposed downstream of a bent pipe that changes the direction of the flow path, and are used to partially reduce the flow path cross-sectional area of ​​the straight pipe. In the piping system 1, the vertical pipe 3 is a straight pipe disposed downstream of the bent pipe 5-1 that changes the direction of the flow path, and the horizontal pipe 4 is a straight pipe disposed downstream of the bent pipe 5-2 that changes the direction of the flow path. The protruding member 6-1 is a first protruding member disposed so that at least a part of the vertical pipe 3 is a straight pipe. In this embodiment, at least a part of the vertical pipe 3 is the entire vertical pipe 3. The protruding member 6-2 is a second protruding member disposed so that at least a part of the horizontal pipe 4 is a straight pipe. In this embodiment, at least a part of the horizontal pipe 4 is the entire horizontal pipe 4.

[0026] The protrusion members 6-1, 6-2, together with the vertical pipe 3 and horizontal pipe 4, which are straight pipes in which the protrusion members 6-1, 6-2 are arranged, respectively constitute piping members 10-1, 10-2. In this embodiment, the piping member 10-1 including the protrusion member 6-1 and the vertical pipe 3 is the first piping member, and the piping member 10-2 including the protrusion member 6-2 and the horizontal pipe 4 is the second piping member.

[0027] The protrusion members 6-1 and 6-2 have the same configuration. Therefore, the piping members 10-1 and 10-2 have substantially the same configuration, although there is a difference between the vertical pipe 3 and the horizontal pipe 4. The following mainly describes the piping member 10-1 in detail. A person skilled in the art can easily understand that the description of the piping member 10-1 is also a description of the piping member 10-2 by replacing the description related to the vertical pipe 3 with the description related to the horizontal pipe 4.

[0028] Fig. 2 is a perspective view of a configuration example of the piping member 10-1, and Fig. 3 is an exploded perspective view of the piping member 10-1. As can be seen from Figs. 2 and 3, the piping member 10-1 includes a vertical pipe 3 and a protruding member 6-1.

[0029] 3, the protruding member 6-1 has a size, that is, a length, a width, and a height (thickness), that allows it to be placed inside the riser pipe 3. The material of the protruding member 6-1 is, for example, hard polyvinyl chloride.

[0030] The protruding member 6-1 has a first end 6a and a second end 6b. The first end 6a and the second end 6b are both ends in the longitudinal direction of the protruding member 6-1. The longitudinal direction of the protruding member 6-1 coincides with the direction of the central axis C3 of the vertical pipe 3. The first end 6a faces the upstream side, and the second end 6b faces the downstream side. In the protruding member 6-1, a fluid flow is generated from the first end 6a to the second end 6b.

[0031] FIG. 4 is a cross-sectional view of the piping member 10-1. FIG. 5 is a cross-sectional view taken along line AA in FIG. 4. FIG. 6 is a cross-sectional view in which a portion of the piping member 10-1 is cut away. FIG. 7 is a plan view of the piping member 10-1. FIG. 8 is a bottom view of the piping member 10-1. FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. 5. FIG. 10 is a cross-sectional view taken along line XX in FIG. 5. FIG. 11 is a cross-sectional view taken along line XI-XI in FIG. 5. FIG. 12 is a cross-sectional view taken along line XII-XII in FIG. 5. FIG. 13 is a cross-sectional view taken along line XIII-XIII in FIG. 5.

[0032] As shown in Fig. 4, the protruding member 6-1 has a contact surface 60 that contacts the inner circumferential surface 30a of the standpipe 3. As shown in Fig. 7 and Fig. 8, the contact surface 60 has a convex shape when viewed from the direction of the central axis C3 of the standpipe 3. The radius of curvature of the contact surface 60 is set based on the radius of curvature of the inner circumferential surface 30a so that no gap is substantially generated between the contact surface 60 and the inner circumferential surface 30a of the standpipe 3.

[0033] As shown in FIG. 4 to FIG. 8, the protruding member 6-1 has a main surface 61 and first and second side surfaces 62, 63. The main surface 61 and the first and second side surfaces 62, 63 are on the opposite side of the protruding member 6-1 to the contact surface 60, and can come into contact with the fluid flowing in the standpipe 3. As shown in FIG. 4 to FIG. 6, the main surface 61 extends from the first end 6a to the second end 6b. As shown in FIG. 7 and FIG. 8, the main surface 61 faces the center side of the standpipe 3 when viewed from the direction of the central axis C3 of the standpipe 3. The first side surface 62 and the second side surface 63 are on both sides of the main surface 61 when viewed from the direction of the central axis C3 of the standpipe 3. In FIG. 7, the first side surface 62 is on the left side of the main surface 61, and the second side surface 63 is on the right side of the main surface 61.

[0034] In the protrusion member 6-1, the main surface 61 and the first and second side surfaces 62, 63 may come into contact with the fluid flowing in the upright pipe 3. As shown in Fig. 5, the protrusion member 6-1 causes a flow F1 along the main surface, a flow F2 along the first side surface 62, and a flow F3 along the second side surface 63. Since the main surface 61 and the first and second side surfaces 62, 63 may come into contact with the fluid, it is preferable that the surface roughness of the main surface 61 and the first and second side surfaces 62, 63 be small, since this is expected to improve the flow rate.

[0035] The protrusion member 6-1 has a first separation wall 64 for promoting separation of the flow F1 and the flow F2. The presence of the first separation wall 64 can facilitate separation of the flow F2 from the flow F1. The first separation wall 64 is between the main surface 61 and the first side surface 62. In this embodiment, the first separation wall 64 is a boundary portion between the main surface 61 and the first side surface 62. In other words, the boundary portion between the main surface 61 and the first side surface 62 constitutes a wall between a flow path having the main surface 61 as a bottom surface and a flow path having the first side surface 62 as a bottom surface. The first separation wall 64 can be formed by having both the main surface 61 and the first side surface 62 have a concave shape.

[0036] The protrusion member 6-1 has a second separation wall 65 to promote separation of the flow F1 and the flow F3. The presence of the second separation wall 65 can facilitate separation of the flow F3 from the flow F1. The second separation wall 65 is between the main surface 61 and the second side surface 63. In this embodiment, the second separation wall 65 is a boundary portion between the main surface 61 and the second side surface 63. In other words, the boundary portion between the main surface 61 and the second side surface 63 constitutes a wall between a flow path having the main surface 61 as a bottom surface and a flow path having the second side surface 63 as a bottom surface. The second separation wall 65 can be formed by having both the main surface 61 and the second side surface 63 have a concave shape.

[0037] As can be seen from FIGS. 4, 5, and 7 to 13, the shape (cross-sectional shape) of the protruding member 6-1 seen from the direction of the central axis C3 of the vertical pipe 3 changes along the direction of the central axis C3 of the vertical pipe 3.

[0038] As shown in FIG. 4, the height of the protruding member 6-1 changes along the direction of the central axis C3 of the upright pipe 3. In this embodiment, the protruding member 6-1 has a top 6c between the first end 6a and the second end 6b. The top 6c is the highest part of the protruding member 6-1. The height of the protruding member 6-1 increases monotonically from the first end 6a to the top 6c. The height of the protruding member 6-1 decreases monotonically from the top 6c to the second end 6b. The protruding member 6-1 makes the flow path cross-sectional area of ​​the upright pipe 3 the smallest at the top 6c.

