Patent Publication Number: US-7908705-B2

Title: Bare floor cleaner

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional of U.S. patent application Ser. No. 10/711,117, filed Aug. 25, 2004, now U.S. Pat. No. 7,823,250, issued Nov. 2, 2010, which claims the benefit of U.S. Patent Application No. 60/521,254, filed Mar. 19, 2004, and U.S. Patent Application No. 60/498,094, filed Aug. 26, 2003. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a bare floor cleaner. In one aspect, the invention relates to a bare floor cleaner that is capable of wet pickup through a first nozzle opening with the aid of a squeegee. In another aspect, the invention relates to a bare floor cleaner that is capable of wet scrubbing with an agitator, with or without wet pickup. In yet another aspect, the invention relates to a bare floor cleaner that is capable of dry pickup through a second nozzle opening. 
     2. Description of the Related Art 
     The common procedure of cleaning a bare floor surface, such as tile, linoleum, and hardwood floors, involves several steps. First, dry or loose dust, dirt, and debris are removed, followed by applying liquid cleaning solution to the surface either directly or by means of an agitator. Motion of the agitator with respect to the bare surface loosens the remaining dirt. If the agitator is absorbent, it will remove the dirt and collect a portion of the soiled cleaning solution from the floor; otherwise, the dirt and soiled cleaning solution must be removed by another means. Finally, the remaining soiled cleaning solution on the surface is commonly left to air dry, and the duration of time required for the bare surface to completely dry depends on the amount of residual solution on the floor. During this period, it is best to avoid foot traffic in the area because dirt and debris easily adheres to a wet surface. 
     Washing a bare floor is commonly accomplished with multiple cleaning tools. For example, the first step of removing dry particles most often employs a conventional broom and dustpan. However, when sweeping dirt from a pile into the dustpan, it is difficult to transfer the entire pile. As a result, a portion of pile tends to remain on the floor. Additionally, a user must bend over to hold the dustpan in place while collecting the dirt pile. Such motion can be inconvenient, difficult, and even painful for some users. Dust cloths can also be used, but large dirt particles do not sufficiently adhere thereto. Another option is vacuuming the dry dirt, but most homes are equipped with vacuum cleaners that are designed for use on carpets and can damage bare surfaces. 
     Tools for applying and/or agitating cleaning solution have similar deficiencies. The most common cleaning implement for these steps is the traditional sponge or rag mop. Mops are capable of loosening dirt from the floor and have excellent absorbency. When the mop requires cleaning solution, it is placed in a bucket to soak up warm cleaning solution and returned to the floor. Each time, the mop is usually placed in the same bucket, and after several repetitions, the cleaning solution becomes dirty and cold. As a result, spent cleaning solution is used to remove dirt from the bare surface. Furthermore, movement of the mop requires physical exertion, and the mop head wears with use and must be replaced periodically. A textured cloth can also be used as an agitator, but it also requires physical exertion and regular replacement. Additionally, cloths are not as absorbent as mops and, therefore, can leave more soiled cleaning solution on the floor. 
     Household cleaning devices have been developed to eliminate the need for multiple cleaning implements for washing a bare floor and alleviate some of the problems described above that are associated with the individual tools. Such household devices are usually adapted for vacuuming or sweeping dry dirt and dust prior to application of cleaning solution, applying and agitating the cleaning solution, and, subsequently, vacuuming the soiled cleaning solution, thereby leaving only a small amount of cleaning solution on the bare surface. Common agitators are rotating brushes, rotating mop cloths, and stationary or vibrating sponge mops. A good portion of the multifunctional cleaning devices utilizes an accessory that is attached to the machine to convert between dry and wet cleaning modes. Others are capable of performing all of the functions without accessories but have complex designs and features that can be difficult and confusing to operate. 
     Examples of multi-functional bare floor cleaners are disclosed in U.S. Pat. Nos. 2,622,254 and 6,101,668 and in U.S. Patent Application Publication Nos. 2003/0051301, 2003/0051306, 2003/0051308, 2003/0051309, and 2003/00513010. U.S. Pat. No. 2,622,254 discloses an apparatus for cleaning bare and carpeted floors and comprises several independently adjustable cleaning implements, such as a squeegee attached to a suction pipe, a scrubbing roll, and a sweeping roll. The apparatus can accomplish wet pickup through the suction pipe, wet scrubbing by means of the scrubbing roll, and dry pickup with a dust collecting nozzle disposed adjacent the sweeping roll. 
     The above listed family of patent application publications discloses a bare floor cleaner having independently adjustable nozzle and brush assemblies. The nozzle assembly comprises a single nozzle opening that is surrounded by an overmolded squeegee and through which both wet and dry debris can enter. The cleaner operates in a wet pickup mode with the nozzle assembly in contact with the surface to be cleaned. The nozzle assembly is raised to a position above the surface to be cleaned for operation in a dry pickup mode. 
     U.S. Pat. No. 6,101,668 is an example of a cleaner that can accomplish all the steps required to clean a bare floor with the assistance of an attachment. The cleaner has a cleaning head equipped with a nozzle having squeegees on the front and rear sides thereof and a vertically adjustable scrubbing pad through which cleaning solution can be dispensed. When a cover is attached to the bottom of the cleaning head, the entire cleaning head, including the squeegees, nozzle, and pad, are raised from the floor to permit dry pickup. 
     SUMMARY OF THE INVENTION 
     The invention relates to a floor cleaner capable of cleaning both wet and dry floor surfaces and comprises a base having a dry suction opening and a wet suction opening, a handle pivotally connected to the base, a recovery tank mounted to one of the handle and the base, a working air conduit extending from each of the dry suction opening and the wet suction opening to the recovery tank, a motor/fan assembly mounted to one of the handle and the base and adapted to create a working air flow in the working air conduit from at least one of the dry floor suction opening and the wet floor suction opening and to the recovery tank and a diverter mounted in the working air conduit and movable between a dry suction position and a wet suction position for selectively at least partially blocking working air flow from the dry suction opening and the wet suction opening, respectively, to the recovery tank. According to the invention, an actuator is mounted on at least one of the handle and the base and operably connected to the diverter for selectively positioning the diverter in the dry suction position and the wet suction position. 
     In one preferred embodiment of the invention, the actuator is adapted to simultaneously position the diverter and the agitator in preselected positions. 
     In another preferred embodiment of the invention, an agitator is movably mounted to the base for movement between a first position wherein the agitator is adapted to agitate a surface to be cleaned and a second position wherein the agitator is spaced from the surface to be cleaned for selectively agitating the floor surface. The actuator is operably coupled to the agitator for selectively positioning the agitator in the first position and the second position. 
     Preferably, the actuator is adapted to simultaneously position the diverter and the agitator in preselected positions. A control element is mounted between the actuator and the diverter and between the actuator and the agitator for moving the diverter and agitator into a first mode wherein the diverter is in the dry suction position and the agitator is in the second position, a second mode wherein the diverter is in the wet suction position and the agitator is in the first position and a third mode wherein the diverter is in the wet suction position and the agitator is in the second position. Further, the control element is adapted to control movement of the diverter and agitator into a fourth operating mode wherein the diverter is in the dry position and the agitator is in the first position. 
     In an illustrative embodiment, the control element comprises a diverter cam member adapted to control the position of the diverter and an agitator cam member adapted to control the position the agitator. In this embodiment, the control element comprises a wheel with two sides. The diverter cam member and the agitator cam member are disposed on opposite sides of the wheel. The actuator can connected to the control element through a pull-pull cable assembly. In a preferred embodiment, the actuator is disposed on the handle. 
