Patent Publication Number: US-6336239-B1

Title: Bin washer

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of International Application No. PCT/AU98/00516, filed Jul. 3, 1998. 
    
    
     FILED OF THE INVENTION 
     This invention relates to an apparatus for washing bins and particularly to a bin washer that washes domestic bins of the wheelie bin type. 
     BACKGROUND OF THE INVENTION 
     There has always been a problem with effectively washing rubbish bins in general. This is due to their size and elongate shape which hampers free and full access to the interior of the bin during cleaning. Another problem is draining of the cleaning fluid. Often this will involve turning the bin onto its side or inverting the bin. This increases the time required to effectively clean a bin and consequently where it is necessary to clean a large number of bins, the process becomes increasingly more difficult. 
     One method of cleaning bins involves using a truck mounted system which picks up the bin and holds it in an inverted or inclined position. An operator then uses a hand held spray gun to spray cleaning fluid under pressure into the bin. The cleaning fluid self drains from the bin onto a screen so as to remove any unwanted solids. The cleaning liquid is stored in a holding container and is then recycled via a pump back to the spray gun. This method is a vast improvement over the manual methods of cleaning. However it is considered that this method is still not overly quick and may have difficulty in removing grime caked on the bin. 
     It is therefore an object of this invention to provide an alternate apparatus for cleaning bins with increased efficiency. 
     SUMMARY OF THE INVENTION 
     According to the present invention there is provided a mobile cleaning system for a bin including: 
     a self propelled vehicle; 
     a bin manipulation arm for gripping, lifting and inverting a bin; 
     an apparatus for cleaning a bin supported on said vehicle, the apparatus comprising a single elongate rotatable stem locatable at a fixed spatial position within a bin when the bin is held in an inverted state by said bin manipulation arm, said stem adapted to transfer cleaning liquid to the inside of the bin and arranged to support a brush means contacting the inside of the bottom and side walls of said bin in a manner so that in one complete revolution of the stern substantially the whole of the inside of the bottom and side are contacted by the brush means; 
     stationary spray means for spraying cleaning fluid onto an inside surface of a lid of said bin when the bin is in the inverted state; 
     a catchment tank supported an said vehicle in which said stem and stationary spray means arc located for collecting said cleaning liquid; and, 
     whereby, in use, the bin manipulation arm grips. lifts and inverts the bin and holds said bin over said stem and the catchmont tank and said stem is rotated and cleaning fluid supplied to said stem so that refuse is removed from the inside of the bin by a combination of the cleaning fluid and rotating brush means, and wherein said cleaning fluid and debris washed from said bin fall into said catchment tank. 
     Preferably said vehicle includes a hydraulic motor at a lower end of said stem for applying torque to rotate the stem, wherein said hydraulic motor is driven by said cleaning fluid. 
     Preferably said cleaning fluid is water delivered to said stem at a pressure in the range of 70-200 kpa and a temperature between 80-110° C. 
     According to another aspect of the present invention there is provided a mobile cleaning system for a bin including: 
     a vehicle; 
     an apparatus for cleaning a bin in accordance with the first aspect of the present invention; 
     bin manipulation arm for gripping, lifting and inverting a bin; and, 
     catchment tank through which the stem of the apparatus extends, 
     whereby, in use, the bin manipulating arm grips, lifts and inverts the bin and holds the bin over both the stem and the catchment tank so that cleaning fluid and debris washed from the bin fall into the catchment tank. 
     Preferably the catchment tank includes filter means for filtering the cleaning fluid transferred by the stem and debris from the bin, and means downstream of the filter means to allow filtrate to be recycled as cleaning fluid for washing a subsequent bin. 
     The objects set forth above as well as further and other objects and advantages of the present invention are achieved by the embodiments of the invention described hereinbelow. 
