Patent Publication Number: US-2005120506-A1

Title: Counter-rotational electric scrubber

Description:
BACKGROUND OF THE INVENTION  
      The present invention relates to electric motor-driven scrubbers. More particularly, although not exclusively, the invention relates to motor-driven scrubbers having a pair of scrubbing blocks that are driven to counter-rotate about a common axis. Such scrubbing blocks might support a plurality of tufts, polishing pads, scouring pads, sandpaper, cleaning sponges or other surfaces for cleaning, scrubbing, polishing or the like.  
      It is known to provide handheld motor-driven rotary brushing devices provided with a single flat tuft block from which parallel bristles extend. The tuft block in such devices rotates in one direction only. If such a device is left switched on when placed upon a bench for example, it can spin haplessly and run away across the bench. Also, the cleaning action provided by such known devices is limited by the unidirectional rotation of the bristles or other cleaning surface-interactive element.  
     OBJECT OF THE INVENTION  
      It is the object of the present invention to provide a counter-rotating scrubber aimed at overcoming or substantially ameliorating at least one of the above disadvantages.  
     DISCLOSURE OF THE INVENTION  
      There is disclosed herein an electric scrubber, comprising: 
          a housing,     an electric motor mounted within a housing,     a pair of scrubbing blocks mounted to the housing for rotation about a common axis, and     a torque transmission transmitting torque from the electric motor to the scrubbing blocks in such manner that the scrubbing blocks rotate simultaneously in mutually opposite directions about the common axis.        

      Preferably one of the scrubbing blocks has a circular array of inwardly directed teeth and the other of the scrubbing blocks has a circular array of outwardly facing teeth and wherein the torque transmission comprises a pinion meshing with both of said circular arrays of teeth.  
      Preferably the torque transmission further include is a worm gear in mesh with an intermediate gear with which the pinion shares a common shaft.  
      Preferably both circular arrays of teeth are mounted in a common plane.  
      Preferably each scrubbing block comprises surface-interactive elements mounted upon a common plane.  
      Alternatively each scrubbing block comprises surface-interactive elements radiating from a common axis.  
      The electric scrubber might further comprise a dispenser within the housing for delivering a liquid agent to at least one of the scrubbing blocks.  
      In embodiments wherein the scrubber might be adapted for cleaning a toilet, or other hard to reach area, there might further be provided a handle detachable from the housing and encasing a rechargeable battery in circuit with the electric motor via terminals exposed upon detachment of the handle from the housing.  
      The handle might comprise an elongate extension on which the terminals are located and wherein the housing comprises an elongate recess into which the extension is received.  
      There is further disclosed herein a combination comprising the electric scrubber disclosed above and a recharging stand attachable to a source of mains power and comprising an elongate recess into which the extension is received.  
      Definition  
      As used herein, the word “scrubber” and its derivations such as “scrubbing” are intended to encompass any surface-interactive element that performs a scrubbing, brushing, polishing, sanding or cleaning function and the action performed thereby respectively. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      Preferred forms of the present invention will now be described by way of example with reference to the accompanying drawings, wherein:  
       FIG. 1  is a schematic parts-exploded perspective illustration of a counter-rotational electric scrubber,  
       FIG. 2  is a schematic perspective cut-away illustration of the electric scrubber of  FIG. 1 ,  
       FIG. 3  is a schematic parts-exploded perspective illustration of the scrubbing blocks and torque transmission of the electric scrubber of  FIG. 1 ,  
       FIG. 4  is a schematic cross-sectional elevation of counter-rotational electric toilet scrubber,  
       FIG. 5  is a schematic cross-sectional elevation of the scrubbing blocks, electric motor and torque transmission of the toilet scrubber of  FIG. 4 ,  
       FIG. 6  is a schematic cross-sectional end elevation of the components of  FIG. 5  taken at VI-VI,  
       FIG. 7  is a schematic cross-sectional end elevation of the components of  FIG. 5  taken at VII-VII,  
       FIG. 8  is a schematic parts-exploded perspective illustration of an alternative torque transmission for an electric scrubber,  
       FIG. 9  is a schematic parts-exploded perspective illustration of a further alternative torque transmission for an electric scrubber,  
       FIG. 10  is a schematic parts-exploded perspective illustration of still a further alternative torque transmission for an electric scrubber,  
       FIG. 11  is a schematic parts-exploded perspective illustration of yet a further alternative torque transmission for an electric scrubber,  
       FIG. 12  is a schematic parts-exploded perspective illustration of yet still a further alternative torque transmission for an electric scrubber,  
       FIG. 13  is a schematic cross-sectional elevation of an electric toilet scrubber, similar to that of  FIG. 4 , but having a detachable handle in which rechargeable batteries are housed,  
       FIG. 14  is a schematic cross-sectional elevation of the be electric toilet scrubber of  FIG. 13  showing the handle detached,  
       FIG. 15  is a schematic elevation of the detached handle of  FIG. 14  mounted upon a recharging stand, and  
       FIG. 16  is a schematic elevation of the detached handle and recharging stand of  FIG. 15 , with the handle lifted from the stand. 
    
