Piping system

Abstract

To provide a piping system capable of enhancing a flow rate while enabling miniaturization.SOLUTION: A piping system 1 forming a flow path comprises: a horizontal pipe 4; a vertical pipe 3; an elbow 52 having a first receiving port 522 into which an end of the horizontal pipe 4 is inserted, a second receiving port 521 into which an end of the vertical pipe 3 is inserted, and a corner portion 520c on an inner circumferential side between the first receiving port 522 and the second receiving port 521; and protrusion members 6J-1, 6J-3 arranged on the inner circumferential side of the elbow 52 at an end 4b of the horizontal pipe 4 or an end 3a of the vertical pipe 3 so as to partially reduce a flow cross-sectional area of the flow path. The protrusion members 6J-1, 6J-3 have a first end 6a and a second end 6b in a length direction. The first end 6a is arranged toward the corner portion 520c of the elbow 52, and distances D4, D5 between the first end 6a and the corner portion 520c are 0 mm or more and 20 mm or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to piping systems. [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 has a cylindrical section penetrating a water collection port formed on the bottom surface of the eaves gutter and that 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 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 periphery side is greater than 64 mm and less than 100 mm. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-120068 Summary of the Invention [Problem to be solved by the invention]

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

[0005] The present disclosure provides a piping system that allows for increased flow rate while enabling compactness. [Means for solving the problem]

[0006] A piping system according to one embodiment of the present disclosure is a piping system that forms a flow path, and includes a horizontal pipe, a vertical pipe, a first receiving port into which the end of the horizontal pipe is inserted, a second receiving port into which the end of the vertical pipe is inserted, an elbow having a corner on the inner circumference between the first receiving port and the second receiving port, and a protrusion member that is arranged on the inner circumference of the elbow at the end of the horizontal pipe or the end of the vertical pipe so as to partially reduce the flow path cross-sectional area of ​​the flow path, wherein the protrusion member has first and second ends in the length direction, the first end is arranged toward the corner of the elbow, and the distance between the first end and the corner is between 0 mm and 20 mm. Another aspect of the piping system is a piping system that forms a flow path, and includes a horizontal pipe, a vertical pipe, an elbow having a first receiving port for inserting the end of the horizontal pipe and a second receiving port for inserting the end of the vertical pipe, and a protrusion member that is arranged on the inner side of the elbow at the end of the horizontal pipe or the end of the vertical pipe so as to partially reduce the flow path cross-sectional area of ​​the flow path, and the rotation angle of the protrusion member around the central axis of the horizontal pipe or the vertical pipe on which the protrusion member is arranged is greater than or equal to 0 degrees and less than 10 degrees with respect to a reference attitude. [Effects of the Invention]

[0007] Aspects of the present disclosure can improve flow rates while allowing for compactness. [Brief explanation of the drawings]

[0008] [Figure 1] Schematic diagram of a piping system according to a first embodiment [Figure 2] FIG. 1 is an exploded cross-sectional view of a portion including a first elbow of a piping system according to a first embodiment; [Figure 3] FIG. 1 is an exploded cross-sectional view of a portion including a second elbow of the piping system according to the first embodiment; [Figure 4] 1 is a cross-sectional view of a portion including a first elbow of a piping system according to a first embodiment; [Figure 5] 1 is a cross-sectional view of a portion including a second elbow of a piping system according to a first embodiment; [Figure 6] Cross section of line AA in Figure 2 [Figure 7] FIG. 1 is a perspective view of a protrusion member and a first straight pipe portion according to a first embodiment; [Figure 8] 1 is a side view of a protrusion member and a first straight pipe portion according to a first embodiment; [Figure 9] FIG. 1 is a plan view of a protrusion member and a first straight pipe portion according to a first embodiment; [Figure 10] 1 is a bottom view of a protrusion member and a first straight pipe portion according to the first embodiment; [Figure 11] Cross section of line BB in Figure 9 [Figure 12] A perspective cross-sectional view taken along line CC in Figure 9. [Figure 13] Cross section of line DD in Figure 11 [Figure 14] 1 is a diagram of a simulation of pressure distribution in a piping system of a comparative example. [Figure 15] Schematic diagram of a piping system according to a second embodiment [Figure 16] Schematic diagram of a piping system according to a third embodiment [Figure 17] Schematic diagram of a piping system according to a fourth embodiment [Figure 18] Schematic diagram of a piping system according to a fifth embodiment [Figure 19] Schematic diagram of a piping system according to a sixth embodiment [Figure 20] Schematic diagram of a piping system according to a seventh embodiment [Figure 21] Schematic diagram of a piping system according to an eighth embodiment [Figure 22] FIG. 13 is an exploded perspective view of a downstream portion of a second elbow of a piping system according to a ninth embodiment. [Figure 23] 13 is a cross-sectional view of a downstream portion of a second elbow of a piping system according to a ninth embodiment. [Figure 24] Cross section of line AA in Figure 23 [Figure 25] 13 is a cross-sectional view of a part of a downspout of a piping system according to a ninth embodiment. [Figure 26] 13 is a plan view of a protrusion member and a downspout according to a ninth embodiment. [Figure 27] 13 is a bottom view of the protrusion member and the downspout according to the ninth embodiment. [Figure 28] Cross section of line IX-IX in Figure 24 [Figure 29] Cross section of line XX in Figure 24 [Figure 30] Cross section of line XI-XI in Figure 24 [Figure 31] Cross section of Figure 24 along line XII-XII [Figure 32] Cross section of line XIII-XIII in Figure 24 [Figure 33] FIG. 23 is a longitudinal cross-sectional view showing a peripheral structure of a corner portion of a second elbow of a piping system according to a tenth embodiment. [Figure 34] FIG. 23 is a plan view showing a protruding member disposed on a vertical pipe of a piping system according to an eleventh embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] [1. Embodiment] Hereinafter, embodiments of the present disclosure will be described, occasionally with reference to the drawings. However, the following embodiments are merely examples for explaining the present disclosure, and are not intended to limit the present disclosure to the following content (e.g., the shape, dimensions, and arrangement of each component). Positional relationships, such as up, down, left, and right, are based on the positional relationships shown in the drawings, unless otherwise specified. Each figure described in the following embodiments is a schematic diagram, and the ratios of the size and thickness of each component in each figure do not necessarily reflect the actual dimensional ratios. Furthermore, the dimensional ratios of each element are not limited to the ratios shown in the drawings.

[0010] 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 each other by the symbols attached to them, the prefixes such as "first" and "second" may be omitted in consideration of readability of the text.

[0011] In the following description, when it is necessary to distinguish between multiple components, suffixes such as "-1" and "-2" are added to the symbols of the components. However, when it is not necessary to distinguish between multiple components, the suffixes "-1" and "-2" may be omitted to improve readability.

[0012] 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 to transport a fluid with a Reynolds number of 4000 or greater. A fluid with a Reynolds number of 4000 or greater is considered to be a fluid whose flow within a cylinder becomes turbulent. Examples of such fluids include liquids (drinking water, heat source water, wastewater, oil, etc.), gases (air, steam, etc.), and gas-liquid two-phase flow (a mixture of liquid and gas). In this embodiment, the piping system 1 is used as a drainage system. The piping system 1 is a gutter system that receives rainwater from the roof 10a of a building 10 and channels it to a manhole 21 on the ground 20. The piping system 1 forms a rainwater flow path. The rainwater collected in the manhole 21 flows from the manhole 21 through an underground pipe 22 and into a storm sewer. The building 10 may be, for example, a non-residential facility such as a store, office, factory, building, school, welfare facility, or hospital, or a residential facility such as a detached house, an apartment building, or each dwelling unit of a detached house or apartment building. Non-residential facilities also include theaters, movie theaters, public halls, amusement parks, complexes, department stores, hotels, inns, kindergartens, libraries, museums, art galleries, underground shopping malls, stations, and airports.

[0013] The piping system 1 includes an eaves gutter 2, a vertical pipe 3, a horizontal pipe 4, a first elbow 51, a second elbow 52, ​​protruding members 6-1, 6-2, 6-3, and 6-4, a vertical pipe 7, and a drain 8.

[0014] The eaves gutter 2 collects rainwater from the roof 10a of the building 10. The eaves gutter 2 is installed under the roof 10a of the building 10. As an example, the eaves gutter 2 is arranged at the eaves edge of the roof 10a. In particular, the eaves gutter 2 is arranged so as to extend along the eaves edge of the roof 10a. The eaves gutter 2 is shaped like a long bucket. The eaves gutter 2 has a bottom wall 2a. An inlet 2b is formed in the bottom wall 2a depending on the overall design of the piping system 1. The inlet 2b is, for example, a circular opening. In a rain gutter system, the inlet 2b is also referred to as a water collection inlet, a drain outlet, or a drop outlet. 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 to reinforce the overall strength of the eaves gutter 2. The core material may be made of, for example, metal. As another example, the eaves gutter 2 may be formed from a metal plate, for example, a steel plate (also called a coil).

[0015] The drain 8 is disposed at the inlet 2b of the eaves gutter 2. The drain 8 reduces the generation of vortices and air entrainment at the inlet 2b. The drain 8 may contribute to the generation of siphoning. The drain 8 may have a known configuration.

[0016] In the piping system 1, the upright pipe 3 is not directly connected to the inlet 2b, but is connected to the inlet 2b via the horizontal pipe 4, the upright pipe 7, the first elbow 51, and the second elbow 52.

[0017] 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 inlet 2b. The standpipe 3 allows rainwater from the inlet 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). 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 inlet 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 pipe cover 30 is arranged to prevent rainwater from flowing into the manhole 21 through a gap between the upright pipe 3 and the manhole 21.

[0018] FIG. 2 is a cross-sectional view of a portion of the piping system 1 including the second elbow 52, ​​and FIG. 3 is an exploded cross-sectional view of the portion of the piping system 1 including the second elbow 52.

[0019] In this embodiment, the vertical pipe 3 is made up of a plurality of piping members. The vertical pipe 3 includes a first straight pipe portion 31 and a second straight pipe portion 32.

[0020] The first straight pipe section 31 is an upstream portion of the standpipe 3. The first straight pipe section 31 has a main body section 311 and a socket 312. The main body section 311 has a straight pipe shape. As shown in FIGS. 2 and 3, the main body section 311 has openings 311a and 311b at a first end (upper end in FIG. 3) and a second end (lower end in FIG. 3), respectively. In the standpipe 3, the first end of the first straight pipe section 31 defines the upstream end section 3a of the standpipe 3. The socket 312 is provided at the second end of the main body section 311. The socket 312 is provided to connect the second straight pipe section 32 to the first straight pipe section 31. The socket 312 is cylindrical and surrounds the opening 311b of the main body section 311.

[0021] The second straight pipe section 32 is connected to the downstream side of the first straight pipe section 31. The second straight pipe section 32 is the downstream part of the vertical pipe 3. The second straight pipe section 32 has a straight pipe shape. A first end (upper end in Figures 1 and 3) of the second straight pipe section 32 is connected to the socket 312 of the first straight pipe section 31. A second end (lower end in Figure 1) of the second straight pipe section 32 defines the downstream end 3b of the vertical pipe 3.

[0022] In the vertical pipe 3, the main body 311 of the first straight pipe portion 31 and the second straight pipe portion 32 have the same inner diameter. The inner diameters of the main body 311 of the first straight pipe portion 31 and the second straight pipe portion 32 define the flow path cross-sectional area of ​​the vertical pipe 3.

[0023] The horizontal pipe 4 defines a flow path that intersects the vertical direction. In a gutter system, the horizontal pipe 4 is also called a call gutter. The horizontal pipe 4 is a part that allows rainwater from the building 10 to flow from the inlet 2b to the standpipe 3. The horizontal pipe 4 is located between the inlet 2b for rainwater from the building 10 and the standpipe 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 relative 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 of the horizontal pipe 4 that is connected to the inlet 2b (the left end in Figure 1). The downstream end 4b is the end of the horizontal pipe 4 that is connected to the standpipe 3 (the right end in Figure 1).

[0024] FIG. 4 is a cross-sectional view of a portion of the piping system 1 including the first elbow 51, and FIG. 5 is an exploded cross-sectional view of the portion of the piping system 1 including the first elbow 51.

[0025] In this embodiment, the horizontal pipe 4 is made up of a plurality of piping members. The horizontal pipe 4 includes a first straight pipe section 41, a second straight pipe section 42, and a third straight pipe section 43.

[0026] The first straight pipe section 41 is an upstream portion of the horizontal pipe 4. As shown in FIGS. 4 and 5 , the first straight pipe section 41 has a main body section 411 and a socket 412. The main body section 411 is straight. The main body section 411 has openings 411a and 411b at a first end (the left end in FIG. 5 ) and a second end (the right end in FIG. 5 ), respectively. In the horizontal pipe 4, the first end of the first straight pipe section 41 defines the upstream end 4a of the horizontal pipe 4. The socket 412 is provided at the second end of the main body section 411. The socket 412 is provided to connect the third straight pipe section 43 to the first straight pipe section 41. The socket 412 is cylindrical and surrounds the opening 411b of the main body section 411.

[0027] The second straight pipe section 42 is a downstream portion of the horizontal pipe 4. As shown in FIGS. 2 and 3, the second straight pipe section 42 has a main body section 421 and a socket 422. The main body section 421 is straight. The main body section 421 has openings 421a and 421b at a first end (the right end in FIG. 3) and a second end (the left end in FIG. 3), respectively. In the horizontal pipe 4, the first end of the second straight pipe section 42 defines the downstream end 4b of the horizontal pipe 4. The socket 422 is provided at the second end of the main body section 421. The socket 422 is provided to connect the third straight pipe section 43 to the second straight pipe section 42. The socket 422 is cylindrical and surrounds the opening 421b of the main body section 421.