     In another illustrative embodiment, an agitator platform is pivotally mounted to the base and mounts the agitator and the control element is operatively connected to the agitator platform for selective positioning the agitator in the first and second positions. Further, the agitator is driven by an agitator motor that is mounted on the agitator platform. 
     In one preferred embodiment, the recovery tank is mounted on the handle and the motor/fan assembly is mounted on the handle above the recovery tank. Further, a carry handle mounted on the handle. 
     In another illustrative embodiment, a supply tank is mounted to the handle for storing a supply of cleaning fluid, a dispenser is mounted to the base for dispensing cleaning fluid onto the floor surface, a supply conduit extends between the supply tank and the dispenser and a heater is mounted in the supply conduit for heating the cleaning fluid as it flows from the supply tank to the dispenser. 
     Still further according to the invention, a floor cleaner capable of cleaning both wet and dry floor surfaces comprises a base having a dry suction opening and a wet suction opening adapted to remove debris from a surface to be cleaned, a handle is connected to the base, a recovery tank is carried by the handle and a working air conduit extends from each of the dry suction opening and the wet suction opening to the recovery tank A motor/fan assembly is mounted to one of the handle and the base and is adapted to create a working air flow in the working air conduit from at least one of the dry floor suction opening and the wet floor suction opening and to the recovery tank. A diverter is mounted in the working air conduit and is movable between a dry suction position and a wet suction position for selectively at least partially blocking working air flow from the wet suction opening and the dry suction opening, respectively, to the recovery tank. An actuator is mounted on the handle of the base and is operably connected to the diverter for selectively positioning the diverter in the dry suction position and the wet suction position. 
     In a preferred embodiment, the motor/fan assembly is mounted above the recovery tank on the handle. Further, the handle is pivotally connected to the base. 
     In an illustrative embodiment of the invention, an agitator is mounted to the base and is movable between a first position wherein the agitator contacts the floor surface and a second position wherein the agitator is spaced from the floor surface for selectively agitating the floor surface. The actuator is operably connected to the agitator for selectively positioning the agitator between the first position and the second position. 
     Preferably, the actuator can simultaneously position the diverter and the agitator in preselected positions. 
     Still further according to the invention, a floor cleaner capable of cleaning both wet and dry floor surfaces comprises a base for movement along a floor surface to be cleaned, a nozzle assembly mounted to the base and having a dry suction conduit with a dry suction opening at one end thereof adjacent to the floor surface and a wet suction conduit with a wet suction opening at one end thereof adjacent to the floor surface and different from the dry suction opening. A handle is connected to the base and a recovery tank mounted on one of the handle and the base. A working air conduit extends from each of the dry suction opening and the wet suction opening to the recovery tank. A motor/fan assembly is mounted to the handle or the base and is adapted to create a working air flow in the working air conduit from at least one of the dry floor suction opening and the wet floor suction opening and to the recovery tank. The wet suction conduit and the dry suction conduit are vertically juxtaposed to each other. 
     Preferably, the wet and dry suction openings are horizontally juxtaposed to each other. Further, at least a portion of one of the wet suction conduit and the dry suction conduit is made of a translucent material so that the working air flow therethrough is visible to a user. Preferably, at least a portion of both of the wet suction conduit and the dry suction conduit are made of a translucent material so that the working air flow therethrough are visible to a user. 
     In a preferred embodiment, the nozzle assembly further comprises a squeegee disposed in the wet suction opening. 
     In a further preferred embodiment, the nozzle assembly is removably mounted to the base. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a perspective view of a bare floor cleaner having a base assembly and a handle assembly according to the invention. 
         FIG. 2A  is perspective view of the base assembly of the bare floor cleaner in  FIG. 1 , wherein a latch is in a locked position to lock a nozzle assembly to the housing of the base assembly. 
         FIG. 2B  is a perspective view of the base assembly in  FIG. 2A , wherein the latch is in an unlocked position to facilitate removal of the nozzle assembly from the housing. 
         FIG. 2C  is an exploded view of the base assembly in  FIG. 2A . 
         FIG. 3A  is a perspective view of the base assembly in  FIG. 2A  with the nozzle assembly and a cover removed. 
         FIG. 3B  is a perspective view of the base assembly in  FIG. 3A  with a diverter housing and hose also removed. 
         FIG. 3C  is a perspective view of the base assembly in  FIG. 2A  and showing the interaction between a cam assembly and a diverter valve. 
         FIG. 3D  is a schematic sectional view taken along line  3 D- 3 D of  FIG. 2A . 
         FIG. 4  is a sectional view of the base assembly taken along line  4 - 4  of  FIG. 2C . 
         FIG. 5A  is a perspective view of a primary cam of the cam assembly in  FIG. 3C  and showing an agitator cam member on one side of the primary cam. 
         FIG. 5B  is a perspective view of the primary cam in  FIG. 5A  and showing a diverter cam member on the other side of the primary cam. 
         FIG. 5C  is a perspective view of the cam assembly of  FIG. 3C  and an actuator for moving the cam assembly. 
         FIGS. 6A-6C  are schematic sectional views of the base assembly in  FIG. 2A  and showing three positions of the primary cam. 
         FIG. 7A  is an exploded view of the handle assembly in  FIG. 1 ; 
         FIG. 7B  is a sectional view of the handle assembly in  FIG. 1 . 
         FIG. 8  is an exploded view of a recovery tank assembly and a filter assembly from the handle assembly in  FIG. 7A . 
         FIG. 9  is an exploded view of a cleaning solution supply tank from the handle assembly in  FIG. 7A . 
         FIG. 10A  is an exploded view of a recovery tank latch assembly from the handle assembly in  FIG. 7A . 
         FIGS. 10B and 10C  are sectional views of the recovery tank assembly and the recovery tank latch assembly from  FIG. 10A  and showing the recovery tank latch assembly in a down position ( FIG. 10B ) and an up position ( FIG. 10C ). 
         FIG. 11A  is perspective view of an alternative base assembly, wherein a latch is in a locked position to lock a nozzle assembly to a housing of the base assembly. 
         FIG. 11B  is a perspective view of the base assembly in  FIG. 11A , wherein the latch is in an unlocked position to facilitate removal of the nozzle assembly from the housing. 
         FIG. 12A  is a sectional view taken along line  12 A- 12 A of  FIG. 11A . 
         FIG. 12B  is a sectional view taken along line  12 B- 12 B of  FIG. 11B . 
         FIG. 13  is a sectional view taken along line  13 - 13  of  FIG. 11A . 
         FIG. 14  is a partial sectional view taken along line  14 - 14  of  FIG. 11A . 
         FIG. 15  is an exploded view of an alternative recovery tank latch assembly. 
         FIG. 16  is a sectional view of the recovery tank latch assembly in  FIG. 15  and a recovery tank. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The invention relates to a bare floor cleaner that is capable of wet pickup from a first nozzle opening with the aid of a squeegee and dry pickup from a second nozzle opening. The bare floor cleaner is equipped with an agitator for wet scrubbing. The invention performs all functions without adding any accessories. 
     Referring now to the figures, and  FIG. 1  in particular, a bare floor cleaner  10  according to the invention for cleaning hard floor surfaces, such as tile, linoleum, and wood, comprises a base assembly  12  and a handle assembly  14  pivotally mounted to the base assembly  12 . The handle assembly  14  houses a recovery tank assembly  162  and a cleaning solution supply tank  224  and is movable between an upright storage position and a reclined working position in which the handle assembly  14  is oriented at an angle less than 90-degrees relative to the surface to be cleaned. When the handle assembly  14  is in the working position, a user can grasp a handle grip  158  to manipulate the bare floor cleaner  10  over the surface to be cleaned. A carrying handle  252  is disposed on the handle assembly  14  for transportation of the bare floor cleaner  10  between uses. A conventional cord wrap  15  is also located on the handle assembly  14  for storage of an electrical cord (not shown) when the bare floor cleaner  10  is not in use. 