[0039] As shown in FIG. 4, in a cross section perpendicular to the width direction of the protruding member 6-1, the main surface 61 includes a curved shape that protrudes toward the second wall surface 30c at the top 6c. This can improve the flow rate. From another perspective, the main surface 61 only needs to have a shape that protrudes toward the second wall surface 30c so as to generate the Coanda effect on the downstream side of the bent pipe 5-1. In other words, the main surface 61 only needs to have a shape that generates the Coanda effect on the downstream side of the bent pipe 5-1. This can improve the flow rate while enabling miniaturization.

[0040] As can be seen from FIGS. 7 to 13, the shape of the main surface 61 as viewed from the direction of the central axis C3 of the vertical pipe 3 changes along the direction of the central axis C3 of the vertical pipe 3. As shown in FIG.

[0041] 7 and 9, when viewed from the direction of the central axis C3 of the vertical pipe 3, at least a part of the main surface 61 has a concave shape. At least a part of the main surface 61 is a portion of the main surface 61 on the first end 6a side. In other words, the main surface 61 has a concave shape at the first end 6a. When viewed from the direction of the central axis C3 of the vertical pipe 3, the radius of curvature of at least a part of the main surface 61 (the first end 6a) is equal to or smaller than the radius of curvature of the inner circumferential surface 30a of the vertical pipe 3. This reduces pressure loss in the protruding member 6-1.

[0042] As shown in Figs. 7 to 11, the main surface 61 has a concave shape at the first end 6a, but a convex shape at the second end 6b. That is, the shape of the main surface 61 as viewed from the direction of the central axis C3 of the vertical pipe 3 changes from a concave shape to a convex shape from the first end 6a to the second end 6b. This makes it easier for a flow to occur along the main surface 61 of the protruding member 6-1. In this embodiment, as shown in Fig. 11, the shape of the main surface 61 as viewed from the direction of the central axis C3 of the vertical pipe 3 is a convex shape at the top 6c. The shape of the main surface 61 as viewed from the direction of the central axis C3 of the vertical pipe 3 is a convex shape in the range from the top 6c to the second end 6b. In this embodiment, the protruding member 6-1 has a flat portion 6d between the first end 6a and the top 6c. As shown in Fig. 10, at the flat portion 6d, the main surface 61 has a planar shape as viewed from the direction of the central axis C3 of the vertical pipe 3.

[0043] In the range of the concave shape of the main surface 61, the center of the concave shape of the main surface 61, i.e., the lowest part of the concave shape, is located closer to the center than the ends in the width direction of the protrusion member 6-1. In the range of the convex shape of the main surface 61, the center of the convex shape of the main surface 61, i.e., the highest part of the convex shape, is located closer to the center than the ends in the width direction of the protrusion member 6-1. In this embodiment, the center of the convex shape of the main surface 61 coincides with the center in the width direction of the protrusion member 6-1.

[0044] As can be seen from FIGS. 7 to 13, the shapes of the first side surface 62 and the second side surface 63 when viewed from the direction of the central axis C3 of the vertical pipe 3 change along the direction of the central axis C3 of the vertical pipe 3.

[0045] 7 and 9, when viewed from the direction of the central axis C3 of the vertical pipe 3, at least a part of the first side surface 62 is concave. At least a part of the first side surface 62 is a portion of the first side surface 62 on the first end 6a side. In other words, the first side surface 62 is concave at the first end 6a. This reduces pressure loss in the protruding member 6-1.

[0046] 7 and 9, when viewed from the direction of the central axis C3 of the vertical pipe 3, at least a part of the second side surface 63 is concave. At least a part of the second side surface 63 is a portion of the second side surface 63 on the first end 6a side. In other words, the second side surface 63 is concave at the first end 6a. This reduces pressure loss in the protruding member 6-1.

[0047] The shape of the first side surface 62 as viewed from the direction of the central axis C3 of the vertical pipe 3 remains concave from the first end 6a toward the second end 6b. As can be seen from Fig. 11 to Fig. 13, the depth of the concave shape of the first side surface 62 becomes shallower from the apex 6c toward the second end 6b. This allows the flow F2 along the first side surface 62 to smoothly merge with the flow F1 along the main surface 61 on the downstream side of the protruding member 6-1.

[0048] The shape of the second side surface 63 as viewed from the direction of the central axis C3 of the vertical pipe 3 remains concave from the first end 6a to the second end 6b. As can be seen from Fig. 11 to Fig. 13, the depth of the concave shape of the second side surface 63 becomes shallower from the top 6c to the second end 6b. This allows the flow F3 along the second side surface 63 to smoothly merge with the flow F1 along the main surface 61 on the downstream side of the protruding member 6-1.

[0049] 5, in the protrusion member 6-1, the first side surface 62 and the second side surface 63 are symmetrical with respect to the center line of the protrusion member 6-1 along the central axis C3 of the vertical pipe 3. This can improve the flow rate.

[0050] As shown in FIG. 5, the width of the protruding member 6-1 changes along the direction of the central axis C3 of the upright pipe 3. The width of the protruding member 6-1 refers to the width of the protruding member 6-1 at the portion closest to the inner peripheral surface 30a of the upright pipe 3. In this embodiment, the width of the protruding member 6-1 corresponds to the width of the contact surface 60 of the protruding member 6-1. The protruding member 6-1 has a first portion 6e, a second portion 6f, and a third portion 6g between the first end 6a and the second end 6b, where the direction of the change in width changes. The first portion 6e is between the first end 6a and the apex 6c, more specifically, the flat portion 6d. The second portion 6f is between the apex 6c and the second end 6b. The third portion 6g is between the second portion 6f and the second end 6b. The width of the protruding member 6-1 increases monotonically from the first end 6a to the first portion 6e. The width of the protruding member 6-1 decreases monotonically from the first portion 6e to the second portion 6f. The width of the protruding member 6-1 increases monotonically from the second portion 6f to the third portion 6g. The width of the protruding member 6-1 decreases monotonically from the third portion 6g to the second end 6b. The width of the protruding member 6-1 is largest at the first portion 6e. As shown in FIG. 7, the maximum value of the width of the protruding member 6-1 as viewed from the direction of the central axis C3 of the vertical pipe 3 (the width at the first portion 6e) is W1. If the inner diameter of the vertical pipe 3 is d, 0.5d≦W1≦0.9d. Here, if the maximum value of the distance between the first partition wall 64 and the second partition wall 65 as viewed from the direction of the central axis C3 of the vertical pipe 3 is W2, 0.3d≦W2≦0.7d. W2≦W1.

[0051] The width of the main surface 61 narrows from the first end 6a to the second end 6b, at least from the first end 6a to the apex 6c. This configuration allows the flows F2 and F3 along the first side surface 62 and the second side surface 63 to smoothly merge with the flow F1 along the main surface 61 on the downstream side of the protruding member 6-1. In this embodiment, the width of the main surface 61 monotonically decreases from the first end 6a to the second end 6b.

[0052] The first side surface 62 includes a portion whose width increases from the first end 6a toward the second end 6b. More specifically, the portion of the first side surface 62 on the first end 6a side increases in width from the first end 6a toward the second end 6b. This configuration can reduce pressure loss. In this embodiment, the portion of the first side surface 62 on the first end 6a side includes the portion of the first side surface 62 from the first end 6a to the flat portion 6d.

[0053] The second side surface 63 includes a portion that becomes wider from the first end 6a toward the second end 6b. More specifically, the portion of the second side surface 63 on the first end 6a side becomes wider from the first end 6a toward the second end 6b. This configuration can reduce pressure loss. In this embodiment, the portion of the second side surface 63 on the first end 6a side includes the portion of the second side surface 63 from the first end 6a to the flat portion 6d.