[0028] The third straight pipe section 43 is connected between the first straight pipe section 41 and the second straight pipe section 42. The third straight pipe section 43 has a straight pipe shape. As shown in FIGS. 4 and 5, a first end (the left end in FIGS. 4 and 5) of the third straight pipe section 43 is connected to the socket 412 of the first straight pipe section 41. As shown in FIGS. 2 and 3, a second end (the right end in FIGS. 2 and 3) of the third straight pipe section 43 is connected to the socket 422 of the second straight pipe section 42.

[0029] In the horizontal pipe 4, the inner diameters of the main body 411 of the first straight pipe section 41, the main body 421 of the second straight pipe section 42, and the third straight pipe section 43 are equal to one another. The inner diameters of the main body 411 of the first straight pipe section 41, the main body 421 of the second straight pipe section 42, and the third straight pipe section 43 define the flow path cross-sectional area of ​​the horizontal pipe 4.

[0030] The standpipe 7 defines a vertical flow path. Rainwater flows vertically through the standpipe 7 from the inlet 2b. The standpipe 7 is connected to the drain 8 and is located downstream of the inlet 2b. The standpipe 7 is located between the inlet 2b and the horizontal pipe 4. The standpipe 7 is straight. The cross section perpendicular to the central axis C7 of the standpipe 7 is circular. The standpipe 7 is located so that the direction of the central axis C7 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 inlet 2b (the upper end in FIG. 1). The downstream end 7b is the end of the standpipe 7 that is connected to the horizontal pipe 4 (the lower end in FIG. 1).

[0031] As shown in FIGS. 4 and 5, the standpipe 7 has a main body 711 and a socket 712. The main body 711 is straight. The main body 711 has openings 711a and 711b at a first end (the lower end in FIGS. 4 and 5) and a second end (the upper end in FIGS. 4 and 5), respectively. In the standpipe 7, the first end of the main body 711 defines the downstream end 7b of the standpipe 7. The socket 712 is provided at the second end of the main body 711. The socket 712 is provided for connection to the inlet 2b. The socket 712 is cylindrical and surrounds the opening 711b of the main body 711.

[0032] As an example, the material of the standpipe 3, horizontal pipe 4, and standpipe 7 is rigid polyvinyl chloride. The dimensions of the standpipe 3, horizontal pipe 4, and standpipe 7, such as 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."

[0033] The first elbow 51 and the second elbow 52 change the direction of the flow path. The first elbow 51 and the second elbow 52 are joints that connect flow paths with different directions, such as a vertical pipe and a horizontal pipe.

[0034] 4 and 5, the first elbow 51 has a curved pipe portion (bent portion) 510 and sockets 511, 512. The curved pipe portion 510 and the sockets 511, 512 are formed as a continuous, integrated unit.

[0035] The curved pipe portion 510 has openings 511a, 512a at both ends. The curved pipe portion 510 is cylindrical, but the pipe axis (center line) of the curved pipe portion 510 is curved rather than straight. The angle between the center lines C511, C512 of the openings 511a, 512a at both ends of the first elbow 51 in a cross section taken along a plane including the pipe axis of the first elbow 51 is 91.17°, as specified in JIS K 6739 "Rigid polyvinyl chloride pipe fittings for drainage," for example.

[0036] In a cross section of the first elbow 51 taken on a plane including the pipe axis, the curved pipe portion 510 has an inner surface 510a on the inner circumferential side and an inner surface 510b on the outer circumferential side. The inner surface 510a has a corner 510c. The corner 510c is located in the middle part of the inner surface 510a between the openings 511a and 512a. The corner 510c has an R-shape. In a cross section of the first elbow 51 taken on a plane including the pipe axis, the corner 510c has a radius of curvature of 0 to 2 mm. The inner surface 510b does not have a corner like the corner 510c. The inner surface 510b is curved overall.

[0037] The sockets 511 and 512 are provided at both ends of the curved pipe portion 510. The sockets 511 and 512 are provided to connect piping members to the first elbow 51. In this embodiment, the socket 511 is connected to the upstream end 4a of the horizontal pipe 4, and the socket 512 is connected to the drain 8 via the standpipe 7. The sockets 511 and 512 are cylindrical and surround the openings 511a and 512a of the curved pipe portion 510, respectively.

[0038] 2 and 3, the second elbow 52 has a curved pipe portion (bent portion) 520 and sockets 521 and 522. The curved pipe portion 520 and the sockets 521 and 522 are formed as a continuous, integrated unit.

[0039] The curved pipe portion 520 has openings 521a, 522a at both ends. In a cross section taken along a plane including the pipe axis of the first elbow 51, the curved pipe portion 510 has an inner surface 510a on the inner circumferential side and an inner surface 510b on the outer circumferential side. The inner surface 510a has a corner 510c. The curved pipe portion 520 has the same configuration as the curved pipe portion 510, so a description thereof will be omitted.

[0040] The sockets 521 and 522 are provided at both ends of the curved pipe portion 520. The sockets 521 and 522 are provided to connect piping members to the second elbow 52. In this embodiment, the socket 521 is connected to the upstream end 3a of the standpipe 3, and the socket 522 is connected to the downstream end 4b of the horizontal pipe 4. The sockets 521 and 522 are cylindrical and surround the openings 521a and 522a of the curved pipe portion 520, respectively.

[0041] The material of the first elbow 51 and the second elbow 52 may be rigid polyvinyl chloride. The dimensions of the first elbow 51 and the second elbow may be set in accordance with, for example, the standard JIS K 6739 "Rigid polyvinyl chloride pipe fittings for drainage."

[0042] The piping system 1 includes a first elbow 51 and a second elbow 52. The direction of the flow path changes in each of the first elbow 51 and the second elbow 52. When the direction of the flow path changes, pressure loss due to separation can be one factor in a decrease in flow rate. In order to reduce the decrease in flow rate due to pressure loss caused by the first elbow 51 or the second elbow 52, ​​protrusion members 6-1 to 6-4 are provided.

[0043] 1, 2, and 3, the protruding member 6-1 is located on the inner circumferential side of the second elbow 52 at the upstream end 3a of the standpipe 3, and partially reduces the flow path cross-sectional area of ​​the flow path of the piping system 1. More specifically, the protruding member 6-1 is located in the first straight pipe section 31 of the standpipe 3. The protruding member 6-1 is provided in the first straight pipe section 31 so as to protrude from a first wall surface 31b on the inner circumferential side of the second elbow 52 in the first straight pipe section 31 to a second wall surface 31c on the outer circumferential side of the second elbow 52 in the first straight pipe section 31. Here, the first wall surface 31b is a portion of the inner circumferential surface 31a of the first straight pipe section 31 on the inner circumferential side of the second elbow 52 (for example, half of the portion on the inner circumferential side). The second wall surface 31c is a portion of the inner circumferential surface 31a of the first straight pipe section 31 on the outer circumferential side of the second elbow 52 (for example, a half portion on the outer circumferential side). The inner circumferential surface 31a of the first straight pipe section 31 is composed of the first wall surface 31b and the second wall surface 31c. In this embodiment, the protrusion member 6-1 is formed integrally with the first straight pipe section 31.

[0044] As shown in FIGS. 1, 4, and 5, the protruding member 6-2 is located on the inner circumferential side of the first elbow 51 at the upstream end 4a of the horizontal pipe 4 and partially reduces the flow path cross-sectional area of ​​the flow path of the piping system 1. More specifically, the protruding member 6-2 is located on the first straight pipe section 41 of the horizontal pipe 4. The protruding member 6-2 is provided on the first straight pipe section 41 so as to protrude from a first wall surface 41b on the inner circumferential side of the first elbow 51 in the first straight pipe section 41 to a second wall surface 41c on the outer circumferential side of the first elbow 51 in the first straight pipe section 41. Here, the first wall surface 41b is a portion of the inner circumferential surface 41a of the first straight pipe section 41 on the inner circumferential side of the first elbow 51 (for example, half of the inner circumferential side). The second wall surface 41c is a portion of the inner circumferential surface 41a of the first straight pipe section 41 on the outer circumferential side of the first elbow 51 (for example, half of the outer circumferential side). An inner peripheral surface 41a of the first straight pipe portion 41 is made up of a first wall surface 41b and a second wall surface 41c. In this embodiment, the protruding member 6-2 is formed integrally with the first straight pipe portion 41.

[0045] As shown in FIGS. 1, 2, and 3, the protruding member 6-3 is located on the inner circumferential side of the second elbow 52 at the downstream end 4b of the horizontal pipe 4 and partially reduces the flow path cross-sectional area of ​​the flow path of the piping system 1. More specifically, the protruding member 6-3 is located on the second straight pipe section 42 of the horizontal pipe 4. The protruding member 6-3 is provided on the second straight pipe section 42 so as to protrude from a first wall surface 42b on the inner circumferential side of the second elbow 52 in the second straight pipe section 42 to a second wall surface 42c on the outer circumferential side of the second elbow 52 in the second straight pipe section 42. Here, the first wall surface 42b is a portion of the inner circumferential surface 42a of the second straight pipe section 42 on the inner circumferential side of the second elbow 52 (for example, half of the inner circumferential side). The second wall surface 42c is a portion of the inner circumferential surface 42a of the second straight pipe section 42 on the outer circumferential side of the second elbow 52 (for example, half of the outer circumferential side). The inner circumferential surface 42a of the second straight pipe portion 42 is made up of a first wall surface 42b and a second wall surface 42c. In this embodiment, the protruding member 6-3 is formed integrally with the second straight pipe portion 42.

[0046] As shown in FIGS. 1, 4, and 5, the protruding member 6-4 is located on the inner circumferential side of the first elbow 51 between the inlet 2b and the first elbow 51, and partially reduces the flow path cross-sectional area of ​​the flow path of the piping system 1. More specifically, the protruding member 6-4 is located on the standpipe 7. The protruding member 6-4 is provided on the standpipe 7 so as to protrude from a first wall surface 71b on the inner circumferential side of the first elbow 51 of the standpipe 7 to a second wall surface 71c on the outer circumferential side of the first elbow 51 of the standpipe 7. Here, the first wall surface 71b is a portion on the inner circumferential side of the first elbow 51 on the inner circumferential surface 71a of the standpipe 7 (for example, half of the portion on the inner circumferential side). The second wall surface 71c is a portion on the inner circumferential surface 71a of the standpipe 7 on the outer circumferential side of the first elbow 51 (for example, half of the portion on the outer circumferential side). The inner peripheral surface 71a of the standpipe is composed of a first wall surface 71b and a second wall surface 71c. In this embodiment, the protruding member 6-4 is formed integrally with the standpipe .

[0047] The protrusion members 6-1 to 6-4 have the same configuration, although they are arranged in different locations. The following mainly describes in detail the protrusion member 6-1 and the first straight pipe portion 31 of the standpipe 3. Those skilled in the art can easily understand that the description of the protrusion member 6-1 and the first straight pipe portion 31 of the standpipe 3 is a description of the protrusion members 6-2 to 6-4 by replacing the description related to the first straight pipe portion 31 with the description related to the first straight pipe portion 41 for the protrusion member 6-2, the description related to the first straight pipe portion 31 with the description related to the second straight pipe portion 42 for the protrusion member 6-3, and the description related to the first straight pipe portion 31 with the description related to the standpipe 7 for the protrusion member 6-4. In the following description, the protrusion member 6-1 may be simply referred to as the protrusion member 6 for ease of reading.

[0048] Fig. 6 is a cross-sectional view taken along line AA in Fig. 5. Figs. 7 to 13 show the protrusion member 6 and the first straight pipe portion 31. Fig. 7 is a perspective view of the protrusion member 6 and the first straight pipe portion 31. Fig. 8 is a side view of the protrusion member 6 and the first straight pipe portion 31. Fig. 9 is a plan view of the protrusion member 6 and the first straight pipe portion 31. Fig. 10 is a bottom view of the protrusion member 6 and the first straight pipe portion 31. Fig. 11 is a cross-sectional view taken along line BB in Fig. 9. Fig. 12 is a perspective cross-sectional view taken along line CC in Fig. 9. Fig. 13 is a cross-sectional view taken along line DD in Fig. 11.

[0049] As shown in FIGS. 2, 6, and 11, the protrusion member 6 has a first end 6a and a second end 6b. The first end 6a and the second end 6b are both ends of the protrusion member 6 in the longitudinal direction. The longitudinal direction of the protrusion member 6 corresponds to the flow direction of the fluid in the standpipe 3. The flow direction of the fluid in the standpipe 3 coincides with the direction of the central axis C3 of the standpipe 3. The first end 6a is closer to the second elbow 52 than the second end 6b. In this embodiment, the first end 6a is the upstream end, and the second end 6b is the downstream end.

[0050] In a plane passing through the central axes C521, C522 of the openings 521a, 522a of the second elbow 52, ​​the surface of the protrusion member 6 has a curved shape that protrudes from the first wall surface 31b toward the second wall surface 31c. The height of the protrusion member 6 varies along the direction of the central axis C3 of the standpipe 3. In this embodiment, the protrusion member 6 has a top portion 6c between the first end 6a and the second end 6b. The top portion 6c is the highest part of the protrusion member 6. The height of the protrusion member 6 increases monotonically from the first end 6a toward the top portion 6c. The height of the protrusion member 6 decreases monotonically from the top portion 6c toward the second end 6b. The protrusion member 6 minimizes the flow path cross-sectional area of ​​the standpipe 3 at the top portion 6c.

[0051] 9, 10 and 13. When viewed from the direction of the central axis C3 of the standpipe 3, the protruding member 6 has a shape in which the center is recessed more than the both sides, thereby improving the flow rate.

