Abstract:
An extractor comprises a foot assembly supported by at least one wheel at a rearward portion thereof and at least one rotatable agitator at a forward portion thereof, a fluid delivery system, a fluid recovery system and an extension with a first end aligned with an inlet for an extraction path and a second end in register with a surface to be cleaned. The foot assembly can be traversed over the surface to be cleaned in alternating forward and rearward movements. Movement of the foot assembly in a rearward direction supports the forward portion of the foot assembly on the extension in a first position and the at least one agitator and movement of the foot assembly in a forward direction shifts support of the forward portion of the foot assembly off of the extension in a second position.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application No. 61/264,546, filed Nov. 25, 2009, which is incorporated herein by reference in its entirety. 
     
    
     BACKGROUND 
       [0002]    A wet extractor is a common device for cleaning a surface by delivering a cleaning fluid to a surface to be cleaned and removing the cleaning fluid and any debris from the surface. Some examples of wet extractors are disclosed in commonly assigned U.S. Pat. No. 6,131,237 to Kasper et al. and U.S. Patent Publication No. 2007/0226943 to Lenkiewicz et al. 
         [0003]    U.S. Pat. No. 3,815,171 to Carr et al. discloses a suction nozzle configured for attachment to a vacuum hose for cleaning a carpet or rug. The nozzle comprises an inlet fluidly connected to a suction chamber portion. A brush unit comprising bristles projects below the inlet. The nozzle further comprises a pivotable rake that comprises a plurality of hollow tines fluidly connected to the suction chamber such that when the nozzle is pulled rearwardly, the rake automatically pivots about a hinge rod into an operative position where suction is drawn through the hollow tines and when the nozzle is pushed forwardly, the rake automatically pivots into a non-operative position. 
         [0004]    U.S. Pat. No. 4,100,644 to Johansson discloses a vacuum cleaner nozzle comprising a rake-like part for cleaning a surface. The rake-like part comprises a plurality of tubular teeth forming air passages sharing a common air channel. When the nozzle is moved rearwardly, the teeth engage with a surface to be cleaned and are rotated into a lowered position such that the air channel is fluidly coupled with the suction channel via a hole. Movement of the nozzle in a forward direction retracts the teeth into the nozzle whereby a suction opening is fluidly coupled with the suction channel via a second air channel. 
         [0005]    U.S. Patent Publication No. 2008/0016642 to Thomas discloses a spray extraction nozzle including a suction duct with a suction inlet configured to contact a surface to be cleaned. An adapter is pivotally mounted near the suction inlet and configured to pivot between an operating position where the adapter contacts the surface and a rest position where the adapter is pivoted away from the suction inlet and out of contact with the surface. The nozzle further comprises a releasable locking means for selectively locking the adapter in the operating position. 
       BRIEF SUMMARY 
       [0006]    According to one embodiment, the invention comprises an extractor comprising a foot assembly supported by at least one wheel at a rearward portion thereof and at least one agitator at a forward portion thereof, a fluid delivery system, a fluid recovery system and an extension with a first end aligned with an inlet for an extraction path and a second end in register with a surface to be cleaned. The foot assembly can be traversed over the surface to be cleaned in alternating forward and rearward movements. Movement of the foot assembly in a rearward direction supports the forward portion of the foot assembly on the extension in a first position and the at least one agitator and movement of the foot assembly in a forward direction shifts support of the forward portion of the foot assembly off of the extension in a second position. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    In the drawings: 
           [0008]      FIG. 1  is a front perspective view of an extractor according to one embodiment of the invention. 
           [0009]      FIG. 2  is a partial exploded perspective view of a foot assembly of  FIG. 1 . 
           [0010]      FIG. 3  is a cross-sectional view of the foot assembly of  FIG. 1  taken along the line  3 - 3  illustrating a nozzle assembly in an engaged position during a rearward cleaning stroke. 
           [0011]      FIG. 4  is a cross-sectional view of the foot assembly of  FIG. 1  taken along the line  3 - 3  illustrating a nozzle assembly in a retracted position during a forward cleaning stroke. 
