AU2007346305B2

AU2007346305B2 - A drain arrangement

Info

Publication number: AU2007346305B2
Application number: AU2007346305A
Authority: AU
Inventors: Alex Waldron
Original assignee: WASHROOM SERVICES Ltd
Current assignee: WASHROOM SERVICES Ltd
Priority date: 2007-02-05
Filing date: 2007-02-05
Publication date: 2011-07-21
Anticipated expiration: 2027-02-05
Also published as: EP2109703A1; AU2007346305A1; WO2008096092A1

Abstract

A drain arrangement comprising a drain sleeve to define a seat for a float closure, the sleeve acting in use as a conduit for a fluid flow and the closure buoyant in the fluid flow.

Description

A Drain Arrangement The present invention relates to drain arrangements and more particularly to drain arrangements utilised with regard to' urinals and slab drains. 5 A reference herein to a patent document or other matter which is given as prior art is no to be taken as an admission that that document or matter was known or that the information it contains was part of the common general knowledge as at the priority date of any of the claims. Throughout the description of this specification the word "comprise" and variations of 10 that word, such as "comprises" and "comprising", are not intended to exclude other additives or components or integers. There is extensive use of urinals and slab drains in public buildings and sports stadia. The advantage of such urinals and slab drains is trie ability to accommodate a relatively large 15 throughput of people wishing. to urinate. Typically, a urinal or slab drain has a relatively large diameter drain aperture to accommodate relatively high service fluid flow volumes. This drain aperture advantageously must have an effective odour trap as well as ideally means to reduce liquid scaling and avoid urine lingering about surfaces of the drain aperture, particularly adjacent to its open end. 20 Previously it has been known to provide water traps either within the aperture itself through a U-bend or through a conduit path which extends below the water surface in the drain. Unfortunately, particularly with regard to the slab drains, there is limited space available in which to create such water traps and, therefore, difficulties are experienced. 25 In accordance with the present invention there is provided a drain arrangement comprising a drain sleeve for location within a drain aperture in use, the sleeve having a substantially consistent cross-section with a seat at an outlet end for a float to act as a closure for the seat, the sleeve acting in use as a conduit for a fluid flow towards the outlet end, the 30 float having buoyancy in the fluid flow, the seat projecting inwardly and shaped to centrally locate the float resting thereon with a gap between the float and an inner wall of the sleeve when there is no fluid flow to provide an odour seal under gravity at a pre-determined position relative to an outlet end of the drain aperture whereby in use fluid flows into the gap from above the seat to flood the gap until the float lifts from the seat, the float and the seat respectively shaped with the mass of the float for a particular fluid flow rate to guide the fluid flow over the float centrally below the sleeve away from upper parts of the drain aperture. 5 Typically, the drain sleeve has a cap. Possibly, the cap incorporates apertures to allow flow therethrough. Advantageously the cap incorporates a disinfectant and/or, deodorising agent for the fluid flow. 10 Ia WO 2008/096092 PCT/GB2007/000388 2 Typically, the sleeve comprises a tube. Possibly, the seat is integrally formed with the sleeve. Alternatively, the seat is provided by a constriction element secured to an end of the sleeve. 5 Possibly, the float closure comprises a ball. Alternatively, the float has a reciprocal shape to engage an opposed part of the seat. Possibly the seat is reciprocally shaped for closure with the float closure. Possibly, the float closure has an egg or pear-shaped cross-section. Normally, the float is 10 hollow. Possibly, the float, when sufficiently buoyant in the fluid flow, acts to abut the cap. Possibly, abutment with the cap facilitates release of agents from the cap into the fluid flow. 15 Possibly, the float is weighted to one side in order to bias the float towards engagement with the seat. Possibly, the float has a seal surface. 20 Possibly, the float is shaped to guide the fluid flow centrally below the sleeve. Advantageously, the sleeve is secured in a drain aperture. Most 25 advantageously, the sleeve protrudes no more than about 0.5cm beyond a bottom edge of the drain aperture. Embodiments of certain aspects of the present invention will now be described by way of example only and with reference to the accompanying 30 drawings in which: Fig. I is a schematic side illustration of a drain arrangement in accordance with first aspects of the present invention in a closed condition; WO 2008/096092 PCT/GB2007/000388 3 Fig. 2 is a schematic depiction of the arrangement depicted in Fig. 1 in an open condition; Fig. 3 is a schematic cross-section of a drain arrangement in 5 accordance with a second embodiment of certain aspects of the present invention; and Fig. 4 is a schematic cross-section of the arrangement depicted in Fig. 3 in an open condition. 10 As indicated above urinals and slab drains provide convenient facilities in large public buildings, including public houses and sports stadia. By their nature, the drain arrangements for such urinals must be able to accommodate high flow rates and, therefore, have relatively wide diameter drain apertures through which the urine flows. Such wide apertures lend themselves to 15 release of odours and may be difficult to provide with a water trap. Drain arrangements in accordance with aspects of the present invention are generally inserted into drain apertures in order to provide an odour trap as well as disinfecting and deodourising effects from release 20 blocks incorporated into the arrangement. Figs. I and 2 illustrate a first embodiment of a drain arrangement 1 in accordance with aspects of the present invention. Fig. I illustrates the arrangement I in a closed condition whilst Fig. 2 illustrates the arrangement 1 25 in an open condition when a fluid flow in the direction of arrowheads F can pass through the arrangement I into a drain 2 through a drain aperture 3. Generally, a drain sleeve 4 extends through the aperture 3 in order to present an outlet 5 through which the fluid F flows. This fluid as described above is generally substantially urine but it will also be understood periodically that the 30 drain arrangement will be flushed with a flushing fluid utilised to clean a urinal or slab drain 6 in which the arrangement 1 is set through the drain aperture 3.

