US20090065071A1 - Emergency drain for dewatering an area - Google Patents

Emergency drain for dewatering an area Download PDF

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Publication number
US20090065071A1
US20090065071A1 US12/202,678 US20267808A US2009065071A1 US 20090065071 A1 US20090065071 A1 US 20090065071A1 US 20267808 A US20267808 A US 20267808A US 2009065071 A1 US2009065071 A1 US 2009065071A1
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US
United States
Prior art keywords
weir
emergency drain
drain according
discharge opening
top wall
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US12/202,678
Other languages
English (en)
Inventor
Wolfgang Vahlbrauk
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of US20090065071A1 publication Critical patent/US20090065071A1/en
Abandoned legal-status Critical Current

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Classifications

    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04D—ROOF COVERINGS; SKY-LIGHTS; GUTTERS; ROOF-WORKING TOOLS
    • E04D13/00—Special arrangements or devices in connection with roof coverings; Protection against birds; Roof drainage ; Sky-lights
    • E04D13/04—Roof drainage; Drainage fittings in flat roofs, balconies or the like
    • E04D13/0404—Drainage on the roof surface
    • E04D13/0409—Drainage outlets, e.g. gullies
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04D—ROOF COVERINGS; SKY-LIGHTS; GUTTERS; ROOF-WORKING TOOLS
    • E04D13/00—Special arrangements or devices in connection with roof coverings; Protection against birds; Roof drainage ; Sky-lights
    • E04D13/04—Roof drainage; Drainage fittings in flat roofs, balconies or the like
    • E04D13/0404—Drainage on the roof surface
    • E04D13/0409—Drainage outlets, e.g. gullies
    • E04D2013/0422—Drainage outlets, e.g. gullies for draining water above the roof level, e.g. gullies with overflow ports
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04D—ROOF COVERINGS; SKY-LIGHTS; GUTTERS; ROOF-WORKING TOOLS
    • E04D13/00—Special arrangements or devices in connection with roof coverings; Protection against birds; Roof drainage ; Sky-lights
    • E04D13/04—Roof drainage; Drainage fittings in flat roofs, balconies or the like
    • E04D13/0404—Drainage on the roof surface
    • E04D13/0409—Drainage outlets, e.g. gullies
    • E04D2013/0427—Drainage outlets, e.g. gullies with means for controlling the flow in the outlet
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/6851—With casing, support, protector or static constructional installations
    • Y10T137/6966—Static constructional installations
    • Y10T137/6969—Buildings