           [0012]      FIGS. 5A and 5B  are schematic views of the foot assembly of  FIG. 1  illustrating the height of a forward portion of the foot assembly relative to a surface to be cleaned during a forward and rearward cleaning stroke, respectively. 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    The invention generally relates to an apparatus for cleaning a surface and more specifically to a wet extractor. Referring to the figures, and in particular to  FIGS. 1 and 2 , an upright extractor  10  can comprise a foot assembly  12  having a pair of wheels  13  located at a rear portion of the foot assembly  12  and a handle assembly  14  pivotably mounted to the foot assembly  12  for directing the extractor  10  across a surface to be cleaned. The upright extractor  10  can be any suitable type of extractor and can comprise one or more features and operations common in extractors, such as those described in U.S. Pat. No. 6,131,237 to Kasper et al. and U.S. Patent Publication No. 2007/0226943 to Lenkiewicz et al. Such well-known features and operations will not be described in detail herein, except as otherwise necessary for a complete understanding of the invention. While the invention is described in the context of the upright extractor  10 , it is within the scope of the invention for any suitable type of extraction device to be used. 
         [0014]    Referring now to  FIG. 2 , the upright extractor  10  can comprise a fluid delivery system for storing and delivering a cleaning fluid to the surface to be cleaned and a fluid recovery system for extracting and storing the dispensed cleaning fluid and debris from the surface to be cleaned. The components of the fluid delivery system and the fluid recovery system can be supported by either or both the foot assembly  12  and the handle assembly  14 . In the illustrated embodiment, the components are primarily supported by the foot assembly  12 . 
         [0015]    The fluid delivery system comprises a fluid supply tank  16  for storing a supply of cleaning fluid, a fluid distributor  18  for depositing fluid onto the cleaning surface, and a fluid conduit (not shown) between the fluid supply tank  16  and the fluid distributor  18 . Various combinations of optional components can be incorporated into the fluid delivery system such as a conventional fluid pump, a heater, or fluid control and mixing valves as is commonly known in the art. 
         [0016]    Still referring to  FIG. 2 , the fluid recovery system can comprise an extraction path in the form of a suction nozzle  22  extending towards a surface to be cleaned, a recovery tank  24  and a working air conduit  26  in fluid communication with the suction nozzle  22  and the recovery tank  24 . The fluid recovery system can also comprise a motor/fan assembly  28  in fluid communication with the recovery tank  24  and configured to generate a working airflow to draw liquid and entrained debris through the suction nozzle  22  and into the recovery tank  24 . 
         [0017]    Referring now to  FIGS. 2 and 3 , a pair of conventional rotating agitators  30  can be rotatably mounted beneath the foot assembly  12  within a brush chamber  31 . The agitators  30  can be mounted between a pair of brush arms  32  pivotably mounted to the foot assembly  12  by a brush arm pivot  33 . The angular rotation of the brush arm  32  about the corresponding brush arm pivot  33  can be limited by bosses (not shown) protruding from within the brush chamber  31 . Alternatively, the agitators  30  can be rotatably mounted between vertically fixed bearings (not shown) secured within the brush chamber  31 . The agitators  30  can be operably connected to a drive motor (not shown) via a conventional timing belt (not shown) for agitating the surface to be cleaned as is commonly known in the art. It is also within the scope of the invention for the extractor  10  to include any number of rotating agitators and/or a fixed agitator assembly. 
         [0018]    The suction nozzle  22  can comprise a first nozzle portion  35  fluidly coupled with the working air conduit  26  and a nozzle extension  36  that can selectively fluidly couple the first nozzle portion  35  with a surface to be cleaned. The first nozzle portion  35  can have a pair of opposing front and rear walls  42  and  44 , respectively. The first nozzle portion  35  can be fixed to the foot assembly  12  through an attachment tab  46  extending from an upper portion of the rear wall  44 . The tab  46  can be secured to a mating pocket  48  on the foot assembly  12  via a mechanical fastener  50 , such as a screw or pin, or any suitable non-mechanical fastener, such as an adhesive or weld, for example. The first nozzle portion  35  can also be secured to the foot assembly  12  via retention hooks  52  that protrude upwardly from the end of a pair of legs  54  provided at the lateral sides of the first nozzle portion  35 . The hooks  52  can be configured to be received within mating slots  56  formed in a forward portion of a side wall of end caps  58  that are secured to the foot assembly  12  on either side of the brush chamber  31 . 