[0054] The first separation wall 64 and the second separation wall 65 are formed on a part of the protruding member 6-1, not on the whole, in the direction of the central axis C3 of the standpipe 3. More specifically, the first separation wall 64 and the second separation wall 65 exist in a predetermined range from the first end 6a along the direction of the central axis C3 of the standpipe 3. The predetermined range is the range from the first end 6a to the flat portion 6d.

[0055] The distance between the first separation wall 64 and the second separation wall 65 becomes shorter from the first end 6a toward the second end 6b. This configuration separates the flows F2, F3 along the first side surface 62 and the second side surface 63 from the flow F1 along the main surface 61 on the upstream side of the protrusion member 6-1, and allows the flows F2, F3 along the first side surface 62 and the second side surface 63 to smoothly merge with the flow F1 along the main surface 61 on the downstream side of the protrusion member 6-1.

[0056] The heights of the first separation wall 64 and the second separation wall 65 decrease from the first end 6a toward the second end 6b. This configuration separates the flows F2, F3 along the first side surface 62 and the second side surface 63 from the flow F1 along the main surface 61 on the upstream side of the protrusion member 6-1, and allows the flows F2, F3 along the first side surface 62 and the second side surface 63 to smoothly merge with the flow F1 along the main surface 61 on the downstream side of the protrusion member 6-1.

[0057] Please refer to Figures 4 and 11. The diameter of the vertical pipe 3 is d, and the distance between the first end 6a and the second end 6b in the direction of the central axis C3 of the vertical pipe 3 is L (i.e., the length of the protruding member 6-1). In the protruding member 6-1, it is preferable that 0.5d ≦ L ≦ 5.0d. This can further reduce the occurrence of pressure loss due to separation on the downstream side from the bent pipe 5-1. Therefore, the flow rate can be improved while enabling miniaturization.

[0058] Please refer to FIG. 4. The top 6c of the protruding member 6-1 is the portion of the piping member 10-1 where the flow path cross-sectional area is the smallest. The distance between the first end 6a and the top 6c in the direction of the central axis C3 of the vertical pipe 3 is L1. In the protruding member 6-1, it is preferable that 0.1L≦L1≦0.5L. This can further reduce the occurrence of pressure loss caused by separation downstream from the bent pipe 5-1. Therefore, the flow rate can be improved while enabling miniaturization.

[0059] Please refer to FIG. 4. The distance between the top 6c and the second end 6b in the direction of the central axis C3 of the vertical pipe 3 is L2. L2=L-L1. In the protruding member 6-1, it is preferable that L2>L1. This can further reduce the occurrence of pressure loss caused by separation on the downstream side from the bent pipe 5-1. Therefore, the flow rate can be improved while enabling miniaturization.

[0060] See FIG. 11. When viewed from the direction of the central axis C3 of the vertical pipe 3, the distance between the top 6c of the protruding member 6-1 and the second wall surface 30c is defined as D1. In the protruding member 6-1, it is preferable that 0.60d≦D1≦0.95d. This can further reduce the occurrence of pressure loss caused by separation downstream from the bent pipe 5-1. Therefore, the flow rate can be improved while enabling miniaturization.

[0061] The height of the top 6c of the protruding member 6-1 as viewed from the direction of the central axis C3 of the vertical pipe 3 is defined as H1. H1=d-D1. It is preferable that 0.05d≦H1≦0.40d is satisfied for the protruding member 6-1. This can further reduce the occurrence of pressure loss caused by separation downstream from the bent pipe 5-1. Therefore, the flow rate can be improved while enabling miniaturization.

[0062] The maximum flow cross-sectional area of ​​the vertical pipe 3 is A. The maximum flow cross-sectional area A is calculated from the inner diameter d of the vertical pipe 3. In other words, A = π(d / 2) 2 The cross-sectional area of ​​the protruding member at the top 6c is A1. In the protruding member 6-1, it is preferable that A1 / A≦0.4. This can further reduce the occurrence of pressure loss caused by peeling downstream from the bent pipe 5-1. Therefore, the flow rate can be improved while enabling miniaturization. The minimum value of the flow path cross-sectional area in the piping member 10-1 is A2. A2 is the flow path cross-sectional area at the top 6c of the protruding member 6-1. A2=A-A1. In the protruding member 6-1, it is preferable that 0.6≦A2 / A<1. This can further reduce the occurrence of pressure loss caused by peeling downstream from the bent pipe 5-1. Therefore, the flow rate can be improved while enabling miniaturization.

[0063] As shown in FIG. 4, FIG. 6, and FIG. 7, the protruding member 6-1 has a contact end surface 66 at the first end 6a. In this embodiment, the inner diameter of the vertical pipe 3 is larger than the inner diameter of the bent portion 50 of the bent pipe 5-1. The contact end surface 66 is provided to fill the difference in inner diameter between the vertical pipe 3 and the bent portion 50 of the bent pipe 5-1. As shown in FIG. 4, the presence of the contact end surface 66 can reduce the step between the wall surface 50a on the inner periphery side of the bent portion 50 of the bent pipe 5-1 and the main surface 61 of the protruding member 6-1. This makes it difficult for the flow of fluid from the bent pipe 5-1 to be obstructed by the piping member 10-1.

[0064] As shown in FIG. 7, the protrusion member 6-1 has a protrusion 67. The protrusion 67 is used for joining or positioning the standpipe 3 and the protrusion member 6-1. The protrusion 67 is disposed on the contact surface 60. The protrusion 67 is shaped to fit into the recess 3c of the standpipe 3. In this embodiment, the standpipe 3 has a pair of recesses 3c on the edge of the upstream end 3a. The recesses 3c are formed as notches. The protrusion member 6-1 has a pair of protrusions 67 that fit into the pair of recesses 3c, respectively. The protrusion member 6-1 is positioned relative to the standpipe 3 by fitting the pair of protrusions 67 into the pair of recesses 3c, respectively.

[0065] In the piping member 10-1 described above, the protruding member 6-1 is disposed on the inner peripheral surface 30a of the standpipe 3. As a result, the flow path cross-sectional area of ​​the piping member 10-1 is not constant, and there is a reduced portion where the flow path cross-sectional area of ​​the piping member 10-1 is smaller than the cross-sectional area of ​​the standpipe 3. The protruding member 6-1 is located closer to the upstream end 3a of the standpipe 3 than the downstream end 3b of the standpipe 3. In this embodiment, the protruding member 6-1 is located at the upstream end 3a of the standpipe 3. In other words, the protruding member 6-1 reduces the flow path at the upstream end 3a of the standpipe 3 connected to the bent pipe 5-1.

[0066] The protruding member 6-1 is disposed so as to protrude from a first wall surface 30b on the inner periphery side of the vertical pipe 3 toward a second wall surface 30c on the outer periphery side of the vertical pipe 3. The first wall surface 30b is a portion of the inner periphery side of the bent pipe 5-1 on the inner periphery side of the vertical pipe 3 (for example, half of the inner periphery side). The second wall surface 30c is a portion of the inner periphery side of the bent pipe 5-1 on the inner periphery side of the vertical pipe 3 (for example, half of the outer periphery side). The inner periphery side 30a is composed of the first wall surface 30b and the second wall surface 30c.

[0067] Next, the function of the protruding member 6-1 in the piping member 10-1 will be described. The protruding member 6-1 is disposed in the vertical pipe 3 disposed downstream of the bent pipe 5-1. The bent pipe 5-1 directs water flowing in from the horizontal pipe 4 to the vertical pipe 3. When the direction of the water flow changes significantly in the bent pipe 5-1, pressure loss due to separation can be one of the factors that reduces the flow rate.