[0052] From another perspective, it is sufficient that the protruding member 6 has a shape that protrudes from the inner periphery toward the outer periphery of the second elbow 52 so as to produce the Coanda effect in the straight pipe section (first straight pipe section 31) on the downstream side of the second elbow 52. In other words, it is sufficient that the protruding member 6 has a shape that produces the Coanda effect in the straight pipe section (first straight pipe section 31) on the downstream side of the second elbow 52. This makes it possible to improve the flow rate while making the device more compact.

[0053] In this way, by providing the protruding member 6 on the first straight pipe section 31 of the standpipe 3, a reduced region P where the flow path cross-sectional area of ​​the piping system 1 is smaller than the flow path cross-sectional area of ​​the standpipe 3 exists downstream of the second elbow 52 between the corner 520c on the inner periphery side of the second elbow 52 and the opening 311b of the first straight pipe section 31. The reduced region P is the region of the standpipe 3 where the protruding member 6 exists.

[0054] As shown in FIGS. 7 and 8 , the first end 6 a of the protruding member 6 protrudes to the outside from the opening 311 a of the first straight pipe section 31. Therefore, when the second elbow 52 and the first straight pipe section 31 are connected, as shown in FIG. 2 , the first end 6 a of the protruding member 6 protrudes from the opening 521 a into the curved pipe section 520 of the second elbow 52 and covers a part of the inner surface 520 a of the curved pipe section 520. In this embodiment, the first end 6 a of the protruding member 6 coincides with the corner 520 c of the inner surface 520 a of the curved pipe section 520. In other words, the distance between the first end 6 a and the corner 520 c is zero. In this way, because the protruding member 6 is present across the curved pipe section 520 of the second elbow 52 and the first straight pipe section 31, the influence of a step that may occur at the boundary between the curved pipe section 520 of the second elbow 52 and the first straight pipe section 31 can be reduced.

[0055] As shown in FIGS. 7 to 9 , the first straight pipe section 31 further has markings 313. The markings 313 indicate information regarding the assembly of the first straight pipe section 31. In this embodiment, the markings 313 indicate the direction in which the first straight pipe section 31 is connected to the second elbow 52. The markings 313 in FIG. 7 are arrows indicating the direction in which the first straight pipe section 31 is connected to the second elbow 52. In FIGS. 7 to 9 , four markings 313 are arranged at equal intervals in the circumferential direction on the outer peripheral surface of the upstream end of the first straight pipe section 31. The markings 313 may be letters, figures, symbols, three-dimensional shapes, colors, or combinations thereof that are recognizable by human perception. In this embodiment, the markings 313 are located on the outer peripheral surface of the first straight pipe section 31 so as not to be hidden by the socket 521 of the second elbow 52 when the first straight pipe section 31 is connected to the second elbow 52. However, the mark 313 may be located at a position on the outer circumferential surface of the first straight pipe section 31 that is hidden by the socket 521 of the second elbow 52 when the first straight pipe section 31 is connected to the second elbow 52 .

[0056] As described above, by providing the protrusion member 6 to the first straight pipe section 31, a reduced area P where the flow path cross-sectional area of ​​the vertical pipe 3 is smaller than that of the opening 311b exists between the corner 520c of the second elbow 52 and the opening 311b.

[0057] Next, the function of the protruding member 6 will be described.

[0058] FIG. 14 is a diagram illustrating a simulation of pressure distribution when water flows through a piping system 100 of a comparative example. The piping system 100 of the comparative example differs from the piping system 1 in that it does not have a protruding member 6. In FIG. 14, darker colors indicate lower pressure. In particular, pressure loss is large at the portion indicated by R in FIG. 14, and the presence of such a portion with high pressure loss can be a major factor in reducing the flow rate. The pressure loss at the portion indicated by R in FIG. 14 is thought to be caused by separation. This separation occurs when water separates from the first wall surface 31b of the standpipe 3 downstream of the corner 520c of the second elbow 52. That is, as indicated by arrow F in FIG. 14, water flowing in from the upstream side initially flows along the pipe wall 200, but after the corner 520c of the second elbow 52, ​​it may separate from the first wall surface 31b of the standpipe 3. This separation is particularly noticeable when the water flow velocity is high. The faster the flow velocity, the wider the area where pressure loss occurs.

[0059] In the piping system 1, the flow path direction changes significantly at the second elbow 52, ​​and pressure loss due to separation can contribute to a decrease in flow rate. The protruding member 6-1 is located at the end of the standpipe 3 on the second elbow 52 side (upstream end 3a). In particular, the protruding member 6-1 is located on the inner circumferential side of the standpipe 3 (left side in FIG. 1 ) of the second elbow 52. In the protruding member 6-1, the apex 6c is closer to the first end 6a than the second end 6b, and the first end 6a is closer to the second elbow 52 than the second end 6b. In the protruding member 6, a fluid flow occurs from the first end 6a to the second end 6b. The presence of the protruding member 6-1 is expected to (1) make it easier for the fluid to flow along the pipe wall than in the absence of the protruding member 6-1, and (2) reduce the number of areas where pressure loss may occur. Therefore, the protruding member 6-1 can reduce pressure loss due to separation downstream from the second elbow 52, ​​thereby improving the flow rate. Unlike the technology described in Patent Document 1, the piping system 1 can be made smaller simply by including the protruding member 6-1, since it is not necessary to increase the radius of curvature of the inner peripheral surface of the inner peripheral side of the second elbow 52. Therefore, the protruding member 6-1 can improve the flow rate while enabling a smaller size. The protruding member 6-1 is located inside the standpipe 3, and is therefore inconspicuous 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.

[0060] In the piping system 1, the direction of water flow also changes significantly at the first elbow 51, and pressure loss due to separation can contribute to a decrease in flow rate. The protruding member 6-2 is located at the end of the horizontal pipe 4 on the first elbow 51 side (the upstream end 4a). In particular, the protruding member 6-2 is located on the inner circumferential side of the first elbow 51 (the upper side in FIG. 1 ) of the horizontal pipe 4. In the protruding member 6-2, the apex 6c is closer to the first end 6a than the second end 6b, and the first end 6a is closer to the first elbow 51 than the second end 6b. In the protruding member 6-2, a fluid flow occurs from the first end 6a to the second end 6b. The presence of the protruding member 6-2 is expected to (1) facilitate fluid flow along the pipe wall more easily than in the absence of the protruding member 6-2, and (2) reduce the number of areas where pressure loss may occur. Therefore, the protruding member 6-2 can reduce pressure loss due to separation downstream from the first elbow 51, thereby improving flow rate. Unlike the technology described in Patent Document 1, the piping system 1 can be made smaller simply by including the protruding member 6-2, since it is not necessary to increase the radius of curvature of the inner peripheral surface of the inner peripheral side of the first elbow 51. Therefore, the protruding member 6-2 can improve the flow rate while enabling a smaller size. The protruding member 6-2 is located inside the horizontal pipe 4, and is therefore less 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.

[0061] In the piping system 1, there is an area downstream of the second elbow 52 where pressure loss due to separation is likely to occur. The protruding member 6-3 is located at the end of the horizontal pipe 4 on the second elbow 52 side (downstream end 4b). In particular, the protruding member 6-3 is located on the inner circumferential side of the horizontal pipe 4 (the lower side in FIG. 1 ) of the second elbow 52. In the protruding member 6-3, the apex 6c is closer to the first end 6a than the second end 6b, and the first end 6a is closer to the second elbow 52 than the second end 6b. In the protruding member 6-3, a fluid flow occurs from the second end 6b to the first end 6a. The presence of the protruding member 6-3 can guide the fluid to the area downstream of the second elbow 52 where pressure loss due to separation is likely to occur. This is expected to reduce the number of areas where pressure loss may occur. Therefore, the protruding member 6-3 can reduce pressure loss due to separation downstream of the second elbow 52 and improve flow rate. Unlike the technology described in Patent Document 1, the piping system 1 can be made smaller simply by including the protruding member 6-3, since it is not necessary to increase the radius of curvature of the inner peripheral surface of the inner peripheral side of the second elbow 52. Therefore, the protruding member 6-3 can improve the flow rate while enabling a smaller size. The protruding member 6-3 is located inside the horizontal pipe 4, and is therefore less 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.

[0062] In the piping system 1, there is an area downstream of the first elbow 51 where pressure loss due to separation is likely to occur. The protruding member 6-4 is located at the end of the riser pipe 7 on the first elbow 51 side (downstream end 7b). In particular, the protruding member 6-4 is located on the inner circumferential side of the riser pipe 7 (right side in FIG. 1 ) of the first elbow 51. In the protruding member 6-4, the apex 6c is closer to the first end 6a than the second end 6b, and the first end 6a is closer to the first elbow 51 than the second end 6b. In the protruding member 6-4, a fluid flow occurs from the second end 6b to the first end 6a. The presence of the protruding member 6-4 can guide the fluid to the area downstream of the first elbow 51 where pressure loss due to separation is likely to occur. This is expected to reduce the number of areas where pressure loss may occur. Therefore, the protruding member 6-4 can reduce pressure loss due to separation downstream of the first elbow 51 and improve the flow rate. Unlike the technology described in Patent Document 1, the piping system 1 can be made smaller simply by including the protruding member 6-4, since it is not necessary to increase the radius of curvature of the inner peripheral surface of the inner peripheral side of the first elbow 51. Therefore, the protruding member 6-4 can improve the flow rate while enabling a smaller size. The protruding member 6-4 is located inside the standpipe 7, and is therefore less 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.

[0063] As described above, in the piping system 1, the first and second elbows 51, 52 can cause pressure loss within the pipeline. When the first and second elbows 51, 52 are present within the pipeline, the first and second elbows 51, 52 are essentially equivalent within the pipeline. The first and second elbows 51, 52 generally have a loss coefficient of approximately 0.3 to 1.5, depending on their shapes. Here, by arranging the protruding members 6 on either the upstream or downstream side of one of the first and second elbows 51, 52, the influence of pressure loss due to one of the first and second elbows 51, 52 can be reduced. In particular, by arranging the protruding members 6 on both the upstream and downstream sides of one of the first and second elbows 51, 52, the fluid flows along the protruding members 6 from the upstream side to the downstream side of one of the first and second elbows 51, 52. This allows the fluid to flow smoothly through the curved flow path within one of the first and second elbows 51, 52, which further reduces pressure loss. Therefore, by arranging the protrusion members 6 on both the upstream and downstream sides of both the first and second elbows 51, 52, as in the piping system 1, the pressure loss in each of the first and second elbows 51, 52 can be significantly reduced, and the effect of reducing pressure loss can be maximized.

[0064] Next, an example of the dimensions of the piping system 1 will be described.

[0065] 2 and 6, the diameter of the riser pipe 3 is d, and the length of the protruding member 6 in the direction of the central axis C3 of the riser pipe 3 is L. In the piping system 1, it is preferable that 0.5d≦L≦5.0d. This can further reduce the pressure loss caused by the second elbow 52. Therefore, the flow rate can be improved while enabling miniaturization.

[0066] 2 and 6, the apex 6c of the protruding member 6 is the portion of the reduced portion P where the cross-sectional area of ​​the flow path is smallest. The distance between the corner 520c of the second elbow 52 and the apex 6c in the direction of the central axis C3 of the standpipe 3 is defined as D1. In the piping system 1, it is preferable that 0≦D1≦0.5d. This can further reduce the occurrence of pressure loss caused by the second elbow 52. Therefore, the flow rate can be improved while enabling miniaturization.

[0067] In FIG. 6, the distance between the top 6c and the downstream end (second end 6b) in the direction of the central axis C3 of the vertical pipe 3 is defined as D3. D3=L-D1. In the piping system 1, it is preferable that D3>D1. This can further reduce the pressure loss caused by the second elbow 52. Therefore, the flow rate can be improved while enabling miniaturization.

[0068] 9 and 11 , the distance between the top 6c and the second wall surface 31c in a plane passing through the central axes C521, C522 of the sockets 521, 522 of the second elbow 52 is defined as D2. In the piping system 1, it is preferable that 0.60d≦D2≦0.95d. This can further reduce pressure loss caused by the second elbow 52. Therefore, it is possible to improve the flow rate while enabling miniaturization. Here, the height of the protruding member 6 at the top 6c is defined as H. H is expressed as H=d−D2. In the piping system 1, it is preferable that 0.05d≦H≦0.40d. This can further reduce pressure loss caused by the second elbow 52. Therefore, it is possible to improve the flow rate while enabling miniaturization.

[0069] Referring to FIG. 13, the maximum value of the flow path cross-sectional area of ​​the standpipe 3 (maximum flow path cross-sectional area) is A, and the minimum value of the flow path cross-sectional area of ​​the standpipe 3 (minimum flow path cross-sectional area) is A1. The minimum value of the flow path cross-sectional area of ​​the standpipe 3 is the flow path cross-sectional area at the top 6c of the protruding member 6. In the piping system 1, it is preferable that (A-A1) / A≦0.5. Preferably, it is preferable that (A-A1) / A≦0.4. This can further reduce the pressure loss caused by the second elbow 52. Therefore, it is possible to improve the flow rate while enabling miniaturization. Here, the maximum value of the cross-sectional area of ​​the protruding member 6 is A2. A2 is also the cross-sectional area of ​​the protruding member 6 at the top 6c of the protruding member 6. A2=A-A1. That is, in the piping system 1, it is preferable that A2 / A≦0.5, and preferably A1 / A≦0.4.

[0070] In the piping system 1, if the horizontal pipe 4 is too long, the effect of a decrease in flow velocity in the horizontal pipe 4 becomes significant. Therefore, the length of the horizontal pipe 4 is preferably 2.0 m or less. This can reduce the decrease in flow velocity in the horizontal pipe 4 and improve the flow rate.