     Referring now to  FIGS. 2A-2C , the base assembly  12  comprises a housing  16  having an upper cover  18  and a T-shaped base platform  20 . The upper cover  18  extends from approximately the middle to the rear of the housing  16  and pivotally mounts a latch  24  for securing a dual path nozzle assembly  36  to the housing  16 . The base platform  20  includes an elongated forward portion  21  and a relatively narrow rear portion  22  and comprises a plurality of upstanding bosses  23  for mounting interior components thereto. In addition to the nozzle assembly  36 , the base assembly  12  supports a diverter housing  60  with a diverter valve  64  to switch between the dual paths of the nozzle assembly  36 , an agitator assembly  90 , a control element in the form of a cam assembly  110  in operative communication with the diverter valve  64  and with the agitator assembly  90 , and a dispenser  138  for applying cleaning fluid to the surface to be cleaned. 
     A first pair of wheels  30  is mounted for rotation on axles  31  on opposite sides of the rear portion  22 , and a second pair of smaller wheels  32  ( FIG. 3D ) is rotatably mounted to the forward portion  21 . The wheels  30  and  32  at least partially support the base assembly  12  on the surface to be cleaned and facilitate facile movement of the bare floor cleaner  10  along the surface to be cleaned. The base platform  20  further comprises circular pivot members  34  that are disposed adjacent the first pair of wheels  30  and operably communicate with the handle assembly  14  for pivotally mounting the handle assembly  14  to the base assembly  12 . 
     With continued reference to  FIGS. 2A-2C  and  3 D, the dual paths of the nozzle assembly  36  are formed by a bottom wall  38 , a middle wall  40 , and a top wall  42 . The middle and top walls  40  and  42  are preferably composed of a translucent material. A wet suction path  44  is formed between the bottom wall  38  and the middle wall  40  and has a first or wet nozzle opening  46  that extends transversely along the housing  16  adjacent the surface to be cleaned. The width of the wet suction path  44  is defined by spaced wet nozzle side walls  45  that are integral with the bottom wall  38 . The wet suction path  44  tapers from the elongated first nozzle opening  46  to approximately the width of the diverter housing  60 . A horizontal squeegee  48  is disposed in the center of the first nozzle opening  46  to assist in collecting fluid for suction into the wet suction path  44  and to help support the base assembly  12  on the surface to be cleaned. The squeegee  48  is fixed to the side walls  45  and can optionally comprise nubs on the ends thereof. Because the squeegee  48  is centrally positioned, fluid and dirt can enter the first nozzle opening  46  in a space between the squeegee  46  and middle wall  40  when the bare floor cleaner  10  moves forward or a space between the squeegee  48  and the bottom wall  38  when the bare floor cleaner  10  moves backwards. As a result, the bare floor cleaner  10  can perform wet pickup during both forward and rearward motion. Additionally, the first nozzle opening  46  and the wet suction path  44  are sufficiently narrow to concentrate suction forces for efficient pickup of fluid. 
     A dry suction path  54  overlaps the wet suction path  44  and is formed between the middle wall  40  and the top wall  42 . The dry suction path  54  is in fluid communication with a second or dry nozzle opening  56  that extends transversely along the base assembly  12  parallel to and in front of the first nozzle opening  46 . The width of dry suction path  54  is defined by spaced dry nozzle side walls  55  that are integral with the middle wall  40 . As with the wet suction path  44 , the dry suction path  54  tapers from the second nozzle opening  56  to approximately the width of the diverter housing  60 . As best seen in  FIGS. 2A and 2B , the dry suction path  54  tapers more rapidly than the wet suction path  44 . Consequently, a significant portion of the wet suction path  44  is visible even though the dry suction path  54  overlaps the wet suction path  44 . During operation, a user can see through the translucent top and middle walls  42  and  40  to observe both the dry suction path  54  and the wet suction path  44 . As a result, the user can determine whether any dirt, debris, and the like is flowing or is trapped in the suction paths  44  and  54 . The second nozzle opening  56  and the dry suction path  54  are appropriately sized to accomplish dry pickup and, therefore, are larger relative to the first nozzle opening  46  and the wet suction path  44  when viewed in cross-section, as in  FIG. 3D . Furthermore, the top wall  42  is spaced from the surface to be cleaned to provide clearance for large particles of dirt and debris. Because of this configuration, the bare floor cleaner  10  can capture the large particles of dirt and debris through the second nozzle opening  56 . The nozzle assembly  36  further comprises a resilient bumper  57  that extends forward from the bottom wall  38  and wraps around the bottom edge of the top wall  42 . Preferably, the bumper  57  includes spaced downwardly extending projections  59  that define tapered openings therebetween to concentrate suction forces to facilitate effective dry pickup. 
     The nozzle assembly  36  further includes a pair of horizontal posts  37  ( FIG. 2C ) that extend in opposite directions from the wet nozzle and dry nozzle side walls  45  and  55  and are in operative communication with the latch  24 , which selectively secures the nozzle assembly  36  to the housing  16 . The bottom, middle, and top walls  38 ,  40 , and  42  that together form the nozzle assembly  36  can be removed from the base assembly  12  as a single unit. 
     The latch  24  is a substantially planar member pivotally connected to the cover  18  of the housing  16 . The latch  24  comprises a curved handle grip  86  and downwardly extending hooks  84  adapted to engage the posts  37  on the nozzle assembly  36  to retain the latch  24  in a locked position, as shown in  FIG. 2A . A latch pivot (not shown) includes a detent mechanism for retaining the latch  24  in an unlocked position, as shown in  FIG. 2B , wherein the latch  24  is pivoted away from the cover  18 . 
     With continued reference to  FIGS. 2A-2C , to mount the nozzle assembly  36  to the base assembly  12 , the user grasps the grip  86  and lifts the latch  24  to pivot it to the upward unlocked position. The detent mechanism retains the latch  24  in the unlocked position while the nozzle assembly  36  is attached. After the nozzle assembly  36  is properly situated on the base assembly  12 , the user grasps the handle grip  86  and pushes the latch  24  down towards the cover  18  to a locked position, as shown in  FIG. 2A , wherein the hooks  84  engage the posts  37  to secure the nozzle assembly  36  to the base assembly  12 , and the latch  24  maintains its position due to friction. To remove the nozzle assembly  36  for cleaning or other purposes, the user grasps the handle grip  86  and pivots the latch  24  from the locked position to the unlocked position, thereby spacing the hooks  84  from the posts  37 . The nozzle assembly  36  is then simply pulled from the base assembly  12 . 
     Referring now to  FIGS. 2B ,  2 C, and  3 D, the nozzle assembly  36  abuts the diverter housing  60 , which comprises an upper wall  78  and a lower wall  82  joined by side walls  81 . The diverter housing  60  further comprises a bifurcated first opening  63  in fluid communication with the nozzle assembly  36  and a second opening  65  in fluid communication with a flexible hose  61  that leads to the handle assembly  14 . A seal  67  around the first opening  63  seals the connection between nozzle assembly  36  and the diverter housing  60 . The upper wall  78  and the lower wall  82  that abut the top wall  42  and the bottom wall  38 , respectively, of the nozzle assembly  36 . Further, the diverter housing  60  forms a central vane  62  that abuts the middle wall  40  of the nozzle assembly  36  and includes a lower depression  76  and an upper depression  80 . The vane  62  separates the wet and dry suction paths  44  and  54  within the diverter housing  60  until they converge into a single suction path  58  near the second opening  65 . The single suction path  58  extends from the diverter housing  60  and through the flexible hose  61  to the handle assembly  14 . 