Definitions

  • the invention relates to an emergency drain for dewatering an area accumulating water via a discharge opening, with which water dammed up above a minimum height can be led away, having a weir for damming up the water up to the minimum dammed height and a top wall arranged at a distance from the discharge opening to prevent air being sucked into a vortex forming in the discharge opening, the weir being arranged around the discharge opening, and the top wall, as seen from the discharge opening, extending as far as the other side of the weir.
  • Emergency drains of this type are used in particular for dewatering roof areas.
  • the function of the emergency drains is to function as a supplementary system for normal roof dewatering. With normal roof dewatering, the water is led away from the water-impermeable area.
  • the dimensioning of the drainage system which is to say in particular of a drainpipe, and also the number of drains for the size of a predefined area are determined in such a way that specific drainage performances can be implemented. If this drainage performance can no longer be ensured, for example because the discharge openings of the normal dewatering system permit only a reduced drainage performance—or in the extreme case no drainage at all—as a result of dirt, leaves or the like, the water rises on the roof area.
  • the emergency drains have the function of serving to limit the accumulated water height on an area to be dewatered, in that when a minimum dammed height on the area is exceeded, the emergency drain becomes effective with a high drainage performance, which means that a further, greater rise in the accumulated water height on the area is avoided.
  • the emergency drains are needed only infrequently, so that the risk of blockage by dirt or the like is virtually ruled out.
  • An emergency drain therefore includes a weir which, in the normal case, which is to say when the dammed height of the water on the area to be dewatered falls below a minimum, prevents the water being fed to the discharge opening of the emergency drain.
  • the weir can be formed in a simple way by the drainpipe projecting by the minimum dammed height above the level of the area to be dewatered.
  • an appropriate ring, formed by a pipe section can also be arranged with a radial spacing as seen from the center of the discharge opening.
  • the space closed off in an airtight manner is closed off at the top by a top wall which, moreover, prevents air being drawn into a discharge vortex during the pressure flow but also prevents it during a preceding non-pressure flow.
  • the weir can be located inside or outside the housing and in particular also formed by the drainpipe being lengthened upward, a funnel-like widening of the drainpipe in order to form the weir also being described.
  • the weirs are normally composed of sections of pipe with a relatively thin wall, over the upper edge of which the water accumulated above the minimum dammed height flows.
  • the known emergency drains can be designed for the necessary drainage performances, they produce a considerable intensity of noise, in particular when a pressure flow begins.
  • the present invention is based on the object of improving an emergency drain of the type mentioned at the beginning with regard to its drainage performance and the development of noise.
  • an emergency drain of the type mentioned at the beginning is characterized in that the weir has a cross section which, at the base of the weir resting on the area, is provided in the flow direction with a substantially greater width than at the highest point of the weir over which the water flows.
  • the design of the weir for the known emergency drains has hitherto not been assigned any substantial importance. However, during the use of the emergency drain, the water to be led away flows over the weir.
  • the present invention is based on the finding that the weir has a substantial influence on the flow of the water flowing away through the discharge opening and that, by means of a design of the weir which is more beneficial in terms of flow, the flow of the water flowing away can be improved with regard to the outflow performance and the development of noise.
  • this is achieved by the water on the side flowing toward the weir and/or on the side flowing away being guided in such a way that, on the inflow side, the weir does not merely form an impediment to flow on which vortices are formed, or that, on the downstream side, the weir causes an uncontrolled fall of the water flowing over the weir over the complete height of the weir.
  • the width of the weir at the base is substantially larger than at the highest point of the weir.
  • guidance of the water to the height of the weir and/or from the height of the weir as far as the base height is effected.
  • the flanks of the weir formed in this way are designed to rise or fall continuously.
  • the effect according to the invention is also achieved, even if in a somewhat attenuated form, if the flanks have step-like height differences.
  • both flanks are provided with gradual height transitions and both contribute to the greater width of the weir at the base.
  • the discharge opening is preferably formed by a mouth opening of a drainpipe that is present in the area, so that the diameters of the drainpipe and of the discharge opening are coordinated.
  • the width of the weir at 90% of the maximum height of the weir, measured from the base is less than half the width of the weir at the base.
  • the weir has a width at half its height of less than 80% of the width at the base.
  • the weir is provided with a triangular cross section in the flow direction.
  • the weir preferably has a level rising flank and a level falling flank.
  • the weir is preferably formed with a symmetrical cross section in the flow direction.
  • the weir has an asymmetrical cross section in the flow direction with an upstream flank and a downstream flank, the two flanks having an unequal length and mean steepness.
  • the flanks can be rectilinear in cross section but also curved.
  • the upstream flank preferably has a lower mean steepness than the downstream flank.
  • flanks run rectilinearly over part of their length and merge into each other with a rounded portion at the highest point, the result is a profile of the weir which is pronounced of a levee profile but which has been developed from other points of view (breaking the force of the incoming waves).
  • flow guide webs running radially toward the center of the discharge opening are provided. These can extend over the entire height between base and top wall. Their substantial function is to prevent the formation of a circulating vortex under the top wall.
  • the weir can be circular. In a preferred embodiment, however, the weir is formed as a uniform polygon in plan view, the flow guide webs extending in the direction of the corners. Particularly preferable is the formation of the weir as a uniform hexagon in plan view.
  • the height of the weir preferably extends until it is above half the spacing, further preferably until it is above two-thirds of the spacing, between the area to be dewatered and the top wall.
  • top wall is formed as a level disk.
  • the reference to the “base” of the weir in the present application signifies a reference to the lower region of the weir, which rests on the area to be dewatered.
  • the weir does not have to have a real base but, for example, can be formed by a pressed piece of sheet metal which forms a closed ring.