[0068] FIG. 14 is a diagram of a simulation of pressure distribution in the piping member 100 of the comparative example. The piping member 100 of the comparative example differs from the piping member 10-1 in that it does not have the protruding member 6-1. In FIG. 14, the darker the color, the lower the pressure. In particular, the pressure loss is large at the portion indicated by R in FIG. 14, and the presence of such a portion with a large pressure loss can be a major factor in the decrease in flow rate. The pressure loss at the portion indicated by R in FIG. 14 is considered to be caused by peeling. This peeling is caused by water separating from the first wall surface 30b of the piping member 100 downstream of the inner wall surface 50a of the bent pipe 5-1. That is, as shown by the arrow F in FIG. 14, the water flowing in from the upstream side initially flows along the pipe wall 200, but after the inner wall surface 50a of the bent pipe 5-1, it may separate from the first wall surface 30b of the piping member 100. Such peeling is likely to be noticeable, especially when the water flow speed is high. The faster the flow velocity, the wider the area where pressure loss occurs.

[0069] In this embodiment, the piping member 10-1 has a protruding member 6-1. The presence of the protruding member 6-1 is expected to (1) make it easier for water to flow along the pipe wall than when the protruding member 6-1 is not present, and (2) reduce the number of areas where pressure loss may occur. Therefore, the protruding member 6-1 can reduce the occurrence of pressure loss caused by separation downstream from the bent pipe 5-1, and improve the flow rate. The piping member 10-1 can be made smaller by simply providing the protruding member 6-1, unlike the technology described in Patent Document 1, because it is not necessary to increase the radius of curvature of the inner circumferential surface on the inner circumferential side of the bent pipe 5-1. Therefore, the protruding member 6-1 can improve the flow rate while making it possible to make the piping system 1 smaller. The protruding member 6-1 is located inside the vertical pipe 3, and the protruding member 6-1 is not noticeable when viewed as the piping system 1 as a whole. This is expected to improve the aesthetic appearance of the piping system 1 as a whole.

[0070] [1.1.2 Effects, etc.] The above-described protrusion members 6-1, 6-2 are arranged in the straight pipes (upright pipe 3, horizontal pipe 4) that are arranged downstream of the bent pipes 5-1, 5-2 that change the direction of the flow path, and partially reduce the flow path cross-sectional area of ​​the straight pipes. The protruding members 6-1 and 6-2 extend from a first end 6a facing the upstream side to a second end 6b facing the downstream side, and include a main surface 61 facing the center of the straight pipes (vertical pipe 3, horizontal pipe 4) as viewed from the direction of the central axes C3 and C4 of the straight pipes, a first side surface 62 and a second side surface 63 on both sides of the main surface 61 as viewed from the direction of the central axes C3 and C4 of the straight pipes (vertical pipe 3, horizontal pipe 4), a first separation wall 64 between the main surface 61 and the first side surface 62 to promote separation of the flow F1 along the main surface 61 and the flow F2 along the first side surface 62, and a second separation wall 65 between the main surface 61 and the second side surface 63 to promote separation of the flow F1 along the main surface 61 and the flow F3 along the second side surface 63. This configuration can improve the flow rate while enabling miniaturization.

[0071] In the protruding members 6-1 and 6-2, at least a part of the main surface 61 is concave when viewed from the direction of the central axes C3 and C4 of the straight pipes (the vertical pipe 3 and the horizontal pipe 4). This configuration reduces pressure loss in the protruding members 6-1 and 6-2.

[0072] In the protruding members 6-1 and 6-2, the radius of curvature of at least a part of the main surface 61 is equal to or smaller than the radius of curvature of the inner circumferential surface 30a of the straight pipes (upright pipe 3 and horizontal pipe 4) when viewed from the direction of the central axes C3 and C4 of the straight pipes (upright pipe 3 and horizontal pipe 4). This configuration reduces pressure loss in the protruding members 6-1 and 6-2.

[0073] In the protruding members 6-1 and 6-2, the shape of the main surface 61 when viewed from the direction of the central axes C3 and C4 of the straight pipes (the vertical pipe 3 and the horizontal pipe 4) changes from a concave shape to a convex shape from the first end 6a to the second end 6b. This configuration makes it easier to generate a flow F1 along the main surface 61 of the protruding members 6-1 and 6-2.

[0074] The protruding members 6-1 and 6-2 have a top 6c between the first end 6a and the second end 6b, which minimizes the flow path cross-sectional area of ​​the straight pipes (the vertical pipe 3 and the horizontal pipe 4). The shape of the main surface 61 of the straight pipes (the vertical pipe 3 and the horizontal pipe 4) as viewed from the direction of the central axes C3 and C4 of the straight pipes (the vertical pipe 3 and the horizontal pipe 4) is convex at the top 6c. This configuration makes it easier to generate a flow along the main surface 61 of the protruding members 6-1 and 6-2.

[0075] The protruding members 6-1 and 6-2 have a top 6c between the first end 6a and the second end 6b, which minimizes the flow path cross-sectional area of ​​the straight pipes (the vertical pipe 3 and the horizontal pipe 4). The main surface 61 narrows in width from the first end 6a to the top 6c at least from the first end 6a to the second end 6b. This configuration allows the flows F2 and F3 along the first side surface 62 and the second side surface 63 to smoothly merge with the flow F1 along the main surface 61 on the downstream side of the protruding members 6-1 and 6-2.

[0076] In the protruding members 6-1 and 6-2, at least a part of the first side surface 62 and the second side surface 63 is concave when viewed from the direction of the central axes C3 and C4 of the straight pipes (the vertical pipe 3 and the horizontal pipe 4). This configuration reduces pressure loss in the protruding members 6-1 and 6-2.

[0077] The protruding members 6-1 and 6-2 have a top 6c between the first end 6a and the second end 6b that minimizes the flow path cross-sectional area of ​​the straight pipes (the vertical pipe 3 and the horizontal pipe 4). The first side surface 62 and the second side surface 63 have a concave shape whose depth becomes shallower from the top 6c toward the second end 6b. This configuration allows the flows F2 and F3 along the first side surface 62 and the second side surface 63 to smoothly merge with the flow F1 along the main surface 61 on the downstream side of the protruding members 6-1 and 6-2.

[0078] In the protruding members 6-1 and 6-2, the first side surface 62 and the second side surface 63 are symmetrical with respect to the center lines of the protruding members 6-1 and 6-2 that are aligned with the central axes C3 and C4 of the straight pipes (the vertical pipe 3 and the horizontal pipe 4). This configuration can improve the flow rate.

[0079] In the protruding members 6-1 and 6-2, the width of the first end 6a side of the first side surface 62 and the second side surface 63 increases from the first end 6a toward the second end 6b. This configuration can reduce pressure loss.

[0080] The protruding members 6-1 and 6-2 have a top 6c between the first end 6a and the second end 6b, which minimizes the flow path cross-sectional area of ​​the straight pipes (vertical pipe 3, horizontal pipe 4). If the distance between the first end 6a and the second end 6b in the direction of the central axes C3 and C4 of the straight pipes (vertical pipe 3, horizontal pipe 4) is L, and the distance between the first end and the top in the direction of the central axis of the straight pipe is L1, then 0.1L≦L1≦0.5L. This configuration can improve the flow rate.

[0081] The protruding members 6-1 and 6-2 have a top 6c between the first end 6a and the second end 6b, which minimizes the flow path cross-sectional area of ​​the straight pipes (upright pipe 3 and horizontal pipe 4). If the maximum flow path cross-sectional area of ​​the straight pipes (upright pipe 3 and horizontal pipe 4) is A and the cross-sectional area of ​​the protruding members 6-1 and 6-2 at the top 6c is A1, then A1 / A≦0.4. This configuration can improve the flow rate.