     For a better understanding of the present invention, together with other and further objects thereof, reference is made to the accompanying drawings and detailed description and its scope will be pointed out in the appended claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings in which: 
     FIG. 1 is a section view of an apparatus for a bin; 
     FIG. 2 is a plan view of a mobile cleaning system for a bin incorporating the apparatus shown in FIG. 1; and 
     FIG. 3 is a side elevation of the cleaning system shown in FIG.  2 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to FIG. 1, it ran be seen that an apparatus  10  for cleaning a bin  12  includes an elongate rotatable stem  14  that is locatable within the bin  12 , the stem  14  adapted to transfer cleaning liquid to the inside of the bin  12  and arranged to support brush means  16  for contacting the inside of the bin  12  whereby, in use, refuse can be removed from the inside of the bin  12  by the combination of the cleaning fluid and the rotating brush means  16 . 
     The stem  14  includes at one end a laterally extending arm  18 . The brush means  16  includes two brushes  16 A that are attached to the arm  18  and positioned so that when the bin  12  is supported in an inverted stated over the stern  14  the brushes  16 A contact the inside of a bottom wall  20  of the bin  12 . 
     The brush means  16  also includes a series of further brushes  16 B attached along a length of the stem  14  substantially equal to the depth of the bin  12  starting from a point adjacent the arm  18 . In this way, when the stem  14  rotates the brushes  16 A and  16 B are able to contact the entire inside surface of the bin  12  to the exclusion of the bin&#39;s lid  22 . Cleaning of the inside surface of the lid  22  is achieved by the use of stationary spray means in the form of a spray bar  24  which is in fluid communication with a supply of the cleaning fluid transferred by stem  14 . The spray bar  24  includes a plurality of nozzles  26  which direct a spray of the cleaning fluid onto the inside surface of the lid  22 . 
     A number of further nozzles  28  are provided along the length of the stem  14  and the. arm  18  to spray cleaning fluid onto the inside surface of the bin  12 . 
     Motive force to rotate the stem  14  about its length is provided by a hydraulic motor  30  located at an end of the stem  14  opposite the arm  18 . Advantageously, though not essentially, the hydraulic motor  30  is driven by the cleaning fluid used for cleaning the inside of the bin  12 . A rotary seal  32  is provided about the circumference of the stem  14  at the end adjacent the motor  30  to prevent loss of cleaning fluid. The cleaning fluid is supplied via a supply conduit  34  which feeds into the motor  30 , stem  14  and the spray bar  24 . 
     As is apparent from FIG. 1, when the bin  12  is supported in an inverted condition with the stem  14  located inside the bin  12 , and cleaning fluid is supplied via conduit  34  the cleaning fluid drives the motor  30  to cause the stem  14  to rotate. As the stem  14  rotates the cleaning fluid is also sprayed or ejected from the nozzles  28  and the brushes  16 A and  16 B scrub the inside surface of the bin  12 . Cleaning fluid is also sprayed via nozzles  26  onto the inside surface of the lid  22 . The ejected or sprayed cleaning fluid together with debris scrubbed from the bin  12  falls from the bin  12  by action of gravity. 
     In order to enhance the cleaning action it is preferred that the cleaning fluid be at an elevated pressure and temperature. More particularly, the cleaning fluid may be supplied at a pressure in the order of 150 kpa gauge pressure. This results in the cleaning fluid being sprayed with considerable force onto the inside surface of the bin  12  so that the pressure of the liquid itself can dislodge debris on the inside of the bin. Further, by having the fluid temperature elevated say at between 80° to 110° celcius harmful bacteria may be killed without the use of chemical disinfectants and germicides. Ideally the cleaning fluid is water and it is provided at the elevated temperature and pressure by use of the WAIPUNA™ system. This system provides a supply of water at elevated temperature and pressure. 
     The apparatus  10  can be incorporated into a mobile cleaning system  36  for bins shown in FIGS. 2 and 3. The system  36  includes: a vehicle in the form of a tray top truck  38 ; the apparatus  10  mounted on the truck  38 ; a bin manipulating arm or bin lifter  40  for gripping, lifting and inverting a bin  12 ; and, a catchment tank  42  mounted an the truck  38  and through which the stem  14  passes. When used, the bin lifter  40  grips, lifts and inverts the bin  12  and holds the bin  12  over both the stem  14  and the catchment tank  42  so that the cleaning fluid used in cleaning the bin and the debris washed from the bin fall into the catchment tank  42 . 
