Abstract:
A recovery system for use in a floor cleaning machine of the type including a dispensing system and a recovery system. The dispensing system configured for dispensing a liquid cleaning solution onto a floor surface to facilitate the removal of dirt from the floor surface. A recovery system configured for recovering cleaning solution and dirt from the floor surface thereby leaving a cleaned floor surface. The recovery system comprises a recovery tool movable over the floor surface. The recovery tool comprises a body including an interior suction chamber in fluid communication with a source of vacuum. At least one blade is secured to the tool body and depending therefrom for engagement with the floor surface to provide fluid communication between the suction chamber and the floor surface, whereby cleaning solution and dirt are suctioned from the floor surface. The blade is substantially rigid to inhibit deformation of the blade during operation of the floor cleaning machine and is movable relative to the tool body such that the blade remains substantially in engagement with the floor surface while moving relative to the tool body to adapt to contours in the floor surface.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates generally to an extraction machine used for cleaning floor surfaces with a cleaning liquid and then extracting the liquid from the floor, and more particularly to such an extraction machine comprising an improved cleaning liquid recovery tool. 
     In extraction machines of conventional design as shown in FIG. 1, a solution tank contained within the machine housing dispenses a liquid cleaning solution onto the floor surface to be cleaned, such as a carpet. The cleaning solution is typically a premixed solution comprised of water and a liquid or powder cleaning agent. One or more spray nozzles of the extraction machine spray cleaning solution onto the carpet. The scrub brush, rotatably driven by a brush motor, then works the cleaning solution into the carpet to lift dirt from the carpet, temporarily leaving a dirty solution within the carpet. 
     The machine is self-propelled or moved manually to pass over the dirty solution so that a vacuum tool mounted on the machine moves over the portion of the carpet worked by the scrub brush. The vacuum tool comprises a hollow body with two elongate blades extending from the bottom of the body in spaced, generally parallel relationship, so that each blade forms a rough seal with the carpet (FIG.  2 ). The vacuum tool provides a vacuum within a suction chamber, above the surface of the carpet, allowing the extraction of dirt and solution from the carpet. A vacuum pump driven by a vacuum motor creates a vacuum within a recovery tank, which communicates with the tool by means of a recovery line extending between the recovery tank and the tool. Suction created by the vacuum pump extracts the dirty cleaning solution from the carpet, resulting in a cleaned carpet. Dirty solution passes through the tool and recovery line into the recovery tank carried by the machine. 
     Conventional vacuum tool blades are formed from unitary pieces of hard material such as plastic. One disadvantage of using such a design is that when the blades encounter an uneven portion of the carpet, the blades lift from flatwise engagement with the carpet, creating air gaps and breaking the seal between the blades and the carpet. These air gaps degrade the effectiveness of the vacuum because they allow air to enter the suction chamber without extracting any dirty cleaning solution from the carpet. This increases how much cleaning solution residue remains in the carpet after cleaning, resulting in quicker resoiling of the carpet and longer drying time after cleaning. Another drawback of the conventional tool described above is the potential for damaging the tool should it strike a door threshold or other hard object. Damaging the recovery tool often further degrades the vacuum, exacerbating vacuum losses. Finally, a damaged vacuum blade on a conventional extraction machine requires replacing the entire blade, which is not cost effective when only a portion is damaged. 
     SUMMARY OF THE INVENTION 
     Among the several objects and features of an extraction machine of the present invention may be noted the provision of a recovery system that maintains a tight seal with the floor surface being cleaned over uneven portions of the floor surface; the provision of such a recovery system that improves the strength and effectiveness of the vacuum created beneath the tool; the provision of such a recovery system that more effectively removes dirty cleaning solution from a cleaning surface; the provision of such a recovery system that reduces the drying time of the floor surface; the provision of such a recovery system that reduces the likelihood of damage to the system when encountering door thresholds or other objects; the provision of such a recovery system that allows for easy replacement of damaged or worn system parts, including blade holders, blades and related parts; and the provision of an improved blade assembly and replacement blades therefor. 