[0082] In the protruding members 6-1 and 6-2, if the inner diameter of the straight pipes (vertical pipe 3 and horizontal pipe 4) is d and the distance between the first end 6a and the second end 6b in the direction of the central axes C3 and C4 of the straight pipes (vertical pipe 3 and horizontal pipe 4) is L, then 0.5d≦L≦5.0d is satisfied. This configuration can improve the flow rate.

[0083] The piping members 10-1 and 10-2 described above include the protruding members 6-1 and 6-2 and straight pipes (the vertical pipe 3 and the horizontal pipe 4). This configuration can improve the flow rate while enabling miniaturization.

[0084] The piping system 1 described above includes a vertical pipe 3 fixed to a wall surface 11b of a building 11, a horizontal pipe 4 between the vertical pipe 3 and a water collection port 2b for rainwater from the building 11, a first bent pipe 5-1 between the horizontal pipe 4 and the vertical pipe 3, a second bent pipe 5-2 between the water collection port 2b and the horizontal pipe 4, and protruding members 6-1 and 6-2. The protruding member 6-1 is arranged such that at least a portion of the vertical pipe 3 is a straight pipe, and the protruding member 6-2 is arranged such that at least a portion of the horizontal pipe 4 is a straight pipe. This configuration can improve the flow rate while enabling miniaturization.

[0085] [1.2 Second embodiment] [1.2.1 Configuration] 15 is a schematic diagram of a piping system 1A according to embodiment 2. The piping system 1A includes an eaves gutter 2, a vertical pipe 3A, a horizontal pipe 4A, bent pipes 5-1 and 5-2, protruding members 6A-1 and 6A-2, a vertical pipe 7, and a drain 8.

[0086] The vertical pipe 3A is composed of a plurality of piping members. The vertical pipe 3A includes straight pipes 31, 32 and a joint 33 that connects the straight pipes 31, 32 together. The vertical pipe 3A is composed of a plurality of piping members. The vertical pipe 3A includes straight pipes 31, 32 and a joint 33 that connects the straight pipes 31, 32 together. The straight pipe 31 is a downstream portion of the vertical pipe 3A, and the straight pipe 32 is an upstream portion of the vertical pipe 3A. In this embodiment, the straight pipe 31 is longer than the straight pipe 32. The first end (upper end in FIG. 15) of the straight pipe 32 defines the upstream end 3a of the vertical pipe 3A, the second end (lower end in FIG. 15) of the straight pipe 32 is connected to the first end (upper end in FIG. 15) of the straight pipe 31 via the connecting joint 33, and the second end (lower end in FIG. 15) of the straight pipe 31 defines the downstream end 3b of the vertical pipe 3A. As an example, the material of the straight pipes 31, 32 and the connecting joint 33 is rigid polyvinyl chloride. The dimensions of the straight pipes 31, 32, for example, the outer shape and thickness, may be set according to the standard for rigid polyvinyl chloride pipe (general) of JIS K 6741 "Rigid polyvinyl chloride pipe". The dimensions of the connecting joint 33, for example, the outer shape and thickness, may be set according to the standard for the socket of JIS K 6739 "Rigid polyvinyl chloride pipe joint for drainage".

[0087] The horizontal pipe 4A is composed of a plurality of piping members. The horizontal pipe 4A includes straight pipes 41 and 42 and a joint 43 that connects the straight pipes 41 and 42 together. The straight pipe 41 is a downstream portion of the horizontal pipe 4A, and the straight pipe 42 is an upstream portion of the horizontal pipe A. In this embodiment, the straight pipe 41 is longer than the straight pipe 42. The first end (left end in FIG. 15) of the straight pipe 42 defines the upstream end 4a of the horizontal pipe 4A, the second end (right end in FIG. 15) of the straight pipe 42 is connected to the first end (left end in FIG. 15) of the straight pipe 41 via the joint 43, and the second end (right end in FIG. 15) of the straight pipe 41 defines the downstream end 4b of the horizontal pipe 4A. As an example, the material of the straight pipes 41 and 42 and the joint 43 is rigid polyvinyl chloride. The dimensions of the straight pipes 41, 42, such as the outer shape and thickness, may be set in accordance with the standard for rigid polyvinyl chloride pipes (general) of JIS K 6741 "rigid polyvinyl chloride pipes." The dimensions of the connection joint 43, such as the outer shape and thickness, may be set in accordance with the standard for sockets of JIS K 6739 "rigid polyvinyl chloride pipe joints for drainage."

[0088] The protruding members 6A-1 and 6A-2 are disposed in a straight pipe disposed downstream of a bent pipe that changes the direction of the flow path, and are used to partially reduce the flow path cross-sectional area of ​​the straight pipe. In the piping system 1A, the straight pipe 32 of the vertical pipe 3A is disposed downstream of the bent pipe 5-1 that changes the direction of the flow path, and the straight pipe 42 of the horizontal pipe 4A is disposed downstream of the bent pipe 5-2 that changes the direction of the flow path. The protruding member 6A-1 is a first protruding member that is disposed so that at least a part of the vertical pipe 3A is a straight pipe. In this embodiment, at least a part of the vertical pipe 3A is a straight pipe 32. The protruding member 6A-2 is a second protruding member that is disposed so that at least a part of the horizontal pipe 4A is a straight pipe. In this embodiment, at least a part of the horizontal pipe 4A is a straight pipe 42.

[0089] The protruding members 6A-1 and 6A-2, together with the straight pipes 32 and 42 in which the protruding members 6A-1 and 6A-2 are arranged, form the piping members 10A-1 and 10A-2, respectively. In this embodiment, the piping member 10A-1 including the protruding member 6A-1 and the straight pipe 32 is the first piping member. In this embodiment, the piping member 10A-2 including the protruding member 6A-2 and the straight pipe 42 is the second piping member. In this embodiment, the piping member 10A-1 is composed of a part (straight pipe 32) of the vertical pipe 3A, unlike the piping member 10-1 that uses the entire vertical pipe 3, and is therefore easier to transport than the piping member 10-1.

[0090] The protrusion members 6A-1 and 6A-2 have the same configuration. Therefore, the piping members 10A-1 and 10A-2 have substantially the same configuration, although there is a difference between the straight pipe 32 of the vertical pipe 3A and the straight pipe 42 of the horizontal pipe 4A. The following mainly describes the piping member 10A-1 in detail. Those skilled in the art can easily understand that the description of the piping member 10A-1 is a description of the piping member 10A-2 by replacing the description related to the vertical pipe 3A with the description related to the horizontal pipe 4A.

[0091] Fig. 16 is a perspective view of a configuration example of the piping member 10A-1, and Fig. 17 is an exploded perspective view of the piping member 10A-1. As can be seen from Fig. 16 and Fig. 17, the piping member 10A-1 includes a straight pipe 32 of a vertical pipe 3A and a protruding member 6A-1.

[0092] 17, the protruding member 6A-1 has a size, that is, a length, a width, and a height (thickness), that allows it to be placed inside the straight pipe 32 of the upright pipe 3A. The material of the protruding member 6A-1 is, for example, hard polyvinyl chloride.

[0093] The protruding member 6A-1 has a first end 6a and a second end 6b. The first end 6a and the second end 6b are both ends in the longitudinal direction of the protruding member 6A-1. The longitudinal direction of the protruding member 6A-1 coincides with the direction of the central axis C3 of the vertical pipe 3A. The first end 6a faces the upstream side, and the second end 6b faces the downstream side. In the protruding member 6A-1, a fluid flow is generated from the first end 6a to the second end 6b.

