Rainwater drainage system
The rainwater drainage system addresses blockage issues by using a sprinkler pipe with controlled outlet angles and partially blocked ends, ensuring efficient and controlled drainage without pressure loss or splashing.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- PANASONIC HOUSING SOLUTIONS CO LTD
- Filing Date
- 2026-04-24
- Publication Date
- 2026-06-25
AI Technical Summary
Existing rainwater drainage systems face issues with excessive blockage at the terminal of the diffuser pipe due to foreign matter accumulation, leading to inefficiencies and potential splashing of water.
A rainwater drainage system featuring a sprinkler pipe connected via an elbow, with controlled outlet angles and partially blocked ends to manage flow rates and prevent blockage, ensuring efficient drainage without pressure loss.
Prevents excessive blockage and splashing, maintaining efficient drainage performance across varying flow rates while minimizing pressure loss and foreign matter accumulation.
Smart Images
Figure 2026105134000001_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to a rainwater drainage system including a diffuser pipe connected from a downspout via an elbow.
Background Art
[0002] Conventionally, as described in Patent Document 1, the lower end of a downspout extending downward from the upper roof of a building is disposed above the lower roof, and a drainage member for diffusing and draining rainwater to the lower roof is provided at the lower end of the downspout. The drainage member has a downspout connection portion provided at the upper part of one end of a horizontally long rectangular parallelepiped-shaped container, and drainage holes, which are a plurality of rectangular holes, are formed in the front surface portion or the lower surface portion or both of them.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] A configuration in which a diffuser pipe extending horizontally via an elbow is connected to the lower end of a downspout from an upper roof to a lower roof such as a lower floor roof, and drainage holes are formed at a plurality of positions in the longitudinal direction of the diffuser pipe is conceivable. In this configuration, rainwater can be drained downward from the lower roof through a plurality of drainage holes of the diffuser pipe. The drained rainwater is collected in a eaves gutter attached near the eaves end of the lower roof, and can be drained downward from a downspout connected to the eaves gutter.
[0005] In the configuration described in Patent Document 1, since the terminal located at the downstream end in the flow direction of the drainage member is blocked, foreign matter flowing in from the upstream may stay at this terminal.
[0006] Therefore, an object of the present disclosure is to provide a rainwater drainage system capable of preventing the adverse effects caused by excessive blockage of the terminal of the diffuser pipe. [Means for solving the problem]
[0007] The rainwater drainage system according to this disclosure is a rainwater drainage system comprising a sprinkler pipe connected from a downpipe via a first elbow, wherein the sprinkler pipe includes a sprinkler pipe body extending in a straight line and a second elbow connected to the end of the sprinkler pipe body and bent at approximately 90 degrees, the sprinkler pipe has at least one opening facing downward, and the outlet angle θ1 of the sprinkler pipe opening is in the range of 0 degrees to 60 degrees toward the front, with θ1 = 0 degrees being the vertically downward direction, in the rainwater drainage system. [Effects of the Invention]
[0008] According to one aspect of the rainwater drainage system of this disclosure, it is possible to prevent problems caused by excessive blockage at the end of a sprinkler pipe. [Brief explanation of the drawing]
[0009] [Figure 1] This is a schematic perspective view showing a portion of a building in which the rainwater drainage system of the embodiment is installed. [Figure 2] This is an enlarged perspective view of section A in Figure 1. [Figure 3] Figure 2 is a schematic diagram of the sprinkler pipe viewed from above. [Figure 4] Figure 3 is a cross-sectional view of BB. [Figure 5] This is a view from arrow C in Figure 3. [Figure 6] In this embodiment, the view is from the perspective of arrow D in Figure 3, showing the elbow end. [Figure 7] This figure corresponds to Figure 3, which shows a watering pipe in a comparative example. [Figure 8] This figure corresponds to Figure 6, showing the elbow termination of the first example of another embodiment. [Figure 9] This figure corresponds to Figure 6, showing a second example of an elbow termination in an alternative embodiment. [Figure 10] This is a schematic diagram showing another example of a rainwater drainage system according to the embodiment. [Figure 11]Figure (a) corresponds to Figure 3 in a rainwater drainage system of another embodiment, and Figure (b) shows part E of (a) viewed in the longitudinal direction of the sprinkler pipe of (a). [Modes for carrying out the invention]
[0010] Hereinafter, embodiments of the rainwater drainage system according to this disclosure will be described with reference to the drawings. Note that if multiple embodiments or modifications are included below, it is intended from the outset that new embodiments may be constructed by appropriately combining their characteristic features. The shapes, arrangements, numbers, materials, etc., described below are illustrative examples for explanatory purposes and can be appropriately changed according to the specifications of the rainwater drainage system. In the following drawings, equivalent elements will be denoted by the same reference numerals.