[0071] In the piping system 1, the height at which the siphoning effect is effective refers to the height at which the piping is not divided, there is no portion completely open to the outside air, and the siphoning effect is maintained. The height at which the siphoning effect is effective is expressed as the vertical distance between the upstream opening point and the downstream opening point of the piping system 1. The upstream opening point of the piping system 1 is the portion upstream of the piping system that is open to the outside air. The downstream opening point of the piping system 1 is the portion downstream of the piping system 1 that is open to the outside air. There is no portion completely open to the outside air between the upstream opening point and the downstream opening point of the piping system 1. In other words, the downstream opening point is the point that is open to atmospheric pressure and where the siphoning effect stops. Therefore, the upstream opening point and the downstream opening point can be said to be the upstream and downstream ends of the range at which the siphoning effect is maintained in the piping system 1. It is believed that the greater the difference in potential energy between the upstream opening point and the downstream opening point of the piping system 1, the greater the flow rate due to the improved flow velocity caused by the siphoning effect. In the piping system 1, the vertical pipe 3 includes a first straight pipe section 31 and a second straight pipe section 32, and the first straight pipe section 31 and the second straight pipe section 32 have the same inner diameter. The length of the vertical pipe 3 is 2.0 m or more. Therefore, the length of the portion of the vertical pipe 3 with the same inner diameter is equal to the entire length of the vertical pipe 3. In this case, the length of the portion of the vertical pipe 3 with the same inner diameter is 2.0 m or more. This allows the height at which the siphon effect is effective to be 2.0 m or more. This improves the flow rate.

[0072] In the piping system 1, if the inner diameter of the flow path of the piping system 1 is too large, it becomes difficult for the piping system 1 to be filled with fluid. In order to efficiently induce the siphon effect, it is preferable that the piping system 1 be easily filled with fluid. Therefore, in this embodiment, the inner diameter of the flow path of the piping system 1 is 160 mm or less throughout the flow path. In particular, in the piping system 1, the inner diameters of the piping components that make up the piping system 1, mainly the upright pipe 3, horizontal pipe 4, and upright pipe 7, are 160 mm or less.

[0073] [1.1.2 Effects, etc.] The piping system 1 described above is a piping system that forms a flow path and includes a vertical pipe 3, a horizontal pipe 4 between the inlet 2b and the vertical pipe 3, a first elbow 51 between the inlet 2b and the horizontal pipe 4, a second elbow 52 between the horizontal pipe 4 and the vertical pipe 3, and one or more protrusion members 6-1 to 6-4 that are located on at least one of the inner circumferential side of the first elbow 51 between the inlet 2b and the first elbow 51, the inner circumferential side of the first elbow 51 at the upstream end 4a of the horizontal pipe 4, the inner circumferential side of the second elbow 52 at the downstream end 4b of the horizontal pipe 4, and the inner circumferential side of the second elbow 52 at the upstream end 3a of the vertical pipe 3, and that partially reduce the flow path cross-sectional area of ​​the flow path. The horizontal pipe 4 has a length of 2.0 m or less. The length of the portion of the vertical pipe 3 with the same inner diameter is 2.0 m or more. The inner diameter of the flow path is 160 mm or less throughout the flow path. This configuration allows for increased flow rate while still allowing for compactness.

[0074] In the piping system 1, one or more protruding members 6-1 to 6-4 have a top portion 6c that is located between a first end 6a and a second end 6b in the flow direction of the fluid through the flow path and that minimizes the cross-sectional area of ​​the flow path. This configuration can improve the flow rate while enabling miniaturization.

[0075] In the piping system 1, the first elbow 51 and the second elbow 52 are 90° elbows. Compared to a 45° elbow, this configuration allows the distance between the inlet 2b and the standpipe 3 in the horizontal direction to be longer even when the horizontal pipe 4 is short.

[0076] 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 a tee 110, a second upright pipe 111, a second eaves gutter 112, a third elbow 113, a second horizontal pipe 114, and a second drain 115 in addition to an eaves gutter 2, a vertical pipe 3, a horizontal pipe 4, a first elbow 51, a second elbow 52, ​​protruding members 6-1, 6-2, 6-3, and 6-4, a vertical pipe 7, and a drain 8.

[0077] The tee 110 has a first receiving port 110a facing upward, a second receiving port 110b facing downward, and a third receiving port 110c facing sideways. The tee 110 merges the fluid flowing in from the first receiving port 110a with the fluid flowing in from the third receiving port 110c, and discharges the combined fluid from the second receiving port 110b. The angle between the central axis of the first receiving port 110a and the central axis of the third receiving port 110c is 90° or less. As an example, the angle between the central axis of the first receiving port 110a and the central axis of the third receiving port 110c is set to 88.83°. As an example, the material of the tee 110 is hard polyvinyl chloride.

[0078] The first socket 110a is connected to the downstream end 3b of the standpipe 3. The second socket 110b is connected to the second standpipe 111. The third socket 110c is connected to the second eaves gutter 112 via the third elbow 113 and the second horizontal pipe 114.

[0079] The second standpipe 111 is installed to drain water from the standpipe 3 into the manhole 21. In this embodiment, the second standpipe 111 has the same pipe diameter as the standpipe 3. For example, the second standpipe 111 is the same size as the standpipe 3. The second standpipe 111 is straight. The cross section perpendicular to the central axis of the second standpipe 111 is circular. The second standpipe 111 is arranged so that the direction of the central axis of the second standpipe 111 coincides with the up-down direction (vertical direction). The second standpipe 111 has an upstream end 111a and a downstream end 111b. The upstream end 111a is connected to the second receiving port 110b of the tee 110. The downstream end 111b is inserted into the manhole 21. A piping cover 30 is arranged to prevent rainwater from flowing into the manhole portion 21 through a gap between the second upright pipe 111 and the manhole portion 21.

[0080] The second eaves gutter 112 collects rainwater from roofs or eaves below the roof 10a of the building 10. For example, the second eaves gutter 112 is installed below the eaves gutter 2. The second eaves gutter 112 is shaped like a long bucket. The second eaves gutter 112 has a bottom wall 112a. A second inlet 112b different from the inlet 2b is formed in the bottom wall 112a according to the overall design of the piping system 1. The second inlet 112b is, for example, a circular opening. As an example, the second eaves gutter 112 may be formed by extrusion molding of a resin material. The second eaves gutter 112 may include a core material to reinforce the overall strength of the second eaves gutter 112. The core material may be made of, for example, metal. As another example, the second eaves gutter 112 may be formed from a metal plate, for example, a steel plate (also called a coil).

[0081] The second drain 115 is disposed at the second inlet 112b of the second eaves gutter 112. The second drain 115 does not necessarily have to have a configuration that can contribute to the occurrence of the siphoning phenomenon. The second drain 115 may have a well-known configuration.

[0082] The third elbow 113 changes the direction of the flow path. The third elbow 113 is a connecting joint that connects flow paths with different directions. The third elbow 113 has a curved pipe portion 1130 and sockets 1131 and 1132 at both ends of the curved pipe portion 1130. In the third elbow 113, the socket 1132 is connected to the second drain 115, and thereby to the second inlet 112b. The socket 1131 is connected to the second standpipe 111. As an example, the material of the third elbow 113 may be rigid polyvinyl chloride. The dimensions of the third elbow 113 may be set in accordance with the standard JIS K 6739, "Rigid polyvinyl chloride pipe fittings for drainage."

[0083] The second horizontal pipe 114 is installed to drain water from the second eaves gutter 112 to the manhole section 21. In this embodiment, the second horizontal pipe 114 is a straight pipe. The cross section perpendicular to the central axis of the second horizontal pipe 114 is circular. The second horizontal pipe 114 is arranged so that the direction of the central axis of the second horizontal pipe 114 intersects the up-down direction (vertical direction). The second horizontal pipe 114 has an upstream end 114a and a downstream end 114b. The upstream end 114a is connected to the socket 1131 of the third elbow 113. The downstream end 114b is connected to the third socket 110c of the tee 110.

[0084] As an example, the material of the second upright pipe 111 and the second horizontal pipe 114 is rigid polyvinyl chloride. The dimensions of the second upright pipe 111 and the second horizontal pipe 114, such as 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."

[0085] In the piping system 1A described above, the vertical distance L11 between the second elbow 52 and the tee 110 is 2.0 m or more. This allows the fluid from the second inlet 112b to merge with the fluid from the inlet 2b, while improving the flow rate.

[0086] [1.2.2 Effects, etc.] The piping system 1A described above further includes a tee 110 having a first receiving port 110a facing upward, a second receiving port 110b facing downward, and a third receiving port 110c facing sideways. The first receiving port 110a is connected to the downstream end 3b of the standpipe 3. The third receiving port 110c is connected to a second inlet 112b different from the inlet 2b. The vertical distance between the second elbow 52 and the tee 110 is 2.0 m or more. This configuration can improve the flow rate while allowing the fluid from the second inlet 112b to merge with the fluid from the inlet 2b.

[0087] 1.3 Third Embodiment 1.3.1 Configuration 16 is a schematic diagram of a piping system 1B according to embodiment 3. The piping system 1B includes a piping 12 in addition to an eaves gutter 2, a vertical pipe 3, a horizontal pipe 4, a first elbow 51, a second elbow 52, ​​protruding members 6-1, 6-2, 6-3, and 6-4, a vertical pipe 7, and a drain 8.

[0088] The pipe 12 has a larger diameter than the standpipe 3. For example, the pipe 12 is one size or more larger than the standpipe 3. The pipe 12 is installed to drain water from the standpipe 3 to the manhole 21. The pipe 12 is also called a curing pipe.

[0089] The pipe 12 has a straight pipe shape. The cross section perpendicular to the central axis of the pipe 12 is circular. The pipe 12 is arranged so that the direction of the central axis of the pipe 12 coincides with the up-down direction (vertical direction). The pipe 12 has an upstream end 12a and a downstream end 12b. The downstream end 3b of the standpipe 3 is inserted into the upstream end 12a. The downstream end 12b is inserted into the manhole 21. In Figure 16, a pipe cover 30 is arranged to prevent rainwater from flowing into the manhole 21 through the gap between the pipe 12 and the manhole 21.

[0090] As an example, the material of the pipe 12 is rigid polyvinyl chloride. The dimensions of the pipe 12, such as 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."

[0091] In the piping system 1B, the length L12 of the portion of the riser pipe 3 inserted into the pipe 12 is 1.0 m or more. This makes it possible to stabilize the flow of fluid from the riser pipe 3 to the pipe 12.

[0092] [1.3.2 Effects, etc.] In the piping system 1B described above, the downstream end 3b of the riser pipe 3 is inserted into the pipe 12, which has a larger diameter than the riser pipe 3. The length of the portion of the riser pipe 3 inserted into the pipe 12 is 1.0 m or more. This configuration stabilizes the flow of fluid from the riser pipe 3 to the pipe 12.

[0093] 1.4 Fourth embodiment 1.4.1 Configuration 17 is a schematic diagram of a piping system 1C according to embodiment 4. The piping system 1C includes an increaser 130 and a second standpipe 131 in addition to an eaves gutter 2, a standpipe 3, a horizontal pipe 4, a first elbow 51, a second elbow 52, ​​protruding members 6-1, 6-2, 6-3, and 6-4, a standpipe 7, and a drain 8.

[0094] The increaser 130 has a first socket 130a facing upward and a second socket 130b facing downward. The second socket 130b is larger than the first socket 130a. The inner diameter of the increaser 130 increases from the first socket 130a toward the second socket 130b. In this embodiment, the central axes of the first socket 130a and the second socket 130b are aligned.

[0095] The first socket 130a is connected to the downstream end 3b of the standpipe 3. The second socket 130b is connected to the second standpipe 131.

[0096] As an example, the material of the increaser 130 is rigid polyvinyl chloride. The dimensions of the increaser 130 may be set in accordance with the standard of JIS K 6739 "Rigid polyvinyl chloride pipe joints for drainage," for example.

[0097] The second standpipe 131 has a larger pipe diameter than the standpipe 3. For example, the second standpipe 131 is one size or more larger than the standpipe 3. The second standpipe 131 is installed to drain water from the standpipe 3 to the inlet section 21.

[0098] The second standpipe 131 has a straight pipe shape. A cross section perpendicular to the central axis of the second standpipe 131 is circular. The second standpipe 131 is arranged so that the direction of the central axis of the second standpipe 131 coincides with the up-down direction (vertical direction). The second standpipe 131 has an upstream end 131a and a downstream end 131b. The upstream end 131a is connected to the second receiving port 130b of the increaser 130. The downstream end 131b is inserted into the manhole 21. A piping cover 30 is arranged to prevent rainwater from flowing into the manhole 21 through a gap between the second standpipe 131 and the manhole 21.

[0099] As an example, the material of the second standpipe 131 is rigid polyvinyl chloride. The dimensions of the second standpipe 131, such as 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."

[0100] In the piping system 1C, the distance L13 between the second elbow 52 and the increaser 130 in the vertical direction is 2.0 m or more. This allows the flow of fluid from the upright pipe 3 to the second upright pipe 131 to be stabilized.

[0101] [1.4.2 Effects, etc.] The piping system 1C described above further includes an increaser 130 having an upward-facing first receiver 130a and a downward-facing second receiver 130b with a larger inner diameter than the first receiver 130a. The first receiver 130a is connected to the downstream end 3b of the standpipe 3. The vertical distance between the second elbow 52 and the increaser 130 is 2.0 m or more. This configuration stabilizes the flow of fluid from the standpipe 3 to the second standpipe 131.