[0094] Fig. 18 is a cross-sectional view of the piping member 10A-1. Fig. 19 is a cross-sectional view taken along line BB in Fig. 18. Fig. 20 is a cross-sectional view of a portion of the piping member 10A-1. Fig. 21 is a plan view of the piping member 10A-1. Fig. 22 is a bottom view of the piping member 10A-1.

[0095] As can be seen from Figs. 18 to 22, the protruding member 6A-1 has the same shape as the protruding member 6-1 on the first end 6a side. On the other hand, unlike the protruding member 6-1, the protruding member 6A-1 has an end face 68 on the second end 6b. The end face 68 intersects with the central axis C3 of the vertical pipe 3A. In this embodiment, the end face 68 is perpendicular to the central axis C3 of the vertical pipe 3A.

[0096] As shown in FIG. 18, the protruding member 6A-1 is contained within the straight pipe 32 in the direction of the central axis C3 of the vertical pipe 3A. In this embodiment, the length of the protruding member 6A-1 (the distance between the first end 6a and the second end 6b) is equal to the length of the straight pipe 32. That is, in the piping member 10A-1, the entire protruding member 6A-1 is within the straight pipe 32. This makes it possible to protect the protruding member 6A-1 by the straight pipe 32, compared to a case in which the protruding member 6A-1 is partially protruding from the straight pipe 32. This reduces the possibility of damage to the protruding member 6A-1.

[0097] FIG. 23 is a comparison diagram between the protruding member 6A-1 according to the second embodiment and the protruding member 6-1 according to the first embodiment. From FIG. 23, it can be said that the protruding member 6A-1 has a shape in which the portion of the protruding member 6-1 on the second end 6b side is cut in a direction perpendicular to the central axis C3 of the vertical pipe 3A. The height of the protruding member 6A-1 decreases monotonically from the top 6c toward the second end 6b. If the length of the protruding member 6A-1 is extended downstream, the protruding member 6A-1 virtually has a portion where the height of the protruding member 6A-1 becomes 0. The portion where the height of the protruding member 6A-1 becomes 0 may correspond to the second end 6b of the protruding member 6-1.

[0098] The protruding member 6A-1 can be made smaller in size in the direction of the central axis C3 of the vertical pipe 3A than the protruding member 6-1. In particular, the protruding member 6A-1 has a shape in which the portion of the protruding member 6-1 on the second end 6b side protruding from the straight pipe 32 to the outside is cut. In other words, when the protruding member 6-1 is arranged in the straight pipe 32, the portion of the protruding member 6-1 on the second end 6b side protrudes outward from the second end of the straight pipe 32. The second end 6b of the protruding member 6-1 is thin and therefore easily damaged. Therefore, when the protruding member 6-1 is arranged in the straight pipe 32, there is a possibility that the protruding member 6-1 may be damaged during transportation or the like. In contrast, the protruding member 6A-1 is entirely inside the straight pipe 32, so the possibility of damage to the protruding member 6A-1 can be reduced.

[0099] The protruding member 6A-1 has an advantage that the dimension in the direction of the central axis C3 of the upright pipe 3A can be made smaller than that of the protruding member 6-1, and damage can be prevented. Such a change in shape between the protruding member 6A-1 and the protruding member 6-1 can also cause a change in pressure loss. Therefore, the change in pressure loss caused by the difference in shape between the protruding member 6-1 and the protruding member 6A-1 was evaluated. Figure 24 is a graph showing the change in pressure loss caused by the protruding member 6A-1 relative to the protruding member 6-1.

[0100] In the graph of Fig. 24, the vertical axis indicates pressure loss in the piping member. The horizontal axis indicates length percentage [%]. The length percentage [%] is the percentage of the distance from the apex 6c to the second end 6b of the protruding member 6A-1 to the distance from the apex 6c to the second end 6b of the protruding member 6-1.

[0101] In Fig. 18 and Fig. 23, the distance between the first end 6a and the second end 6b of the protruding member 6A-1 in the direction of the central axis C3 of the vertical pipe 3A is represented by L'. The distance between the top 6c and the second end 6b of the protruding member 6A-1 in the direction of the central axis C3 of the vertical pipe 3A is represented by L2'. In Fig. 23, the distance between the second end 6b of the protruding member 6A-1 and the second end 6b of the protruding member 6-1 in the direction of the central axis C3 of the vertical pipe 3A is represented by ΔL. L2 = L2' + ΔL, and L = L' + ΔL. The length percentage [%] is calculated by L2' / L2 × 100.

[0102] In FIG. 24, a length ratio of 100% indicates that the shape of the protruding member 6A-1 is equal to the shape of the protruding member 6-1. A length ratio of 0% indicates that the shape of the protruding member 6A-1 is from the first end 6a to the apex 6c. The height of the protruding member 6A-1 decreases monotonically from the apex 6c to the second end 6b. Therefore, the height of the protruding member 6A-1 at the second end 6b increases as the length ratio decreases. From FIG. 24, it can be seen that the effect of reducing pressure loss decreases as the length ratio decreases. However, the relationship between the length ratio and the pressure loss is not linear, and the pressure loss increases exponentially with respect to the decrease in the length ratio. In other words, the increase in pressure loss with respect to the decrease in the length ratio is relatively gradual. In other words, it can be said that the decrease in the effect of reducing pressure loss with respect to the decrease in the length ratio is limited. In consideration of these points, L2' is set to satisfy the following condition. That is, if the height of the protruding member 6A-1 at the top 6c is H1 and the height of the protruding member 6A-1 at the second end 6b is H2, then 0.05H1≦H2≦0.90H1. This allows for miniaturization while improving the flow rate. In particular, the length of the protruding member 6A-1 can be made shorter than that of the protruding member 6-1. This allows for miniaturization of the protruding member 6A-1. Furthermore, the protruding member 6A-1 has fewer thin portions downstream of the protruding member 6A-1 compared to the protruding member 6-1, which may reduce the possibility of damage to the protruding member 6A-1.

[0103] As described in the first embodiment, it is preferable that 0.5d≦L≦5.0d is satisfied for the protruding member 6-1. This can further reduce the occurrence of pressure loss caused by separation downstream from the bent pipe 5-1. Therefore, the flow rate can be improved while enabling miniaturization. Here, as described above, L=L1+L2'+ΔL. If the reduction amount per unit length of the height of the protruding member 6-1 from the top 6c to the second end 6b is constant, then (H1-H2) / L2'=H2 / ΔL. That is, ΔL=H2 / (H1-H2)×L2'. Therefore, the formula 0.5d≦L≦5.0d can be rewritten as 0.5d≦L1+H1 / (H1-H2)×L2'≦5.0d using L1 and L2'. Therefore, in the protrusion member 6A-1, if the inner diameter of the straight pipe 32 is d, the distance between the first end 6a and the top 6c in the direction of the central axis C3 of the straight pipe 32 is L1, and the distance between the top 6c and the second end 6b in the direction of the central axis C3 of the straight pipe 32 is L2', then it is preferable that 0.5d≦L1+H1 / (H1-H2)×L2'≦5.0d.

[0104] [1.2.2 Effects, etc.] The above-described protruding members 6A-1 and 6A-2 are provided with a top portion 6c between the first end 6a and the second end 6b, which minimizes the flow path cross-sectional area of ​​the straight pipes 32 and 42. The protruding members 6A-1 and 6A-2 have an end face 68 at the second end 6b, which intersects with the central axes C3 and C4 of the straight pipes 32 and 42. If the height at the top portion 6c is H1 and the height at the second end 6b is H2, then 0.05H1≦H2≦0.90H1 is satisfied. This configuration can improve the flow rate while enabling miniaturization.