     With additional reference to  FIG. 3C , the diverter valve  64  is disposed in the single suction path  58  adjacent the vane  62  to selectively prevent communication between one of the wet and dry suction paths  44  and  54  and the single suction path  58 . The diverter valve  64  comprises a first elongated door  66  and a second elongated door  68  that join at a keyed hub  71  situated on a keyed shaft (not shown). The keyed shaft and the diverter valve  64  can rotate to alternate between a wet mode and a dry mode. In addition to the first and second doors  66  and  68 , the diverter valve  64  comprises a control lever  73  with first and second levers  72  and  74  mounted on one side of the keyed shaft and external to the diverter housing  60 . A biasing arm  75  is mounted to the other side of the keyed shaft and external to the diverter housing  60 . A spring  77  connected between the biasing arm  75  and a projection  79  that extends from the side of the diverter housing  60 . The biasing arm  75  is coincident with the centerline of the diverter valve, i.e. the biasing arm  75  lies in a plane that bisects the acute angle between the first and second doors  66  and  68 . As a result, the spring  77  acts as an over-center biasing member for the diverter valve  64 , as will be discussed further hereinafter. 
     When the diverter valve  64  is in the dry mode, as shown in phantom in  FIG. 3D , the first door  66  resides in the upper depression  80  in the central vane  62 , and the second door  68  contacts the lower wall  82  of the diverter housing  60  to prevent fluid communication between the single suction path  58  and the wet suction path  44 . In this mode, suction from the single suction path  58  is diverted to the dry suction path  54  for pickup from the second nozzle opening  56 . Rotation of the keyed shaft and the diverter valve  64  to the dry mode, as shown in  FIGS. 3C and 3D , moves the second door  68  so that it rests in the lower depression  76  in the central vane  62 , and the first door  66  contacts the upper wall  78  of the diverter housing  60  to prevent communication between the single suction path  58  and the dry suction path  54 . In this mode, suction from the single suction path  58  is diverted to the wet suction path  44  for pickup from the first nozzle opening  46 . Rotation of the keyed shaft is controlled by the control lever  73 , as will be discussed in detail hereinafter. As the control lever  73  approaches a position halfway between the wet and dry modes, the over-center spring  77  biases the biasing arm  75  and, thus, the diverter valve  64  to either the wet or dry mode, depending on the rotation direction. The spring  77 , combined with suction forces, holds the diverter valve  64  in place in the wet or dry mode. 
     In addition to the nozzle assembly  36 , the base assembly  12  supports an agitator assembly  90 , best seen in FIGS.  2 C and  3 A- 3 C. The agitator assembly  90  comprises an agitator platform  92  that is pivotally mounted to the housing  12 . The agitator platform  92  is situated on a rod  88  ( FIG. 3C ) beneath the diverter housing  60  and comprises a rearward portion  93  and an elongated forward portion  94 . The forward portion  94  includes a central aperture  95  and a generally semi-cylindrical, downwardly facing agitator cover  96  that forms an agitator chamber  98 . A pair of vertical stops  99  extends upwardly along a portion the agitator cover  96 . The platform  92  carries an agitator  100 , preferably a rotatable horizontal axis brush, in the agitator chamber  98 . A motor  102  positioned on the platform  92  adjacent the agitator cover  96  drives the agitator  100 . The motor  102  and the agitator  100  are coupled by means of a conventional belt  104  disposed between a motor drive shaft  103  and an agitator pulley  101 . 
     The rearward portion  93  of the agitator platform  92  terminates at two spaced arms  97  with axial openings  91  that each receives an upstanding boss  23  on the base platform  20 . A spring  89  disposed around each boss  23  biases the rearward portion  93  of the agitator platform  92  away from the base platform  20  to effectively pivot the agitator platform  92  about the rod  88 . As a result, the forward portion  94  is displaced towards the surface to be cleaned to place the agitator  100  in a down position, wherein the agitator  100  contacts the surface to be cleaned. The agitator  100  can be moved to an up position, wherein the agitator  100  is spaced from the surface to be cleaned, by application of downward force on the arms  97  and against the bias of the springs  89  to push the arms  97  towards the base platform  20 . In this case, the agitator platform  92  effectively pivots about the rod  88  to displace the forward portion  94  and, thus, the agitator  100  away from the surface to be cleaned. The vertical stops  99  limit the movement of the agitator platform  92 . To prevent excessive upward displacement of the agitator platform  92 , the vertical stops  99  abut the bottom wall  38  of the nozzle assembly  36 . Movement of the agitator  100  between the down and up positions will be discussed further hereinafter. 
     Referring now to  FIG. 4 , the agitator  100  can be removed from the agitator chamber  98  for replacement, repair, cleaning, or other purposes. A first keyed seat  105  within the agitator  100  selectively interlocks a drive gear  106  coupled to the pulley  101  rotatably mounted to the agitator cover  96 . The other end of the agitator  100  includes a second keyed seat  107  that selectively interlocks a gear  108  that is slidably and rotatably mounted to the agitator cover  96 . A spring  109  disposed between the gear  108  and the agitator cover  96  biases the gear  108  into the second keyed seat  107  and the first keyed seat  105  into the drive gear  106  to thereby retain the agitator  100  in the agitator chamber  98 . 
     Axial force applied to the agitator  100  and against the bias of the spring  109  displaces the agitator  100  in the direction of the spring  109  to thereby compress the spring  109  and laterally displace the gear  108 . Consequently, on the other end of the agitator  100 , the first keyed seat  105  disengages the drive gear  106  such that the agitator  100  can pivot about the gear  108  for removal from the agitator chamber  98 . To mount the agitator  100  within the agitator chamber  98 , the above process is conducted in reverse order. Consequently, the agitator  100  can be removed and replaced or interchanged with a different type of agitator  100  if desired. 
     Referring to  FIGS. 2C ,  3 A- 3 C,  5 A- 5 C, the cam assembly  110  simultaneously controls movement of the agitator  100  between the up and down positions and rotation of the diverter valve  64  between the wet and dry modes. The cam assembly  110  comprises a generally circular primary cam  112  and a secondary cam  113 , each having a keyed center aperture  114  that receives a keyed shaft  116 . The cams  112  and  113  are mounted to the base platform  20  with semicircular clamps  117  and can rotate relative to the base platform  20  and the clamps  117 . The primary cam  112  comprises spaced circumferential grooves  120  that receive a pull-pull cable  130  and peripheral apertures  122  that house cable stops  131 A for mounting the ends of the cable  130  to the primary cam  112 . 
     Both of the cams  112  and  113  comprise an oblong agitator cam member  118  in operable communication with the agitator assembly  90 . In particular, the agitator cam members  118  abut the arms  97  of the rearward portion  93  of the agitator platform  92 , as best viewed in  FIG. 3B . As illustrated in  FIG. 5A , the agitator cam member  118  includes spaced first and second short edges  123  and  124  and spaced first and second long edges  125  and  126  that are substantially perpendicular to the short edges  123  and  124 . The first and second short edges  123  and  124  are joined to the first long edge  125  by rounded corners  127 . 
     When the first long edge  125  is substantially parallel to the arms  97  of the agitator platform  92 , as shown in  FIGS. 3A ,  3 B, and  6 B, the springs  89  surrounding the bosses  23  force the arms  97  upward to contact the first long edges  125  and thereby effectively pivot the agitator assembly  90  so that the agitator  100  is in the down position. Conversely, when either of the first and second short edges  123  and  124  is substantially parallel to the arms  97 , as viewed in  FIGS. 6A and 6C , the agitator cam members  118  apply a downward force to the arms  97  such that the agitator cam members  118  move the agitator platform  92  against the bias of the springs  89 . As a result, the agitator platform  92  effectively pivots about the rod  88  to move the agitator  100  to the up position. The rounded corners  127  between the first long edge  125  and the first and second short edges  123  and  124  facilitate smooth transition of the agitator  100  between the down and up positions during rotation of the cams  112  and  113 . Because the agitator  100  and agitator motor  102  are both mounted to the agitator platform  92 , they are raised and lowered together, which simplifies the belt  104  connection between the two components  100  and  104 . 