WO 2008/096092 PCT/GB2007/000388 4 A float closure 7 is provided within the sleeve 4. This float closure 7 will normally be hollow or formed from material which has a specific density such that it is buoyant in the fluid flow F. In such circumstances it will be 5. understood in the flow F the float 7 will raise and fall dependent'upon the volume of fluid in the fluid flow F. The fluid flow F passes through apertures 8 in a cap portion 9 of the arrangement 1. In such circumstances, the fluid flow will initially dwell in the 10 area beneath the cap 9 above the sleeve 4 but the float closure 7 will rapidly rise in order to open a pathway around the float closure 7 for the fluid flow F. Thus, the flow F will pass through the outlet 5. As indicated above, it is important that the fluid flow F can be readily 15 accommodated by the arrangement 1. In such circumstances, the dimensions of the float closure 7, as well as the sleeve 4, will be chosen such that there is an adequate cross-section gap when the float is raised upon buoyancy within the fluid flow F to ensure that there is only acceptable constriction to the-fluid flow such that the urinal 6 does not overflow. It will 20 also be understood that a periodic flush cleaning of the urinal 6 will present a high fluid flow to the arrangement 1 and this similarly must be accommodated by the arrangement by lifting the float 7 to enable that flush fluid flow to pass between the float 7 and the inner walls of the sleeve 4 to exit through the outlet 5 into the drain 2. 25 in the embodiment depicted in Figs. 1 and 2, it will be noted that the float closure 7 is spherical and has a ball shape. In such circumstances, the float 7 is not orientational-dependent and can, therefore, swivel and rotate if necessary whilst floating on the fluid flow F. Nevertheless, in its closed 30 position depicted in Fig. I it is important that closure of the outlet 5 is achieved to act as an odour trap. Thus, the float closure 7, although air-filled, will generally have sufficient weight to seal out odours from the substantive WO 2008/096092 PCT/GB2007/000388 5 part of the drain 2. In such circumstances, parts of the float closure 7 vill, therefore, engage parts of the seat created by the outlet 5 for the float closure 7. 5 With a spherical or ball-shaped float 7, it will be understood that the contact surfaces may be relatively broad to provide an adequate closure for odour prevention. To further enhance such sealing, the surface of the float closure 7 may be rendered slightly compliant and, therefore, act as a seal 10 surface in compression with the seat formed by the outlet 5. Similarly, inner seat surfaces of the outlet 5 may be tactile or otherwise rendered for sealing contact with the float closure 7. Nevertheless, it will be appreciated that this specific seal surface interface between in the float closure 7 and/or the seat formed by the outlet 5 should not be such that there is any inhibition of float 15 lifting due to the buoyancy of the float closure 7 in the fluid flow F. A spherical or ball shape for the float closure 7 is convenient for the reasons described above and also in terms of providing predictability with respect to the available cross-section either side of the float closure 7 in the 20 sleeve 4 for fluid flow F in use. The float closure 7 will generally be of a narrower diameter than the width of the sleeve 4 in order that fluid can dwell, as described above, in an area 10 during the initial stages of fluid flow F in order that the float closure 7 will rise under its buoyancy in the fluid flow to open the outlet 5. Too narrow a gap between the float closure 7 and the inner 25 walls of the sleeve 4 may retard buoyancy lift and, therefore, create too great a dwell in fluid flow leading to overflow of fluid from the urinal 6. It will be 'understood that the arrangement I should be able to accommodate both trickle flows through normal use of the urinal 6 as well as 30 flood flows during flushing. Such wide ranging flow rates for the fluid flow F may be difficult to accommodate with a spherical or ball-shaped closure float 7. In such circumstances, as depicted in.Figs. 3 and 4, an egg- or pear- WO 2008/096092 PCT/GB2007/000388 6 shaped float member 37 may be provided. Thus, as depicted in Fig. 3, the float closure 37 closes a drain arrangement 31 through an outlet 35. As previously, a drain sleeve 34 is fitted into a -drain aperture 33 which extends 5 into a drain 32. -The arrangement 31 includes a cap 39 incorporating apertures through which a fluid flow FF passes initially to dwell in an area 40 before the buoyancy of the flow closure 37 causes it to rise in the fluid flow FF to open a passage or conduit through the arrangement 1 for the fluid flow FF into the drain 32. 