         [0019]    The nozzle extension  36  can comprise a pair of opposed front and rear walls  62 ,  64  defining a nozzle extension inlet  66  that can be selectively moved adjacent to a surface to be cleaned and a nozzle extension outlet  68 . The nozzle extension  36  can have any suitable length for engaging a surface to be cleaned. Spaced upper hinge tenons  70  can protrude from the rear wall  44  of the first nozzle portion  35  ( FIG. 3 ) and are configured to be received within slots  72  formed between lower hinge tenons  74  that can protrude outwardly from the rear wall  64  of the nozzle extension  36 . The upper and lower hinge tenons  70 ,  74  can be configured to interlock such that central bores  76  within each lower hinge tenon  74  and central bores (not shown) within each upper hinge tenon  70  can be axially aligned for receiving a hinge pin  78 . The upper and lower hinge tenons  70 ,  74  are configured such that they can rotate about the hinge pin  78  when the hinge pin  78  is received by the central bores of the upper and lower hinge tenons  70 ,  74 , thus forming a pivot bearing  80  between the first nozzle portion  35  and the nozzle extension  36 . The pivot bearing  80  permits the nozzle extension  36  to pivot with respect to the first nozzle portion  35 . The hinge pin  78  can be retained in place by a knurled end (not shown) that is press fit within a pocket (not shown) in the first nozzle portion  35 . Alternatively, the hinge pin  78  can be retained in place with a mechanical fastener, heat stake, adhesive, or other conventional fastener. 
         [0020]    Referring now to  FIGS. 3 and 4 , one or more of the lower hinge tenons  74  can have a rotation limiter  82  protruding from an outer barrel portion of the lower hinge tenon  74  to limit the degree of rearward rotation of the extension nozzle  36 . The rotation limiters  82  can comprise a plurality of short ribs that are configured to contact the rear wall  44  of the first nozzle portion  35  when the nozzle extension  36  is pivoted rearwardly to a retracted position during a forward cleaning stroke as illustrated in  FIG. 4 . For example, the rotation limiters  82  can limit the rotation angle to a maximum angular range of 15-70 degrees from vertical, which can promote pivoting of the nozzle extension  36  forward into the engaged position during a backward cleaning stroke as shown in  FIG. 3 . 
         [0021]    As illustrated in  FIG. 3 , when the nozzle extension  36  is in the engaged position in which the nozzle extension inlet  66  is in fluid communication with a surface  84 , the nozzle extension outlet  68  can also be in fluid communication with a first nozzle portion inlet  86  of the first nozzle portion  35 . The first nozzle portion  35  can also be provided with a first nozzle portion outlet  88  in fluid communication with the working conduit  26 . In this manner, the first nozzle portion  35  and the nozzle extension  36  can define a fluid flow path  90  from the surface  84  to the working conduit  26 . 
         [0022]    The nozzle  22  can also be provided with a seal  92  to selectively seal the nozzle extension outlet  68  with the first nozzle portion inlet  86  when the nozzle extension  36  is engaged with the surface  84 , such as is illustrated in  FIG. 3 . The seal  92  can be affixed to the nozzle extension outlet  68  or, alternatively, the seal  92  can be affixed to the first nozzle portion inlet  86 . The seal  92  can be a resilient seal and can comprise an over-molded elastomeric bead that extends around the perimeter of the nozzle extension outlet  68  or the first nozzle portion inlet  86 . Alternative, non-limiting seal geometries are also contemplated, non-limiting examples of which include a plurality of beads having a semi-circular, oval, or triangular cross-section extending around the nozzle extension outlet  68  or the first nozzle portion inlet  86 , arcuate resilient flaps, or a pleated accordion bellows boot extending between the first nozzle portion  35  and the nozzle extension  36 . 