[0011] Embodiments will be described using Figures 1 to 6. Figure 1 is a schematic perspective view showing a part of a building 100 in which the rainwater drainage system 1 of the embodiment is installed. The building 100 in which the rainwater drainage system 1 is installed includes an entrance door (not shown), an overhang 103 that protrudes from near the wall surface 101 above the windows on the first floor, a lower roof 104 which is above the overhang 103, and a main roof 105 which is above the lower roof 104. The main roof 105, the lower roof 104, and the overhang 103 are each formed of folded plate roofing with a corrugated cross-section. The upper surfaces of the main roof 105 and the lower roof 104 are inclined downward toward the eaves, which are the front ends. On the other hand, the upper surface of the overhang 103 is inclined upward toward the eaves. For example, the overhang 103 is suspended and supported by a support member 102 fixed near the corner of the wall surface 101 of the building so as to maintain its inclination. A canopy gutter 14, described later, is attached to the wall surface 101, and the lower end of the canopy 103 is close to the upper end opening of the canopy gutter 14.
[0012] The rainwater drainage system 1 consists of an upper eaves gutter 10 installed at the eaves of the main roof 105, a lower roof eaves gutter 12 installed at the eaves of the lower roof 104, and a canopy gutter 14 installed horizontally along the wall surface 101 near the wall surface 101 below the lower roof eaves gutter 12.
[0013] The rainwater drainage system 1 further includes an upper drain pipe 20 provided between the upper eaves gutter 10 and the lower floor 104, and a lower drain pipe 40 provided between the lower floor eaves gutter 12 and the eaves 103. The upper drain pipe 20 is connected to the lower side of the first vertical pipe 15 via the first elbow 16 from the first vertical pipe 15. The upper end of the first vertical pipe 15 is connected to the upper eaves gutter 10 via a first drainage drain (not shown). Specifically, an opening (not shown) is formed in the bottom plate portion of the upper eaves gutter 10, and the first drainage drain is attached to the opening. The upper end portion of the first vertical pipe 15 is attached to the lower side portion of the first drainage drain.
[0014] The lower drain pipe 40 is connected to the lower side of the second vertical pipe 17 via the first elbow 18 from the second vertical pipe 17. The upper end of the second vertical pipe 17 is connected to the lower floor eaves gutter 12 via a second drainage drain (not shown). Specifically, an opening (not shown) is formed in the bottom plate portion of the lower floor eaves gutter 12, and the second drainage drain is attached to the opening. The upper end portion of the second vertical pipe 17 is attached to the lower side portion of the second drainage drain. The upper end of the third vertical pipe 19 is connected to the eaves gutter 14 via a third drainage drain (not shown). Specifically, an opening (not shown) is formed in the bottom plate portion of the eaves gutter 14, and the third drainage drain is attached to the opening. The upper end portion of the third vertical pipe 19 is attached to the lower side portion of the third drainage drain. Each of the vertical pipes 15, 17, 19 is arranged along the vertical direction. The first drainage drain, the second drainage drain, and the third drainage drain may have a configuration that induces a siphon phenomenon like the drainage drain 61 used in the configuration of another example described using FIG. 10 to be described later, or may have a configuration that does not have a function of inducing a siphon phenomenon. Each of the first elbows 16, 18 is bent at approximately 90 degrees. As a result, each of the drain pipes 20, 40 extends horizontally along the wall surfaces 106, 101 close to them. The upper drain pipe 20 drains water onto the upper surface of the lower floor 104. The lower drain pipe 40 drains water onto the upper surface of the eaves 103. The structures of each of the drain pipes 20, 40 will be described in detail later.