[0105] In the protruding members 6A-1 and 6A-2, if the inner diameter of the straight pipes 32 and 42 is d, the distance between the first end 6a and the apex 6c in the direction of the central axis C3 and C4 of the straight pipes 32 and 42 is L1, and the distance between the apex 6c and the second end 6b in the direction of the central axis C3 and C4 of the straight pipes 32 and 42 is L2', then 0.5d≦L1+H1 / (H1-H2)×L2'≦5.0d. This configuration can improve the flow rate while enabling miniaturization.

[0106] [2. Modifications] The embodiments of the present disclosure are not limited to the above-mentioned embodiments. The above-mentioned embodiments can be modified in various ways depending on the design, etc., as long as the object of the present disclosure can be achieved. Below, modified examples of the above-mentioned embodiments are listed. The modified examples described below can be applied in appropriate combination.

[0107] In the following, reference will be made to symbols used in the first embodiment even though they are applicable to either the first or second embodiment described above. However, this is merely for the purpose of simplifying the description and is not intended to exclude application to the second embodiment.

[0108] In one modified example, the first side surface 62 and the second side surface 63 of the protrusion member 6-1 may have an asymmetric shape with respect to the center line of the protrusion member 6-1 along the central axis C3 of the vertical pipe 3. Depending on the installation environment of the piping system 1 or the piping member 10, the shapes of the first side surface 62 and the second side surface 63 may be set individually, and do not necessarily have to be symmetric with respect to the center line of the protrusion member 6-1 along the central axis C3 of the vertical pipe 3.

[0109] In one modification, the protruding member 6-1 does not necessarily have to have the contact end surface 66.

[0110] In one modified example, the shape, number and arrangement of the protrusions 67 of the protrusion member 6-1 may be appropriately changed according to the shape, number and arrangement of the recesses 3c of the upright pipe 3. The recesses 3c may be holes rather than notches. The position of the recesses 3c is not limited to the edge of the upstream end 3. The protrusions 67 and the recesses 3c are preferably provided so as to facilitate positioning of the protrusion member 6-1 relative to the upright pipe 3. However, the protrusion member 6-1 does not necessarily have to have the protrusions 67.

[0111] In one modified example, the protruding member 6-1 may be formed integrally with the riser pipe 3, rather than being a separate member from the riser pipe 3. This is equivalent to the inner peripheral surface 30a of the riser pipe 3 including the main surface 61 and the first and second side surfaces 62, 63 of the protruding member 6-1.

[0112] In one modified example, the protruding members 6-1 and 6-2 do not necessarily have to have the same configuration or structure. For example, at least one of the protruding members 6-1 and 6-2 may satisfy one or more of 0.1L≦L1≦0.5L, A1 / A≦0.4, or 0.5d≦L≦5.0d.

[0113] In one modified example, the protruding members 6-1 and 6-2 do not necessarily have to have the same shape and size, and may have different shapes and sizes. In other words, the shapes and sizes of the protruding members 6-1 and 6-2 may be appropriately set depending on the locations where the protruding members 6-1 and 6-2 are arranged.

[0114] In one variant, the protruding member 6-1 does not have to be entirely contained within the riser pipe 3. In particular, the second end 6b of the protruding member 6-1 may protrude from the riser pipe 3 to the outside.

[0115] In one modified example, the material of the protruding member 6-1 does not necessarily have to be hard polyvinyl chloride. The material of the protruding member 6-1 may be determined according to the requirements of the piping system 1, and may be, for example, a synthetic resin such as polyethylene. Also, the material of the protruding member 6-1 may be a metal instead of a synthetic resin.

[0116] In one modified example, the shape and size of a part or the whole of the piping system 1 may be different from those of the above embodiment. For example, unlike the above embodiment, in the piping system 1, the shape of the bent pipes 5-1 and 5-2, the shape of the vertical pipe 3, and the shape of the horizontal pipe 4 may be polygonal rather than circular.

[0117] In one modified example, the bent pipes 5-1 and 5-2 are not limited to 90° bent elbows (so-called DL) defined in JIS K 6739. The bent pipes 5-1 and 5-2 may be 90° large bent elbows (so-called LL) or 45° elbows (so-called 45L) defined in JIS K 6739. The dimensions of the bent pipes 5-1 and 5-2 do not necessarily need to be set in accordance with the standard of JIS K 6739 "Rigid polyvinyl chloride pipe joints for drainage."

[0118] In one modified example, the piping system 1 does not necessarily have to include the eaves gutter 2. For example, if the building 11 has a structure with a water collection port such as a balcony, the bent pipe 5-2 of the piping system 1 may be connected to the water collection port of the building 11.

[0119] In one modification, the piping system 1 may include only one of the protruding members 6-1 and 6-2. Thus, the piping system 1 includes a vertical pipe 3 fixed to a wall surface 11b of the building 11, a horizontal pipe 4 between the vertical pipe 3 and a water collection port 2b for rainwater from the building 11, a first bent pipe 5-1 between the horizontal pipe 4 and the vertical pipe 3, a second bent pipe 5-2 between the water collection port 2b and the horizontal pipe 4, and one or more protruding members 6-1 and 6-2, and the one or more protruding members 6-1 and 6-2 may be arranged such that at least a portion of the horizontal pipe 4 or the vertical pipe 3 is a straight pipe.

[0120] In one modified example, the drain 8 may be a drain having a structure that is generally considered not to contribute to the occurrence or promotion of the siphoning phenomenon. In one modified example, the piping system 1 does not necessarily have to include the drain 8. The drain 8 is not an essential component of the piping system 1, and may be provided as appropriate taking into consideration the installation environment of the piping system 1, etc.

[0121] In one modified example, the piping system 1 does not necessarily have to include the upright pipe 7. The upright pipe 7 is not an essential component of the piping system 1, and may be provided appropriately in consideration of the installation environment of the piping system 1, etc.

[0122] In one modified example, the piping system 1 is not limited to a gutter system, which is a type of drainage system, but may be other drainage systems such as a sewage system, or may be applied to a water supply system such as a drinking water system. In other words, the protrusion member or the piping member can be used in a system that supplies water or drains water.

[0123] [3. Aspects] As is apparent from the above embodiment and modifications, the present disclosure includes the following aspects.

[0124] [Aspect 1] A protrusion member that is disposed in a straight pipe downstream of a bent pipe that changes the direction of a flow path and partially reduces a flow path cross-sectional area of ​​the straight pipe, a main surface extending from a first end facing the upstream side to a second end facing the downstream side and facing the center side of the straight pipe when viewed from the direction of the central axis of the straight pipe; A first side surface and a second side surface on both sides of the main surface when viewed from the direction of the central axis of the straight pipe; a first separation wall disposed between the main surface and the first side surface to promote separation of a flow along the main surface and a flow along the first side surface; a second separation wall disposed between the main surface and the second side surface to promote separation of a flow along the main surface and a flow along the second side surface; Equipped with Protruding member.

[0125] [Aspect 2] When viewed from the direction of the central axis of the straight pipe, at least a part of the main surface is concave. The protrusion member of embodiment 1.

[0126] [Aspect 3] When viewed from the direction of the central axis of the straight pipe, the radius of curvature of at least a part of the main surface is equal to or smaller than the radius of curvature of the inner peripheral surface of the straight pipe. The protruding member of embodiment 2.

[0127] [Aspect 4] The shape of the main surface as viewed along the central axis of the straight pipe changes from a concave shape to a convex shape from the first end to the second end. The protruding member of embodiment 2 or 3.