[0102] 1.5 Fifth embodiment 1.5.1 Configuration FIG. 18 is a schematic diagram of a piping system 1D according to a fifth embodiment. The piping system 1D is used to sprinkle water from an eaves gutter 2 onto a second roof 10c below a roof 10a. As an example, the roof 10a may be a main roof, and the second roof 10c may be a eaves. In FIG. 18, the second roof 10c is a folded-plate roof.

[0103] The piping system 1D includes an eaves gutter 2, a vertical pipe 3, a horizontal pipe 4, a first elbow 51, a second elbow 52, ​​protruding members 6-1, 6-2, 6-3, 6-4, a vertical pipe 7, a drain 8, as well as a third elbow 140 and a pipe 141.

[0104] The third elbow 140 changes the direction of the flow path. The third elbow 140 is a connecting joint that connects flow paths with different directions. The third elbow 140 has a curved pipe portion 1400 and sockets 1401 and 1402 at both ends of the curved pipe portion 1400. In the third elbow 140, the socket 1401 is connected to the downstream end 3b of the standpipe 3. The socket 1402 is connected to the piping 141. As an example, the material of the third elbow 140 may be rigid polyvinyl chloride. The dimensions of the third elbow 140 may be set in accordance with the standard JIS K 6739 "Rigid polyvinyl chloride pipe fittings for drainage," for example.

[0105] The pipe 141 is installed to discharge a fluid (rainwater in this embodiment) onto the second roof 10c. The pipe 141 is also called a sprinkler pipe.

[0106] The piping 141 includes a second horizontal pipe 142 and a fourth elbow 143 .

[0107] The second horizontal pipe 142 has a straight pipe shape. A cross section perpendicular to the central axis of the second horizontal pipe 142 is circular. The second horizontal pipe 142 is arranged so that the central axis of the second horizontal pipe 142 intersects the up-down direction (vertical direction). The second horizontal pipe 142 has an upstream end 142a and a downstream end 142b. The upstream end 142a is connected to the socket 1402 of the third elbow 140. The second horizontal pipe 142 has one or more discharge ports 142c between the upstream end 142a and the downstream end 142b. Figure 18 shows three discharge ports 142c. Each discharge port 142c penetrates the pipe wall of the second horizontal pipe 142. As an example, the inner diameter of the discharge ports 142c is 75 mm, and the discharge ports 142c are arranged at a pitch of 250 mm.

[0108] As an example, the material of the second horizontal pipe 142 is rigid polyvinyl chloride. The dimensions of the second horizontal pipe 142, such as 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."

[0109] The fourth elbow 143 changes the direction of the flow path. The fourth elbow 143 has a curved pipe portion 1430 and sockets 1431, 1432 at both ends of the curved pipe portion 1430. In the fourth elbow 143, the socket 1431 is connected to the downstream end 142b of the second horizontal pipe 142. The socket 1432 is the downstream end of the pipe 141. The socket 1432 is used as a discharge port at the end of the pipe 141. In this embodiment, the opening 1432a of the socket 1432 is partially blocked. Preferably, the opening 1432a is blocked by 50% or more. In other words, the flow path cross-sectional area of ​​the opening 1432a is reduced by 50% or more. This makes it easier for the fluid to be discharged from the discharge port 142c.

[0110] For example, the material of the fourth elbow 143 may be rigid polyvinyl chloride. The dimensions of the fourth elbow 143 may be set in accordance with the standard JIS K 6739 "Rigid polyvinyl chloride pipe joints for drainage," for example.

[0111] In the piping system 1D, the length of the piping 141 is 1.0 m or more. The length of the piping 141 is determined by the length of the second horizontal pipe 142. This allows the fluid to be discharged over a sufficient range of the second roof 10c.

[0112] In the piping system 1D, the distance L14 between the second elbow 52 and the third elbow 140 in the vertical direction is 2.0 m or more. This allows the flow of fluid from the upright pipe 3 to the piping 141 to be stabilized.

[0113] [1.5.2 Effects, etc.] The piping system 1D described above further includes a third elbow 140 connected to the downstream end 3b of the standpipe 3, and a pipe 141 connected downstream of the third elbow 140. The length of the pipe 141 is 1.0 m or more. An opening 1432a at the downstream end of the pipe 141 is blocked by 50% or more. The pipe 141 has one or more discharge ports 143c penetrating the pipe wall of the pipe 141 (second horizontal pipe 142). The distance L14 between the second elbow 52 and the third elbow 140 in the vertical direction is 2.0 m or more. This configuration allows the fluid to be stably discharged from the discharge ports 143c and the openings 1432a.

[0114] 1.6 Sixth embodiment 1.6.1 Configuration 19 is a schematic diagram of a piping system 1E according to embodiment 6. The piping system 1E includes a second eaves gutter 150 and piping 151 in addition to an eaves gutter 2, a vertical pipe 3, a horizontal pipe 4, a first elbow 51, a second elbow 52, ​​protruding members 6-1, 6-2, 6-3, and 6-4, a vertical pipe 7, and a drain 8.

[0115] The second eaves gutter 150 receives rainwater from, for example, the eaves of the building 10. The second eaves gutter 150 is installed under the eaves of the building. The second eaves gutter 150 is shaped like a long bucket. The second eaves gutter 150 forms a second flow path that extends in a direction intersecting the vertical direction. The second eaves gutter 150 has a bottom wall 150a. The bottom wall 150a forms the bottom wall of the second flow path.

[0116] The second eaves gutter 150 has a drop opening in the bottom wall 150a. The drop opening of the second eaves gutter 150 is connected to the manhole via a standpipe that is separate from the standpipe 3.

[0117] The second eaves gutter 150 overlaps at least a portion of the socket 521 of the second elbow 52 in the vertical direction. The second eaves gutter 150 has an opening 150b at a portion that overlaps with the socket 521 of the second elbow 52 in the vertical direction. The opening 150b is a through-hole that penetrates the bottom wall 150a of the second eaves gutter 150. The inner diameter of the opening 150b is larger than the outer diameter of the standpipe 3. The second eaves gutter 150 may be formed by extrusion molding of a resin material. The second eaves gutter 150 may include a core material to reinforce the strength of the entire second eaves gutter 150. The core material may be made of, for example, metal. As another example, the second eaves gutter 150 may be formed from a metal plate, for example, a steel plate (also called a coil).

[0118] The pipe 151 has a larger diameter than the standpipe 3. The pipe 151 penetrates the bottom wall 150a of the second flow path of the second eaves gutter 150 while being separated from the second flow path of the second eaves gutter 150. In this embodiment, the pipe 151 is arranged to penetrate an opening 150b in the bottom wall 150a of the second eaves gutter 150. The pipe 151 is also referred to as a penetration pipe. The pipe 151 has a first member 152 and a second member 153. As an example, the material of the first member 152 and the second member 153 may be rigid polyvinyl chloride.

[0119] The first member 152 has a first cylindrical portion 152a and a first flange portion 152b. The first cylindrical portion 152a covers the entire periphery of the opening 150b and penetrates the opening 150b. The first cylindrical portion 152a extends upward from the upper surface of the bottom wall 150a of the second eaves gutter 150 and downward from the lower surface of the bottom wall 150a. The position of the upper end of the first cylindrical portion 152a is set so that fluid is less likely to flow into the first cylindrical portion 152a from the second flow path of the second eaves gutter 150. In this embodiment, the upper end of the first cylindrical portion 152a is located above the upper end of the second eaves gutter 150. The lower end of the first cylindrical portion 152a is located below the lower surface of the bottom wall 150a of the second eaves gutter 150. The first flange 152b of the second eaves gutter 150 protrudes outward from the first cylindrical portion 152a and is disposed so as to contact the upper surface of the bottom wall 150a and to cover the entire periphery of the opening 150b.

[0120] The second member 153 has a second cylindrical portion 153a and a second flange portion 153b. The second cylindrical portion 153a covers the entire periphery of the first cylindrical portion 152a below the bottom wall 150a. The second flange portion 153b protrudes outward from the second cylindrical portion 153a and is disposed in contact with the lower surface of the bottom wall 150a so as to cover the entire periphery of the opening 150b.

[0121] In this embodiment, the first cylindrical portion 152a and the second cylindrical portion 153a are straight tubular, and the cross section perpendicular to the central axis thereof is circular. In this embodiment, the first flange portion 152b and the second flange portion 153b are plate-shaped, and the cross section perpendicular to the central axis thereof is circular.

[0122] In the piping system 1E, the standpipe 3 is arranged so as to pass through the piping 151. This allows the standpipe 3 to be arranged separately from the second flow path of the second eaves gutter 150, even if the second eaves gutter 150 is present.

[0123] In this embodiment, the inner diameter of the pipe 151 is 5 mm or more larger than the outer diameter of the standpipe 3. The inner diameter of the pipe 151 is determined by the inner diameter of the first cylindrical portion 152a.

[0124] [1.6.2 Effects, etc.] In the piping system 1E, the riser pipe 3 passes through a pipe 151 having a larger diameter than the riser pipe 3. The pipe 151 penetrates a bottom wall 150a of the second flow path while being separated from the second flow path extending in a direction intersecting the vertical direction. The inner diameter of the pipe 151 is 5 mm or more larger than the outer diameter of the riser pipe 3. This configuration allows the riser pipe 3 to be arranged separately from the second flow path.

[0125] 1.7 Seventh embodiment 1.7.1 Configuration 20 is a schematic diagram of a piping system 1F according to the seventh embodiment. The piping system 1F includes, in addition to the eaves gutter 2, the standpipe 3, the horizontal pipe 4, the first elbow 51, the second elbow 52, ​​the protruding members 6-1, 6-2, 6-3, and 6-4, the standpipe 7, and the drain 8, a second eaves gutter 160, a pipe 161, a tee 164, a second standpipe 1650, a third standpipe 1651, a second horizontal pipe 1652, a fourth standpipe 1653, a second drain 166, and a third elbow 167.

[0126] The second eaves gutter 160 receives rainwater from the eaves of the building 10, for example. The second eaves gutter 160 is installed under the eaves of the building. The second eaves gutter 160 is shaped like a long bucket. The second eaves gutter 160 forms a second flow path that extends in a direction intersecting the vertical direction. The second eaves gutter 160 has a bottom wall 160a. The bottom wall 160a constitutes the bottom wall of the second flow path. The second eaves gutter 160 has a first opening 160b and a second opening 160c in the bottom wall 160a. The first opening 160b is located in a portion that overlaps with the socket 521 of the second elbow 52 in the vertical direction. The first opening 160b is a through hole that penetrates the bottom wall 160a of the second eaves gutter 160. The inner diameter of the first opening 160b is larger than the outer diameter of the standpipe 3. The second opening 160c is used as a drop opening.

[0127] The second eaves gutter 160 may be formed by extrusion molding of a resin material. The second eaves gutter 160 may include a core material to reinforce the strength of the entire second eaves gutter 160. The core material may be made of metal, for example. As another example, the second eaves gutter 160 may be formed of a metal plate, for example, a steel plate (also called a coil).

[0128] The pipe 161 has a larger pipe diameter than the standpipe 3. For example, the pipe 161 is larger than the standpipe 3 by one size or more. The pipe 161 penetrates the bottom wall 160a of the second flow path of the second eaves gutter 160 while being separated from the second flow path of the second eaves gutter 160. In this embodiment, the pipe 161 is arranged to penetrate the first opening 160b of the bottom wall 160a of the second eaves gutter 160. The pipe 161 has a first member 162 and a second member 163. As an example, the material of the first member 162 and the second member 163 may be rigid polyvinyl chloride.

[0129] The first member 162 has a first cylindrical portion 162a and a first flange portion 162b. The first cylindrical portion 162a covers the entire periphery of the first opening 160b and penetrates the first opening 160b. The first cylindrical portion 162a does not extend above the upper surface of the bottom wall 160a of the second eaves gutter 160, but extends below the lower surface of the bottom wall 160a. The lower end of the first cylindrical portion 162a is below the lower surface of the bottom wall 160a of the second eaves gutter 160. The first flange portion 162b of the second eaves gutter 160 protrudes outward from the upper end of the first cylindrical portion 162a and is positioned so as to contact the upper surface of the bottom wall 160a and cover the entire periphery of the first opening 160b.

[0130] The second member 163 has a second cylindrical portion 163a and a second flange portion 163b. The second cylindrical portion 163a covers the entire periphery of the first cylindrical portion 162a below the bottom wall 160a. The second flange portion 163b protrudes outward from the second cylindrical portion 163a and is disposed in contact with the lower surface of the bottom wall 160a so as to cover the entire periphery of the first opening 160b.

[0131] In this embodiment, the first cylindrical portion 162a and the second cylindrical portion 163a are straight tubular, and the cross section perpendicular to the central axis thereof is circular. In this embodiment, the first flange portion 162b and the second flange portion 163b are plate-shaped, and the cross section perpendicular to the central axis thereof is circular.

[0132] The T-shirt 164 has a first receiving port 164a facing upward, a second receiving port 164b facing downward, and a third receiving port 164c facing sideways. The T-shirt 164 merges the fluid flowing in from the first receiving port 164a with the fluid flowing in from the third receiving port 164c, and allows the combined fluid to flow out from the second receiving port 164b. The angle between the central axis of the first receiving port 164a and the central axis of the third receiving port 164c is 90° or less. As an example, the angle between the central axis of the first receiving port 164a and the central axis of the third receiving port 164c is set to 88.83°. As an example, the material of the T-shirt 164 is hard polyvinyl chloride.

[0133] The first socket 164a is connected to the first opening 160b of the second eaves gutter 160 via a second standpipe 1650. The second socket 164b is connected to the manhole via a third standpipe 1651. The third socket 164c is connected to the second opening 160c of the second eaves gutter 160 via a second horizontal pipe 1652, a fourth standpipe 1653, and a third elbow 167.