     Generally, a recovery system of the present invention comprises a recovery tool movable over a floor surface. The tool has a body including an interior suction chamber in fluid communication with a source of vacuum. At least one elongate blade assembly is secured to the tool body and comprises a blade engageable with the floor surface to provide a seal between the blade and the floor surface. Cleaning solution and dirt are suctioned from the floor surface by the source of vacuum. The blade is substantially rigid to inhibit deformation of the blade during operation of the floor cleaning machine and is movable relative to the tool body such that the blade remains substantially in engagement with the floor surface while moving relative to the tool body to adapt to contours in the floor surface. 
     In a second embodiment of the present invention, a recovery system comprises a recovery tool comprising a blade generally as set forth above. The blade mounts resiliently on the tool for floating movement relative to the tool body so that the blade remains substantially in engagement with the floor surface while moving relative to the tool body to adapt to floor surface contours. 
     In a third embodiment of the present invention, a recovery system comprises a recovery tool comprising a blade generally as set forth above. The blade further comprises a plurality of blade segments independently secured to and resiliently mounted on the tool for floating movement of the individual segments with respect to the body and each other, further enabling the segments to conform to uneven floor surfaces. 
     The present invention is also directed to a blade assembly for use in a floor cleaning machine of the type including a dispensing system configured for dispensing a liquid cleaning solution onto a floor surface to facilitate the removal of dirt from the floor surface and a recovery system configured for recovering cleaning solution and dirt from the floor surface thereby leaving a cleaned floor surface. The blade assembly comprises an elongate blade having an upper portion and a floor engaging lower portion, and a holder for holding the blade for movement of the blade between an extended position and a retracted position. The assembly also includes a spring system mounted on the holder and engageable with the upper portion of the blade for biasing the blade to an extended position. Movement of the blade over an uneven contour of the floor surface moves the blade from the extended position upwardly toward a retracted position against the bias of the spring system to accommodate the uneven contour while maintaining a sealing engagement between the floor surface and the blade. 
     Another aspect of the present invention is directed to a blade which can be used on a floor cleaning machine of the type described above. The blade has an upper portion adapted to be held by a blade holder of the machine, and a lower portion engageable with the floor surface to be cleaned. The upper portion of the blade has an upward facing surface configured for engagement by a spring system on the blade holder to bias the blade in a downward direction toward the floor surface. The upper portion also has a downward facing surface engageable with the blade holder for limiting the downward movement of blade toward a floor surface. 
     The present invention is also directed to a cleaning machine comprising a recovery tool generally as set forth above. The cleaning machine is of the type comprising a main housing and at least one spray nozzle mounted on the main housing for spraying a cleaning solution onto a floor surface. The machine comprises a brush housing mounted on the main housing that includes at least one scrub brush for agitating a floor surface. 
     Other objects and features will become in part apparent and in part pointed out hereinafter. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side elevation and partial section of a prior art extraction machine as may be conveniently used with the present invention; 
     FIG. 2 is a front elevation of a recovery tool of the carpet cleaning machine of FIG. 1; 
     FIG. 3 is a front elevation of a recovery tool of the present invention, with a portion broken away to reveal internal construction; 
     FIG. 4 is a side elevation of the recovery tool of FIG. 3, with a portion broken away to reveal internal construction; 
     FIG. 5 is a fragmentary, side elevation of the recovery tool of FIG. 3 with a portion broken away to reveal internal construction shown in partial section; 
     FIG. 5A is a second view of the recovery tool of FIG. 5 with a blade segment in a retracted position; 
     FIG. 6 is a fragmentary, front elevation and partial section of the recovery tool of FIG. 3 with a portion broken away to reveal internal construction; 
     FIG. 7 is a fragmentary, front elevation and partial section with a portion broken away to reveal internal construction of another embodiment of the recovery tool of the present invention; and 
     FIG. 8 is a fragmentary, side elevation and partial section with a portion broken away to reveal internal construction of yet another embodiment of the recovery tool of the present invention. 
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views of the drawings. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIG. 1, a conventional extraction machine for cleaning floor surfaces, such as carpeting, is indicated in its entirety by the reference numeral  21 . The extraction machine  21  comprises a main housing, indicated generally at  23 , mounted on wheels  24  so an operator can readily move the machine. A motor (not shown) may also drive the wheels  24  to self-propel the extraction machine  21 . A handle  25  mounted at the rear of the machine  21  gives the operator a convenient means for guiding and maneuvering the extraction machine during operation. Suitable controls (not shown) on the handle  25  control various operating components of the machine  21 . The operator pulls the handle  25  to move the machine  21  in a rearward direction, indicated by arrow A. 
