GB2297769A

GB2297769A - Storm drain overflow control apparatus

Info

Publication number: GB2297769A
Application number: GB9502454A
Authority: GB
Inventors: Anthony William Collins
Original assignee: ECOLOGICAL PRODUCTS Ltd
Current assignee: ECOLOGICAL PRODUCTS Ltd
Priority date: 1995-02-08
Filing date: 1995-02-08
Publication date: 1996-08-14
Anticipated expiration: 2015-02-08
Also published as: GB9502454D0; GB2297769B

Abstract

Storm drain overflow control apparatus (10) comprises cover means (14) adapted to be arranged over a storm drain and a float (16) held by the cover means (14). The float (16) is movable between an open position in which material can pass from the cover means (14) to the storm drain around the float (16), and the closed position which material is prevented from passing around the float (16). The float (16) defines a conduit (20) therethrough, whereby when the float (16) is in the closed position, material can pass via the conduit (20) from the drain to the cover means (14).

Description

Improvements in or relating to storm drain overflow control apparatus This invention relates to storm drain overflow control apparatus.

The present apparatus for use in controlling overflow of storm drains may comprise rotary or other mechanically operated screens and require considerable amount of energy for their use.

Disadvantages of such screens are that they are expensive, difficult to maintain and can easily malfunction, and screenings need handling.

It is an object of this invention to obviate and/or mitigate the above disadvantages.

According to this invention there is provided storm drain overflow control apparatus comprising cover means adapted to be arranged over a storm drain and float means held by the cover means, the float means being movable between an open position in which material can pass from the cover means to the storm drain around the float means, and a closed position in which material is prevented from passing around the float means, and the float means defining a conduit therethrough, whereby when the float means is in the closed position material can pass via the conduit from the drain to the cover means.

In this specification the term "storm drain" is intended to include in its meaning rising mains, rising shafts or square or rectangular channels.

Preferably, the cover is provided with screening means to screen the material passed via the conduit whereby solid material having a size greater than a predetermined size is retained by the screening means and liquid may be drained away. The screening means may comprise at least one screen. The, or each, screen may be arranged around the float means. The screening means may define a plurality of apertures to allow the liquid to pass therethrough. The apertures may have a size in the range 0.25mm to lOmm, preferably 3mm to 6mm.

An advantage of the preferred embodiment is that it retains and returns screened solids to foul when a storm subsides.

The apertures may be formed as perforations in sheets of suitable material, for example a steel, preferably stainless steel or a plastics material.

Alternatively, the screens may be in the form of a mesh, a material with holes, or wedge wire and each of which may be formed of steel or a plastics material. The steel is preferably stainless steel.

The, or each, screen may diverge upwardly away from the float and may be planar, convex or concave.

Support means may be provided on the cover means to support the float when it is in the open position. The cover may have a top and at least one side and may comprise a housing extending around the top and the, or each, side. The support means may comprise a shaft extending downwardly from the top and a substantially flat plate to engage the float means.

Preferably, the cover means defines an opening in which the float is arranged, the opening being defined at the bottom of the cover. Preferably, opening is defined centrally of the bottom of the cover and the screening means may extend from the, or each, side of the cover means to the opening.

The apertures in the screening means may extend to the opening. Alternatively, the screening means may comprise a non-apertured region and an apertured region.

The non-apertured region may be provided between the opening and the apertured region.

The cover means may be provided with wash means to wash solids retained by the screening means therein back to the storm drain. The wash means may be in the form of showers provided at the top of the cover means.

The float means may comprise a first section of a size less than the size of the opening thereby to allow material to pass out of the cover around the float when the float means is in the open position. The float means may also have a second section extending downwardly from the first section and having a size greater than the size of said opening such that when the float means is in the open position the second section is below the bottom of the cover means and when the float means is in the closed position the second section engages the bottom of the cover to occlude the opening.

The second section may diverge outwardly from the first section. Floatation means may be provided on the second section whereby when liquid in the storm drain rises to the level of the float means, the float can float on said liquid. The floatation means may be in the form of a collar of a suitably buoyant material arranged around the second section.

The float means may also have a third section extending upwardly from the first section. The third section may be of such a shape and size as to divert onto the screening means material passing out of the conduit into the cover. The third section preferably diverges outwardly from the first section.

Hook means may be provided on the second section of the float means to engage solids screened by the screening means when the float means is in the closed position. The hook means may be in the form of a plurality of hooks to pull down said solids when the float is in the closed position. The hook means may be in the form of a plurality of hooks to pull down said solids when the float means moves to the open position.

Embodiments of the invention will now be described by way of example only, with reference to the accompanying drawings in which: Fig. 1 is a schematic sectional view of a storm drain overflow control apparatus showing float means in an open position; Fig. 2 is a view similar to Fig. 1 of a storm drain overflow control apparatus showing float means in a closed position; Fig. 3 is a view along the lines III-III in Fig. 2; Fig. 4 is a view similar to Fig. 3, but showing the further embodiment of a storm drain control apparatus; and Fig. 5 is a schematic perspective view of the apparatus shown in Fig. 4.