[0015] The rainwater that falls on the large roof 105 is introduced from the upper eaves gutter 10 to the first vertical gutter 15, and after flowing down the first vertical gutter 15, it is sent to the upper drain pipe 20 through the first elbow 16. Note that the roof above the lower floor 104 is not limited to the large roof 105 including the folded-plate roof, and may also be a roof other than the large roof such as an upper-floor lower roof or a roof with a balcony function.
[0016] In the upper drain pipe 20, rainwater is drained onto the upper surface of the lower floor 104 from the plurality of opening holes 22 and the opening 25 at the end 24. The rainwater flows on the lower floor 104 toward the eaves tip and is sent to the lower eaves gutter 12. The rainwater sent to the lower eaves gutter 12 is sent from the second vertical gutter 17 to the lower drain pipe 40 through the first elbow 18. In the lower drain pipe 40, rainwater is drained onto the upper surface of the eaves 103 from the plurality of opening holes 42 and the opening 45 at the end 44. The rainwater flows on the eaves 103 and flows toward the eaves gutter 14 and is sent to the eaves gutter 14. The rainwater sent to the eaves gutter 14 flows down the third vertical gutter 19 and is drained downward.
[0017] The lower drain pipe 40 will be described in detail with reference to FIGS. 2 to 6. FIG. 2 is an enlarged perspective view of part A in FIG. 1. FIG. 3 is a schematic view of the lower drain pipe 40 in FIG. 2 seen from above. FIG. 4 is a cross-sectional view taken along line B-B in FIG. 3, and FIG. 5 is a view taken in the direction of arrow C in FIG. 3.
[0018] The upper drain pipe 20 is the same except that the number of the opening holes 42 and the opening holes 22 of the lower drain pipe 40 is different. Therefore, hereinafter, the structures of the respective drain pipes 20 and 40 will be mainly described by taking the lower drain pipe 40 as a representative. The lower drain pipe 40 includes a drain pipe body 41 extending linearly and a second elbow 43 connected to the end of the drain pipe body 41 and bent at approximately 90 degrees. The lower drain pipe 40 extends horizontally along the wall surface 101 and is attached to the wall surface 101 by a mounting bracket (not shown).
[0019] Multiple approximately circular openings 42 are provided facing downward at multiple positions along the longitudinal direction of the sprinkler pipe body 41. The end 44 of the second elbow 43, which is the downstream end and terminal of the lower sprinkler pipe 40, has an opening 45 at its bottom, and the area of the end 44 of the second elbow 43 is closed by 40-80% of the cross-sectional area of the pipe flow path of the cylindrical section 46 immediately before the end 44.
[0020] Furthermore, the multiple openings 42 are provided at intervals with a pitch P1 of 200 mm to 500 mm. The inner diameter of each opening 42 is 75 mm to 100 mm. Moreover, the pitch P1 of the multiple openings 42 is approximately the same as the pitch P2 of the multiple valleys of the folded plate roof facing the lower sprinkler pipe 40, or an integer multiple of the valley pitch P2. Figure 2 shows a case where the lower sprinkler pipe 40 is provided with four openings 42, and the pitch P1 of these openings 42 is approximately the same as the pitch P2 of the valleys of the folded plate roof forming the canopy 103. For example, the pitch P2 of the valleys of the folded plate roof can be 250 mm, 333 mm, or 500 mm. Alternatively, the pitch P1 of the multiple openings 42 may be made to match an integer multiple of the valley pitch, such as 2 or 3 times the length.
[0021] The sprinkler pipe body 41 can be made of rigid polyvinyl chloride pipe such as VP or VU pipes conforming to JIS standards, with nominal diameters of 75 mm, 100 mm, 125 mm, 150 mm, etc. Furthermore, only one opening can be provided for each sprinkler pipe 20, 40.
[0022] On the other hand, in the case of the upper sprinkler pipe 20 (Figure 1), three openings 22 are provided, and the pitch of these openings 22 is approximately the same as the pitch of the valleys of the folded plate roof forming the lower roof 104 opposite the upper sprinkler pipe 20, or an integer multiple of the length of the valley pitch.