     Referring now to  FIGS. 3C and 5B , the cam assembly  110  further comprises a diverter cam member  260  for rotating the diverter valve  64  between the wet and dry modes. The diverter cam member  260  is disposed on the primary cam  112  on the side opposite the agitator cam member  118 . The diverter cam member  262  comprises an arcuate lobe  262  that extends through an angle slightly greater than 90-degrees and a boss  264  that operatively communicates with the control lever  73  of the diverter valve  64 . As the primary cam  112  rotates, the boss  264  interacts with the control lever  73  to rotate the diverter valve  64  between the wet and dry modes. In particular, the rotating boss  264  pushes against either the first or second levers  72  or  74  (depending on the rotation direction) to rotate the control lever  73  and move the diverter valve  64  to the wet or dry mode, respectively. As stated above, the over-center spring  77  biases the diverter valve  64  to either the wet or dry mode, depending on the rotation direction, as the control lever  73  approaches a position halfway between the wet and dry modes. To move the diverter valve  64  from the dry mode shown in  FIG. 6A  to the wet mode shown in  FIG. 6B , the primary cam  112  rotates such that the boss  264  rotates counterclockwise, relative to the orientation of  FIGS. 6A and 6B , to force the first lever  72  to rotate clockwise, relative to the orientation of  FIGS. 6A and 6B . As a result, the diverter valve  64  moves to the wet mode with the first door  66  blocking airflow through the dry suction path  54 . Conversely, to move the diverter valve from the wet mode shown in  FIG. 6B  to the dry mode shown in  FIG. 6A , the primary cam  112  rotates such that the boss  264  rotates clockwise to force the second lever  74  to rotate counterclockwise. As a result, the diverter valve  64  rotates to a position where the second door  68  blocks airflow through the wet suction path  54 . When the diverter valve  64  is in the wet mode, the second lever  74  abuts the arcuate lobe  262 , which prevents inadvertent counterclockwise movement, relative to the orientation shown in  FIGS. 6A and 6B , of the control lever  73 . 
     Referring particularly to  FIG. 5C , rotation of the cams  112  and  113  is accomplished with the pull-pull cable  130 . The pull-pull cable  130  comprises a first cable  132  and a second cable  136 , both of which extend from an actuator  134  ( FIG. 1 ) in the handle assembly  14  to the primary cam  112 . Similar to the primary cam  112 , the actuator  134  comprises spaced circumferential grooves  133 , wherein each of the grooves  133  receives one of the cables  132 ,  136 . Cable stops  131 B secure the ends of the cables  132 ,  136  to the actuator  134 . Adjacent the actuator  134  is a handle cable guide  310 , which comprises a pair of secondary channels  314 ,  316 , that merge into a primary channel  312 . The first cable  132  extends from its cable stop  131 B, rides in one of the grooves  133  of the actuator  134 , and enters the handle cable guide  310  at the secondary channel  314 . The second cable  136  extends from its cable stop  131 B, rides in the other circumferential groove  133  in a direction opposite of the first cable  132 , and enters the handle cable guide  310  at the other secondary channel  316 . When the secondary channels  314 ,  316  merge, the first and second cables  132 ,  136  both reside in the primary channel  312  until they leave the handle cable guide  310 . 
     The first and second cables  300  extend from the handle cable guide  310  to the base assembly, where they enter a base cable guide  300  located adjacent the cam assembly  110 . The base cable guide  300  comprises a primary channel  302  that diverges into secondary channels  304 ,  306 . Both the first and second cables  132 ,  136  enter the base cable guide  300  at the primary channel  302  and then split to reside in their respective secondary channels  304 ,  306 . The first cable  132  leaves the base cable guide  300  through the secondary channel  304  and extends towards the primary cam  112 . The first cable  132  rides in one of the grooves  120  along the top of the primary cam  112  and terminates at its cable stop  131 A. The second cable  136  leaves the base cable guide  300  through the other secondary channel  306  and extends towards the primary cam  112 . The second cable  136  enters the other groove  120  of the primary cam  112  from the bottom of the primary cam  112  and terminates at its cable stop  131 A. 
     Because the actuator  134  is coupled with the cam assembly  110  by the cable  130  in the manner described above, rotation of the actuator  134  in one direction rotates the primary cam  112  in a first direction, and rotation of the actuator  134  in an opposite direction rotates the primary cam  112  in a second direction opposite to the first direction. For example, when the actuator  134  rotates clockwise (relative to the orientation of  FIG. 5C ), the actuator  134  pulls the first cable  132 , which thereby rotates the cam  112  clockwise (relative to the orientation of  FIG. 5C ). Conversely, when the actuator  134  rotates counterclockwise, the actuator  134  pulls the second cable  136 , which thereby rotates the cam  112  counterclockwise. Because the cams  112  and  113  are joined by the keyed shaft  116 , the secondary cam  113  rotates with the primary cam  112 . 
     Rotation of the primary cam  112  by means of the pull-pull cable  130  simultaneously controls the positions of the agitator  100  and the diverter valve  64 . The single actuator  134  rotates the primary cam  112  and, thus, the secondary cam  113  between at least three positions: a first position ( FIG. 6A ) wherein the agitator  100  is in the up position and the diverter valve  64  is in the dry mode, a second position ( FIG. 6B ) wherein the agitator  100  is in the down position and the diverter valve  64  is in the wet mode, and a third position ( FIG. 6C ) wherein the agitator  100  is in the up position and the diverter valve  64  is in the wet mode. The three positions of the actuator  134  and the primary cam  112  correspond to the following three cleaning modes: dry pickup, wet scrubbing, and wet pickup. In the first position, the first short edge  123  of the agitator cam member  118  abuts the agitator platform  92 , and the boss  264  of the diverter cam member  260  is positioned between the first and second levers  72  and  74 . When the primary cam  112  moves to the second position from the first position, the first long edge  125  of the agitator cam member  118  abuts the agitator platform  92 , and the boss  264  abuts the first lever  72  of the control lever  73  to force the diverter valve  64  to rotate to the wet mode. The diverter valve  64  remains in the wet mode when the primary cam  112  rotates to the third position, and the agitator cam member  118  rotates such that the second short edge  125  abuts the agitator platform  92  to move the agitator  100  to the up position. When the primary cam  112  rotates from the second position to the first position, the agitator cam member  118  rotates such that the first long edge  125  abuts the agitator platform  92 , and the boss  264  abuts the second lever  74  of the control lever  73  to force the diverter valve  64  to rotate to the dry mode. Because the primary cam  112  can rotate in two directions, it can rotate between the positions in any reasonable order. For example, the primary cam can rotate from the first to the second to the third positions or from the third to the second to the first positions. Further, the primary cam  112  in the second position can rotate to either the first position or to the third position. 