[0134] The second standpipe 1650 connects the pipe 161 and the tee 164. In this embodiment, the second standpipe 1650 has a larger pipe diameter than the pipe 161. The second standpipe 1650 is straight. The cross section perpendicular to the central axis of the second standpipe 1650 is circular. The second standpipe 1650 is arranged so that the direction of the central axis of the second standpipe 1650 coincides with the up-down direction (vertical direction). The second standpipe 1650 has an upstream end 1650a and a downstream end 1650b. The upstream end 1650a is connected to the downstream end of the pipe 161. In this embodiment, the second cylindrical portion 163a of the second member 163 of the pipe 161 is inserted into the upstream end 1650a of the second standpipe 1650. The downstream end 1650 b is connected to the first socket 164 a of the cheese 164 .

[0135] The third standpipe 1651 is installed to drain water from the tee 164 into the manhole. In this embodiment, the third standpipe 1651 has the same pipe diameter as the second standpipe 1650. For example, the third standpipe 1651 is the same size as the second standpipe 1650. The third standpipe 1651 is a straight pipe. The cross section perpendicular to the central axis of the third standpipe 1651 is circular. The third standpipe 1651 is arranged so that the direction of the central axis of the third standpipe 1651 coincides with the up-down direction (vertical direction). The upstream end of the third standpipe 1651 is connected to the second receiver 164b of the tee 164. The downstream end of the third standpipe 1651 is inserted into the manhole.

[0136] The second drain 166 is disposed at the second opening 160c of the second eaves gutter 160. The second drain 166 does not necessarily have to have a configuration that can contribute to the occurrence of the siphoning phenomenon. The second drain 166 may have a well-known configuration.

[0137] The third elbow 167 changes the direction of the flow path. The third elbow 167 is a connector that connects flow paths with different directions. The third elbow 167 has a curved pipe portion 1670 and sockets 1671 and 1672 at both ends of the curved pipe portion 1670. The socket 1672 of the third elbow 167 is connected to the second drain 166 via the fourth upright pipe 1653, and thereby to the second opening 160c. The socket 1671 is connected to the third socket 164c of the tee 164 via the second horizontal pipe 1652. For example, the material of the third elbow 167 may be rigid polyvinyl chloride. The dimensions of the third elbow 167 may be set in accordance with the standard JIS K 6739, "Rigid Polyvinyl Chloride Pipe Joints for Drainage."

[0138] The fourth standpipe 1653 connects between the second opening 160c and the third elbow 167. The fourth standpipe 1653 is straight. The cross section perpendicular to the central axis of the fourth standpipe 1653 is circular. The fourth standpipe 1653 is arranged so that the direction of the central axis of the fourth standpipe 1653 coincides with the up-down direction (vertical direction). The fourth standpipe 1653 has an upstream end 1653a and a downstream end 1653b. The upstream end 1653a is connected to the second drain 166. The downstream end 1653b is connected to the socket 1672 of the third elbow 167.

[0139] The second horizontal pipe 1652 connects between the third elbow 167 and the tee 164. The second horizontal pipe 1652 is straight. The cross section perpendicular to the central axis of the second horizontal pipe 1652 is circular. The second horizontal pipe 1652 is arranged so that the direction of the central axis of the second horizontal pipe 1652 intersects the up-down direction (vertical direction). The second horizontal pipe 1652 has an upstream end 1652a and a downstream end 1652b. The upstream end 1652a is connected to the socket 1671 of the third elbow 167. The downstream end 1652b is connected to the third socket 164c of the tee 110.

[0140] As an example, second riser pipe 1650, third riser pipe 1651, second horizontal pipe 1652, and fourth riser pipe 1653 have the same pipe diameter. Second riser pipe 1650, third riser pipe 1651, second horizontal pipe 1652, and fourth riser pipe 1653 are made of rigid polyvinyl chloride. The dimensions of second riser pipe 1650, third riser pipe 1651, second horizontal pipe 1652, and fourth riser pipe 1653, such as 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 Pipe."

[0141] In the piping system 1F, the downstream end 3b of the standpipe 3 is inserted from above into the first cylindrical portion 162a of the piping 161. As a result, the downstream end 3b of the standpipe 3 is inserted into the first opening 160b. The length L16 of the portion of the standpipe 3 inserted into the first opening 160b is 40 mm or more, which stabilizes the flow of fluid from the second flow path to the first opening 160b and the flow of fluid from the standpipe 3 to the first opening 160b.

[0142] [1.7.2 Effects, etc.] The piping system 1F described above further includes a tee 164 having a first receiving port 164a facing upward, a second receiving port 164b facing downward, and a third receiving port 164c facing sideways. The first receiving port 164a is connected to a first opening 160b in a bottom wall 160a of a second flow path extending in a direction intersecting the vertical direction. The third receiving port 164c is connected to a second opening 160c in the bottom wall 160a of the second flow path. The downstream end 3b of the riser pipe 3 is inserted into the first opening 160b. The length L16 of the portion of the riser pipe 3 inserted into the first opening 160b is 40 mm or more. This configuration stabilizes the flow of fluid from the second flow path to the first opening 160b and the flow of fluid from the riser pipe 3 to the first opening 160b.

[0143] 1.8 Eighth embodiment 1.8.1 Configuration 21 is a schematic diagram of a piping system 1G according to an eighth embodiment. The piping system 1G includes, in addition to the eaves gutter 2, the standpipe 3, the horizontal pipe 4, the first elbow 51, the second elbow 52, ​​the protruding members 6-1, 6-2, 6-3, and 6-4, the standpipe 7, and the drain 8, a second eaves gutter 160, a pipe 161, a tee 164G, a second standpipe 1650, a third standpipe 1651, a second horizontal pipe 1652, a second drain 166, and a third elbow 167G.

[0144] Cheese 164G has a first socket 164a, a second socket 164b, and a third socket 164c, similar to Cheese 164. In Cheese 164G, the angle between the central axis of first socket 164a and the central axis of third socket 164c is 45°.

[0145] Similar to the third elbow 167, the third elbow 167G has a curved pipe portion 1670 and sockets 1671 and 1672 on both ends of the curved pipe portion 1670. In the third elbow 167G, the angle between the central axes of the sockets 1671 and 1672 is 45°.

[0146] In the piping system 1G as well, the downstream end 3b of the standpipe 3 is inserted from above into the first cylindrical portion 162a of the piping 161. As a result, the downstream end 3b of the standpipe 3 is inserted into the first opening 160b. The length L16 of the portion of the standpipe 3 inserted into the first opening 160b is 40 mm or more, which stabilizes the flow of fluid from the second flow path to the first opening 160b and the flow of fluid from the standpipe 3 to the first opening 160b.

[0147] [1.8.2 Effects, etc.] The piping system 1G described above further includes a tee 164G having a first receiving port 164a facing upward, a second receiving port 164b facing downward, and a third receiving port 164c facing sideways. The first receiving port 164a is connected to a first opening 160b in a bottom wall 160a of a second flow path extending in a direction intersecting the vertical direction. The third receiving port 164c is connected to a second opening 160c in the bottom wall 160a of the second flow path. The downstream end 3b of the riser pipe 3 is inserted into the first opening 160b. The length L16 of the portion of the riser pipe 3 inserted into the first opening 160b is 40 mm or more. This configuration stabilizes the flow of fluid from the second flow path to the first opening 160b and the flow of fluid from the riser pipe 3 to the first opening 160b.

[0148] 1.9 Ninth embodiment 1.9.1 Configuration 22 is an exploded perspective view of the downstream side of the second elbow 52 of the piping system according to the ninth embodiment. The piping system according to the ninth embodiment differs from the piping system 1 according to the first embodiment in a protrusion member 6H and a standpipe 3H.

[0149] The protruding member 6H is located downstream of the second elbow 52. More specifically, the protruding member 6H is located on the inner circumferential side of the second elbow 52 within the standpipe 3H, which is a straight pipe section downstream of the second elbow 52, ​​and is used to partially reduce the flow path cross-sectional area of ​​the standpipe 3H. The protruding member 6H is located at the upstream end 3a of the standpipe 3H. In this embodiment, the protruding member 6H is not formed integrally with the standpipe 3H, but is a separate body. In other words, the protruding member 6H and the standpipe 3H are formed separately and then joined to each other.

[0150] The protruding member 6H has a different shape from the protruding member 6. The shape of the protruding member 6H will be described in more detail below.

[0151] Fig. 23 is a cross-sectional view of a downstream portion of the second elbow 52 of the piping system according to this embodiment. Fig. 24 is a cross-sectional view taken along line EE in Fig. 23. Fig. 25 is a cross-sectional view of a portion of a standpipe 3H of the piping system according to this embodiment, with the standpipe 3H cut away. Fig. 26 is a plan view of a protruding member 6H and a standpipe 3H according to this embodiment. Fig. 27 is a bottom view of a protruding member 6H and a standpipe 3H according to this embodiment. Fig. 28 is a cross-sectional view taken along line IX-IX in Fig. 24. Fig. 29 is a cross-sectional view taken along line XX in Fig. 24. Fig. 30 is a cross-sectional view taken along line XI-XI in Fig. 24. Fig. 31 is a cross-sectional view taken along line XII-XII in Fig. 24. Fig. 32 is a cross-sectional view taken along line XIII-XIII in Fig. 24.

[0152] As shown in Fig. 23, the protruding member 6H is disposed so as to protrude from a first wall surface 30b on the inner periphery side of the standpipe 3H toward a second wall surface 30c on the outer periphery side of the standpipe 3H. The first wall surface 30b is a portion of the inner periphery side of the second elbow 52 on the inner periphery surface 30a of the standpipe 3H (for example, half of the inner periphery side). The second wall surface 30c is a portion of the inner periphery surface 30a of the standpipe 3H on the outer periphery side of the second elbow 52 (for example, half of the outer periphery side). The inner periphery surface 30a is composed of the first wall surface 30b and the second wall surface 30c.

[0153] As shown in Fig. 23, the protruding member 6H has a contact surface 60 that comes into contact with the inner circumferential surface 30a of the standpipe 3H. As shown in Fig. 26 and Fig. 27, the contact surface 60 has a convex shape when viewed from the direction of the central axis C3 of the standpipe 3H. 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 3H.

[0154] As shown in FIGS. 23 to 27, the protrusion member 6H 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 located on the opposite side of the protrusion member 6H from the contact surface 60 and can come into contact with the fluid flowing through the standpipe 3H. As shown in FIGS. 23 to 25, the main surface 61 extends from the first end 6a to the second end 6b. As shown in FIGS. 26 and 27, the main surface 61 faces the center of the standpipe 3H when viewed from the direction of the central axis C3 of the standpipe 3H. The first side surface 62 and the second side surface 63 are located on both sides of the main surface 61 when viewed from the direction of the central axis C3 of the standpipe 3H. In FIG. 26, the first side surface 62 is located on the left side of the main surface 61, and the second side surface 63 is located on the right side of the main surface 61.

[0155] In the protrusion member 6H, the main surface 61 and the first and second side surfaces 62, 63 can come into contact with the fluid flowing inside the standpipe 3H. As shown in Fig. 22, the protrusion member 6H 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. Because the main surface 61 and the first and second side surfaces 62, 63 can 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, as this can be expected to improve the flow rate.

[0156] The protrusion member 6H 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 make it easier for the flow F2 to separate from the flow F1. The first separation wall 64 is located between the main surface 61 and the first side surface 62. In this embodiment, the first separation wall 64 is the boundary between the main surface 61 and the first side surface 62. In other words, the boundary between the main surface 61 and the first side surface 62 forms a wall between a flow path having the main surface 61 as its bottom surface and a flow path having the first side surface 62 as its 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.

[0157] The protrusion member 6H 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 make it easier for the flow F3 to separate from the flow F1. The second separation wall 65 is located between the main surface 61 and the second side surface 63. In this embodiment, the second separation wall 65 is the boundary between the main surface 61 and the second side surface 63. In other words, the boundary between the main surface 61 and the second side surface 63 forms a wall between a flow path having the main surface 61 as its bottom surface and a flow path having the second side surface 63 as its 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.

[0158] As can be seen from FIGS. 23, 24, and 26 to 32, the shape (cross-sectional shape) of the protruding member 6H seen from the direction of the central axis C3 of the vertical pipe 3H changes along the direction of the central axis C3 of the vertical pipe 3H.

[0159] As shown in FIG. 23, the height of the protrusion member 6H varies along the direction of the central axis C3 of the standpipe 3H. In this embodiment, the protrusion member 6H has a top 6c between the first end 6a and the second end 6b. The top 6c is the highest part of the protrusion member 6H. The height of the protrusion member 6H increases monotonically from the first end 6a toward the top 6c. The height of the protrusion member 6H decreases monotonically from the top 6c toward the second end 6b. The protrusion member 6H minimizes the flow path cross-sectional area of ​​the standpipe 3H at the top 6c.

[0160] 23, in a cross section perpendicular to the width direction of the protruding member 6H, the main surface 61 includes a curved shape at the apex 6c that protrudes toward the second wall surface 30c. This improves 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 produce the Coanda effect on the downstream side of the second elbow 52. In other words, the main surface 61 only needs to have a shape that produces the Coanda effect on the downstream side of the second elbow 52. This improves the flow rate while enabling a compact design.

[0161] As can be seen from FIGS. 26 to 32, the shape of the main surface 61 seen from the direction of the central axis C3 of the vertical pipe 3H changes along the direction of the central axis C3 of the vertical pipe 3H.

[0162] 26 and 28, when viewed from the direction of the central axis C3 of the standpipe 3H, at least a portion of the main surface 61 has a concave shape. At least a portion 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 standpipe 3H, the radius of curvature of at least a portion of the main surface 61 (first end 6a) is equal to or smaller than the radius of curvature of the inner circumferential surface 30a of the standpipe 3H. This reduces pressure loss in the protruding member 6H.