[0128] [Aspect 5] a top portion between the first end and the second end that minimizes the flow cross-sectional area of ​​the straight pipe; The shape of the main surface as viewed from the direction of the central axis of the straight pipe is a convex shape at the top. The protruding member of embodiment 4.

[0129] [Aspect 6] a top portion between the first end and the second end that minimizes the flow cross-sectional area of ​​the straight pipe; The main surface narrows from the first end to the second end, at least from the first end to the apex. The protrusion member according to any one of embodiments 1 to 5.

[0130] [Aspect 7] When viewed from the direction of the central axis of the straight pipe, at least a portion of the first side surface and the second side surface are concave. The protrusion member according to any one of embodiments 1 to 6.

[0131] [Aspect 8] a top portion between the first end and the second end that minimizes the flow path cross-sectional area of ​​the straight pipe; The first side surface and the second side surface have a concave shape whose depth becomes shallower from the top portion toward the second end. The protruding member of embodiment 7.

[0132] [Aspect 9] The first side surface and the second side surface are symmetrical with respect to a center line of the protruding member along the central axis of the straight pipe. The protrusion member according to any one of the first to eighth embodiments.

[0133] [Aspect 10] The first side surface and the second side surface are asymmetric with respect to a center line of the protruding member along the central axis of the straight pipe. The protrusion member according to any one of the first to eighth embodiments.

[0134] [Aspect 11] The first side surface and the second side surface have a width that increases from the first end toward the second end. The protrusion member according to any one of the first to tenth embodiments.

[0135] [Aspect 12] a top portion between the first end and the second end that minimizes the flow path cross-sectional area of ​​the straight pipe; The distance between the first end and the second end in the direction of the central axis of the straight pipe is L. If the distance between the first end and the top in the direction of the central axis of the straight pipe is L1, 0.1L≦L1≦0.5L; The protrusion member according to any one of the first to eleventh embodiments.

[0136] [Aspect 13] a top portion between the first end and the second end that minimizes the flow cross-sectional area of ​​the straight pipe; The maximum flow area of ​​a straight pipe is A. If the cross-sectional area of ​​the protruding member at the top is A1, A1 / A≦0.4; The protrusion member according to any one of the first to second embodiments.

[0137] [Aspect 14] The inner diameter of the straight pipe is d. If the distance between the first end and the second end in the direction of the central axis of the straight pipe is L, 0.5d≦L≦5.0d; The protrusion member according to any one of the first to thirteenth embodiments.

[0138] [Aspect 15] a top portion between the first end and the second end that minimizes the flow cross-sectional area of ​​the straight pipe; The second end has an end surface that intersects with the central axis of the straight pipe; If the height at the top is H1 and the height at the second end is H2, then 0.05H1≦H2≦0.90H1. The protrusion member according to any one of the first to eleventh embodiments.

[0139] [Aspect 16] The inner diameter of the straight pipe is d. The distance between the first end and the top in the direction of the central axis of the straight pipe is L1. If the distance between the top and the second end in the direction of the central axis of the straight pipe is L2', 0.5d≦L1+H1 / (H1-H2)×L2'≦5.0d; The protrusion member of embodiment 15.

[0140] [Aspect 17] A protrusion member according to any one of aspects 1 to 16, Straight pipe and Equipped with Piping components.

[0141] [Aspect 18] A vertical pipe fixed to the wall of a building; A horizontal pipe between the rainwater collection outlet from the building and the vertical pipe, a first bent pipe between the horizontal pipe and the vertical pipe; a second bent pipe between the collection port and the horizontal pipe; One or more protruding members according to any one of aspects 1 to 16; Equipped with One or more protruding members are arranged such that at least a portion of the horizontal pipe or vertical pipe is a straight pipe; Piping system.

[0142] Aspects 2 to 16 are optional and not essential. [Industrial Applicability]

[0143] The present disclosure is applicable to a protrusion member, a piping member, and a piping system. Specifically, the present disclosure is applicable to a protrusion member for changing a flow path cross-sectional area, a piping member including a protrusion member, and a piping system including a piping member. [Explanation of symbols]

[0144] 1,1A Piping System 2b Water collection port 3,3A vertical pipe (straight pipe) 32 straight pipe 4,4A horizontal pipe (straight pipe) 42 straight pipe 5-1 Bend pipe (first bend pipe) 5-2 Bend pipe (second bend pipe) 6-1, 6-2, 6A-1, 6A-2 Protruding parts 6a 1st end 6b 2nd end 6c top 61 Main surface 62 First aspect 63 Second aspect 64 1st separation wall 65 Second separation wall 68 End face 10-1, 10-2, 10A-1, 10A-2 Piping components C3,C4 center axis F1 Flow along the main surface F2 Flow along the first side F3 Flow along the second side

Claims

1. a protrusion member disposed in a straight pipe disposed downstream of a bent pipe that changes the direction of a flow path, the protrusion member partially reducing a flow path cross-sectional area of ​​the straight pipe, a main surface extending from a first end facing the upstream side to a second end facing the downstream side and facing the center of the straight pipe when viewed from the direction of the central axis of the straight pipe; a top portion between the first end and the second end, which minimizes the flow path cross-sectional area of ​​the straight pipe; Equipped with The second end has an end surface that intersects with the central axis of the straight pipe, When the height at the top is H1 and the height at the second end is H2, 0.05H1≦H2≦0.90H1. Protruding member.

2. The inner diameter of the straight pipe is d, The distance between the first end and the top in the direction of the central axis of the straight pipe is L1, If the distance between the top and the second end in the direction of the central axis of the straight pipe is L2', 0.5d≦L1+H1 / (H1−H2)×L2′≦5.0d, The protruding member according to claim 1 .

3. When viewed from the direction of the central axis of the straight pipe, at least a part of the main surface has a concave shape. The protruding member according to claim 1 .

4. When viewed from the direction of the central axis of the straight pipe, the radius of curvature of at least a part of the main surface is equal to or less than the radius of curvature of the inner circumferential surface of the straight pipe. The protruding member according to claim 3 .

5. a shape of the main surface, as viewed from a direction of a central axis of the straight pipe, changes from a concave shape to a convex shape from the first end toward the second end; The protruding member according to claim 3 .

6. The shape of the main surface as viewed from the direction of the central axis of the straight pipe is a convex shape at the top. The protruding member according to claim 5 .

7. the main surface narrows in width from the first end to the second end at least from the first end to the apex; The protruding member according to claim 1 .

8. The distance between the first end and the second end in the direction of the central axis of the straight pipe is L, If the distance between the first end and the top in the direction of the central axis of the straight pipe is L1, 0.1L≦L1≦0.5L, The protruding member according to claim 1 .

9. The maximum flow path cross-sectional area of ​​the straight pipe is A, If the cross-sectional area of ​​the protruding member at the top is A1, A1 / A≦0.4; The protruding member according to claim 1 .

10. The inner diameter of the straight pipe is d, When the distance between the first end and the second end in the direction of the central axis of the straight pipe is L, 0.5d≦L≦5.0d; The protruding member according to claim 1 .

11. The protruding member according to claim 1 ; The straight pipe; Equipped with Piping components.

12. A vertical pipe fixed to the wall of the building; a horizontal pipe located between a rainwater collection outlet from the building and the vertical pipe; a first bent pipe located between the horizontal pipe and the vertical pipe; a second bent pipe located between the water collection port and the horizontal pipe; One or more protruding members according to claim 1; Equipped with The one or more protruding members are arranged such that at least a portion of the horizontal pipe or the vertical pipe is the straight pipe. Piping system.