[0023] As shown in Figures 3 and 4, the outlet angle θ1 of each opening 42 of the lower sprinkler pipe 40 is set with θ1 = 0 degrees vertically downward, and the opening is in the range of 0 degrees to 60 degrees toward the front side, i.e., toward the eaves away from the wall surface 101. In Figure 4, θ1m represents 60 degrees, which is the maximum angle of the outlet angle θ1.
[0024] As shown in Figures 3 and 5, the end of the second elbow 43 of the lower sprinkler pipe 40 has its central axis O1 facing forward at an outlet angle θ2 within the range of 0 to 60 degrees, with θ2 = 0 degrees vertically downward. In Figure 5, θ2m represents 60 degrees, which is the maximum angle of the outlet angle θ2.
[0025] Figure 6 is a view taken along arrow D in Figure 3, showing the end of the second elbow 43 in an embodiment. In Figure 6, the shaded area indicates the portion of the end 44 of the second elbow 43 that is blocked by the blocking portion 44a. In this example, the end 44 is covered with the blocking portion 44a from the upper end 44b downwards so as to block 40-80% of the cross-sectional area of the pipe flow path immediately preceding it. For example, the blocking portion 44a is formed by an upper semicircular portion with a radius of R mm, which is half the inner diameter of the pipe flow path immediately preceding it, and a substantially rectangular portion whose height is from the center that coincides with the central axis O1 of the end 44 to a position d mm downwards along the end surface, and a part of the end 44 is blocked by the blocking portion 44a. In this case, the opening 45 of the end 44 that is not blocked by the blocking portion 44a is formed in a shape enclosed by an arc which is the lower end of the outer shape of the circular end and a horizontal chord at the upper end of that arc. In this case, the area of the opening 45 can be determined from the radius R mm and the height d mm from the center to the top edge of the opening 45. Therefore, the area of the opening 45 is 0.2 × πR 2 (mm 2 Since the height dmm when it becomes equal to ) can be calculated, the position and shape of the blocking portion 44a can be determined.
[0026] In this example, the roof structure is formed from the rainwater drainage system 1, the lean-to 104 which is drained by the upper sprinkler pipe 20 below the upper sprinkler pipe 20, and the canopy 103 which is drained by the lower sprinkler pipe 40 below the lower sprinkler pipe 40. The pitch P1 of the multiple openings 22,42 of each sprinkler pipe 20,40 is spaced at intervals of 200 mm to 500 mm. The pitch of the multiple valleys of the folded plate roof forming the lean-to 104 and the canopy 103, or an integer multiple of the pitch, matches the pitch of the multiple openings 22,42 of the corresponding sprinkler pipes 20,40. A folded plate roof having valleys with different pitches may be used for the lean-to 104 and the canopy 103.
[0027] According to the rainwater drainage system 1 and roof structure described above, the ends 24 and 44 of each sprinkler pipe 20 and 40 are opened within an appropriate range, thereby preventing the problems caused by excessive opening and excessive blocking of the ends 24 and 44 of each sprinkler pipe 20 and 40. For example, the area of the ends 24 and 44 of the sprinkler pipes 20 and 40 is 80% or less of the cross-sectional area of the preceding pipe flow path, and is blocked except for the lower end. As a result, when draining at a normal flow rate, drainage can be performed with almost no pressure loss, and when draining at a high volume, the water flow can be suppressed by an appropriate pressure loss.
[0028] For example, the opening area of the ends 24 and 44 of the sprinkler pipes 20 and 40 basically depends on the flow rate, and in the sprinkler pipes 20 and 40 that extend horizontally, the water level approaches fullness from the bottom. As a result, in the case of a normal flow rate, which is usually said to be until the water level of the upstream downpipe reaches about 60%, drainage can be performed in each sprinkler pipe 20 and 40 with almost no pressure loss. Furthermore, if the drainage in each sprinkler pipe 20 and 40 exceeds the normal flow rate, for example, in the case of high drainage due to the siphon effect of the upstream downpipe, the water pressure is suppressed by a moderate pressure loss due to the moderate blockage of the ends 24 and 44.
