AU772826B2

AU772826B2 - Removable stormwater drain filter system

Info

Publication number: AU772826B2
Application number: AU72303/00A
Authority: AU
Inventors: Trevor R Dorman
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-12-13
Filing date: 2000-12-13
Publication date: 2004-05-06
Anticipated expiration: 2020-12-13
Also published as: AU7230300A

Description

P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Invention Title: REMOVABLE STORMWATER DRAIN FILTER

SYSTEM

Applicant: TREVOR R DORMAN The following statement is a full description of this invention, including the best method of performing it known to me: -2- REMOVABLE STORMWATER DRAIN FILTER SYSTEM Field of the Invention The present invention relates to a removable stormwater drain filter system. In particular, the invention relates to a filter system for use within road-side stormwater drains, the filter being readily removable by a mobile mechanical means.

Background of the Invention Attempts have recently' been made to provide in-line filtration systems for stormwater drains (such as road-side stormwater drains) which utilise a variety of baskets and chambers to capture debris and gross pollutants as they enter the stormwater system. Such systems are promoted as being self-flushing or as being able to be cleared of debris by a vacuum device or the like. While such systems ••go will generally function effectively with smaller and regular sized debris, large or :irregularly sized debris will still cause a blockage problem that will generally 99 9. require such in-line filtration systems to be frequently cleared.

However, such in-line filtration systems can typically not be rapidly cleared, and usually require manual intervention to access, clear and replace the internal filtration baskets used. This is a labour intensive process that tends to reduce the effectiveness of the overall system, as it becomes reliant on manpower.

Additionally, some forms of such systems require the use of expensive and cumbersome vacuum equipment to extract debris from the filtration baskets, such 999999 vacuum equipment often not being strong enough to extract all debris.

A further difficulty with some existing stormwater drain filter systems is that they rely on the action of sprung flaps or the like to provide the overflow system.

Reliance on such mechanical systems in a typically aggressive stormwater drain environment, is likely to lead to mechanical failure and rapid blockage, or at the very least additional maintenance requirements.

-3- It is an aim of the present invention to provide a removable stormwater drain filter system that overcomes, or at least partly alleviates, the abovementioned clearing and maintenance problems.

Summary of the Invention The present invention provides a removable stormwater drain filter system for use in a stormwater drain having a stormwater pit, a removable access cover therefor, a stormwater inlet and a stormwater outlet in fluid communication with the stormwater pit, and a fluid path from the inlet through the pit, to the outlet, wherein the removable stormwater drain filter system includes a filter basket adapted to be pivotally securable to the underside of the access cover to be, in use, within the stormwater pit and located in the fluid path such that fluid enters and passes S 15 through the basket.

In use, debris that enters the stormwater drain will be caught in the filter basket as the fluid passes therethrough. By arranging the basket to be pivotally secured to the underside of the access cover, the stormwater drain filter system becomes easily clearable by, for instance, an automated device capable of lifting the filter basket (and thus the access cover) and inverting the filter basket to allow the access cover to fall away from the filter basket, thus allowing the debris to fall from the basket.

It is envisaged that an automated device similar to that presently used by most Australian local councils to empty household rubbish bins (the so-called 'wheelie bins') would suffice. However, it should be appreciated that a device which is capable merely of raising the access cover to reveal the filter basket may suffice, as the basket may then be easily manually cleared (preferably at waist height) by a single operator.

Description of the Invention The filter basket preferably includes a reinforced lifting means, and is preferably pivotally secured to the underside of the removable access cover via the reinforced lifting means. This allows the access cover to be made from concrete, which is the most commonly used material for such access covers, and which is of course (without reinforcement) relatively brittle. The reinforced lifting means may be such as box section steel members (for instance, hollow RHS sections) attached to the filter basket and in turn to the underside of the access cover, and aligned perpendicularly to the stormwater inlet to allow access to the hollow interiors thereof by lifting forks or the like.

The filter basket may be pivotally secured along any of its top edges to the access cover; in the form mentioned above, via the reinforced lifting means. The basket will most likely be a square or rectangular basket and will thus have four sides defining a rear upper edge, a front upper edge, and side upper edges, all determined in relation to the basket in use, and with the stormwater inlet being the e. forward reference point.