  • the definition of the weir is expedient, however, if it has a flange which can be referred to as a “base”, with which it can for example be screwed to the area to be dewatered.
  • FIG. 1 shows a schematic section through a building having an emergency drain system with an emergency drain according to the invention
  • FIG. 2 shows an enlarged illustration of the emergency drain according to the invention
  • FIG. 3 shows a plan view of the emergency drain according to FIG. 2 with the top wall removed;
  • FIG. 4 shows examples of possible cross-sectional shapes of the weir of the emergency drain.
  • FIG. 1 shows, schematically, a building wall 1 and a roof structure 2 of a level roof of the building.
  • the upper side of the level roof forms the area F to be dewatered.
  • the roof is dewatered in the usual way by water drains (not illustrated here). If, because of heavy rain or a blockage of the regular water drains, a minimum dammed height H is exceeded, the function of an emergency drain device 3 begins, as illustrated schematically in FIG. 1 .
  • a drainpipe 4 opens into the area F and, in the exemplary embodiment illustrated, is led by angled pieces into the vicinity of the outer wall 1 in order there, after a certain discharge height, to be led through the outer wall to form a drain 5 on the outside of the outer wall.
  • An emergency drain device 3 is not intended to lead the water into the sewerage system in the usual way, since a main use of the emergency drain devices 3 is heavy rain, by which the sewerage system is already overloaded under certain circumstances, so that a discharge from the area F which is to be dewatered independently of the possibly overloaded sewerage system is intended to be possible. Therefore, water from an emergency drain device 3 is normally discharged freely on the outside of an outer wall 1 .
  • the drainpipe 4 With its mouth opening in the area F, the drainpipe 4 forms a discharge opening 6 .
  • a weir 7 is arranged annularly in the discharge opening 6 and, in the exemplary embodiment illustrated in FIG. 1 , has a triangular cross section.
  • a top plate 8 extends radially outward, being formed as a level plate in the exemplary embodiment illustrated.
  • the top plate 8 is arranged at a defined distance A by using spacer bolts 9 .
  • the distance A is somewhat greater than the height of the weir 7 , which height corresponds to the minimum dammed height H.
  • the minimum dammed height H is more than half, preferably more than two-thirds, of the spacing A between the area F and the underside of the top wall 8 .
  • FIG. 1 reveals that water dammed up on the area F above the minimum dammed height H, as seen from a mid-axis 10 of the discharge opening 6 , must flow radially inward under the top plate 8 and over the weir 7 in order to reach the discharge opening 6 . Since the spacing of the annular weir 7 from the mid-axis 10 is chosen to be large and corresponds to at least twice the radius of the discharge opening 6 , the necessary large flow is led away through the remaining interspace between weir 7 and the underside of the top plate 8 but in highly calmed form.
  • FIGS. 2 and 3 illustrate the emergency drain in a detailed illustration.
  • the weir 7 has the form of a regular hexagon in plan view and that flow guide webs 11 running radially and projecting into the corners of the hexagon are fitted to the top plate 8 , extending from the edge of the discharge opening 6 into the corners of the weir 7 .
  • the weir 7 has a triangular cross section with an upstream flank 12 and a downstream flank 13 .
  • the downstream flank 13 merges into a flange 14 running radially inward as far as the discharge opening 6 , which flange can be referred to as “base” and is used to fix the weir 7 to the area F by means of threaded bolts 15 .
  • the relative fixing of the top wall 8 with respect to the flange 14 is made with further spacer bolts 9 ′, with which and also with the spacer bolts 9 the top wall 8 can be fixed at a defined height relative to the area F and relative to the flange 14
  • the shape of the top wall 8 is matched to the shape of the weir 7 and extends radially outward with a uniform projection 16 over the outer edge of the weir 7 .
  • the sectional illustration of FIG. 2 reveals that the weir 7 itself is open at the bottom, that is to say is not closed off at the bottom with a “base”. The sealing of the weir 7 with respect to the area F is therefore carried out on the underside of the upstream flank 12 .
  • the triangular configuration of the weir 7 which can be seen in FIGS. 1 and 2 is to be understood as purely exemplary. Because of its ability to be produced easily, it constitutes a preferred embodiment of the invention.
  • FIG. 4 shows further exemplary embodiments which are likewise conceivable and advantageous as a cross-sectional shape for the weir 7 .
  • FIG. 4 shows three cross-sectional shapes Q 1 , Q 2 and Q 3 over which the water present flows in the flow direction S.
  • the cross-sectional shape in FIG. 4 a constitutes a semicircle.
  • the weir 7 can therefore be produced in a simple way as half a pipe.
  • the cross-sectional shapes according to FIGS. 4 b and 4 c are asymmetrical cross-sectional shapes, the cross section Q 2 having a longer upstream flank 12 ′ and a shorter—and therefore steeper—downstream flank 13 ′.
  • the two flanks are substantially rectilinear and, at the highest point of the cross-sectional shape Q 2 , merge into each other via a rounded transition piece 17 .
  • the cross-sectional shape Q 3 corresponds to the cross-sectional shape Q 2 but mirror-inverted, the upstream flank 12 ′′ being shorter and having a greater mean steepness than the downstream flank 13 ′′.
  • the two substantially level flanks 12 ′′, 13 ′′ merge into each other at the highest point of the weir 7 by means of a rounded transition piece 17 .
  • the cross-sectional shapes illustrated hitherto contain a continuous reduction in width of the cross section with increasing height, starting from the area F. This corresponds to the preferred embodiments.
  • the present invention does not rule out the case in which, in particular on the downstream flank 13 , an undercut 13 a is provided, by means of which a projecting nose 13 b is formed on the downstream flank.
  • An embodiment of this type, which results as a modification of the cross-sectional shape from FIG. 4 b is illustrated in FIG. 4 d.
  • the cross-sectional shapes illustrated are to be understood as purely exemplary. Further cross-sectional shapes can readily be found by those skilled in the art within the context of the present invention.
  • the flanks 12 , 13 , 12 ′, 13 ′, 12 ′′, 13 ′′ do not have to be formed continuously but can in each case have a large number of steps, with which the height difference from the area F to the highest point of the weir 7 is overcome.
  • the falling flank can also be formed as a vertically upright wall or even be missing entirely.
  • the weir comprises only a metal sheet for the obliquely rising flank 12 , which for example can be formed as an annular metal sheet.
  • the cross section of the weir is, for example, triangular, the falling wall being left out. No relevant difference in flow terms arises from the omission of the wall.
  • the emergency drain is formed symmetrically around the discharge opening 6
  • installation positions are conceivable in which an asymmetrical formation with respect to the mid-axis 10 of the discharge opening 6 both with respect to the weir 7 and also with respect to the top plate 8 appears to be possible and expedient.