     As stated previously, the base assembly  12  supports the cleaning solution dispenser  138 , which is best seen in  FIGS. 2C ,  3 A, and  3 B, that is part of a cleaning solution dispensing system. The dispenser  138  is preferably disposed between the nozzle assembly  36  and the agitator assembly  90  and, in particular, between the agitator cover  96  and the nozzle assembly bottom wall  38 . The dispenser  138  extends transversely along the width of the base assembly  12 , and includes a plurality of downwardly facing apertures of uniform or varying size. The dispenser  138  distributes and delivers cleaning solution to the surface to be cleaned through the apertures. The dispenser  138  further includes upstanding L-shaped solution tubes  140  that receive cleaning solution from a distributor  141  mounted to the base platform  20 . The distributor  141  is surrounded by the agitator platform  92  and is received with the central aperture  95  of the agitator platform  92  so that the distributor  141  does not interfere with vertical movement of the agitator assembly  90 . The distributor  141  and the solution tubes  140  are fluidly connected by a pair of solution conduits  251 . The remainder of the cleaning solution dispensing system will be described in detail hereinafter. 
     Referring now to  FIGS. 7A and 7B , the handle assembly  14  comprises a lower handle  142  and an upper handle  144 . The lower handle  142  comprises a pair of generally vertical spaced legs  146  joined at the upper ends thereof by a horizontal region  148  and at the rear edges by a rear handle housing  228 . Trunnion assemblies  150  with pivot pins  151  are disposed at the lower ends of each spaced leg  146  and mate with the pivot members  34  of the base assembly  12  to form a pivot connection in a conventional fashion. The upper handle  144  comprises a forward section  152  and a rearward section  154  that mate to form a chamber  156  therebetween. The assembled upper handle  144  has a slightly curved profile and terminates at the handle grip  158  at the upper end thereof. The upper handle  144  is mounted to the lower handle  142  at the lower end thereof. 
     The handle assembly  14  supports several components of a recovery system for removing and storing dry and wet dirt and debris and soiled cleaning solution from the surface to be cleaned. The recovery system comprises a motor and fan assembly  160 , the recovery tank assembly  162 , and a suction conduit  163 . The motor and fan assembly  160 , which creates suction forces to remove wet and dry debris from the surface to be cleaned, is disposed within a motor and fan assembly housing  159  mounted to the lower handle  142  adjacent the horizontal region  148 . The motor and fan assembly housing  159  comprises an inlet (not shown) and an exhaust outlet (not shown) for the motor and fan assembly  160  at a lower end at an upper end thereof, respectively. The motor and fan assembly  160  draws air through the inlet and exhausts the air through the outlet. Power to the motor and fan assembly  160  is controlled by a user-operated switch  161  preferably located near the cam assembly actuator  134  on the handle assembly  14 . Optionally, power to the agitator motor  102  can be controlled with the same switch  161 . 
     With additional reference to  FIG. 8 , the recovery tank assembly  162  comprises a recovery tank  168  having a generally curved front wall  172 , a generally flat rear wall  174  joined to rear edges of the front wall  172 , and a bottom wall  176  joined to bottom edges of the front wall  172  and the rear wall  174 . A recovery chamber  178  defined within the recovery tank  168  receives and stores dry and wet dirt and debris and soiled cleaning solution. A lid  180  with a cylindrical center aperture  182  is positioned above the recovery tank  168  to enclose the recovery chamber  178 . A float cage  184  for holding a float  186  is mounted to the lid  180  in axial alignment with the cylindrical center aperture  182 . When the level of liquid in the recovery chamber  178  rises to the level of the float cage  184 , the float  186  is forced upward and seals the cylindrical center aperture  182  such that air cannot be drawn from the motor and fan assembly  160  through the recovery chamber  178 . The lid  180  further comprises a handle  188  that extends slightly forward of front wall  172  of the recovery tank  168 . The lid  180  and the recovery tank front wall  172  each have a depressed region  190  that mate to form a cavity behind the handle  188  to accommodate at least a portion of a user&#39;s hand. 
     A filter assembly  170  is positioned between the recovery tank lid  180  and the motor and fan assembly  160  and comprises an upper housing  194  and a lower housing  195 . The upper housing  194  has center and rear channels  196  and  198 , which are best viewed in  FIG. 8 . The housing  194  is joined to the lid  180  with a seal  200  therebetween, and the center channel  196  is aligned with the cylindrical center aperture  182  of the lid  180  and the inlet to the motor and fan assembly  160 . A filter  202 , preferably a replaceable filter, is located in the center channel  196  to remove particles that are drawn with the working air through the cylindrical center aperture  182  to thereby prevent the remaining particles from entering into the motor and fan assembly  160 . 
     The recovery tank assembly  162  is situated on a recovery tank latch assembly  204 , shown in detail in  FIGS. 10A-10C , which is mounted to the lower handle  142  and comprises a lower platform  206  and an upper platform  208  with a rotatable cam latch  210  and a cam follower  211  therebetween. The lower platform  206  comprises a circular depression  207  that receives the cam latch  210 . The cam latch  210  is a generally tubular structure  218  with a radially extending latch handle  213  that projects forward of the handle assembly  14  and an axial stub  215  that is rotatably received in a central opening  209  in the lower platform  206 . The cam latch  210  further comprises circumferential ramps  217  on the inner surfaces of the tubular structure  218 . The cam follower  211  comprises a cylindrical lower portion  205  sized to be axially received within the tubular structure  218  and a planar upper portion  216 . The lower portion  205  includes a series of external threads  219  in operative communication with the cam latch ramps  217 . Further, the upper portion  216  comprises a plurality of upstanding pins  220  on its upper surface that are aligned with a plurality of holes  221  through the upper platform  208 . The upper platform  208  further comprises an integral shield  222  that hides a portion of the recovery tank latch assembly  204  for aesthetic purposes. 
     While lower platform  206  and the upper platform  208  are stationary with respect to the handle assembly  14 , the cam latch  210  can be rotated by moving the latch handle  213  in an arcuate path. When the cam latch  210  rotates, the cam follower threads  219  ride along the cam latch ramps  217 , as in a conventional mechanical thread. Consequently, rotation of the cam latch  210  vertically displaces the cam follower  211  within the tubular structure  218  to thereby move the pins  220  between a down position, wherein the planar upper portion  216  is spaced from the upper platform  208  and the pins  220  project above the upper platform  208  a first distance, as shown in  FIG. 10B , and an up position, wherein the planar upper portion  216  abuts the upper platform  208  and the pins  220  project above the upper platform  208  a second distance greater than the first distance, as illustrated in  FIG. 10C . 
     To mount the recovery tank assembly  162  to the handle assembly  14 , a user situates the recovery tank latch assembly  204  so that the pins  220  are in the down position and places the recovery tank assembly  162  on the upper platform  208 . Next, the user rotates the latch handle  213  through an arc to thereby rotate the cam latch  210  and raise the cam follower  211 . As the cam follower  211  rises, the pins  220  move to the up position, contact the bottom wall  176  of the recovery tank  168 , and push the recovery tank assembly  162  upwards to effectively seal the lid  180  with the filter assembly  170 . 
     To remove the recovery tank assembly  162 , a user arcuately slides the latch handle in an opposite direction to thereby lower the cam follower  211  and move the pins  220  to the down position. The recovery tank assembly  162  moves downward with the cam follower  211  and is, therefore, no longer sealed with the filter assembly  170 . The user can thereafter pull the recovery tank assembly  162  from the handle assembly  14  by grasping the recovery tank  168  and the handle  188  on the recovery tank lid  180 . When the recovery tank assembly  162  is removed from the bare floor cleaner  10 , the recovery chamber  178  can be emptied, and the filter assembly  170  can be removed from the bare floor cleaner  10  for cleaning and replacement of the filter  202 , if necessary. 