     The main housing  23  has a top wall  26 , a bottom wall  27 , a front wall  29 , a rear wall  31  and side walls (not shown), portions of which define a solution tank  32 . The main housing  23  also defines a cavity  33  that contains the operating components of the extraction machine  21 . Plates  35  partially define the bottom wall  27  of the main housing  23  (one such plate being shown in FIG.  1 ). The plates  35  are spaced apart in close relationship with each other to define air gaps (not shown) between the plates. These gaps allow ambient air external to the main housing  23  to enter the cavity  33 . 
     The solution tank  32  holds a supply of liquid cleaning solution  43  for cleaning the carpet. A solution pump  44  communicates with the solution tank  32  to deliver cleaning solution  43  from the tank to a feed line  45 . A brush housing  46  mounts on the underside of the main housing  23 . A locator pin  52  releasably secures the brush housing  46  at a predetermined height above the carpet. The operator may adjust the height of the brush housing  46  according to the depth of the carpet to be cleaned. The feed line  45  extends through the brush housing  46  to a manifold (not shown) to direct cleaning solution  43  to one or more spray nozzles  51  spaced laterally across the bottom of the brush housing for delivering cleaning solution onto the surface to be cleaned. A second set of nozzles  54  placed beneath the front of the main housing  23  directs additional cleaning solution  43  onto the surface to be cleaned. 
     A rotary scrub brush  47  mounted for rotation within the brush housing  46  has bristles  49  which contact the surface to be cleaned. The scrub brush  47  is near the spray nozzles  51  to encourage interaction between the scrub brush and the cleaning solution  43 . The scrub brush  47  is driven by a brush motor  53  located in a compartment  55  in the brush housing  46  to effect a scrubbing action with the cleaning solution to remove dirt within the carpet. As dirt is removed from the surface, it clings to the cleaning solution, leaving dirty solution on the surface of the carpet. The second set of nozzles  54  dispenses additional cleaning solution onto the surface after the brush  47  passes over a particular portion of the surface to further attract dirt before suctioning of the dirty solution from the surface. 
     A vacuum pump  59  is mounted within the cavity  33  directly below a solution recovery tank  61  seated in an opening  63  in the top wall  26  of the housing  23 . A vacuum motor  65 , such as an electric drive motor, mounted beneath the vacuum pump  59  drives the pump and an associated suction fan (not shown). The vacuum pump  59  has an intake (not shown) which communicates with the inside of a hollow air cap  69  sealingly attached to or integrally formed with the bottom wall of the recovery tank. A suction pipe  73  extends up from this cap  69  to a location adjacent the top of the recovery tank  61 . Operation of the vacuum pump  59  and associated suction fan draws air from the recovery tank  61  to create a vacuum in the tank. The vacuum pump  59  has an exhaust  75  for exhausting air from the suction fan. A liquid level sensor  77  senses the level of dirty solution  57  within the recovery tank  61 . This sensor  77  is operable to shut off the extraction machine  21  before the solution level reaches the upper end of the suction pipe  73 . 
     A recovery tool  79  mounts on the underside of the main housing  23  and extends between the housing and the carpet so that the tool and wheels  24  combine to support the extraction machine  21  in an upright position. The tool  79  has a centrally located opening  80  extending upwardly therethrough. This opening  80  is connected by means of a flexible recovery line or hose  81  to a rigid fill tube  83  extending up into the recovery tank  61 , the upper end of the tube being at a level higher than that of the level sensor  77 . As the tool  79  passes over the surface being cleaned, the vacuum in the recovery tank  61  is sufficient to extract dirty solution  57  from the carpet through the opening  80  in the tool and up through the hose  81  and the fill tube  83  for delivery to the recovery tank  61 . A drain line  85  with a closure  87  drains dirty solution  57  from the recovery tank  61  as needed. 