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  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Barrages (AREA)
  • Sewage (AREA)
US12/202,678 2007-09-07 2008-09-02 Emergency drain for dewatering an area Abandoned US20090065071A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102007042527.0 2007-09-07
DE200710042527 DE102007042527A1 (de) 2007-09-07 2007-09-07 Notablauf zur Entwässerung einer Fläche

Publications (1)

Publication Number Publication Date
US20090065071A1 true US20090065071A1 (en) 2009-03-12

Family

ID=40090705

Family Applications (1)

Application Number Title Priority Date Filing Date
US12/202,678 Abandoned US20090065071A1 (en) 2007-09-07 2008-09-02 Emergency drain for dewatering an area

Country Status (6)

Country Link
US (1) US20090065071A1 (fr)
EP (1) EP2034104B1 (fr)
CN (1) CN101413327A (fr)
AT (1) ATE538270T1 (fr)
DE (1) DE102007042527A1 (fr)
RU (1) RU2008136047A (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108597022A (zh) * 2018-05-08 2018-09-28 河海大学 一种估算中小流域内河道宽度的方法
US20210317666A1 (en) * 2020-04-14 2021-10-14 Zurn Industries, Llc Roof drain
USD1124271S1 (en) 2021-12-21 2026-04-28 Zurn Water, Llc Drain body

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102587597B (zh) * 2012-03-30 2014-07-09 重庆大学 基于低影响开发思想的建筑平屋顶雨水立管安装结构及安装方法
US20150017907A1 (en) * 2013-05-22 2015-01-15 Excellent Holding Aps Cooling roof construction

Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2121220A (en) * 1936-12-18 1938-06-21 Paul Dickinson Inc Roof drain
US3321080A (en) * 1963-10-14 1967-05-23 Andrew L Pansini Leaf receiver for swimming pools
US3357561A (en) * 1965-10-15 1967-12-12 Zurn Ind Inc Roof drain
US3469698A (en) * 1967-04-05 1969-09-30 Josam Mfg Co Controlled flow drain
US3909412A (en) * 1974-07-22 1975-09-30 Johns Manville Roof drain arrangement
US5702596A (en) * 1993-12-01 1997-12-30 Geberit Technik Ag Roof water inlet
US5724777A (en) * 1995-11-17 1998-03-10 Hubbard; Richard M. Roof drain arrangement and method
US5735091A (en) * 1996-03-19 1998-04-07 National Roofing Supply, A Div. Of A.C.T. Marketing Inc. Roof drain
US20020108315A1 (en) * 2001-02-14 2002-08-15 Bridgestone/Firestone, Inc Vented roofing anchor plate
USD466199S1 (en) * 2001-11-02 2002-11-26 World Wide Sports, L.L.C. Anti-vortex safety cover for a drain
US20030141231A1 (en) * 2002-01-30 2003-07-31 Rattenbury John M. Baffle insert for drains
US20030159384A1 (en) * 2002-01-15 2003-08-28 Lawrence Warnecke Drain support plate/under-deck clamp
US6833067B2 (en) * 2000-11-17 2004-12-21 Sita Bauelemente Gmbh Device for draining flat roofs, balconies, terraces or other flat structures
US7614198B1 (en) * 2004-04-29 2009-11-10 Piskula James S Method for providing existing building flat roof with drain restrictors

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1806527C3 (de) * 1968-11-02 1978-12-21 Josam Manufacturing Co., Michigan City, Ind. (V.St.A.) Flachdachablauf
DE8507736U1 (de) * 1985-03-15 1986-07-17 Hollwich, Anton, 8132 Tutzing Dachgulli-Einbauteil
GB9302475D0 (en) * 1993-02-09 1993-03-24 Harmer Holdings Ltd High flow drains
CH691320A5 (de) * 1996-10-09 2001-06-29 Werner Nill Vorrichtung zum Einstellen der Abflussmenge und der Einstauhöhe des Regenwassers von Dächern und anderen Flächen.
DE19912012C2 (de) 1999-03-17 2003-02-06 Wolfgang Vahlbrauk Notablaufvorrichtung

Patent Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2121220A (en) * 1936-12-18 1938-06-21 Paul Dickinson Inc Roof drain
US3321080A (en) * 1963-10-14 1967-05-23 Andrew L Pansini Leaf receiver for swimming pools
US3357561A (en) * 1965-10-15 1967-12-12 Zurn Ind Inc Roof drain
US3469698A (en) * 1967-04-05 1969-09-30 Josam Mfg Co Controlled flow drain
US3909412A (en) * 1974-07-22 1975-09-30 Johns Manville Roof drain arrangement
US5702596A (en) * 1993-12-01 1997-12-30 Geberit Technik Ag Roof water inlet
US5724777A (en) * 1995-11-17 1998-03-10 Hubbard; Richard M. Roof drain arrangement and method
US5735091A (en) * 1996-03-19 1998-04-07 National Roofing Supply, A Div. Of A.C.T. Marketing Inc. Roof drain
US6833067B2 (en) * 2000-11-17 2004-12-21 Sita Bauelemente Gmbh Device for draining flat roofs, balconies, terraces or other flat structures
US20020108315A1 (en) * 2001-02-14 2002-08-15 Bridgestone/Firestone, Inc Vented roofing anchor plate
USD466199S1 (en) * 2001-11-02 2002-11-26 World Wide Sports, L.L.C. Anti-vortex safety cover for a drain
US20030159384A1 (en) * 2002-01-15 2003-08-28 Lawrence Warnecke Drain support plate/under-deck clamp
US20030141231A1 (en) * 2002-01-30 2003-07-31 Rattenbury John M. Baffle insert for drains
US7614198B1 (en) * 2004-04-29 2009-11-10 Piskula James S Method for providing existing building flat roof with drain restrictors

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108597022A (zh) * 2018-05-08 2018-09-28 河海大学 一种估算中小流域内河道宽度的方法
US20210317666A1 (en) * 2020-04-14 2021-10-14 Zurn Industries, Llc Roof drain
US12018489B2 (en) * 2020-04-14 2024-06-25 Zurn Water, Llc Domed roof drain strainer assembly
US12559945B2 (en) 2020-04-14 2026-02-24 Zurn Water, Llc Domed or raised drain inlet strainers
USD1124271S1 (en) 2021-12-21 2026-04-28 Zurn Water, Llc Drain body

Also Published As

Publication number Publication date
EP2034104B1 (fr) 2011-12-21
DE102007042527A1 (de) 2009-03-26
ATE538270T1 (de) 2012-01-15
EP2034104A3 (fr) 2010-07-21
EP2034104A2 (fr) 2009-03-11
CN101413327A (zh) 2009-04-22
RU2008136047A (ru) 2010-03-10

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