Referring to Figs. 1 to 3, there is shown storm drain control apparatus generally designated 10 which, in the embodiment shown in Figs. 1 to 3 is provided on a storm drain 12 which is in the form of a rising main having a cicular cross section.

The storm drain overflow control apparatus comprises cover means in the form of a cover 14 adapted to be arranged over the storm drain 12 and float means in the form of a float 16 which is held by the cover. The cover 14 defines-an opening 18 in which the float 16 is disposed.

The float 16 is movable from an open position, as shown in Fig. 1, to a closed position as shown in Fig. 2.

The float 16 is hollow and defines a conduit 20 therethrough, the purpose of which will be explained below.

As can be seen, the cover 14 is cylindrical in configuration with the opening 18 being defined centrally by a bottom wall 31 thereof. A support shaft 22 extends from a top wall 30 of the cover 14 and is provided at its lower end with a circular plate 24. The float 16 is provided with cross struts 26 extending across the conduit 20 between the sides thereof the support shaft 22 is received in a bearing sleeve 28 fixed to the struts 26. Thus, the plate 24 engages the underside of the cross struts 26 when the float is in the open position to support the float 16. The sleeve 28 which is packed with grease enables the float 16 to move easily up and down the shaft 22.

The bottom wall 30 is provided with inspection hatches 32. A cylindrical side wall 33 extends around the cover 14. Screening means in the form of substantially frusto-conically shaped screen 34 tapers inwardly and downwardly from the inside of the side wall 33 towards the opening 18. The screen can be planar, concave or convex.

In one embodiment, the screen 34 comprises an apertured region 36 and a non-apertured region 37, the non-apertured region 37 being arranged between the apertured region 36 and the opening 18. In another embodiment, the non-apertured region 37 is omitted and the apertured region 36 extends to the opening 18.

Adjacent the opening 18, the screens 36 extend outwardly and downwardly at the region 38 the purpose of which will be explained below. The screen 34 can be made of suitable screening material, for example a mesh or wedge wire.

The apertured region 36 defines a plurality of apertures whereby solids above a certain size are prevented from passing therethrough, but liquids and solids of a size less than the predetermined size are allowed to pass therethrough. The apertures in the region 36 are of a size in the range 3 to 6mm.

The float 16 comprises a first section 40 which is substantially cylindrical in configuration. A second section 42 below the first section 40. The second section 42 tapers outwardly from the first section 40, the taper corresponding to the inward divergence of the region 38 of the screens 36. The float 16 further comprises a third section 44 above the first section 40 the third section 44 tapers outwardly from the first section 40, as will be explained below.

During stormy periods, the storm drain 12 may fill with water and sewage material. The water and sewage material may rise up the storm drain 12 and engage the float 16.

The second section 42 is provided with a floatation collar 43 to enable the float 16 to float on water.

When the level of the water in the storm drain 12 reaches the float 16, the float 16 will float on the water by virtue of the floatation collar 43. It will be appreciated that the float 16 could be formed of an appropriate material capable of floating on water, in which case the floatation collar 43 would not be required.

Further rising of the level of the water in the storm drain 12 lifts the float 16 upwardly until the tapering edges of the section 42 engage the region 38 of the screen 34. The cover 14 is provided with a stabilizing flume 54 to ensure even floatation of the float 16. At this point, the float 16 can rise no further and the rising water must then pass upwardly through the conduit 20 in the float 16, as indicated by the dashed arrows A, until the water level reaches the top of the third section 44. The water then passes over the top of the third section 44, as indicated by the arrows B. The water pouring over the third section 44 falls onto the screen 34, which allow water to pass through and be removed via waste pipes 27 as indicated by the arrows C.Solid material which is greater in size than the size of the apertures in the screen 34 is prevented from falling through the screen 34 and follows the path indicated by the arrow D to be collected at the bottom, in the region 48.

Refering to Fig. 2A, the sides of the second section 42 may be provided with hooks 50 which serve to drag down the solid material collected in the region 48 when the float returns to the open position as will be explained below.

When the storm abates, the level of water in the storm drain 12 will fall and as it does so, the float 16 will descend until the plates 24 engages the cross-struts 26, in the position as shown in Fig. 1. In this position the solid material collected at the region 48 will descend down the storm drain 12, in the direction of the arrows E. The hooks 50, if provided, will assist in pulling down the solid material at the region 48.

The cover is provided with wash means in the form of showers 52 which can be switched on when the water reaches a predetermined level. The showers 52 then flush out the cover 14 to wash back into the storm drain the solids which had collected in the region 48. Water from the showers 52 will also pass out of the pipes 27 thus assisting in washing any material which had collected in the pipes 27. The arrows F indicate the flow of water from the showers 52, and the arrows G indicate the flow of such water along the pipes 27.