         [0023]    Alternatively, adhesive backed resilient foam seals can be coupled with the nozzle extension outlet  68  or first nozzle portion inlet  86  to provide the seal  92 . In yet another alternative configuration, the seal  92  can be eliminated altogether and replaced by downwardly chamfered faces formed around the nozzle extension outlet  68  that are configured to be selectively received within inwardly chamfered faces formed around the first nozzle portion inlet  86 . When the nozzle extension  36  is in its engaged position, the downwardly chamfered faces can seal against the inwardly chamfered faces and permit a fluid connection between the first nozzle portion  35  and the nozzle extension  36 . 
         [0024]    The nozzle  22  can also be provided with a second seal  93  to selectively seal the first nozzle portion outlet  88  with the working air conduit  26 . The seals  92 ,  93  between the working air conduit  26 , the first nozzle portion  35  and the nozzle extension  36  can be provided to minimize leakage from the fluid flow path  90  during an extraction process as fluid is extracted from the surface  84  through the nozzle extension  36  and the first nozzle portion  35 . It is also within the scope of the invention for the nozzle  22  to not comprise any seals. 
         [0025]    The nozzle extension  36  can also comprise a gliding surface  94  at least partially surrounding the extension nozzle inlet  66  and a cam surface  96  along at least a portion of the length of the rear wall  64 . The cam surface  96  can have any suitable shape, but is illustrated as having an upwardly radiused portion that extends from the rear wall  64  providing a curved leading edge during a rearward cleaning stroke. The cam surface  96  can facilitate movement of the lower nozzle segment over the surface being cleaned during the course of a rearward cleaning stroke of the extractor  10  ( FIG. 3 ). The curved leading edge of the cam surface  96  can also prevent the nozzle extension inlet  66  from catching or snagging on carpet fibers or bouncing across the cleaning surface. Alternatively, the cam surface  96  can be in the form of an upwardly chamfered wall. 
         [0026]    In operation, the upright extractor  10  can be prepared for use by filling the supply tank  16  with water and/or cleaning fluid and coupling it with the foot assembly  12 . A user can then connect the extractor  10  to a line power supply and actuate the power switch (not shown) to energize the motor/fan assembly  28 , agitator motor (not shown), as well as any additional optional components within the fluid delivery system such as optional pumps, valves, or a heater. The motor/fan assembly  28  can generate a working air flow that is drawn into the nozzle extension inlet  66  of the suction nozzle  22 , through the working air conduit  26 , into a recovery tank  24  where fluid and debris can be separated from the working air stream and deposited in the recovery tank  24 , and finally into the motor/fan assembly  28 . The working air stream can flow through the motor/fan assembly  28  and can be exhausted to atmosphere through conventional vents (not shown) in the foot assembly  12 . 
         [0027]    Referring now to  FIG. 4 , on a forward cleaning stroke, a user can push the handle assembly  14  to maneuver the foot assembly  12  forward along the surface  84 , as illustrated by arrow  98 . As the extractor  10  moves forward, a front edge of the front gliding surface  94  can engage the surface  84 , which can provide a force to cause the nozzle extension  36  to pivot rearward relative to the direction of travel of the extraction cleaner  10  about the pivot bearing  80 . As the nozzle extension  36  rotates rearward, the nozzle extension inlet  66  can rotate away from the surface  84 , disrupting the fluid flow path  90  between the nozzle extension outlet  68  and the nozzle first portion inlet  86 . Rotation of the nozzle extension  36  can also disconnect the nozzle extension outlet  68  from the first nozzle portion inlet  86 , disrupting the working air flow through the suction nozzle  22 , interrupting suction adjacent the surface  84  and therefore interrupting extraction of fluid and/or debris from the surface  84 . The rotation limiters  82  can contact the rear wall  44  of the first nozzle portion  35  when the nozzle extension  36  rotates away from the surface  84 , limiting the extent of rotation to the retracted position illustrated in  FIG. 4 . 
         [0028]    Cleaning fluid from the fluid supply tank  16  can be selectively dispensed onto the surface  84  through the fluid distributor  18  during the cleaning process when a user actuates a trigger (not shown) on the handle assembly  14 . The rotation of the nozzle extension  36  to its retracted position during the forward stroke can provide time for the dispensed cleaning fluid to dwell on the surface  84  while the agitators  30  agitate the surface  84  before the fluid is extracted through the nozzle  22  on the subsequent rearward stroke ( FIG. 3 ), which can enhance the cleaning performance. 