[0163] As shown in FIGS. 26 to 30, 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 standpipe 3H changes from a concave shape to a convex shape from the first end 6a to the second end 6b. This facilitates flow along the main surface 61 of the protruding member 6H. In this embodiment, as shown in FIG. 30, the shape of the main surface 61 as viewed from the direction of the central axis C3 of the standpipe 3H is convex at the top 6c. The shape of the main surface 61 as viewed from the direction of the central axis C3 of the standpipe 3H is convex in the range from the top 6c to the second end 6b. In this embodiment, the protruding member 6H has a flat portion 6d between the first end 6a and the top 6c. As shown in FIG. 29, 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 standpipe 3H.

[0164] Within the concave area 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 6H. Within the convex area 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 6H. 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 6H.

[0165] As can be seen from FIGS. 26 to 32, 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 3H change along the direction of the central axis C3 of the vertical pipe 3H.

[0166] 26 and 28, when viewed from the direction of the central axis C3 of the vertical pipe 3H, at least a portion of the first side surface 62 is concave. At least a portion 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 has a concave shape at the first end 6a. This reduces pressure loss at the protruding member 6H.

[0167] 26 and 28, when viewed from the direction of the central axis C3 of the vertical pipe 3H, at least a portion of the second side surface 63 is concave. At least a portion 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 has a concave shape at the first end 6a. This reduces pressure loss at the protruding member 6H.

[0168] The shape of the first side surface 62 when viewed from the direction of the central axis C3 of the upright pipe 3H remains concave from the first end 6a toward the second end 6b. As can be seen from Figures 30 to 32, 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 6H.

[0169] The shape of the second side surface 63, as viewed from the direction of the central axis C3 of the upright pipe 3H, remains concave from the first end 6a to the second end 6b. As can be seen from Figures 30 to 32, the depth of the concave shape of the second side surface 63 becomes shallower from the apex 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 6H.

[0170] See Figure 24. In the protrusion member 6H, the first side surface 62 and the second side surface 63 are symmetrical with respect to the center line of the protrusion member 6H along the central axis C3 of the standpipe 3H. This can improve the flow rate.

[0171] As shown in FIG. 22, the width of the protruding member 6H varies along the central axis C3 of the standpipe 3H. The width of the protruding member 6H refers to the width of the portion of the protruding member 6H closest to the inner circumferential surface 30a of the standpipe 3H. In this embodiment, the width of the protruding member 6H corresponds to the width of the contact surface 60 of the protruding member 6H. The protruding member 6H 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 width change changes. The first portion 6e is located between the first end 6a and the apex 6c, more specifically, the flat portion 6d. The second portion 6f is located between the apex 6c and the second end 6b. The third portion 6g is located between the second portion 6f and the second end 6b. The width of the protruding member 6H increases monotonically from the first end 6a to the first portion 6e. The width of the protruding member 6H monotonically decreases from the first portion 6e to the second portion 6f. The width of the protruding member 6H monotonically increases from the second portion 6f to the third portion 6g. The width of the protruding member 6H monotonically decreases from the third portion 6g to the second end 6b. The width of the protruding member 6H is largest at the first portion 6e. As shown in FIG. 26, the maximum width of the protruding member 6H (the width at the first portion 6e) as viewed from the direction of the central axis C3 of the standpipe 3H is defined as W1. If the inner diameter of the standpipe 3H is d, then 0.5d≦W1≦0.9d holds. 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 standpipe 3H is defined as W2, then 0.3d≦W2≦0.7d holds. W2≦W1.

[0172] 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 6H. In this embodiment, the width of the main surface 61 decreases monotonically from the first end 6a to the second end 6b.

[0173] The first side surface 62 includes a portion whose width increases from the first end 6a to 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 to 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.

[0174] The second side surface 63 includes a portion whose width increases from the first end 6a to the second end 6b. More specifically, the portion of the second side surface 63 on the first end 6a side increases in width from the first end 6a to 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.

[0175] The first and second separation walls 64 and 65 are formed on a portion of the protruding member 6H, not the entire portion, in the direction of the central axis C3 of the standpipe 3H. More specifically, the first and second separation walls 64 and 65 are present in a predetermined range from the first end 6a along the direction of the central axis C3 of the standpipe 3H. The predetermined range is the range from the first end 6a to the flat portion 6d.

[0176] 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 and F3 along the first and second side faces 62 and 63 from the flow F1 along the main face 61 on the upstream side of the protrusion member 6H, and allows the flows F2 and F3 along the first and second side faces 62 and 63 to smoothly merge with the flow F1 along the main face 61 on the downstream side of the protrusion member 6H.

[0177] The heights of the first separation wall 64 and the second separation wall 65 decrease from the first end 6a to the second end 6b. This configuration separates the flows F2 and F3 along the first and second side faces 62 and 63 from the flow F1 along the main face 61 on the upstream side of the protrusion member 6H, and allows the flows F2 and F3 along the first and second side faces 62 and 63 to smoothly merge with the flow F1 along the main face 61 on the downstream side of the protrusion member 6H.

[0178] 23 and 30. The diameter of the standpipe 3H 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 standpipe 3H (i.e., the length of the protrusion member 6H) is L. For the protrusion member 6H, it is preferable that 0.5d≦L≦5.0d. This can further reduce the occurrence of pressure loss due to separation downstream from the second elbow 52. Therefore, the flow rate can be improved while enabling miniaturization.

[0179] See Figure 23. The apex 6c of the protrusion member 6H is the portion of the standpipe 3H where the flow path cross-sectional area is smallest. The distance between the first end 6a and the apex 6c in the direction of the central axis C3 of the standpipe 3H is defined as D1. In the protrusion member 6H, it is preferable that 0.1L≦D1≦0.5L. This can further reduce the occurrence of pressure loss due to separation downstream from the second elbow 52. Therefore, the flow rate can be improved while enabling miniaturization.

[0180] See Figure 23. The distance between the apex 6c and the second end 6b in the direction of the central axis C3 of the vertical pipe 3H is defined as D3. D3 = L - D1. In the protruding member 6H, it is preferable that D3 > D1. In other words, it is preferable that the apex 6c is closer to the first end 6a than the second end 6b. This can further reduce the occurrence of pressure loss due to separation downstream from the second elbow 52. Therefore, it is possible to improve the flow rate while enabling miniaturization.

[0181] See Figure 30. When viewed from the direction of the central axis C3 of the standpipe 3H, the distance between the top 6c of the protruding member 6H and the second wall surface 30c is defined as D2. It is preferable that the relationship between the top 6c and the second wall surface 30c of the protruding member 6H is 0.60d≦D2≦0.95d. This can further reduce pressure loss caused by separation downstream from the second elbow 52. This can therefore improve the flow rate while enabling miniaturization.

[0182] The height of the top 6c of the protruding member 6H as viewed from the direction of the central axis C3 of the upright pipe 3H is defined as H. H=d-D2. It is preferable that the protruding member 6H has a height of 0.05d≦H≦0.40d. This can further reduce the occurrence of pressure loss due to separation downstream from the second elbow 52. This can improve the flow rate while enabling miniaturization.

[0183] The maximum flow cross-sectional area of ​​the vertical pipe 3H is A. The maximum flow cross-sectional area A can be calculated from the inner diameter d of the vertical pipe 3H. In other words, A = π(d / 2) 2 The cross-sectional area of ​​the protruding member at the top 6c is defined as A1. In the protruding member 6H, A1 / A≦0.5, preferably A1 / A≦0.4. This can further reduce pressure loss caused by separation downstream from the second elbow 52. Therefore, the flow rate can be improved while enabling compactness. The minimum value of the flow path cross-sectional area of ​​the standpipe 3H is defined as A2. A2 is the flow path cross-sectional area at the top 6c of the protruding member 6H. A2 is A−A1. In the protruding member 6H, 0.5≦A2 / A<1, preferably 0.6≦A2 / A<1. This can further reduce pressure loss caused by separation downstream from the second elbow 52. Therefore, the flow rate can be improved while enabling compactness.

[0184] As shown in FIGS. 23, 25, and 26, the protrusion member 6H has a contact end surface 66 at the first end 6a. In this embodiment, the inner diameter of the standpipe 3H is larger than the inner diameter of the curved pipe portion 520 of the second elbow 52. The contact end surface 66 is provided to compensate for the difference in inner diameter between the standpipe 3H and the curved pipe portion 520 of the second elbow 52. As shown in FIG. 23, the presence of the contact end surface 66 eliminates a step between the inner surface 520a on the inner periphery of the curved pipe portion 520 of the second elbow 52 and the main surface 61 of the protrusion member 6H. The corner portion 520c shown in FIG. 23 extends over the entire area that curves smoothly from the socket 521 to the socket 522, and the distance between the first end 6a and the corner portion 520c is zero.

[0185] As shown in FIG. 26, the protrusion member 6H has a protrusion 67. The protrusion 67 is used to join or position the standpipe 3H and the protrusion member 6H. The protrusion 67 is arranged on the contact surface 60. The protrusion 67 is shaped to fit into the recessed portions 3d of the standpipe 3H. In this embodiment, the standpipe 3H has a pair of recessed portions 3d on the edge of the upstream end portion 3a. The recessed portions 3d are formed as notches. The protrusion member 6H has a pair of protrusions 67 that fit into the pair of recessed portions 3d, respectively. By fitting the pair of protrusions 67 into the pair of recessed portions 3d, the protrusion member 6H is positioned relative to the standpipe 3H.

[0186] As described above, the protruding member 6H is disposed on the inner peripheral surface 30a of the standpipe 3H. As a result, the flow path cross-sectional area of ​​the standpipe 3H is not constant, and there is a reduced portion where the flow path cross-sectional area of ​​the standpipe 3H is smaller than the maximum cross-sectional area of ​​the standpipe 3H. The protruding member 6H is located closer to the upstream end 3a of the standpipe 3H than to the downstream end 3b of the standpipe 3H. In this embodiment, the protruding member 6H is located at the upstream end 3a of the standpipe 3H. In other words, the protruding member 6H reduces the flow path at the upstream end 3a of the standpipe 3H that connects to the second elbow 52.

[0187] The protruding member 6H described above is located at the end (upstream end 3a) of the riser pipe 3H on the second elbow 52 side. In particular, the protruding member 6H is located on the inner circumferential side of the second elbow 52 of the riser pipe 3H (left side in FIG. 23). In the protruding member 6H, the apex 6c is closer to the first end 6a than the second end 6b, and the first end 6a is closer to the second elbow 52 than the second end 6b. In the protruding member 6H, a fluid flow occurs from the first end 6a toward the second end 6b.

[0188] The presence of the protruding members 6H is expected to (1) make it easier for the fluid to flow along the pipe wall than if the protruding members 6H were not present, and (2) reduce the number of areas where pressure loss may occur. Therefore, like the protruding members 6, the protruding members 6H can improve the flow rate while enabling miniaturization. The protruding members 6H are located inside the standpipe 3H, and are therefore less noticeable when viewed as part of the piping system as a whole. This is expected to improve the aesthetic appearance of the piping system as a whole.

[0189] [1.9.2 Effects, etc.] In the piping system described above, the straight pipe portion is the upright pipe 3H. The protruding member 6H is located at the upstream end 3a of the upright pipe 3H. The protruding member 6H is separate from the upright pipe 3H. This configuration can improve the degree of freedom in arranging the protruding member 6H.

[0190] 1.10 Tenth embodiment 1.10.1 Configuration 33 is a vertical cross-sectional view showing the structure around the corner 520c of the second elbow 52 of the piping system according to the tenth embodiment. The piping system according to the tenth embodiment differs from the piping system 1 according to the first embodiment in terms of protrusion members 6J-1 and 6J-3.

[0191] 33, the first end 6a of the protruding member 6J-1 is disposed toward the corner 520c on the inner circumferential side of the second elbow 52, ​​and forms a gap 2000a between the first end 6a and the corner 520c. The length of the gap 2000a, i.e., the distance D4 between the first end 6a and the corner 520c, is 20 mm or less.

[0192] Similarly, the first end 6a of the protruding member 6J-3 is disposed toward the corner 520c on the inner circumferential side of the second elbow 52, ​​forming a gap 2000c between the first end 6a and the corner 520c. The length of the gap 2000c, i.e., the distance D5 between the first end 6a and the corner 520c, is 20 mm or less.

[0193] As described above, while gaps 2000a and 2000c are permitted between first end 6a and corner 520c, the lengths of gaps 2000a and 2000c (distances D4 and D5) are each set to 20 mm or less. This prevents a significant reduction in the pressure loss reduction performance of protruding members 6J-1 and 6J-3, and does not require strict management in on-site construction and assembly processes, which is expected to reduce manufacturing costs, simplify the need for strict management of construction variations, and reduce problems with product quality.

[0194] The upper limit values ​​of the distances D4 and D5 are not limited to being uniformly equal to or less than 20 mm, and may be changed, for example, according to the pipe diameters (or inner diameters) of the second elbow 52, ​​the upright pipe 3, and the horizontal pipe 4. An example thereof is shown below. <Pipe diameter (nominal diameter)> <Distance D4, D5> Less than 75 3mm or less 75 or more but less than 100 5mm or less 100 or more but less than 125 10mm or less 125 or more 20mm or less

[0195] 33 shows protrusion members 6J-1 and 6J-3 corresponding to protrusion members 6-1 and 6-3 of embodiment 1, but the same applies to protrusion members 6J-2 and 6J-4 (not shown) corresponding to protrusion members 6-2 and 6-4 of embodiment 1. That is, a gap may be provided between the first end 6a of each of protrusion members 6J-2 and 6J-4 and the corner portion 510c of the first elbow 51, and the length of the gap may be set to 20 mm or less or to a length equal to or less than the upper limit value according to the pipe diameter.