     With reference to FIG. 2, the tool body  89  of the conventional extraction machine recovery tool  79  is generally elongate in shape, with a pair of straight, rigid blades  91  mounted beneath the body in parallel spaced-apart relationship. The blades  91  are intended to engage and form a rough seal with the carpet, so that the vacuum in the recovery tank  61  creates a vacuum between the blades for extracting dirty solution  57  from the carpet. However, the rigidity of the blades  91  can hamper performance of the machine  21  as the blades pass over the ridges and valleys in the carpet. As shown in FIG. 2, a carpet ridge can lift the tool  79  from the carpet, creating air gaps G between the blades  91  and carpet. The gaps G allow outside air to pass freely beneath the blade  91  (instead of being forced through the carpet), thus lessening the effectiveness of the vacuum and slowing dirty solution removal. 
     Referring now to FIGS. 3 and 4, a recovery tool of the present invention for extracting cleaning solution from a floor surface, such as a carpet, is indicated in its entirety by reference numeral  101 . The recovery tool  101  is shown and described herein in connection with an extraction machine, such as the conventional extraction machine  21  illustrated in FIGS. 1 and 2. The recovery tool  101  comprises a hollow tool body  103  defined by a front wall  105 , a rear wall  107 , a top wall  108  and two end walls  109  sloping laterally outward from the top wall to the respective bottoms of the front and rear walls. The bottom of the tool body  103  is open, and the tool body is movable over the floor surface for engaging the floor surface and suctioning cleaning solution and dirt. The opening  80  in the top wall  108  of the tool body  103  connects to a hose seat  117  and to the flexible hose  81  for fluid communication with the recovery tank  61 . The hollow tool body  103  further comprises a suction chamber  11  (FIG. 4) defined by an interior panel  118 , shown in dashed (hidden) lines in FIG. 4, opposing partitions  119  (FIG. 3) and the front wall  105 . The suction chamber  111  is additionally in fluid communication with the source of vacuum. The interior panel  118  extends laterally between the end walls  109  and slopes up from the bottom of the tool body at an angle toward the top wall  108 , the opening  80  in the top wall being disposed intermediate the interior panel and the front wall  105 . Opposing partitions  119  extend between the interior panel  118  and the front wall  105  of the tool body  103 . The suction chamber  111  suctions dirty solution from the floor surface into the recovery tool  101 . 
     In the illustrated embodiment, the interior panel  118  slopes upward and rearward from the bottom of the tool body  103  to the top wall  108 . However, the interior panel  118  may be oriented otherwise without departing from the scope of this invention. As illustrated, the partitions  119  are generally arcuate, curving from the end walls  109  up toward the opening  80  for directing dirty solution  57  in the suction chamber  111  to flow up through the opening  80  to the recovery tank  61 . However, it is contemplated that the partitions  119  may be other than arcuate, such as straight, or may be omitted, without departing from the scope of this invention. The surfaces of the front wall  105 , interior panel  118  and partitions  119  defining the suction chamber  111  are smooth to promote flow of the dirty cleaning solution  57  up to the opening  80 . 
     The recovery tool  101  is suspended from the extraction machine  21  for engagement with the floor surface. Two attachment ears  120  extend from the top wall  108  of the recovery tool  101  (FIGS.  3  and  4 ). The attachment ears  120  are engageable with a horizontal support bracket  121  through pin connections  122 . The bracket  121  is mounted on the extraction machine  21 , allowing the recovery tool  101  to pivot relative to the bracket about the pin connections  122 . During use, the recovery tool  101  is preferably oriented in a vertical position as depicted in FIG.  4 . To orient and hold the recovery tool  101  in a substantially vertical position, a positioning turnbuckle is generally indicated at  123 . The turnbuckle  123  includes a rotatable adjustment shaft  123   a , two locknuts  124  threadably connected to the shaft and two ball joints  125  threadably connected to the shaft. The ball joints  125  pivotably mount on flanges  126  extending from the recovery tool  101  and the bracket  121 . To alter the length of the turnbuckle  123 , both locknuts  124  must be rotated about the adjustment shaft  123   a  so that they move away from the ball joints  125 , unlocking the adjustment shaft so that it may freely rotate. The ends of the adjustment shaft  123   a  are oppositely threaded, so that rotating the shaft in one direction pulls both ball joints  125  inward, shortening the turnbuckle  123 , while rotating the shaft in the other direction pushes both ball joints outward, lengthening the turnbuckle. The locknuts  124  may then be rotated about the adjustment shaft  123   a  to seat against the ball joints  125 , holding the adjustment shaft in a specific orientation and setting the turnbuckle  123  length. As the turnbuckle  123  length changes through the previous steps, the orientation of the recovery tool  101  changes with respect to the bracket  121 . 