     The bin lifter  40  is designed so that it holds the bin in an inverted position while cleaning takes place with the inside of the bottom wall  20  in contact with the brushes  16 A and brushes  16 B in contact with the inside of the side walls of the bin. A filter means in the form of a mesh screen  44  (shown mostly clearly in FIG. 1) extends diagonally across the catchment tank  42  to filter the cleaning fluid and debris failing from the bin  12 . Typically the screen  44  will have a mesh spacing of less than one millimetre so that any solid of a greater size than that cannot pass therethrough. Basically, the screen  44  acts to separate the cleaning fluid from the solids. The cleaning fluid and any solid particle of a size less than that of a mesh size passes through the mesh  44  and can be drawn off through outlet  46  at the bottom of tank  42  to be recycled and reused in the cleaning process. To this end, the system  36  includes a pump  48  mounted on the truck  38  and having a suction line  50  connected with the outlet  46 . A discharge line  52  of the pump leads to a water storage tank  54  that holds a supply of water for use in cleaning of the bins  12 . Solid wastes which do not pass through the screen  44  collect in the tank  42  and can be removed via an outlet  56  in a tank  64 . A second pump  58  mounted on the truck  38  has a suction line  60  coupled to the outlet  56  and a discharge line  62  leading to a solid waste storage tank  64  also mounted on the truck  38 . 
     Both the tanks  54  and  64  are provided with inclined screen like bottom surfaces which act as filters to separate solid matter from the cleaning liquid. The screen like surfaces are shown as item  66  in the tank  54  and item  68  in tank  64 . Thus, any water settling out of the solid waste stored in tank  64  passes through the screen  68  and can be returned to the water storage tank  54 . Water for cleaning is drawn from tank  54  from a point below screen  66 . 
     A valve  70  is provided in the side of tank  54  to allow filling and emptying of the tank  54 . Similarly a valve  72  is provided on the side of tank  64  to allow extraction of the solid waste from that tank. 
     A WAIPLTNA™ system  74  is also mounted on the truck  38  to heat and pressurise the water from tank  54  to a pressure in the range of 70-200 kpa gauge pressure and a temperature of between 80-110° Celcius. Although it is believed that an ideal temperature and pressure combination of the water would be 100° Celcius at 250 psi. Water from the storage tank  54  passes via pipe  75  to the WAIFTNA™ system  74  and is then supplied via pipe  77  to the stem  14  for transfer to the inside of the bin  12 . 
     It is envisaged that the mobile cleaning system  36  would be used in tandem with conventional garbage collection trucks so that after the bin has been emptied of refused the garbage truck the system  36  will follow to clean the bin. 
     Now that embodiments of the present invention have been described in detail, it will be apparent those skilled in the relevant arts and numerous modifications and variations may be made without departing from the basic inventive concepts. For example, the nozzles  28  can be removed and the stem  14  is to be provided with a series of holes so as to act like a manifold spraying cleaning fluid into the bin  12 . Also, the brushes  16 A and  16 B can be demountably retained on the stem  14  or arm  18  to allow easy replacement or repair. Also other configurations of brushes can be used for example a spiral brush wound around the stem  14 . If desired cleaning agents or deodorants may be added to the water used as the cleaning fluid although it is preferred that it be non foaming so as to not effect the operation of any pumps used to pumping the cleaning liquid. Also, the motor  30  can be driven by a hydraulic fluid rather than the cleaning fluid. Alternately, the stem  14  can be rotated by use of belts and pulleys or in any other conventional method. 
     All such modifications and variations are deemed to be within the scope of the present invention the nature of which is to be determined by the aforegoing description and the appended claims. 
     Although the invention has been described with respect to various embodiments, it should be realized this invention is also capable of a wide variety of further and other embodiments within the spirit and scope of the appended claims.