Referring to Figs. 4 and 5, there is shown a second embodiment of the invention which is generally the same as the embodiments shown in Figs. 1 to 3 with the exception that the cover 14, and the float 16, are rectangular in cross-section. The embodiment shown in Figs. 4 and 5 is suitable for use in storm drains 23 in the form of storm channels. In storm channels, a section of predetermined length is provided above the channel in which the storm drain overflow control apparatus 10 can be installed. The storm channel 56 normally carries sewage along the bottom thereof.

Various modifications can be made without departing from the scope of the invention, for example, the height of the float 16 can be varied depending upon the head of water in the sewage system. Also, the diameter, width or length of the cover 14 can be of any size to suit the size of the storm drain 12.

The cover 14 can be of any appropriate shape for example square or triangular, to suit the shape of the storm drain.

The outflow pipes 27 can be in any desired position, for example that shown in dotted lines in Fig.

3.

Whilst endeavouring in the foregoing specification to draw attention to 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 shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

Claims:

1. Storm drain overflow control apparatus comprising cover means adapted to be arranged over a storm drain and a float held by the cover means, the float being movable between an open position in which material can pass from the cover means to the storm drain around the float, and a closed position in which material is prevented from passing around the float, and the float defining a conduit therethrough, whereby when the float is in the closed position material can pass via the conduit from the drain to the cover means.

2. Apparatus according to Claim 1 wherein the cover means defines an opening in which the float is arranged, the opening being defined at the bottom of the cover means.

3. Apapratus according to Claim 2 wherein the cover means is provided with screening means to screen the material passed via the conduit whereby solid material having a size greater than a predetermined size is retained by the screening means and liquid may be drained away.

4. Apparatus according to Claim 3 wherein the opening is defined centrally of the bottom of the cover and the screening means extends from the, or each, side of the cover means to the opening.

5. Apparatus according to Claim 3 or 4 wherein the screening means comprises at least one screen, the or each, screen being arranged around the float.

6. Apparatus according to Claim 5 wherein the, or each, screen comprises an apertured region defining a plurality of apertures to allow the liquid to pass therethrough.

7. Apparatus according to Claim 6 wherein the apertures have a size in the range 0.25mm to lOmm, preferably 3mm to 6mm.

8. Apparatus according to Claim 6 or 7 wherein the apertures are formed as perforations in sheets of suitable material.

9. Apparatus according to Claim 6 or 7 wherein the screens are in the form of a mesh, a material with holes, or wedge wire.

10. Apparatus according to any of Claims 5 to 9 wherein the, or each, screen diverges upwardly away from the float and is planar, convex or concave.

11. Apparatus according to any of Claims 5 to 10 wherein the apertured region extends to the opening.

12. Apparatus according to any of Claims 6 to 10 wherein the screening means may comprise a non-apertured region.

13. Apparatus according to Claim 12 wherein the non-apertured region is provided between the opening and the apertured region.

14. Apparatus according to any of Claims 3 to 13 wherein the cover means is provided with wash means to wash solids retained by the screening means therein back to the storm drain.

15. Apparatus according to Claim 14 wherein the wash means is in the form of showers provided at the top of the cover means.

16. Apparatus according to any of Claims 3 to 15 wherein the float comprises a first section of a size less than the size of the opening thereby to allow material to pass out of the cover around the float when the float is in the open position.

17. Apparatus according to Claim 16 wherein the float means further includes a second section extending downwardly from the first section and having a size greater than the size of said opening such that when the float means is in the open position the second section is below the bottom of the cover means and when the float means is in the closed position the second section engages the bottom of the cover to occlude the opening.

18. Apparatus according to Claim 17 wherein the second section diverges outwardly from the first section, and floatation member is provided on the second section whereby when liquid in the storm drain rises to the level of the float, the floatation member enables the float to float on said liquid.

19. Apparatus according to Claim 18 wherein the floatation member is in the form of a collar of a suitably buoyant material arranged around the second section.

20. Apparatus according to any of Claims 17,18 or 19 wherein the float further includes a third section extending upwardly from the first section, the third section being of such a shape and size as to divert onto the screenng means material passing out of the conduit into the cover.

21. Apparatus according to Claim 20 wherein the third section diverges outwardly from the first section.

22. Apparatus according to any of Claims 17 to 21 further includes restraining means on the second section of the float to engage solids screened by the screening means when the float is in the closed position.

23. Apparatus according to Claim 22 wherein the restraining means is in the form of a plurality of hooks to engage said solids when the float is in the closed position, and to hold said solids when the float moves to the open position.

24. Apparatus according to any preceding claim wherein support means is provided on the cover means to support the float when it is in the open position.

25. Apparatus according to Claim 24 wherein the cover has a top and at least one side and comprises a housing extending around the top and the, or each, side.

26. Apparatus according to Claim 25 wherein the support means comprises a shaft extending downwardly from the top and a substantially flat plate to engage the float means.

27. Storm drain overflow control apparatus substantially as herein described with reference to and as shown in the accompanying drawings.

28. Any novel subject matter or combination including novel subject matter herein disclosed, whether or not within the scope of or relating to the same invention as any of the preceding claims.