    
     DESCRIPTION OF THE TO A A THE THE PREFERRED EMBODIMENTS  
      In  FIG. 1  of the accompanying drawings there is depicted schematically an electric body scrubber for use in the shower or bath comprising a housing provided by a cover  7  and a base  3 . The cover  7  houses a plate  8  on which there is mounted an electric switch  6  activatable upon depression of a sealed pushing pad  71  on the cover.  
      There is an electric motor  501  attached to a frame  9  that is in turn secured to a base  3 . A rechargeable battery pack  4  is fitted upon the base  3  and provides power to the electric motor  501  when the switch  6  is depressed. The housing is sealed against the ingress of water from the outside.  
      A worm gear  503  is secured to the output shaft of the electric motor  501 . The frame  9  supports the worm gear  503  as well as an intermediate gear  502  with which the worm gear  503  meshes The depending shaft from the intermediate gear  502  passes through the base  3 . At the bottom side of the base, a pinion  504  is secured to the intermediate gear shaft so as to rotating in unison with the intermediate gear  502  at all times that the motor  501  is activated.  
      There is a pair of scrubbing blocks  1  and  2  mounted rotatably about a common axis A to the base  3 . The scrubbing block  1  surrounds the scrubbing block  2  and comprises a circular array of inwardly facing teeth  11 . The scrubbing block  2  has a circular array of outwardly facing teeth  22 . The pinion  504  meshes with both of the teeth arrays  11  and  22  to effect counter-rotation of the scrubbing blocks  1  and  2 .  
      There is a detergent reservoir  20  fitted within the housing between the cover  7  and base  3 . It has a lid  10  accessible via an opening  72  in the cover  7  which can be removed to poor liquid detergent into the reservoir. A flexible hose  13  extends from a coupling  12  at the bottom of the reservoir  20  through the base  3  to the scrubbing block  2 .  
      An alternative embodiment of the invention is depicted in  FIGS. 4 and 5 . This embodiment is a toilet scrubbing brush  400  having a handle  409  and counter-rotating scrubbing blocks  402  and  403  mounted to rotate in opposite directions about an axis A. A pair of batteries  411  is housed within the handle  409  and electrical contacts  410  and  412  convey current via a switch  413  and conductor  414  to an electric motor  405 . The batteries might be rechargeable or dry cell batteries. The scrubbing blocks  402  and  403  are driven to counter-rotate in the same nanner as described with reference to the embodiment of FIGS.  1  to  3 . To this end, the electric motor  405  drives a worm gear  417  that in turn drives an intermediate gear  418  upon a common shaft with pinion  419  in mesh with inwardly and outwardly directed circular arrays of teeth.  
      Alternative motor-to-scrubbing block torque transmission arrangements are shown in  FIGS. 8, 9 ,  10  and  11 . In  FIG. 8 , the electric motor  501  is still mounted transversely, but its output pinion  503  meshes with a crown wheel  502 . A pinion  504  is connected to the crown heel  502  and drives the scrubbing blocks  1  and  2 .  
      In the embodiment depicted in the  FIG. 9 , instead of providing a circular array of teeth and a pinion, output torque of the intermediate gear  502  is transferred by a wheel  504  that might be formed of rubber or other high-grip material that rolls upon high-grip surfaces  101  and  201  respectively. This arrangement would provide some degree of slippage in the transmission.  
       FIG. 10  shows an arrangement wherein the motor  501  is mounted longitudinally, having a reduction gearbox  502 . The pinion  503  is mounted directly upon the output shaft of the reduction gearbox  502 .  
       FIG. 11  shows a similar arrangement to that of  FIG. 10 , however the output shaft of the reduction gearbox  502  directly drives the inner-most scrubbing block  2 . In this case, the pinion  503  would be mounted upon a shaft that is fixed with respect to the housing to transfer rotation to the scrubbing block  1 .  
      In  FIG. 12 , there is depicted a belt-drive arrangement in which the electric motor  501  has an output pulley  503  about which a belt extends. The belt passes around a pulley  502  to which the pinion  504  is attached.  
      In  FIGS. 13 and 14 , a toilet scrubbing brush having a detachable handle  9  is shown. Rechargeable batteries  11  are housed within the handle  9 . The handle includes a longitudinal protrusion  130  that is received in interlocking manner within a longitudinal recess  131  of the main body  6 . There might be electric terminals upon the protrusion  130  and correspondingly within the recess  131  by which power is conveyed from the batteries to the electric motor.  
      The batteries  11  can be recharged by placing the handle  9  upon a recharging stand  140  as shown in  FIG. 16 . The recharging stand  140  is attached electrically to a transformer plug pack  23  and includes a recess  21  into which the protrusion  130  of the handle  9  is received. There is a plug  141  received within a socket  142  as shown. The batteries  11  might received electric current via direct terminal-contact or via a pair of interacting coils (not shown)—one within the protrusion  130  and another about the recess  21 .  
      It should be appreciated that modifications and alterations obvious to those skilled in the art are not to be considered as beyond the scope of the present invention. For example, where bristles such as  401  are depicted in the drawings, polishing pads, scouring pads, sponge pads, sandpaper or other scrubbers can be used depending on the required application of the scrubber.