[0029] Furthermore, since the area of the ends 24 and 44 of the sprinkler pipes 20 and 40 is open at the lower end by more than 20% compared to the cross-sectional area of the pipe flow path immediately preceding them, foreign matter such as sludge and fallen leaves can be discharged from the openings 25 and 45 of the ends 24 and 44, preventing foreign matter from accumulating at the ends 24 and 44. Also, since the area of the ends 24 and 44 of the sprinkler pipes 20 and 40 is closed at the upper side by more than 40% compared to the cross-sectional area of the pipe flow path immediately preceding them, the water pressure is suppressed with a more appropriate pressure loss. This prevents the amount of drainage from the ends 24 and 44 from becoming excessively large compared to the amount of drainage from the openings 22 and 42 of the sprinkler pipes 20 and 40. For this reason, as shown by the arrows marked with an X in Figure 1, it is possible to prevent rainwater from splashing out from the eaves over the eaves gutter 12 from the lower roof 104, or from splashing out from the eaves over the eaves from the canopy 103. Furthermore, the canopy 103 is not limited to a configuration that rises towards the eaves as shown in the illustration; it may also extend almost horizontally, or slope downwards towards the eaves, with a canopy gutter provided at the eaves.
[0030] Furthermore, it is more preferable that the area of the ends 24 and 44 of the sprinkler pipes 20 and 40 be blocked to 45-55% of the cross-sectional area of the pipe flow path immediately preceding them, and even more preferable that it be blocked to approximately 50%.
[0031] In Figure 3, the flow rate is schematically indicated by the thickness of the arrows inside the lower sprinkler pipe 40. In this embodiment, when draining at high drainage rates, especially at the ends 24 and 44 of the sprinkler pipes 20 and 40, drainage can be performed from the ends 24 and 44 with an appropriate pressure loss.
[0032] Figure 7 is a diagram corresponding to Figure 3, showing the lower sprinkler pipe 40a of the comparative example. In Figure 7, as in Figure 3, the flow rate is schematically indicated by the thickness of the arrows inside the lower sprinkler pipe 40a. In the comparative example shown in Figure 7, the end 47 of the lower sprinkler pipe 40a is not blocked. In the comparative example, the other configurations are the same as those of the embodiments in Figures 1 to 6. In this comparative example, as shown in Figure 7, when draining water particularly at high drainage at the end 47 of the lower sprinkler pipe 40a, the water flow from the end 47 is not suppressed, making it easier for rainwater to splash out from the eaves of the lower roof or canopy.
[0033] Furthermore, in the embodiments shown in Figures 1 to 6, the outlet angles θ1 of the openings 22 and 42 of each sprinkler pipe 20 and 40 are set to θ1 = 0 degrees vertically downward, and are open in the range of 0 to 60 degrees toward the front. Also, the ends of the second elbows 43 of each sprinkler pipe 20 and 40 have their central axis O1 facing forward at an outlet angle θ2 within the range of 0 to 60 degrees vertically downward, and are set to θ2 = 0 degrees vertically downward. On the other hand, if the outlet angles θ1 and θ2 exceed 60 degrees, the water is likely to be discharged to a position far away from each sprinkler pipe 20 and 40, which is inappropriate.
[0034] Furthermore, if the outlet angles θ1 and θ2 are 0 degrees, which is vertically downward, there is a concern about water splashing from the lean-to roof or eaves. Therefore, although it may depend on the water pressure, outlet angles θ1 and θ2 are more preferably 30 to 45 degrees, respectively.
[0035] Figure 8 is a diagram corresponding to Figure 6, showing the end portion 48 of the second elbow 43a in the first example of another embodiment. The meaning of the shaded area in Figure 8 is the same as in Figure 6. In this example, a circular opening 49 is formed at the lower end of the end portion 48, and the remaining portion is covered by a closing portion 48a. As a result, the end portion 48 is closed by 40 to 80% of the cross-sectional area of the pipe flow path immediately preceding it.