.oo* Preferably, the pivotal attachment of the basket to the access cover is along the rear edge substantially parallel to the stormwater inlet, such that the access cover falls away from the basket when the basket is lifted and inverted. The location of the line of pivotal attachment, the weighting of the access cover, and the 'i configuration of the basket itself may all be adapted or altered to provide a 25 predetermined amount of fall of the access cover when the basket is lifted. In this respect, it may be desired to ensure that the access cover swings as far open as possible when the basket is lifted and inverted, to give immediate access to the contents of the basket. Alternatively, it may be desired that the access cover only partially opens until complete inversion is achieved to ensure that the debris contained therein will not fall out until the basket is moved away from over the top of the stormwater pit.

In this form of the present invention, the front upper edge of the filter basket preferably includes an alignment means to align the front edge with the rear edge of the stormwater inlet (at the front edge of the stormwater pit). In this way, the fluid flows over the front edge into, and through, the basket. In this respect, the basket, or at least the front upper edge of the basket, is preferably the full width of the stormwater inlet so that all of the fluid flows into the basket from the inlet.

The alignment means may be an outwardly projecting lip which extends along the full width of the front upper edge of the basket, to rest on (and extend along the full width of) the rear edge of the stormwater inlet when the basket is in use.

The filter basket preferably has tapered rear and side walls, tapering inwardly from the top of the basket down. In this way, the basket may additionally include overflow outlets near the top of each of the rear and side walls. Such overflow outlets may simply be open apertures which will allow for clear flow of fluid therethrough (down past the exterior of the rear and side walls of the basket) to *".the stormwater outlet, in the event of blockage of the basket, or unexpectedly high fluid flow. In a preferred form of the present invention, the overflow outlets are sized so as to maintain the hydraulic performance of the stormwater drain during peak flow periods, such as in heavy rains and indeed floods.

The filter basket is preferably constructed of a rigid material such as a metal mesh, S: but it will be appreciated that the material may be of any type as is considered S:•i suitable, provided that the material is perforated to allow for fluid flow therethrough. In this respect, it is preferred that the basket be capable of catching material of a size down to about 3mm to 5 mm, whilst allowing smaller material to pass.

From the above description it will be apparent that the present invention provides a stormwater drain filter system that is able to be easily removed from the stormwater drain, and which then provides easy access to the filter basket for mechanical or manual removal of debris. The system does not require the use of in-place vacuum systems to be guided into the drain to remove debris, and it does -6not rely on discrete mechanical flaps or devices for its operation. Indeed, the system of the present invention lends itself well to a mechanical cleaning system that requires the use of only one person and a suitably adapted truck. The truck may be driven around the streets, mechanically lift the basket and access cover, empty the collected contents into a bin on the rear of the truck, and subsequently replace the basket and access cover.

It will also be appreciated that, whilst the system of the stormwater drain filter system of the present invention lends itself to use in stormwater drains, there are other possible uses of the system. For instance, the system may find use in the preventative maintenance of domestic dwellings, strata titled and normal building estates, factories, warehouses, shopping centres, and generally all areas where runoff is concentrated and collected into a drainage scheme.

Brief Description of the Drawings The stormwater drain filter system of the present invention will now be described in relation to a preferred embodiment illustrated in the accompanying drawings.

"'"However, it should be appreciated that the following description is not to limit the generality of the above description.

In the drawings: Figure 1 is a schematic side view of a stormwater drain filter system in accordance with a preferred embodiment of the present invention; and .°oo.

i Figure 2 is a schematic perspective view of the filter basket used in the embodiment of Figure 1.

Description of the Drawings Figure 1 illustrates a stormwater drain filter system 10 for use with a stormwater drain 12 which has a removable access cover 14, a stormwater inlet 16, a -7stormwater outlet 18, and a stormwater pit 20. A fluid path is defined from the inlet 16 via the pit 20 through to the outlet 18.

Directly within that fluid path is a filter basket 22 which is pivotally secured to the underside 24 of the access cover 14 at pivotal connection point 26. In this way, the front of the access cover 14 (generally indicated by the reference numeral 28) will drop down below the connection point 26 when the basket 22 is lifted away from the stormwater drain and is inverted. This exposes the contents of the basket 22.

The filter basket 22 may of course be of any desired shape, and may for instance be generally rectangular in section rather than the generally square configuration illustrated.