     The recovery tool  101  further comprises a pair of longitudinally extending, elongate blade assemblies, each generally designated  127 , secured to the bottom of the tool body  103  and depending therefrom in spaced, generally parallel relationship with each other to define a suction inlet  129  (FIG. 5) at the bottom of the recovery tool  101  for extracting dirty solution from the floor surface into the suction chamber  111 . In the illustrated embodiment, the blade assemblies  127  are further defined as leading blade assembly  127 L and trailing blade assembly  127 T. The leading blade assembly  127 L angles slightly from vertical while the trailing blade assembly  127 T is oriented vertically. However, either assembly  127  may be oriented vertically or at an angle while remaining within the scope of this invention. 
     Each blade assembly  127  comprises an elongate blade holder  133  secured to the tool body  103  along the length of the tool body. As described further below, each blade holder  133  is adapted for holding a blade  135  comprising multiple individual blade segments  135   s  in engagement with the floor surface being cleaned. Six blade segments  135   s  are illustrated in FIG.  3 . However, any number of blade segments  135   s , including a single blade segment, is contemplated as within the scope of this invention. Referring to FIGS. 5,  5 A and  6 , each blade holder  133  comprises an elongate hollow housing formed by a C-shaped channel member  139  having a top wall  139   a , a bottom wall  139   b , a rear side wall  139   c  and a front side wall  139   d . A removable cover  141  is positioned over an opening  143  in the front side wall  139   d  of the channel member for closing the opening. The cover  141  of the illustrated embodiment is removable for maintaining or replacing blade segments  135   s . A slot  145  extends longitudinally within the bottom wall  139   b  of the channel member  139  for purposes that will become apparent. In the preferred embodiment, suitable fastening methods mount the blade holders  133  to the tool body. Alternatively, the blade holders  133  may be integrally formed with the tool body. 
     The blade segments  135   s  seat within a respective blade holder  133  in end-to-end generally abutting relationship with each other, such that the ends of adjacent blade segments abut one another with no significant gaps between the segments. As shown in FIG. 5, the blade segments  135   s  are generally rectangular in cross-section, each including an upper portion  147  sized larger than the width of the slot  145  in the bottom wall  139   b  of the channel member  139  to inhibit the segment from falling out of the blade holder  133 , and a lower portion  149  sized to extend down through the slot in the channel member for positive engagement with the floor surface being cleaned. The blade segments  135   s  are preferably constructed from a hard, plastic material or other suitably rigid materials exhibiting good wear resistance properties to inhibit deformation and wearing of the blade segments as the segments engage the floor surface during operation. One particularly preferred material from which the blade segments  135   s  are constructed is Glass Filled Nylon. 
     Referring again to FIG. 5, each blade segment  135   s  is independently secured to and resiliently mounted in the blade holder  133  for floating movement relative to the holder, the tool body  103  and the other segments of the same blade  135 . Each blade segment is movable between an extended position (FIG. 5) in which the upper portion  147  of the segment seats against the bottom wall  139   b  of the channel member  139  of the blade holder  133 , and a retracted position (FIG. 5A) in which the blade segment is pushed up further into the channel member. The blade segments  135   s  are biased toward their extended position by coil compression springs  157  (broadly, a spring member) disposed in the channel member  139  between the upper portion  147  of the blade segments and the top wall  139   a  of the channel member. In the illustrated embodiment of FIGS. 3-6, the springs  157  seat against the top wall  139   a  of the channel member  139 . It is contemplated, however, that the springs  157  may seat within indents or recesses  159  in the upper portions  147  of the blade segments  135   s , as shown in FIGS. 6 and 8 and discussed later herein. Alternately, the springs may fit over spring seats, such as posts (not shown), extending up from the upper portions  147  of the blade segments, for more positive positioning of the springs in the blade holder  133 . Springs  157  can take forms other than coil compression springs. 