[0036] Figure 9 is a diagram corresponding to Figure 6, showing the end 50 of the second elbow 43b in a second example of another embodiment. The meaning of the shaded area in Figure 9 is the same as in Figure 6. In this example, the lower end edge 50b of the closing portion 50a of the end 50 is an arc that is convex on the upper side, and an opening 51 is formed below it. As a result, the end 50 is closed by 40 to 80% of the cross-sectional area of the pipe flow path immediately preceding it.
[0037] Figure 10 is a schematic diagram showing another example of a rainwater drainage system 1a. In this example of a rainwater drainage system 1a, a vertically long downpipe 70 is connected to the underside of a gutter 60 installed at the eaves of a roof such as a large roof, via a drain 61. Below the ground 107, a sprinkler pipe 72 is positioned with a first elbow 71 connected to the upstream side. The lower end of the downpipe 70 and the upper end of the first elbow 71 are not tightly connected. The end of the sprinkler pipe 72 is inserted into a drain pit 80. As a result, the sprinkler pipe 72 drains into the drain pit 80. The basic configuration of the sprinkler pipe 72 itself is the same as the configuration of each sprinkler pipe 20,40 in the embodiments shown in Figures 1 to 6, or Figure 7, or Figure 8. Multiple openings 73 are formed at multiple positions in the longitudinal direction of the sprinkler pipe 72. A pipe (not shown) connected to a sewer is connected to the drain pit 80.
[0038] The drainage drain 61, connected between the eaves gutter 60 and the downpipe 70, has a high drainage function. For example, the drainage drain 61 is composed of an upper drain member 62 and a lower drain member 65, and an opening (not shown) is formed in the bottom plate portion of the eaves gutter 60, to which the drainage drain 61 is attached. The upper drain member 62 and the lower drain member 65 are screw-connected to each other with the bottom plate portion of the eaves gutter 60 in between. The drainage drain 61 induces a siphon effect when a large amount of rainwater flows into the eaves gutter 60, such as during heavy rain. For this purpose, the upper drain member 62 includes vane portions 63 erected at multiple positions, for example, five positions, at approximately equal intervals in the circumferential direction on the upper surface of the flange, an upper cylindrical portion supported coaxially with the lower cylindrical portion of the drainage drain by being connected to the radially inner ends of the multiple vane portions 63, and an expanding portion connected to the upper end of the upper cylindrical portion and expanding upwards. The multiple vane sections 63 have the function of straightening the flow of rainwater that flows in from the inlet of the upper drain member 62. As a result, the rainwater is straightened and flows by the multiple vane sections 63, which induces a siphon effect.
[0039] When the flow rate of rainwater in the downpipe 70 exceeds a predetermined flow rate, the rainwater flowing down the downpipe 70 is forcefully drained downwards by the siphon effect. Specifically, when the flow rate of rainwater in the downpipe 70 exceeds a predetermined flow rate, it becomes easier for a plug to form in a part of the downpipe 70 due to the blockage of rainwater. Then, a negative pressure is created at this plug due to the difference in height, which increases the force pulling the rainwater downwards and causes a siphon effect that forcefully drains the rainwater. In addition, the drain 61 described above has multiple vanes 63 that enhance the effect of straightening the flow of rainwater, so the generation of vortices can be suppressed when rainwater flows into the inlet. This prevents air from being sucked into the downpipe 70 by vortices, so it can exhibit better siphon performance and improve drainage efficiency.
[0040] In a high-drainage system 108 including a downpipe 70, a drain 61, and a sprinkler pipe 72, excessive blockage of the end of the system 108 increases the loss in the dashed line area of Figure 10. This increases the flow path pressure loss, which reduces drainage performance. Furthermore, excessive blockage of the end of the sprinkler pipe 72 can cause clogging of foreign objects such as debris at the end. Also, excessive opening of the end of the sprinkler pipe 72 can cause rainwater to leak from the upper side of the drain basin 80.
[0041] In this example, since the end 74 of the sprinkler pipe 72 is moderately open, it is possible to prevent the problems caused by excessive opening and excessive blocking of the end 74. For example, since the end 74 is not excessively blocked, the flow pressure loss in the high drainage system 108 can be reduced, and the deterioration of drainage performance can be suppressed. Also, clogging of foreign objects at the end 74 can be suppressed. Furthermore, since the end 74 is not excessively open, rainwater leakage from the drainage manhole 80 can be prevented. In addition, water can be drained into the ground or to another drainage section connected to a sewer pipe from the multiple openings 73 of the sprinkler pipe 72.
