WO2012076855A1

WO2012076855A1 - Automatically operating flood barrier

Info

Publication number: WO2012076855A1
Application number: PCT/GB2011/001709
Authority: WO
Inventors: Geoffrey Evans
Original assignee: Geoffrey Evans
Priority date: 2010-12-09
Filing date: 2011-12-09
Publication date: 2012-06-14
Also published as: GB201020823D0; GB2486245B; GB2486245A

Abstract

A fluid barrier consisting of a buoyant member which is positioned in front of an aperture in a wall of a structure and adapted to rotate about a horizontal axis under the influence of asymmetric buoyancy forces and reach a vertical position closing off the aperture before flood water or other errant fluids reaches the level of a threshold to the aperture.

Description

AUTOMATICALLY OPERATING FLOOD BARRIER

The present invention relates to devices, hereinafter referred to as flood barriers, for preventing the passage of water or other fluids through apertures in structures and more specifically, to flood barriers which operate automatically in response to flood conditions developing in the vicinity of a structure.

Flood barriers which close automatically in response to the development of flood conditions in the vicinity of structures are known and a particular device is disclosed in patent specification US 6,623,209. The device disclosed in this specification consists of a buoyant flat member which is housed in a well in front of an aperture such as a doorway in a structure which is to be protected against the ingress of flood water and is pivoted so as to rotate about a horizontal axis adjacent the wall of the structure. A grid enables water to enter the well so as to cause it to rise from a horizontal position and rotate about the axis as the depth of the water increases, until the buoyant member abuts the wall of the structure, so closing off the aperture in the wall of the structure. The buoyant member rotates between two projecting side walls and is provided with seals which bear against the side walls, so as to prevent water from passing around the sides of the buoyant member as it rises into the closed position against the wall of the structure concerned. The surfaces of the wall surrounding the aperture, against which the buoyant member bears when in the closed position, are provided with face seals. Automatic opening of the flood barrier as flood water levels fall can be provided by arranging for the face seals to be slightly out of the vertical plane, inclining towards the buoyant member. This device has a number of disadvantages;

1) The presence of the projecting side walls could be an inconvenience.

2) Leakage of water between the sides of the buoyant member and the side walls as it rises into the closed position might occur.

3) In order to obtain an effective seal, the inward-facing surfaces of the side walls have to be smooth and the seals have to bear against the side walls with appreciable force. The frictional forces generated between the seals on the sides of the buoyant member and the side wall could hinder the operation of the flood barrier, particularly as the seals age.

4) Although the initial movement of the buoyant member from the horizontal position is in response to the action of buoyancy forces generated by water gaining access to the underside of the buoyant member, as it rises from the horizontal position these forces decrease in relation to hydrostatic forces generated by rising water levels in the space between the buoyant member and the side walls between which it moves, and

5) In the event of rapidly rising flood water levels, the barrier may be overwhelmed before it has time to rise to the closed position.

It is an object of the present invention to provide an automatically operating flood barrier which does not suffer from the above disadvantages.

According to the present invention there is provided a fluid barrier adapted to prevent the passage of water or other errant fluids through an aperture in a wall of a structure, comprising a buoyant member having a contact surface which conforms with that of the portion of the wall surrounding the aperture, means for positioning the buoyant member on the side of the portion of the wall of the structure surrounding the aperture from which it is anticipated that flood water or other errant fluids will approach the aperture the buoyant member being mounted so as to be capable of rotating about a horizontal axis adjacent and parallel to the aperture, means for allowing the water or other errant fluids access to the underside of the buoyant member and means for providing a fluid tight seal between the buoyant member and the portion of the structure surrounding the aperture when the buoyant member is in its operative position, wherein the buoyant member has an asymmetric cross-section such that the portion of the buoyant member adjacent the axis of rotation is thicker than that further from the axis of rotation and the axis of rotation of the buoyant member is closer to the surface of the buoyant member which is adapted to contact the portion of the wall which surrounds the aperture than to the opposite surface of the buoyant member and below a threshold to the aperture such that buoyancy forces cause the buoyant member to rise, rotate and contact the portion of the wall of the structure before the level of the flood water or other errant fluids reaches the said threshold.