         [0029]    On a rearward cleaning stroke, as illustrated in  FIG. 3 , a user can pull the extractor  10  rearwardly along the surface  84 , as illustrated by arrow  99 . As the foot assembly  12  moves rearward, the front gliding surface  94  can engage the surface  84 , resulting in a forward rotation of the nozzle extension  36  about the pivot bearing  80  opposite the direction of travel of the extractor  10 . The nozzle extension inlet  66  can rotate forward until it is adjacent to the surface  84 , compressing the seal  92  between the nozzle extension outlet  68  and first nozzle portion inlet  86 . In this manner, the working air flow through the first nozzle portion  35  can be re-coupled with the nozzle extension  36 , thus restoring suction adjacent to the surface  84 . As the foot assembly  12  continues to move rearward, the cam surface  96  can glide along the surface and can prevent the nozzle extension inlet  66  from snagging the surface or creating undesirable bouncing or vibration of the nozzle extension  36  against the surface  84 . When the nozzle extension  36  is in the engaged position, fluid and/or debris can be extracted by the working air flow suction through the fluid flow path  90  within the suction nozzle  22  and into the recovery tank  24  where fluid and debris can be separated from the working air flow and deposited in the recovery tank  24  for later disposal. 
         [0030]      FIGS. 5A and 5B  schematically illustrate the change in height of the foot assembly  12  relative to the surface  84  that can occur when the extractor  10  is moved in a forward stroke and a rearward stroke. Referring to  FIG. 5A , when the nozzle extension  36  is in the retracted position during a forward stroke, the foot assembly  12  can rotate about the axis of the wheels  13  such that a front portion  102  of the foot assembly  12 , opposite the wheels  13 , is tilted toward the surface  84  providing a distance  104  between the surface  84  and front portion  102  of the foot assembly  12  that can vary depending on the length of the nozzle extension  36 . When the nozzle extension  36  is in the engaged position during a subsequent rearward stroke, as illustrated in  FIG. 5B , the foot assembly  12  can rotate about the axis of the wheels  13  such that the front portion  102  of the foot assembly  12  is tilted away from the surface  84  such that the distance  104  is greater than during the forward stroke. Because the agitators  30  are mounted to a pair of pivotable brush arms  32  ( FIG. 3 ), the agitators  30  can move relative to the foot assembly  12  such that they maintain at least some contact with the surface  84  even as the distance  104  between the surface  84  and the front portion  102  of the foot assembly  12  changes during a forward and rearward stroke. 
         [0031]    Because the agitators  30  can maintain contact with the surface  84  during both the forward and rearward strokes, when the nozzle extension  36  is in the engaged position, some of the weight of the front portion  102  of the foot assembly  12  can be shifted from the agitators  30  to the nozzle extension  36 , whereas when the nozzle extension  36  is in the retracted position, the weight of the front portion  102  of the foot assembly  12  can be shifted to the agitators  30 . In this manner, the pressure applied by the agitators  30  and nozzle extension  36  can be varied during forward and rearward strokes as the weight of the foot assembly  12  is shifted as the nozzle extension  36  moves between the retracted and engaged positions. Increased pressure applied by the agitators  30  during the forward stroke can enhance engagement of the agitators  30  with the surface  84  which can lead to improved cleaning performance. Furthermore, increased pressure applied by the nozzle extension  36  during a rearward stroke can enhance engagement of the nozzle extension inlet  66  with the surface  84  which can lead to improved fluid extraction and liquid recovery from the cleaning surface  84 . 
         [0032]    While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation. Reasonable variation and modification are possible within the scope of the forgoing disclosure and drawings without departing from the spirit of the invention which is defined in the appended claims. For example, the sequence of steps depicted in each method described herein is for illustrative purposes only, and is not meant to limit the disclosed methods in any way as it is understood that the steps may proceed in a different logical order or additional or intervening steps may be included without detracting from the invention.