Abstract:
A filter assembly ( 10 ) for guttering down pipe ( 12 ) comprising a hollow body ( 13 ) having an internal base ( 24 ) and a conical filter ( 14 ) located within the body above the base and through which all the water must pass. The body ( 12 ) having a pair of opposed couplings ( 18, 21 ) for connection into a down pipe ( 12 ) and the filter ( 14 ) is arranged with its apex directed upwardly in use.

Description:
FIELD  
         [0001]    This invention relates to filters particularly for use in the down pipes or drain pipes for rain water gutters.  
         BACKGROUND OF THE INVENTION  
         [0002]    Rain water gutters as used just below the eaves of roofing frequently fill with leaves, silt, moss and other debris which is collected on a roof and then washed into the guttering by the rain water. The silt and leaves may then be washed into the down pipe where the lower portions of the pipe may become blocked. This is a particularly bad problem where the down pipe extends directly into an under soil soak-away and any blockage may only be detected when the pipe is full and water flows out through higher joints in the pipe, which may cause problems with damp and brickwork.  
           [0003]    A known partial solution to the problem is to cover the upper mouth the down pipe, where it links with the gutter, with mesh so as to prevent leaves from entering the down pipe. This does not prevent silt from entering the down pipe to prevent accumulations of silt from building up within the pipe, and requires that maintenance to remove trapped leaves is effected at the guttering which is not always convenient, and may not always take place when the pipe is blocked, since it is not generally easily observable.  
           [0004]    The present invention provides a filter assembly which can be fitted to the down pipe at a convenient level to facilitate maintenance at ground level.  
         STATEMENTS OF THE INVENTION  
         [0005]    According to the present invention there is provided a guttering down pipe filter comprising a hollow body having a pair of opposed couplings for connection into a down pipe and an internal base on which a water filter located within the body above the base and through which all the water must pass, the filter being substantially conical in shape with the apex directed upwardly in use.  
           [0006]    Having the filter located above the base ensures that most silt is collected on the base before the water passes through the filter located above the base.  
           [0007]    The filter may comprise wire mesh deformed to the required shape, a coarse open cell foam, porous sheet metal formed into a cone, or a hollow moulded plastic cone having a plurality of through holes or apertures formed in its surface.  
           [0008]    The filter sits on the base of the body and preferably has a non porous portion adjacent said base. This allows silt or other debris to collect on the base in the space between the non porous portion and the body wall.  
           [0009]    The body is preferably a cylindrical body comprising upper and lower telescopically interengaging body portions, each having one of said couplings formed at its free end with the filter being formed integrally with the lower body portion, preferably the filter and body portion are formed as a single plastics moulding.  
           [0010]    Said couplings in use comprise upper and lower cylindrical couplings which telescopically engage with oppositely extending portions of the down pipe, the lower coupling engaging within the down pipe and including an outer concentric cylindrical skirt which surrounds the adjacent portion of down pipe. This helps mask the otherwise exposed end of the pipe. The upper coupling slides over the external surface of the respective portion of down pipe. The upper coupling may include a radial screw which in use secures the filter assembly to the respective portion of down pipe.  
           [0011]    At least a portion of said body, preferably the lower body portion, is formed from a transparent material allowing the filter to viewed from outside the assembly. The lower body portion may be moulded from a suitable transparent plastics material such as PET ( polyethyleneteraphthallate), polycarbonate, PVC, etc.  
       
    
    
     DESCRIPTION OF THE DRAWINGS  
       [0012]    The invention will be described by way of example and with reference to the accompanying drawings in which:  
         [0013]    [0013]FIG. 1 is a schematic sectional view of a filter assembly according to the present invention,  
         [0014]    [0014]FIG. 2 is sectional view of a filter used in the assembly of FIG. 1.  
         [0015]    [0015]FIG. 3 is side elevation of an alternative filter,  
         [0016]    [0016]FIG. 4 is a bottom view of the filter of FIG. 3, and  
         [0017]    [0017]FIG. 5 is a section on the line V-V in FIG. 3 showing the overlapping frustoconical portions of the filter. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0018]    With reference to FIG. 1, there is shown in schematic form a filter assembly  11  for use with guttering down pipe  12  as is used with rain water guttering commonly fitted under the eaves of rooves.  
         [0019]    The filter assembly  11  comprises a hollow cylindrical body  13  housing a filter  14 . The filter  14  is conical in form and is secured within the body  13  with its apex pointing upwards in use. The filter  14  is a coarse filter suitable for stopping leaves and may be shaped by deforming wire mesh. Alternatively, as shown in FIG. 2, the filter  34  may be a hollow cone  35  having spaced holes  36  (about 3 mm-6 mm in diameter) passing through its shell.  
         [0020]    The body  13  comprises two telescopic parts  16  &amp;  17 , the upper cylindrical part  16  being sealingly slidable within the lower cylindrical part  17 .  
         [0021]    The upper part  16  has a coupling  18  formed at its upper end which in use sealingly slides over the outer surface of a respective portion of down pipe  12 . The upper part  16  may be held in place on the down pipe by a radial screw  19 .  
         [0022]    The lower part  17  has a coupling  21  formed at its lower end which has an inner portion  23  which in use slides within a portion of respective down pipe  12 . The coupling  21  also includes an outer concentric skirt  22  radially spaced from the inner portion  23  and which in use masks an end portion of down pipe  12 . An annular seal  25  ( see FIG.2) may be located within the radial space between the skirt  22  and inner portion  23 .  
         [0023]    The filter  14  sits on the base  24  of the lower body portion  17 , and any leaves and/or debris collect in the space  26  formed between the filter  14  and the cylindrical sidewalls of the body  13 . The porous portion of the filter  14  is preferably raised above the base  24  as is best seen in FIG. 2  in which the holes  36  of the hollow conical filter  34  are spaced from the base  24  by an impervious rim  37 . This allows silt to collect in the space  38  between the rim  37  and the inner side wall of the lower body portion  17 .  
         [0024]    The filter  34 , base  24 , and lower body portion  17  may be formed as a single moulding, or may be assembled from a plurality of individual parts. The lower body portion  17  is preferably moulded from a transparent thermoplastic material allowing the state of the filter to be observed from outside of the filter assembly without removal of the assembly from the down pipe. This should prevent un-necessary maintenance and warn of impending blockages.  
         [0025]    Yet another filter  44  is shown in FIGS.  3 - 5 . The filter  44  is a thermoplastics moulding comprising a plurality of frustoconical portions of progressively different sizes, sitting one upon another, preferably four portions  45 , 46 , 47 , 48 . The portions  45 - 48  are substantially impervious to water and each overlap with the respective adjacent portions so that there is an annular gap  50  between pairs of overlapping portions. Overlapping adjacent portions  48 , 47 :  47 , 46 :  46 , 45  are connected through a plurality of equiangularly spaced thin bridges  51 . The bridges in this case are aligned with each other but could be arranged in other ways. The bridges  51  divide the annular gaps  50  into arcuate apertures through which the water will flow. The bottom frustoconical portion  48  spaces the first gap  50  from the base  24  to ensure that debris collects in the space  38  as previously described. The overlap of each gap  50  by the adjacent higher frustoconical portion prevents debris from flowing through the apertures and directs debris to the base  24 .  
         [0026]    If a blockage occurs, or during preventive maintenance, the filter assembly is simply removed from the down pipe and dis-assembled for cleaning.