Preferably the buoyant member has a cross-section consisting of two substantially rectangular sections, one being wider than the other joined by a trapezoidal section, so arranged as to present one side which is continuous. This side forms the contact surface of the fluid barrier. The axis of rotation of the buoyant member is positioned at the lower corner of the wider section of the buoyant member nearer the contact surface thereof. The invention will now be described, by way of example only, with reference to the accompanying drawings, in which :-

Figure 1 is a pictorial view of a single panel fluid barrier embodying the invention,

Figure 2 is a side view of the embodiment of the invention shown in Figure 1, Figure 3 is a cross-section of a component of a second embodiment of the invention and

Figure 4 is a sectional view of another embodiment of the invention.

Referring to Figure 1 of the drawings, an automatically operating flood barrier 100 is shown positioned in front of an aperture 101 in a wall 102 of a structure which is to be protected against the ingress of flood water. The flood barrier 100 consists of a first component 103, which is so shaped as to have an aperture 104 which is similar to the aperture 101 in the wall 102 of the structure and a second component 105, which is made of a rigid and buoyant material and which is mounted in brackets 106, which are attached to the first component 103 of the flood barrier 104, so as to be capable of rotation about a horizontal axis 107 towards the first component 103 of the flood barrier 100. Either, or both, of the surfaces of the components, 103, 105 of the flood barrier 100 which are brought into contact when the flood barrier 100 is in its closed position can be provided with a seal so as to render the flood barrier 100 water tight when closed. As shown in the drawings, such a seal 108 is located on the outward facing surface 109 of the first component 103 of the flood barrier 100. The flood barrier 100 is attached to the wall 102 in a watertight fashion with the axis of rotation 107 of the second component 105 of the flood barrier 100 below a threshold 110 of the aperture 101 in the wall 101.

Referring specifically to Figure 2 of the drawings, the second component 105 of the flood barrier 100 has a cross-section which consists of two rectangular sections 201, 202 and a trapezoidal section 203. The rectangular section 201 of the second component 105 of the flood barrier 100 is wider than the section 202 and the axis of rotation 107 of the second component 105 of the flood barrier 100 is positioned in the upper left hand corner of the section 201 of the second component 105 of the flood barrier 100, as shown in figure 2 of the drawings. That corner of the section 201 of the second component 105 of the flood barrier 100 is rounded off so as enable the second component 105 of the flood barrier 100 to rotate about the axis 107 until it comes into contact with the outward facing surface of the first component 103 of the flood barrier 100.

In use, as flood water approaches the wall 102 of the structure, the narrower section 202 of the second component 105 of the flood barrier 100 enables the flood water to gain access to the underside of the second component 105 of the flood barrier 100, which being buoyant, begins to rise from its initial horizontal position and rotate in an anti-clockwise fashion towards the first component 103 of the flood barrier 100. This initial movement is augmented by thrust forces acting on the sloping surface of the trapezoidal section 203 of the second component 105 of the flood barrier 100. As the flood water gains access to the underside of the wider section 201 of the second component 105 of the flood barrier 100, so the buoyancy forces increase. The asymmetric positioning of the axis 107 of rotation of the second component 105 Of the flood barrier causes an increasing turning moment to be generated, which causes the second component 105 of the flood barrier 100 to rotate to a vertical position abutting the outward 5 facing surface 109 of the first component 103 of the flood barrier 100 before the flood water level reaches the threshold 110 of the aperture 101 in the wall 102 of the structure. As the second component 105 of the flood barrier 100 approaches its operative position against the outward facing surface 109 of the first component 103 of the flood barrier 100, hydrostatic forces come into effect on the under o surfaces of the second component 105 of the flood barrier 100 causing it to rotate quickly into position. These hydrostatic forces also increase the pressure on the seal 108, so also increasing its effectiveness.

As flood water levels drop, so the hydrostatic and buoyancy forces acting on the 5 second component 105 of the flood barrier 100 decrease, until a point is reached at which gravitational forces arising from the asymmetric cross-section and positioning of the axis of rotation 107 of the second component 105 overcome the hydrostatic and buoyancy forces and the flood barrier 100 opens automatically. As described, the flood barrier 100 is single unit, but the sides of the front surface of the second component 105 of the flood barrier can be provided with suitable rebates and seals so that each unit can be used as a module of a longer barrier. A cross-section of such a second component 105 of the flood barrier 100 is shown in Figure 3 of the drawings.