     Referring to  FIGS. 7A and 7B , the suction conduit  163  couples with the flexible hose  61  adjacent the base assembly  12  and extends up the handle assembly  14 , specifically between the spaced legs  146  of the lower handle  142 , and curves forward approximately 180-degrees to terminate in the rear channel  198  of the filter assembly  170  for connection to the recovery tank  168 . At this point, the single suction path  58 , which extends from within the diverter housing  60 , through the flexible hose  61 , and through the suction conduit  163 , fluidly communicates with the recovery chamber  178  and, therefore, the filter assembly  170  and the motor and fan assembly  160 . Recovered soiled liquid and air in the suction conduit  163  turns 180-degrees and impinges on baffle surfaces while entering the recovery chamber  178 . As a result, the airflow slows, the liquid and debris separates from the air and drops down into the recovery tank  168  while the recovered air continues to travel through the filter assembly  170  and the motor and fan assembly  160 . A panel  165  mounted between the spaced legs  146  hides the suction conduit  163  from view when the recovery tank assembly  162  is removed form the handle assembly  14 . 
     The motor and fan assembly  160  creates an airflow that is drawn through a working air path defined by either the wet or dry suction path  44  or  54  of the nozzle assembly  36 , the single suction path  58  through the diverter housing  60 , the hose  61 , and the suction conduit  163 , the recovery chamber  178 , the central channel  196  of the filter assembly  170 , and the inlet of the motor and fan assembly  160 . The recovery system is a clean air system wherein the debris is removed from the working air path prior to reaching the motor and fan assembly  160 . 
     Referring now to  FIGS. 7A ,  7 B, and  9 , the handle assembly  12  also supports several components of the cleaning solution dispensing system, which stores and preferably heats cleaning solution and distributes the cleaning solution to the surface to be cleaned. The dispensing system comprises the cleaning solution supply tank  224 , a supply tank feed valve  242  operated by a trigger  246  disposed in the handle grip  158 , and an in-line heating element  226  that optionally heats the cleaning solution before it reaches the distributor  141  and the dispenser  138  described hereinabove. 
     The supply tank  224  is seated on the rear handle housing  228  of the lower handle  142 . The rear handle housing  228  is preferably located behind the recovery tank assembly  162  such that the supply tank  224 , when seated on the rear handle housing  228 , is positioned substantially adjacent the motor and fan assembly  160 . The supply tank  224  has a generally triangular shape with an integrally formed handle  230  to facilitate removal and transportation of the supply tank  224 . The supply tank comprises a curved front wall  232  joined to side walls  233 , a substantially flat rear wall  234  with a depression  235  to facilitate mounting the supply tank  224  to the handle assembly  14 , and a bottom wall  236  with a tank feed/fill opening  238 . The supply tank  224  defines a supply chamber  240  for storing cleaning solution, which is supplied through the tank feed/fill opening  238 . The tank feed/fill opening  238  is sized to receive the supply tank feed valve  242 , which is coupled to a vent tube  243  that projects into the supply chamber  240 . Further details of the supply tank  224  and the supply tank feed valve  242  are disclosed in U.S. Pat. No. 6,467,122, which is incorporated herein by reference in its entirety. The supply tank feed valve  242  is operatively coupled with a rod  244  connected to the trigger  246 . The supply tank feed valve  242  is normally biased to a closed position and can be urged to an open position by squeezing the trigger  246  to thereby displace the rod  244  to open the supply tank feed valve  242 . When the supply tank feed valve  242  is in the open position, cleaning solution flows from the supply tank  224  and through the valve  242  under the influence of gravity. The supply tank feed valve  242  is fluidly connected to the in-line heating element  226  by a first supply conduit  248 . 
     The in-line heating element  226  is preferably mounted in the rear handle housing  228  and receives the first supply conduit  248  at an upper end and a second supply conduit  250  at a lower end. A suitable in-line heating element  226  is disclosed in U.S. Pat. No. 6,131,237, which is incorporated herein by reference in its entirety. The cleaning solution is delivered by force of gravity or, alternatively, by a fluid pump to the in-line heating element  226  through the first supply conduit  248 . The in-line heating element  226  heats the cleaning solution as it travels therethrough, and the cleaning solution exits the in-line heating element  226  through the second supply conduit  250 . The second supply conduit  250  can comprise one more individual conduits to deliver heated cleaning solution from the in-line heating element  226  to the distributor  141  in the foot assembly  12 . Power to the in-line heating element  226  is controlled by a user-operated switch  227  preferably located near the cam assembly actuator  134  on the handle assembly  14 . When heated cleaning solution is desired, the user activates the in-line heating element  226  with the switch  227 . Otherwise, the cleaning solution flows through the inactivated in-line heating element  226  without a significant increase in temperature. 
     As best seen in  FIG. 3B , the second supply conduit  250  fluidly communicates the in-line heating element  226  with the distributor  141  and the dispenser  138  in the base assembly  12 . The cleaning solution from the in-line heating element  226  travels under force of gravity to the distributor  141 , which distributes the cleaning solution to the dispenser  138 . After entering the dispenser  138  through the tubes  140 , the cleaning solution flows through the apertures to the surface to be cleaned. Optionally, the bare floor cleaner  10  can further comprise a fluid pump in the handle assembly  14  or the base assembly  12  to pump the cleaning solution from the cleaning solution dispensing system. 
     To operate the bare floor cleaner  10 , the cleaning solution tank  224  is removed from the handle assembly  14 , and cleaning solution is delivered to the supply chamber  240  through the tank feed/fill opening  238 . The filled cleaning solution tank  224  is returned to the bare floor cleaner  10  and seated on the rear handle housing  228 . Next, the handle assembly  14  is pivoted to the reclined working position, and electricity is provided to the motor and fan assembly  160  and the agitator motor  102  through the switch  161  on the handle assembly  14 . The motor and fan assembly  160  draws a vacuum through the nozzle assembly  36 , the diverter housing  60 , the flexible hose  61 , the suction conduit  163 , the recovery tank assembly  162 , and the central channel  196  of the filter assembly  170 . 
     The bare floor cleaner can operated in the three previously described cleaning modes: dry pickup, wet scrubbing, and wet pickup. The cleaning mode is selected by rotating the actuator  134  on the handle assembly  14 . For exemplary purposes, the operation of the dry pickup mode will be described first, followed by the operation of the wet scrubbing mode and, finally, the wet pickup mode. The modes, however, can be operated in any order. The order in which the modes are described and the exemplary descriptions of each mode are not intended to limit the invention in any manner. 
     In the dry pickup mode, the pull-pull cable  130 , which is operatively connected to the actuator  134 , rotates the cams  112  and  113  to the first position to orient the agitator  100  in the up position and the diverter  64  in the dry mode to permit suction through the dry suction path  54  and to prevent suction through the wet suction path  44 . As the bare floor cleaner  10  moves over the surface to be cleaned, loose dirt, dust, debris, and the like located near the second nozzle opening  56  are drawn into the dry suction path  54 . Particles of a relatively large size, such as the size of a piece of popcorn, can enter the second nozzle opening  56  due to the clearance between the top wall  42  of the nozzle assembly  36  and the surface to be cleaned. Dirt and air in the dry suction path  54  are drawn into the diverter housing  60 , past the diverter  64  into the single suction path  58 , through the hose  61  and suction conduit  163 , and through the 180-degree turn into the recovery chamber  178 , where the dirt is separated from the working air and stored therein. The air continues to be drawn through the center cylindrical aperture  182  of the lid  180  and the filter  202  in the center channel  196  of the filter assembly  170 , where any remaining dust and the like is removed from the air. Finally, the clean air enters the inlet of the motor and fan assembly  160  and exits through the exhaust outlet. After the loose dirt, dust, debris, and the like are removed from the surface to be cleaned, the actuator  134  is rotated to operate the bare floor cleaner  10  in the wet scrubbing mode. 