[0042] Figure 11(a) is a diagram corresponding to Figure 3 in a rainwater drainage system of another embodiment, and Figure 11(b) is a view of part E in (a) along the longitudinal direction of the sprinkler pipe 82 in (a). In this example, no drain is provided at the end of the sprinkler pipe 82. The end 84 of the sprinkler pipe 82 is provided at one end in the longitudinal direction of the sprinkler pipe 82, and its upper side is closed by a sealing part 85, and its lower end is open by providing an opening 86 below it.
[0043] Furthermore, the area of the end 84 of the sprinkler pipe 82 is blocked by 40-80% of the cross-sectional area of the pipe flow path immediately preceding it. The sprinkler pipe 82 is used, for example, as the upper sprinkler pipe and the lower sprinkler pipe in Figure 1.
[0044] In this example, since no drain is provided at the end of the sprinkler pipe 82, the water drained from the end 84 of the sprinkler pipe 82 is drained diagonally downward as indicated by arrow α in Figure 11. Even in this case, the water pressure of the drainage can be suppressed by moderately blocking the end 84 of the sprinkler pipe 82, thereby suppressing rainwater from splashing out from the eaves of the lean-to roof or canopy. Furthermore, the accumulation of foreign matter at the end of the sprinkler pipe 82 can also be suppressed. In this example, the other configurations and operations are the same as those in Figures 1 to 6. [Explanation of Symbols]
[0045] 1,1a Rainwater drainage system, 10 Upper eaves gutter, 12 Lower eaves gutter, 14 Canopy gutter, 15 First downpipe, 16 First elbow, 17 Second downpipe, 18 First elbow, 19 Third downpipe, 20 Upper sprinkler pipe, 22 Opening hole, 24 End, 25 Opening, 21 Large diameter cylindrical section, 40,40a Lower sprinkler pipe, 41 Sprinkler pipe body, 42 Opening hole, 43,43a,43b Second elbow, 44 End, 44a Blocking section, 44b Upper end, 45 Opening, 46 Cylindrical section, 47,48 End, 48a Blocking section, 49 Opening, 50 End, 50a Blocking section, 50b Lower edge, 51 Opening, 60 Eaves gutter, 61 Drainage drain, 70 71 Downpipe, 72 First elbow, 73 Sprinkler pipe, 73 Opening, 74 End, 80 Drain manhole, 82 Sprinkler pipe, 84 End, 85 Blocking section, 86 Opening, 100 Building, 101 Wall surface, 102 Support member, 103 Eaves, 104 Lean-to roof, 105 Main roof, 106 Wall surface, 107 Ground, 108 High drainage system.
Claims
1. A rainwater drainage system comprising a sprinkler pipe connected from a downpipe via a first elbow, The sprinkler pipe includes a sprinkler pipe body that extends in a straight line and a second elbow connected to the end of the sprinkler pipe body and bent at approximately 90 degrees. The sprinkler pipe is provided with at least one opening facing downwards. The outlet angle θ1 of the opening of the sprinkler pipe is such that, with θ1 = 0 degrees vertically downward, the opening is in the range of 0 degrees to 60 degrees toward the front. Rainwater drainage system.
2. In the rainwater drainage system according to claim 1, The aforementioned outlet angle θ1 opens in the range of 30 degrees to 45 degrees toward the front. Rainwater drainage system.
3. In the rainwater drainage system according to claim 1, The end of the second elbow has its central axis facing forward at an exit angle θ2 within the range of 0 to 60 degrees, with θ2 = 0 degrees vertically downward. Rainwater drainage system.
4. In the rainwater drainage system according to claim 1, The at least one opening portion is a plurality of opening portions provided at intervals of 200 mm to 500 mm, The inner diameter of each of the aforementioned multiple openings is 75 mm to 100 mm. Rainwater drainage system.
5. In the rainwater drainage system according to any one of claims 1 to 4, The aforementioned sprinkler pipe drains water onto the upper surface of the lean-to or eaves. Rainwater drainage system.