AU2008201478A1

AU2008201478A1 - Strainer cover for tanks

Info

Publication number: AU2008201478A1
Application number: AU2008201478A
Authority: AU
Inventors: Wayne Christensen
Original assignee: CHRISTENSEN SHEREE ANN
Current assignee: Christensen Sheree Ann
Priority date: 2008-04-01
Filing date: 2008-04-01
Publication date: 2009-10-15

Description

P/00/011 Regulation 3.2 AUSTRALIA Patents Act 1990 ORIGINAL COMPLETE SPECIFICATION STANDARD PATENT Invention Title: STRAINER COVER FOR TANKS The following statement is a full description of this invention, including the best method of performing it known to us: 1 STRAINER COVER FOR TANKS This invention relates to strainer covers for tanks and in particular, rainwater tanks that form part of a rainwater harvesting or collection system. 5 Conventional rainwater tanks normally include an inlet assembly which has a downpipe or inlet pipe in flow communication with a gutter of a building so that rainwater may flow into the tank from the conduit when required. Alternatively, mains water can flow into the tank if appropriate. 10 The inlet assembly will normally comprise a manhole or inlet opening which has a strainer to prevent any detritus such as bird droppings, insects, dirt, vegetable matter or vegetation including leaves from entering the tank interior. The strainer was usually formed from plastics material such as PVC having a round side wall and had a bottom or base wall having a plurality of 15 radially oriented ribs to which was attached a circular sheet of wire mesh. Normally the wire mesh was located between an inner rib assembly and outer rib assembly. Such a strainer is described at www.rainharvestinq.com.au/tank accessories.asp. 20 However, it will be appreciated that other strainers may have different rib assemblies and a pattern of intersecting ribs forming a latticework to which a wire mesh sheet is attached is described at www.bushmantanks.com. 25 In some cases, the conventional strainers as described above were provided with a strainer cover and these are described at www.bushmantanks.com which were a circular cover having a depending side wall usually formed from black plastics material which engaged with the round wall of the strainer by the use of fasteners such as screws. The 30 strainer cover also normally included an aperture for engaging with the rainwater conduit referred to above.

2 However, it has now been found that if a strainer cover was not used the bottom mesh wall of the strainer was quickly coated with detritus of the type described above and this was difficult to clean, especially if this was done on top of the tank. Usually it was necessary to remove the strainer 5 from the tank and thus it was also necessary to remove a number of fasteners, such as screws before facilitating such removal. The strainer after being cleaned by a hose was then re-attached to the top wall of the tank by the fasteners. However, it will be appreciated that this procedure was time consuming and that it had to be done at periodic intervals of time. 10 In relation to the situation when a strainer cover was utilized it was still found that use of the strainer cover did not prevent insects, algae, dead animals such as frogs and bird droppings from gaining access to the interior of the strainer. This was because the downpipe or inlet pipe extended 15 through an aperture in a top wall of the cover and thus, into the strainer interior. This meant that after a period of time the strainer developed an offensive odour or stench and thus, it was necessary to remove the cover from the strainer and also remove the strainer from the top wall of the tank for a thorough cleaning operation before reinstallation. 20 It therefore is an object of the invention to provide a strainer cover for a tank strainer that substantially reduces cleaning of the strainer. It is a further object of the invention to provide an inlet assembly for a tank which includes the strainer cover discussed above. 25 The strainer cover of the invention has a body which has a continuous peripheral flange and a top wall which is formed from mesh material. Preferably the continuous peripheral flange is also formed from mesh 30 material although it is possible that the flange be also formed from non-mesh material such as imperforate or non-apertured material such as plastics sheet or rubber.