10 Having a pear or egg or elongate shape, it will be understood that more alignment of the movement of the float closure 37 can be achieved and greater displacement may be possible with lower flow rates FF enabling the arrangement 31 to more appropriately open over the full range of flow rates, 15 that is to say, from trickle to flood flows during flushing. It will be understood that the angular nature of the float closure 37 will increase the available cross section for fluid flow FF with higher displacement of the float closure 37. Although described as spherical or elongate, pear or egg shapes, it will 20 be understood that other float closure shapes could be used dependent upon particular requirements. These shapes may include flat button-type or cylindrical float members. Furthermore, the float closures may have a donut shape with a central guide post upon which the float closure slides as to floats under its buoyance in the fluid flow. 25 Upward movement of the float closures 7, 37 in accordance with aspects of the present invention is generally limited by the cap 39. However, where appropriate, float closures could be provided which are trapped in order to limit the range of movement under buoyancy within the fluid flow and, 30 therefore limit the maximum cross-section for fluid flow through a drain arrangement if required. However, as indicated above, generally avoidance of overflow of the urinal is important and, therefore, maximum available cross- WO 2008/096092 PCT/GB2007/000388 7 section will be given to maximize fluid flow-through. Nevertheless, where a certain level of liquid dwell may be advantageous for cleaning purposes by careful choice of the maximum level cross-sectional areas through the 5 arrangement, it will be understood that retention of some flood flush liquid dwell may be achieved in the arrangement as well as the urinal or slab drain gutter. Limiting the gap between the float closure and the sleeve will also limit the rise of any solid debris which may enter the drain. 10 The present drain arrangements are generally utilised with regard to urinals and other sanitary drainage systems. In such circumstances, disinfectant, cleaning and deodourising agents may be utilised. It is common to provide within the cap 9, 39 a block of disinfectant, cleaning and/or deodourising material. This material will generally be washed by a flush flood 15 of water used to cleanse the urinal but will be positioned in the dome of the cap in order to limit washing by urine in normal use. Possibly, in accordance with certain aspects of the present invention, a float closure which is lifted into compressive engagement with the top of the dome of the cap of a drain arrangement may be utilised in order to stimulate release of agents under 20 flush flooding conditions. It will be understood that the forceful lifting of the float closure will compress against the dome which, if it comprises a bladder or other appropriate membrane, will be pushed by the abutment of the float closure to release agents into the flood flow for cleansing purposes. 25 It will be noted that the drain sleeve in accordance with certain aspects of the present invention is essentially a tube which is extends centrally down through the drain arrangement. In order to prevent the float closure blocking any of the apertures 8, 38 this sleeve will constrain the float closure to central portions of the arrangement. 30 It will be appreciated in accordance with aspects of the present invention that the drain sleeve incorporates a seat against which the float WO 2008/096092 PCT/GB2007/000388 8 closure acts in order to provide an odour trap and from which the float closure lifts in order to provide an opening through which the fluid flow can pass. This seat can be integrally formed with the drain sleeve during a moulding process. 5 However, integrally forming the seat with any degree of accuracy may be difficult. Alternatively, the seat which as indicated generally provides the outlet 5, 35 may be a separate constriction member secured over an end of the drain sleeve in order to confine the float closure in use. In such circumstances, when assembling a drain arrangement in accordance with the 10 present invention, the float closure may be placed in the drain sleeve either by removing the cap 9, 39 and dropping the float closure down the drain sleeve or, prior to installation, removing the constriction member to enable the float closure to be placed in the drain sleeve from that end. 15 It will be understood that the drain sleeve 4, 34, as illustrated in the drawings, will generally be secured within a drain aperture 3, 33. Typically, the drain sleeve 4, 34 will not be in direct contact with the aperture 3, 33 and other securing mechanisms will be used to provide an inference fit in the drain aperture 3, 33 to ensure robust location of the arrangement 1, 31. 