To assist in lifting the basket 22 (and thus the access cover 14) there is provided a ***reinforced lifting means (better illustrated in Figure 2) in the form of two hollow, ~box section steel members 32. These two members 32 are rigidly secured to the top of the basket 22 in any known manner, and at their rear ends are connected to i the pivoting means 34 such as by a normal hinging mechanism or the like. The pivoting means 34 is also hinged to the access cover 14 such that the access cover 14 and the members 32 separate when the basket 22 is raised and inverted, giving rise to the pivotal motion described above.

The presence of the hollow interiors 36 of the members 32 allows the forks of a 25 lifting mechanism to be inserted therein to lift the basket 22. This ensures that S. contact is not made directly with the access cover 14, which is usually of course made of concrete and is thus inherently weak in relation to torsion forces.

The filter basket 22 includes overflow outlets in its rear and side walls (38 and respectively). Only two of the outlets are illustrated, namely side outlet 42 and rear outlet 44, and both are shown as apertures through which fluid may flow. In this respect, each of the walls of the basket (namely the side walls 40, the rear wall 38 and the front wall 46) are shown being tapered inwardly from the tops -8thereof to the floor 48 of the basket 22. This assists in allowing unobstructed fluid flow through the overflow outlets 42 and 44, and also assists in allowing easy removal and easy re-alignment for replacement.

Figure 1 also illustrates the alignment means 50 arranged at the front edge of the basket 22 in the form of an outwardly projecting lip extending along the full width of the front of the basket 22. As can be seen, this lip rests on the rear edge of the inlet 16 to assist in ensuring that substantially all of the fluid entering the inlet 16, enters the basket 22.

Finally, it will be appreciated that there may be other variations and modifications made to the configurationis described herein which might also be within the scope of the present invention.

S.0.

S e* e

Claims

1. A removable stormwater drain filter system for use in a stormwater drain having a stormwater pit, a removable access cover therefor, a stormwater inlet and a stormwater outlet in fluid communication with the stormwater pit, and a fluid path from the inlet through the pit, to the outlet, wherein the removable stormwater drain filter system includes a filter basket adapted to be pivotally securable to the underside of the access cover to be, in use, within the stormwater pit and located in the fluid path such that fluid enters and passes through the basket.

2. A removable stormwater drain filter system according to claim 1 wherein the filter basket is pivotally secured to the underside of the access cover via a reinforced lifting means.

3. A removable stormwater drain filter system according to claim 2 wherein the reinforced lifting means is secured to the filter basket and in turn to the underside **fr* of the access cover, and is aligned perpendicularly to the stormwater inlet to allow •access thereto by lifting forks or the like.

4. A removable stormwater drain filter system according to any one of claims 1 to 3 wherein the filter basket is a square or rectangular basket having four sides, being a rear upper edge, a front upper edge, and two side upper edges.

5. A removable stormwater drain filter system according to claim 4 wherein the 25 pivotal attachment of the filter basket to the access cover is along the rear edge S. substantially parallel to the stormwater inlet, such that the access cover falls away from the basket when the basket is lifted and inverted.

6. A removable stormwater drain filter system according to claim 5, wherein the front upper edge of the filter basket includes an alignment means to align the front edge with the rear edge of the stormwater inlet, at the front edge of the stormwater pit.

7. A removable stormwater drain filter system according to claim 6, wherein the alignment means is an outwardly projecting lip which extends along the full width of the front upper edge of the basket, to rest on (and extend along the full width of) the rear edge of the stormwater inlet when the basket is in use.

8. A removable stormwater drain filter system according to any one of claims 1 to 7, wherein the filter basket has tapered rear and side walls, tapering inwardly from the top of the filter basket down.

9. A removable stormwater drain filter system according to claim 8, wherein the filter basket additionally includes overflow outlets near the top of each of the rear and side walls in the form of apertures which allow for clear flow of fluid therethrough to the stormwater outlet, in the event of blockage of the basket, or unexpectedly high fluid flow.

10. A removable stormwater drain filter system according to claim 1 substantially as herein described in relation to the accompanying drawings. DATED: 13 December 2000 PHILLIPS ORMONDE FITZPATRICK Attorneys for: TREVOR R DORMAN S i y