3 It is also preferred that the top wall of the strainer cover has a domed or slightly concave shape in side view. 5 The strainer cover of the invention in use is attached to a strainer which may include the conventional strainer discussed above and this may occur preferably by interference fit wherein the continuous peripheral flange may be formed from flexible or resilient material and thus, may be slid over the side wall of the strainer and held thereon by snug engagement by the 10 interference fit or snap fit. The invention in another aspect relates to an inlet assembly for a water tank which includes: (i) a strainer attachable to a manhole or inlet aperture of a tank 15 for straining or filtering water passed into the tank; (ii) a strainer cover attachable to the strainer having a continuous peripheral side flange and a top wall formed from a continuous sheet of mesh; whereby in use water is passed into an interior of the tank from an 20 inlet conduit or downpipe located above the top wall of the cover. The strainer for use in the inlet assembly of the invention may be a conventional strainer as described above having a bottom wall formed from mesh material and a continuous side wall which may have any suitable 25 shape such as round, rectangular, polygonal or triangular. However, it is desirable to note that the side flange of the strainer cover will suitably have a corresponding shape to the side wall of the strainer. Reference may now be made to a preferred embodiment of the 30 invention as shown in the attached drawings wherein: FIG 1 is an exploded perspective view of the inlet assembly of the invention; 4 FIG 2 is an assembled view of the inlet assembly of the invention shown in FIG 1; FIG 3 shows a schematic view of the strainer cover of the invention spaced from and about to be fitted to the strainer; and 5 FIG 4 shows an assembled view of the strainer cover and strainer shown in FIG 3. The inlet assembly 10 shown in FIG 1 includes strainer 11, strainer cover 12 and downpipe 13 located above strainer cover 12. 10 The strainer 11 has a circular round vertical or side wall 14 which is attached to a top surface 15 of water tank 16 by screws 17. The side wall 14 also has a short horizontal section 18 for location of screws 17 and also has an outer downwardly extending lip or flange 19 best shown in FIG 3. The 15 strainer also has a base wall or bottom wall 20 formed of continuous mesh material 21 which may be formed from fly-wire or other wire mesh. There is also provided a support frame 22 having radial ribs 23 to which the mesh material is attached. Each of the radial ribs 23 terminate in central boss 24. 20 The strainer cover 12 has a top wall 25 formed of mesh material 26 which may be the same or different to mesh material 21. Preferably mesh material 26 has a larger aperture size and thus, apertures 27 or mesh material 26 are larger than the relatively fine apertures of mesh material 21. The strainer cover 12 also has a continuous peripheral flange 28 also 25 preferably made of the same mesh material 26. The top wall 25 is preferably domed or concave as shown in FIG 1, therefore having an apex 29. FIG 2 shows the strainer cover 12 fitted to strainer 10 with downpipe or inlet conduit 13 located above cover 12. 30 FIG 3 shows strainer cover 12 about to be fitted to strainer 10 and to this end, strainer cover 12 is preferably formed from flexible wire mesh which 5 has an inturned outer flange or lip 30 adjacent continuous flange 28 and also an inner horizontal section 31. Strainer 10 also has an inturned inner section 32. 5 FIG 4 shows how strainer cover 12 snugly engages with strainer 10 by interference fit wherein outer lip 30 and flange 28 of cover 12 flexibly or resiliently engages with flange 19 as shown. Horizontal section 31 of cover 12 and horizontal section 18 of strainer 10 are also in abutting relationship. 10 From the foregoing it will be appreciated that the strainer cover 12 of the invention is extremely effectively in use in that it will: (a) stop any detritus such as dead insects or animals or leaves obtaining access to the interior of tank 16 or to interior 33 of strainer 10 which detritus is contained in downpipe 13; 15 (b) by having a mesh top wall 25 the strainer cover will also be exposed to sunlight which will prevent build up of bacteria in interior 33 of strainer 10. As a result of (a) and (b) the cleaning or maintenance of strainer 10 20 will therefore be kept to a minimum.

Claims

1. An inlet assembly for a water tank which includes: (i) a strainer attachable to a manhole or inlet aperture of a 5 tank for straining or filtering water passed into the tank; (ii) a strainer cover attachable to the strainer having a continuous peripheral side flange and a top wall formed from a continuous sheet of mesh; whereby in use water is passed into an interior of the tank from an 10 inlet conduit or downpipe located above the top wall of the strainer cover.

2. An inlet assembly as claimed in claim 1 further including a downpipe or inlet pipe located above the strainer cover. 15

3. An inlet assembly as claimed in claim 1 or claim 2 wherein the strainer cover is attachable to the strainer by interference fit.

4. An inlet assembly as claimed in claim 3 wherein said continuous 20 flange of the strainer cover is in abutment with an adjacent side flange of the strainer.

5. An inlet assembly as claimed in any one of claims 1 - 4 wherein the continuous side flange of the strainer cover is also formed from mesh 25 material.

6. An inlet assembly as claimed in any one of claims 1 - 5 wherein the top wall of the strainer cover has a concave or domed shape. 30

7. A strainer cover for a strainer attachable to a manhole or inlet aperture of a tank for straining or filtering water passed into the tank, said strainer cover being attachable to the strainer and having a top 7 wall formed of mesh material and also having a continuous side flange.

8. A strainer cover as claimed in claim 7 wherein the continuous side 5 flange is also formed from mesh material.

9. A strainer cover as claimed in claim 7 or claim 8 wherein the continuous side flange is adapted to engage with the strainer in an interference fit.