⁵ Referring to Figure 3 of the drawings, the front surface of the second component 105 of the flood barrier 100 has an outward facing rebate 301 down one longitudinal side and a rearward facing rebate 302 down the other longitudinal side, so that adjacent second components 105 of a succession of flood barriers 100 can be overlapped. The rearward facing rebate 302 is provided with a seal 303 so I Q as to make the overlap between the second components of adjacent flood barriers 100 water tight. Alternatively, the outward facing rebate 301 can be provided with the seal 303.

Figure 4 is a sectional view of another embodiment of the invention. Those parts 1⁵ which are in common with the first embodiment of the invention have the same reference numerals. Referring to Figure 4, the second component 105 of the flood barrier 100 is contained within a tray 401, which forms a housing surrounding the second component 105 of the flood barrier 100. The mounting brackets 106 for the second component 105 of the flood barrier 100 are attached the rear wall 402 0 of the tray 401. The tray 401 projects beyond the end of the second component 105 of the flood barrier 100 when it is in the lowered position and is provided with a grid 403 which enables flood water to gain initial access to the underside of the second component 105 of the flood barrier 100 when it is in its lowered position. The tray 401 is provided with an orifice 403, which enables the tray 401 to be connected to a drainage system. As shown in Figure 4, the tray 401 is an integral part of the first component 103 of the flood barrier 100 and the orifice 403 is in a side wall of the tray 401. Neither of these features is an essential integer of the invention, the tray 401 can be separate from the first component 103 of the flood barrier 100 and the orifice 403 can be situated in the base of the tray 401.

The invention has been described with specific reference to water floods, but it is equally applicable to other fluids, including slurries. The use of the word threshold does not imply that the invention can be used in relation to doorways only. The invention is equally applicable to any aperture in any structure which needs to be protected against floods. In the case of windows, the word threshold is to be construed as including window sills.

Claims

1. A fluid barrier adapted to prevent the passage of water or other fluids through an aperture in a wall of a structure, comprising a buoyant member having a contact surface which conforms with that of that portion of the wall surrounding the aperture, means for positioning the buoyant member on the side of the portion of the wall from which it is anticipated that flood water or other errant fluids will approach the aperture, the buoyant member being so mounted as to be capable of rotating about a horizontal axis adjacent and parallel to the aperture, means for allowing the flood water or other fluids access to the underside of the buoyant member and means for providing a fluid tight seal between the buoyant member and the portion of the wall of the structure surrounding the aperture when the buoyant member is in its operative position, wherein the buoyant member has an asymmetrical cross-section such that the portion of the buoyant member adjacent the axis of rotation is thicker than that further from the axis of rotation and the axis of rotation of the buoyant member is closer to the surface of the buoyant member which is adapted to contact a surface which surrounds the aperture in the portion of the wall than to the opposite surface of the buoyant member and below a threshold to the aperture such that buoyancy forces cause the buoyant member to rise, rotate and contact the surface which surrounds the aperture before the level of the flood water or other fluids reaches the threshold of the aperture.

2. A flood barrier according to claim 1 wherein the means for positioning the fluid barrier on the side of the wall from which the flood water or other errant fluids will approach the aperture comprises a frame having a recessed portion of at least the same width as the aperture in the wall of the structure and adapted to be attached to the wall of the structure without obstructing the aperture in the wall of the structure, the frame having a substantially planar contact surface for the buoyant member and two mounting brackets between which the buoyant member is able to rotate.

3. A fluid barrier according to claim 1 or claim 2 wherein the buoyant member has a cross-section consisting of two substantially rectangular sections, one being wider than the other, joined by a trapezoidal section so arranged as to present one side which is continuous, the said continuous surface providing a contact surface corresponding to that surrounding the aperture, means for enabling the buoyant member to rotate about an axis which is situated at the corner of the wider section of the buoyant member formed by the junction of the said contact surface and a base surface of the wider section of the buoyant member.

4. A fluid barrier according to Claiml, Claim 2 or Claim 3 wherein the contact surface of the buoyant member is adapted to enable individual flood barrier units to be coupled together to form a wider flood barrier.

5. A fluid barrier according to Claim 4 wherein the contact surface of the buoyant member has an outward facing rebate along one longitudinal edge and a rearward facing rebate along the opposite edge longitudinal edge such that the buoyant members of adjacent flood barriers overlap, either the outward or rearward facing surfaces of the rebates being provided with a sealing member.

6. A fluid barrier substantially as hereinbefore described and with reference to the accompanying drawings.