     In operation, an extraction machine  21  incorporating the recovery tool  101  of the present invention is operated to move over a floor surface, such as carpeting, along a desired cleaning path. As the extraction machine  21  passes over a section of carpet being cleaned, it applies cleaning solution  43  to the carpet. The brush  47  then works the cleaning solution  43  into the carpet, loosening dirt particles that become suspended in the cleaning solution. As the machine  21  is moved further rearward in the direction of cleaning, it applies additional cleaning solution  43  to the carpet to ensure that the dirt particles are suspended within the solution, forming a dirty solution. Finally, the recovery tool  101  of the present invention passes over the portion of the carpet being cleaned. The vacuum pump  59  creates a vacuum within the recovery tank  61 , thereby providing a vacuum in the suction chamber  111  of the tool body  103  of the recovery tool  101 . As the recovery tool  101  passes over the carpet, the blade segments  135   s  are biased to their extended position to press down against the carpet to form a rough seal between the blade  135  and the carpet beneath the suction chamber  111 . Dirty solution is then suctioned from the carpet up into the tool body  103  and directed by the partitions  119  of the tool body to flow up through the opening  80  in the top wall  108  of the tool body for flowing to the recovery tank  61 . 
     When the recovery tool  101  passes over a section of carpet having a ridge, such as when an object is beneath the carpet, the carpet is otherwise warped or wrinkled or the floor beneath the carpet is otherwise not flat, the blade segments  135   s  engaging the ridged section of the floor surface move against the bias of the springs  157  in the blade holders  133  toward their retracted positions (FIG.  5 A). Blade segments  135   s  not engaging the ridge in the floor surface remain in their extended position pressed down against the floor surface to reduce the size of any air gaps between the floor surface and the blade  135 . Once the recovery tool  101  moves past the ridged portion of the floor surface, the springs  157  force the retracted blade segments  135   s  back toward their extended position. The independent movement of the blade segments  135   s  relative to the tool body and to one another ensures that the blade  135  remains substantially in engagement with the floor surface along the length of the blade as the recovery tool  101  is moved over contours in the floor surface. 
     Referring now to FIG. 7, another embodiment of a recovery tool  161  of the present invention is shown. A leaf spring  163  (broadly, a spring member) is secured to the top wall  139   a  of each channel member  139  on the inside of the member in a position in which the spring is in biasing engagement with the top of respective blade segments  135   s  in the channel to bias the blade segments toward their extended positions. In the illustrated embodiment, a unitary strip  168  of resilient, metallic material extends generally the full length of the blade assembly  127  and engages each of the blade segments  135   s . The leaf spring  163  is mounted in the blade holder  133  above the blade segments  135   s  by a series of posts  171  extending down from the top wall  139   a  of the channel member  139  through holes  173  in the spring spaced at intervals generally corresponding to the length of the blade segments. The portions of the springs  163  between the posts  171  curve downward for resilient engagement with the respective blade segments  135   s  to urge the segments toward their extended positions. It is also contemplated that individual leaf springs (not shown), each individually mounted on the blade holder  133  above a respective blade segment  135   s , may be used instead of a unitary strip  168  without departing from the scope of this invention. 
     In another embodiment shown in FIG. 8, the blade holder  133  is substantially the same as the previous embodiments, except that the holder  133  comprises a tubular channel member  175  of unitary construction (e.g., without a separate cover  141  of the embodiment of FIGS.  3 - 6 ). To assemble this embodiment, the blade segments  135   s  are inserted through an open end of each channel member  175 . End caps (not shown) are removably fitted on the open ends of the blade holder  133  to retain the blade segments  135   s  within the blade holder. Should one or more blade segments  135   s  become damaged or worn from use, removal of the end caps permits replacement of the blade segments. 
     In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained. The provision of multiple blade segments  135   s , each capable of independent movement relative to the tool body  103  and relative to other segments, allows the blade segments to conform to the contours of the floor surface being cleaned. Biasing the individual blade segments  135   s  down against the floor surface promotes sealing of the vacuum in the suction chamber  111  of the tool body. This reduces the risk of air gaps forming between the blade  135  and the floor surface being cleaned, thereby maintaining the strength of the vacuum and promoting extraction of dirty solution  57  from the floor surface even as the recovery tool  79  passes over uneven sections of the floor surface. By increasing the amount of dirty solution  57  suctioned from the floor surface, the surface is less likely to become resoiled, since little residual fluid remains on the floor surface to attract dirt. 
     When introducing elements of the present invention or the preferred embodiment(s) thereof, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. 
     As various changes could be made in the above without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.