[0196] 33 shows a case where the cross sections of the second elbow 52, ​​the upright pipe 3, and the horizontal pipe 4 are all circular, and a circular pipeline is shown, but this is not limited to this case and the same applies to a rectangular pipeline with a rectangular cross section. That is, the first end 6a of the protruding member 6 is arranged toward the corner on the inner periphery of the elbow with a rectangular cross section, a gap is provided between the first end 6a and the corner (smoothly rounded portion) of the elbow, and the length of the gap is set to 20 mm or less or to a length not exceeding the upper limit value according to the pipe diameter.

[0197] Taking the first to eleventh embodiments together, the distance between the first end 6a and the corner 520c may be 0 mm or more and 20 mm or less, which is expected to improve the overall quality of the piping system having the protruding member 6.

[0198] (Actions and Effects) The piping system described above forms a flow path and includes a horizontal pipe 4, a vertical pipe 3, a first socket 522 for inserting the end of the horizontal pipe 4, a second socket 521 for inserting the end of the vertical pipe 3, an elbow 52 having an inner corner 520c between the first socket 522 and the second socket 521, and protrusions 6J-1 and 6J-3 arranged on the inner side of the elbow 52 at the end 4b of the horizontal pipe 4 or the end 3a of the vertical pipe 3 to partially reduce the flow path cross-sectional area of ​​the flow path. The protrusions 6J-1 and 6J-3 have a first end 6a and a second end 6b in the longitudinal direction, with the first end 6a facing the corner 520c of the elbow 52, ​​and the distances D4 and D5 between the first end 6a and the corner 520c are between 0 mm and 20 mm. This configuration enables miniaturization while improving flow rate. In addition, the overall quality of the piping system having the protruding members 6J-1 and 6J-3 can be expected to improve.

[0199] In the piping system described above, when the diameters of the horizontal pipe 4 and the vertical pipe 3 are each less than 75, the distances D4 and D5 are 3 mm or less, when the diameters of the horizontal pipe 4 and the vertical pipe 3 are 75 or more and less than 100, the distances D4 and D5 are 5 mm or less, when the diameters of the horizontal pipe 4 and the vertical pipe 3 are 100 or more and less than 125, the distances D4 and D5 are 10 mm or less, and when the diameters of the horizontal pipe 4 and the vertical pipe 3 are 125 or more, the distances D4 and D5 are 20 mm or less. This configuration can improve the flow rate while enabling miniaturization, and is expected to improve the overall quality of the piping system having the protrusion members 6J-1 and 6J-3.

[0200] 1.11 Eleventh embodiment 1.11.1 Configuration 34 is a plan view showing a protrusion member 6K-1 arranged on the standpipe 3 of the piping system according to embodiment 11. The piping system according to embodiment 11 differs from the piping system 1 according to embodiment 1 in the protrusion member 6K-1.

[0201] As shown in FIG. 34, the protrusion member 6K-1 is allowed to rotate around the central axis C3 from a reference position indicated by a solid line to a position rotated within a predetermined angle range (see dotted line).

[0202] 34, in the reference position indicated by the solid line, the center line of the protrusion member 6K-1 in the width direction is parallel to and overlaps with the central axis C4. Furthermore, the central plane formed by the center line of the protrusion member 6K-1 in the width direction is parallel to and overlaps with the plane including the central axes C3 and C4. In other words, the reference position for angle θ1=0 is a position in which the plane passing through the central axes C3 and C4 of the two sockets 521 and 522 of the elbow 52, ​​into which the protrusion member 6K-1 is inserted, passes through the center of the protrusion member 6K-1 in the width direction.

[0203] An angle θ1 from the reference position (center axis C4) indicated by the solid line to the rotation position (center line / center plane C8) indicated by the dotted line is set to 10 degrees or less.

[0204] As described above, the rotation angle of the protruding member 6K-1 relative to the reference position is set to between 0 and 10 degrees inclusive in the direction of rotation around the central axis C3 of the vertical pipe 3 on which the protruding member 6K-1 is arranged. This prevents a significant reduction in the pressure loss reduction performance of the protruding member 6K-1, and is expected to have the effects of reducing manufacturing costs, simplifying the need for strict management of construction variations, and reducing problems with product quality.

[0205] 34 illustrates protrusion member 6K-1 corresponding to protrusion member 6-1 of embodiment 1, but the same applies to protrusion members 6K-2, 6K-3, and 6K-4 (not shown) corresponding to protrusion members 6-2, 6-3, and 6-4 of embodiment 1. That is, the rotation angle of each of protrusion members 6K-2, 6K-3, and 6K-4 with respect to the reference posture may be set to between 0 degrees and 10 degrees.

[0206] (Actions and Effects) The piping system described above forms a flow path and includes a horizontal pipe 4, a vertical pipe 3, an elbow 52 having a first socket 522 for inserting the end of the horizontal pipe 4 and a second socket 521 for inserting the end of the vertical pipe 3, and a protruding member 6K-1 disposed on the inner periphery of the elbow 52 at the end 3a of the vertical pipe 3 to partially reduce the cross-sectional area of ​​the flow path. The rotation angle of the protruding member 6K-1 around the central axis C3 of the vertical pipe 3 on which the protruding member 6K-1 is disposed is between 0 and 10 degrees relative to the reference position. This configuration improves flow rate while enabling compactness. Furthermore, the overall quality of the piping system incorporating the protruding member 6K-1 is expected to be improved.

[0207] [2. Modifications] The embodiments of the present disclosure are not limited to the above-described embodiments. The above-described embodiments can be modified in various ways depending on the design, etc., as long as the object of the present disclosure can be achieved. Modifications of the above-described embodiments are listed below. The modifications described below can be applied in appropriate combinations.

[0208] In the following, when reference is made to symbols used in embodiment 1, even if they are applicable to any of the above embodiments 1 to 9, this is simply for the purpose of simplifying the description and is not intended to exclude application to embodiments 2 to 9.

[0209] In one modified example, the piping system 1 does not necessarily have to include all of the protruding members 6-1 to 6-4, and may include at least one of the protruding members 6-1 to 6-4. If the piping system 1 does not include the protruding member 6-4, it does not necessarily have to include the standpipe 7.

[0210] In one modified example, the protruding members 6-1 to 6-4 do not necessarily have to have the same configuration or structure.The protruding members 6-1 to 6-4 do not necessarily have to have the same shape and size, but may have different shapes and sizes.

[0211] In one modified example, the straight pipe sections such as the vertical pipe 3, horizontal pipe 4, and vertical pipe 7 may be made up of a plurality of pipe materials instead of a single pipe material.

[0212] In one variant, the material of the components of the piping system 1, such as the straight pipe sections such as the vertical pipe 3, horizontal pipe 4, and vertical pipe 7, or the fittings such as the first and second elbows 51, 52, does not necessarily have to be rigid polyvinyl chloride, but may be determined according to the requirements of the piping system 1, and may be, for example, a synthetic resin such as polyethylene or a metal.

[0213] In one modified example, the shape and size of part or all 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 shapes of the first and second elbows 51, 52, the upright pipe 3, and the horizontal pipe 4 may be polygonal rather than circular.

[0214] In one modified example, the piping system 1 does not necessarily have to include the eaves gutter 2. For example, if the building 10 has a structure with an inlet (water collection port) such as a balcony, the first elbow 51 of the piping system 1 may be connected to the inlet of the building 10.

[0215] In one modified example, the drain 8 may have a structure that is generally not thought 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. This also applies to the second drains 115, 166.

[0216] In one modification of the fifth embodiment, the pipe 141 may not include the fourth elbow 143.

[0217] In one modified example, the piping system 1 is not limited to a gutter system, which is a type of drainage system, but may also be applied to other drainage systems such as a sewerage system, or to water supply systems such as a drinking water system. In other words, the protrusion member or piping member can be used in a system that supplies or drains water. Furthermore, the piping system 1 can be a piping system for transporting a target fluid within a facility such as a factory. In other words, the fluid transported by the piping system 1 is not limited to rainwater.

[0218] [3. Aspects] As is apparent from the above-described embodiment and modifications, the present disclosure includes the following aspects.

[0219] [Aspect 1] A piping system forming a flow path, Horizontal pipe and Vertical pipe and an elbow having a first socket into which an end of the horizontal pipe is inserted, a second socket into which an end of the vertical pipe is inserted, and an inner corner portion between the first socket and the second socket; a protruding member disposed on an inner peripheral side of the elbow at the end of the horizontal pipe or the end of the vertical pipe so as to partially reduce a flow path cross-sectional area of ​​the flow path, The protrusion member has a first end and a second end in a longitudinal direction, the first end is positioned toward the corner of the elbow, and the distance between the first end and the corner is greater than or equal to 0 mm and less than or equal to 20 mm.

[0220] [Aspect 2] When the diameters of the horizontal pipe and the vertical pipe are each less than 75 mm, the distance is 3 mm or less; When the diameters of the horizontal pipe and the vertical pipe are 75 mm or more and less than 100 mm, the distance is 5 mm or less; When the diameters of the horizontal pipe and the vertical pipe are equal to or greater than 100 mm and less than 125 mm, the distance is equal to or less than 10 mm; When the diameters of the horizontal pipe and the vertical pipe are 125 mm or more, the distance is 20 mm or less. 2. The piping system of embodiment 1.

[0221] [Aspect 3] The cross section of the flow channel is circular or rectangular. The piping system according to aspect 1 or aspect 2.

[0222] [Aspect 4] A piping system forming a flow path, Horizontal pipe and Vertical pipe and an elbow having a first socket into which the end of the horizontal pipe is inserted and a second socket into which the end of the vertical pipe is inserted; a protruding member disposed on an inner peripheral side of the elbow at the end of the horizontal pipe or the end of the vertical pipe so as to partially reduce a flow path cross-sectional area of ​​the flow path, A piping system, wherein the rotation angle of the protrusion member around the central axis of the horizontal pipe or the vertical pipe on which the protrusion member is arranged is greater than or equal to 0 degrees and less than or equal to 10 degrees with respect to a reference attitude.

[0223] [Aspect 5] the protruding member has a first end and a second end along the central axis; In the protrusion member in the reference posture, a straight line connecting the center of the first end in the width direction and the center of the second end in the width direction is parallel to the central axis. 5. The piping system of embodiment 4.

[0224] [Aspect 6] The cross section of the flow path is circular. 6. The piping system according to claim 4 or 5.

[0225] Aspects 2, 3, 5, and 6 are optional elements and are not required. [Industrial Applicability]

[0226] The present disclosure is applicable to a piping system, particularly to a piping system including an elbow. [Explanation of symbols]

[0227] 1, 1A~1G Piping System 2b Inlet 3,3H vertical pipe 3a Upstream end 3b Downstream end 4 horizontal pipe 4a Upstream end 4b Downstream end 6-1~6-4,6H Protruding parts 6a 1st end 6b 2nd end 6c top 12 Piping 51 First Elbow 52 Second Elbow 110 Cheese 110a First socket 110b Second socket 110c 3rd socket 112b 2nd inlet 130 Increaser 130a First socket 130b Second socket 131 Second vertical pipe 140 Third Elbow 141 Piping 142 2nd horizontal pipe 143c outlet 1432a aperture 150a bottom wall 151 Piping 160a bottom wall 160b 1st opening 160c 2nd opening 164,164G Cheese 164a First socket 164b Second socket 164c Third underbite

Claims

1. A piping system forming a flow path, Horizontal pipe and Vertical pipe and an elbow having a first socket into which an end of the horizontal pipe is inserted, a second socket into which an end of the vertical pipe is inserted, and an inner corner portion between the first socket and the second socket; a protruding member disposed on an inner peripheral side of the elbow at the end of the horizontal pipe or the end of the vertical pipe so as to partially reduce a flow path cross-sectional area of ​​the flow path, The protrusion member has a first end and a second end in a longitudinal direction, the first end is positioned toward the corner of the elbow, and the distance between the first end and the corner is greater than or equal to 0 mm and less than or equal to 20 mm.

2. When the diameters of the horizontal pipe and the vertical pipe are each less than 75 mm, the distance is 3 mm or less; When the pipe diameters of the horizontal pipe and the vertical pipe are equal to or greater than 75 mm and less than 100 mm, the distance is equal to or less than 5 mm; When the diameters of the horizontal pipe and the vertical pipe are equal to or greater than 100 mm and less than 125 mm, the distance is equal to or less than 10 mm; The piping system according to claim 1 , wherein when the horizontal pipe and the vertical pipe each have a pipe diameter of 125 mm or more, the distance is 20 mm or less.

3. The piping system according to claim 1 , wherein the cross section of the flow path is circular or rectangular.

4. A piping system forming a flow path, Horizontal pipe and Vertical pipe and an elbow having a first socket into which the end of the horizontal pipe is inserted and a second socket into which the end of the vertical pipe is inserted; a protruding member disposed on an inner peripheral side of the elbow at the end of the horizontal pipe or the end of the vertical pipe so as to partially reduce a flow path cross-sectional area of ​​the flow path, A piping system, wherein the rotation angle of the protrusion member around the central axis of the horizontal pipe or the vertical pipe on which the protrusion member is arranged is greater than or equal to 0 degrees and less than or equal to 10 degrees with respect to a reference attitude.

5. The protruding member has a first end and a second end along the central axis, The piping system according to claim 4 , wherein, in the protruding member in the reference position, a straight line connecting a center of the first end in the width direction and a center of the second end in the width direction is parallel to the central axis.

6. The piping system of claim 4 , wherein the cross section of the flow path is circular.

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