AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION INNOVATION PATENT HORIZONTAL FLOW LEAF FILTER The following statement is a full description of this invention, including the best method of performing it known to me: 1 HORIZONTAL FLOW LEAF FILTER BACKGROUND [001] Rainwater tank inlet strainers are prone to leaf build up as unfiltered leaf bearing rainwater flows into the strainer, eventually the leaves cause a blockage of the strainer preventing the majority of the rainwater entering the rainwater tank. In addition leaf build up in the strainer may rot and taint the water in the rainwater tank. Although there are other leaf filters, most leaf filters are vertical and require one leaf filter installation per downpipe. This invention is devised to provide one installation of a leaf filter for multiple downpipes. BACKGROUND ART [002] Innovation Patent No. 200910093, Self Flushing Leaf Filter, is the background art for this Innovation Patent. SUMMARY OF INVENTION Technical Problem [003] During development and prototyping of the Self Flushing Leaf Filter, (Innovation Patent No. 200910093), it was found that flat leaves of various sizes would remain on the flat mesh filter element and would not flush to the outlet end of the filter assembly as well as leaves that were not flat. Solution to Problem [004] For this invention a longitudinally corrugated underside filter assembly was developed. The corrugated underside filter assembly is comprised of a corrugated underside main body and corrugated underside filter element whereby the corrugations run longitudinally along the filter assembly underside. Advantageous Effects of Invention [005] The corrugated underside filter assembly makes a substantial contribution to the working of the Horizontal Flow Leaf Filter in that contact surface area between a flat leaf and the filter assembly main body and filter element is greatly reduced, and consequently friction between a flat leaf the filter assembly main body and filter element is greatly reduced.
2 [006] The corrugated underside filter assembly makes a substantial contribution to the working of the Horizontal Flow Leaf Filter in that water will flow into the corrugation channels and partially lift leaves from resting on the top of the corrugations. [007] The corrugated underside filter assembly of the Horizontal Flow Leaf Filter has been demonstrated to substantially contribute to improved movement of leaf build up in a direction toward the filter assembly outlet compared to the flat underside filter assembly of the Self Flushing Leaf Filter. Description [008] The Horizontal Flow Leaf Filter in accordance with this invention has been devised to provide a substantially improved Horizontal Flow Leaf Filter whereby the underside of the filter assembly is corrugated effecting a substantial contribution to the working of the invention in having the effect of reducing leaf surface area contact, reducing leaf friction and increasing progression of leaf build up. [009] The Horizontal Flow Leaf Filter in accordance with this invention, comprises a corrugated underside filter assembly, an inlet adaptor and an outlet adaptor. The inlet and outlet adaptors are dimensioned to mate with typical stormwater downpipe and facilitate fitment and removal of the corrugated underside filter assembly. The inlet adaptor and outlet adaptor can be either affixed to the rainwater tank strainer or mounted above the rainwater tank strainer by any means with the corrugated underside filter assembly being mounted horizontally between the inlet adaptor and outlet adaptor. [010] The corrugated underside filter assembly comprises of a corrugated underside main body and corrugated underside filter element. The corrugated underside main body is rectangular in cross section, having an inlet end, an outlet end and a cut away section on the underside of the main body which continues partially up the body sides and longitudinally along the underside of main body. The corrugated underside filter element is affixed to the main body from the inside of the main body and completely covers the cutaway section of the main body. The corrugated underside main body is preferably made from PVC plastic, and the corrugated underside filter element is preferably aluminium or stainless steel mesh or micro screen materiel however, other materials can also be used. For example galvanised 3 steel rectangular downpipe could be used as an alternate material for the main body and the corrugated filter element could be perforated sheet metal or plastic. [011] The inlet adaptor and outlet adaptor are dimensioned to fit typical rainwater downpipe to the outward facing ends. The outward facing inlet adaptor and outlet adaptor ends are typically circular in cross section and the inward facing ends of the inlet adaptor and outlet adaptor are rectangular in cross section. The inlet adaptor and outlet adaptor inward facing ends are dimensioned to provide means of retaining the corrugated underside filter assembly and facilitates the removal of the corrugated underside filter assembly by upward horizontal lifting of the corrugated underside filter assembly from the inlet and outlet adaptors and installation of the corrugated underside filter assembly by downward horizontal placement of the corrugated underside filter assembly between the inlet and outlet adaptors. The inlet adaptor and outlet adaptor are preferably made from PVC plastic however, other materials can also be used. For example galvanised steel inlet and outlet adaptors could be used as an alternate to PVC. Brief Description of Drawings [012] This invention may be better understood by explanation of the operation of the invention with reference to the illustrations of the embodiments of the invention which: [013] Figure 1 is an exploded view of the Horizontal Flow Leaf Filter showing corrugated underside filter assembly and inlet and outlet adaptors. [014] Figure 2 is an assembled view of the Horizontal Flow Leaf Filter comprising of the corrugated underside filter assembly fitted to the inlet and outlet adaptors. [015] Leaf bearing rainwater is supplied to the Horizontal Flow Leaf Filter (comprising 1, 2 & 3) from the rainwater system piping flowing in a longitudinal horizontal direction through the inlet adaptor (2) into the corrugated underside filter assembly (1) with rainwater flow direction being toward the outlet adaptor (3). The leaf bearing rainwater flowing into the corrugated underside filter assembly inlet (4) enters the corrugated underside filter assembly (1) where the rainwater falls through the corrugated underside filter element (5) and into the rainwater tank inlet strainer (not shown). Leaves are carried by the rainwater in a horizontal direction toward the 4 corrugated underside filter assembly outlet (6) and are deposited on the corrugated underside filter element (5) as the rainwater falls through the corrugated underside filter element (5). [016] As leaf bearing rainwater continues to flow into the corrugated underside filter assembly (1), the quantity of leaves deposited on the corrugated underside filter element (5) increases and can begin to restrict the flow of the rainwater through the corrugated underside filter assembly corrugated underside filter element (5). If a restriction of rainwater flow through the corrugated underside filter element (5) occurs due to leaf build up on the corrugated underside filter element (5), rainwater flow into the corrugated underside filter assembly (1) builds up and forces the leaves horizontally along the corrugated underside filter element (5) in a direction toward the corrugated underside filter assembly outlet (6). The horizontal movement of the leaf build up along the corrugated underside filter element (5) in the direction toward the filter assembly outlet (6) exposes the corrugated underside filter element (5) and the rainwater falls through the corrugated filter element into the rainwater tank inlet strainer (not shown). Leaf build up which has been progressively moving horizontally along the corrugated underside filter element (5) in a direction toward the corrugated underside filter assembly outlet (6), exits the Horizontal Flow Leaf Filter (comprising 1, 2 & 3) through the outlet adaptor (3). [017] An example of a typical installation of the Horizontal Flow Leaf Filter may consist of the Horizontal Flow Leaf Filter being mounted directly above a rainwater tank inlet strainer with additional pipe and pipe joints connected to the outlet adaptor (3) in a manner that facilitates the piping of leaves away from the Horizontal Flow Leaf Filter.