20 As described above, particularly when used with regard to slab drains, there may be limited space below the aperture 33 within which to accommodate parts of the arrangement 1, 31. In such circumstances, in accordance with certain aspects of the present invention, the drain sleeve 25 and, in particular, the outlet 5, 35 is arranged such that it does not extend greater than about 0.5cm beyond the bottom opening of the aperture 3, 33. In such circumstances, any problems with respect to lack of space below the aperture 33 will be limited. 30 As indicated above, the float closure in accordance with the present invention must have sufficient buoyancy in the fluid flow to rise appropriately quickly to allow fluid flow release through the arrangement in both normal WO 2008/096092 PCT/GB2007/000388 9 operation with urine as well as flood flow for flushing. The floats will be relatively light and may be hollow plastic elements or formed from lightweight foam or plastics materials. In such circumstances, in order to ensure 5 appropriate bias or orientation with regard to the float closure, the float closure may be weighted to one side or appropriately to bring the float closure into association with the seat in order to creating a seal to act as an odour trap. Such weighting, as indicated, may also provide orientation which will then generally ensure that bands or otherwise portions of the float closure which 10 are treated to act as sealing surfaces are brought into association with the seat by the orientation created through weighting. As can be seen in Fig. 4, the seat 35 and parts 41 of the float closure 37 may be reciprocally shaped for engagement to improve sealing efficiency. 15 A further advantage with regard to using an elongate shaping, such as an egg or pear shape as depicted in Fig. 3 and 4 with regard to the float closure 37, is that the fluid flow may be guided by contact with the float 37 in order to fall or pour from a nose end 42. In such circumstances, particularly with low flow rates during normal urine action, the urine will drip centrally 20 within the drain 32 potentially reducing washing of the urine on the inner surfaces of the drain 32 and, therefore, scaling of those surfaces. It will also be understood that with regard to orientation, this nose end 42 will generally be the weighted end of the float 37 to create appropriate orientation in use. 25 It will be understood that a urinal thickness T will generally be in the order of 2cm so that the sleeve 4, 34 will generally extend only 2.5cm which achieves a relatively compact form. The seat formed by the sleeve may be conical towards an outlet end so 30 that a ball or cone shaped float closure may be used. Thus, it may again be possible to select the available gap cross-section in terms of variation with float displacement distance. The conical nature of such a seat would also WO 2008/096092 PCT/GB2007/000388 10 guide the float member back to provide an odour trap seal over the outlet when there is no flow. As shown in Fig. 3 a recess 50 may be provided at the rear of the float closure where some liquid may be retained to add weight 5 when there is no flow in order to improve sealing. As indicated above, generally the drain arrangement in accordance with the present invention, will be made from a plastic material of sufficient durability to withstand use within the harsh and hostile environment of a 10 urinal. As indicated above, reduction of the exposed area of a drain which is wetted with:urine reduces the amount of scale build-up and odour. Previous approaches which have utilised dip tubes have a number of problems. The 15 present arrangement provides a sleeve with float closure so that as the sleeve is shut it does not touch the reservoir of urine and so reduces the chances of bacteria climbing back up the drain to the surfaces of the urinal whether through movement along the surface or by diffusion through the air. A dip tube by its very nature presents an extra surface upon which bacteria and 20 limescale can develop. Furthermore, although a dip tube allows for a reduced surface area of the reservoir in contact with urine as the urine is presented directly below the surface of the urine reservoir, it will be understood that it does provide through the dip tube itself a pathway for odour vapours to permeate the surface. By use of a float closure in accordance with the 25 present invention, it will be appreciated that odours are almost eliminated. Finally, it will be appreciated that dip tubes may become blocked and in any event generally require more material in their manufacture. Whilst endeavouring in the foregoing specification to draw attention to 30 those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or WO 2008/096092 PCT/GB2007/000388 11 shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

1. A drain arrangement comprising a drain sleeve for location within a drain aperture in use, the sleeve having a substantially consistent cross-section with a seat at an outlet end for a float to act as a closure for the seat, the sleeve acting in use as a conduit for a fluid flow 5 towards the outlet end, the float having buoyancy in the fluid flow, the seat projecting inwardly and shaped to centrally locate the float resting thereon with a gap between the float and an inner wall of the sleeve when there is no fluid flow to provide an odour seal under gravity at a pre-determined position relative to an outlet end of the drain aperture whereby in use fluid flows into the gap from above the seat to flood the gap until the float lifts from the 10 seat, the float and the seat respectively shaped with the mass of the float for a particular fluid flow rate to guide the fluid flow over the float centrally below the sleeve away from upper parts of the drain aperture.

2. An arrangement as claimed in claim I wherein the drain sleeve has a cap.

3. An arrangement as claimed in claim 2 wherein the cap incorporates apertures to allow 15 flow there through.

4. An arrangement as claimed in claim 2 or 3 wherein the cap incorporates a disinfectant and/or deodorising agent for the fluid flow.

5. An arrangement as claimed in any one of claims I to 4 wherein the sleeve comprises a tube. 20

6. An arrangement as claimed in any one of claims I to 5 wherein the seat is integrally formed with the sleeve.

7. An arrangement as claimed in any one of claims 1 to 5 wherein the seat is provided by a constriction element secured to an end of the sleeve.

8. An arrangement as claimed in any one of claims I to 7 wherein the float closure 25 comprises a ball.

9. An arrangement as claimed in any one of claims I to 7 wherein the float has a reciprocal shape to engage an opposed part of the seat.

10. An arrangement as claimed in claim 9 wherein the seat is reciprocally shaped for closure with the float closure. 12

11. An arrangement as claimed in claim 9 or 10 wherein the float closure has an egg or pear-shaped cross-section.

12. An arrangement as claimed in any one of claims 1 to 11 wherein the float is hollow.

13. An arrangement as claimed in any one of claims I to 12 wherein the float, when 5 sufficiently buoyant in the fluid flow, acts to abut the cap.

14. An arrangement as claimed in claim 13 wherein abutment with the cap facilitates release of agents from the cap into the fluid flow.

15. An arrangement as claimed in any one of claims I to 14 wherein the float is weighted to one side in order to bias the float towards engagement with the seat 10

16. An arrangement as claimed in any one of claims 1 to 16 wherein the float has a seal surface.

17. An arrangement as claimed in any one of claims I to 16 wherein the sleeve is secured in a drain aperture.

18. An arrangement as claimed in claim 17 wherein the sleeve protrudes no more than 15 about 0.5cm beyond a bottom edge of the drain aperture.

19 A drain arrangement substantially as hereinbefore described with reference to Figures I and 2 or 3 and 4 of the accompanying drawings.

20 13