     In the wet scrubbing mode, the pull-pull cable  130  rotates the cams  112  and  113  to the second position such that the agitator  100  is in the down position and the diverter  64  is in the wet mode to permit suction through the wet suction path  44  and to prevent suction through the dry suction path  54 . If the user desired heated cleaning solution, the switch  227  on the handle assembly actuated to activate the in-line heating element  226 . To apply cleaning solution to the surface to be cleaned, the trigger  246  on the handle grip  158  is depressed and thereby moves the rod  244  to open the cleaning solution feed valve  242 . Cleaning solution travels from the supply chamber  240  and through the cleaning solution feed valve  242  and the first supply conduit  248  to the in-line heating element  226 , where the cleaning solution is optionally heated. The cleaning solution leaves the in-line heating element  226  and flows under the force of gravity through the second supply conduit  250  to the distributor  141 , through the solution conduits  251  to the dispenser  138 , and, ultimately, to the surface to be cleaned. As the bare floor cleaner  10  moves forward and backward over the surface to be cleaned, the rotating agitator  100  interacts with the cleaning solution and the dirt, dust, and debris adhered to the surface to be cleaned. Such interaction removes the adhered dirt, dust, and debris, which become suspended in the cleaning solution. 
     Soiled cleaning solution and dirt near the first nozzle opening  46  is scraped by the squeegee  48  and drawn into the wet suction path  44 . When the bare floor cleaner  10  moves forward, the soiled cleaning solution collects between the squeegee  48  and the middle wall  40  of the nozzle assembly  36 , whereas the soiled cleaning solution collects between the squeegee  48  and the bottom wall  38  of the nozzle assembly  36  when the bare floor cleaner  10  moves backward. Optionally, the motor and fan assembly  160  can be inoperative during the wet scrubbing mode so that the soiled cleaning solution is not removed from the surface to be cleaned. 
     When the motor and fan assembly  160  is operative, soiled cleaning solution, dirt, and air in the wet suction path  44  are drawn into the diverter housing  60 , past the diverter  64  into the single suction path  58 , through the hose  61  and suction conduit  163 , and through the 180-degree turn into the recovery chamber  178 , where the soiled cleaning solution and dirt are separated from the working air and stored therein. The air is drawn through the center cylindrical aperture  182  of the lid  180  and the filter  202  in the center channel  196  of the filter assembly  170 , where any remaining dust and the like is removed from the air. Finally, the clean air enters the inlet to the motor and fan assembly  160  and exits through the exhaust outlet. After the wet scrubbing mode is completed, the actuator  134  is rotated to operate the bare floor cleaner  10  in the wet pickup mode. 
     In the wet pickup mode, the pull-pull cable  130  rotates the cams  112  and  113  to the third position such that the agitator  100  is in the up position and the diverter  64  is in the wet mode to permit suction through the wet suction path  44  and to prevent suction through the dry suction path  54 . As the bare floor cleaner  10  moves forward and backward over the surface to be cleaned, soiled cleaning solution and dirt near the first nozzle opening  46  is scraped by the squeegee  48  and drawn into the wet suction path  44 . When the bare floor cleaner  10  moves forward, the soiled cleaning solution collects between the squeegee  48  and the middle wall  40  of the nozzle assembly  36 , whereas the soiled cleaning solution collects between the squeegee  48  and the bottom wall  38  of the nozzle assembly  36  when the bare floor cleaner  10  moves backward. As in the wet scrubbing mode, soiled cleaning solution, dirt, and air in the wet suction path are drawn into the diverter housing  60 , past the diverter  64  into the single suction path  58 , through the hose  61  and the suction conduit  163 , and through the 180-degree turn into the recovery chamber  178 , where the soiled cleaning solution and dirt are separated from the working air and stored therein. The air is then drawn through the center cylindrical aperture  182  of the lid  180  and the filter  202  in the center channel  196  of the filter assembly  170 , where remaining dust and the like is removed from the air. Finally, the clean air enters the inlet to the motor and fan assembly  160  and exits through the exhaust outlet. 
     After the wet pickup mode is completed, the electricity to the motor and fan assembly  160  and the brush motor  102  is turned off via the switch  161 , power to the in-line heating element  226  is turned off via the switch  227  if heated cleaning solution is utilized, and the handle assembly  14  can be pivoted to the upright storage position. Because the bare floor cleaner  10  is efficient at removing soiled solution from the surface, only a short drying time is required before foot traffic is acceptable. 
     Following use of the bare floor cleaner  10 , the recovery tank assembly  162  can be removed as described hereinabove to empty the recovery chamber  178 . Removal of the recovery tank assembly  162 , or the supply tank  224 , can be accomplished while the handle assembly  14  is in either the upright or reclined positions. When the recovery chamber  178  becomes full during use of the bare floor cleaner  10 , the float  186  closes the cylindrical center aperture  182  of the recovery tank lid  180 , thereby ceasing operation of the recovery system. At this point, the recovery tank assembly  162  should be removed to empty the recovery chamber  178 . 
     In addition to the three operation modes described above, the bare floor cleaner  10  can alternatively be configured to operate in a fourth mode, a dry scrubbing mode, wherein the agitator  100  is in the down position and the diverter  64  in the dry mode to permit suction through the dry suction path  54  and to prevent suction through the wet suction path  44 . In this alternative embodiment, the agitator cam members  118  on the primary cam  112  and the secondary cam  113  and the diverter cam member  260  on the primary cam  112  are altered such that the agitator  100  and the diverter  64  can be suitably positioned for the dry scrubbing mode. 
     An alternative base assembly  12 ′ for the bare floor cleaner  10  is illustrated in  FIGS. 11A-14 , where like elements are identified with the same reference numeral bearing a prime (′) symbol. The primary differences between the alternative base assembly  12 ′ and the first embodiment base assembly  12  are the latch  24 ′ for securing the nozzle assembly  36 ′ to the base assembly  12 ′, the agitator assembly  90 ′, and the cam assembly  110 ′. 
     Referring now to  FIGS. 11A ,  11 B,  12 A, and  12 B, the latch  24 ′ is a substantially planar member pivotally connected to the cover  18 ′ of the housing  16 ′. The latch  24 ′ comprises a forwardly extending handle  86 ′, a rearwardly extending projection  270  with a pivot rod  272  extending therethrough, and a downwardly and rearwardly extending finger  274  located beneath the projection  270 . When the latch  24 ′ is in a locked position, as shown in  FIGS. 11A and 12A , the finger  274  abuts an upwardly extending flange  276  on the top wall  42 ′ of the nozzle assembly  36 ′ to push the nozzle assembly  36 ′ against the diverter housing  60 ′ and thereby secure the nozzle assembly  36 ′ to the base assembly  12 ′. The latch  24 ′ is pivotable about the pivot rod  272  to an unlocked position, as shown in  FIGS. 11B and 12B , wherein the finger  274  is spaced from the flange  276  on the top wall  42 ′ of the nozzle assembly  36 ′ so that the nozzle assembly  36 ′ can be removed from the base assembly  12 ′. The latch  24 ′ in the unlocked position remains in that position due to friction until a user applies downward force to the handle  86 ′ to pivot the latch about the pivot rod  272  towards the base assembly  12 ′. 
     To remove the nozzle assembly  36 ′ for cleaning or other purposes, a user grasps the handle  86 ′ pivots the latch  24 ′ about the pivot rod  272  from the generally horizontal, locked position to the generally vertical, unlocked position, thereby spacing the finger  274  from the flange  276 . The user then simply pulls the nozzle assembly  36 ′ from the base assembly  12 ′. To return the nozzle assembly  36 ′, the user places the nozzle assembly  36 ′ on the base assembly  12 ′ so that the flange  276  on the top wall  42 ′ of the nozzle assembly  36 ′ abuts the diverter housing  60 ′ while the latch  24 ′ is in the unlocked position. Next, the user pivots the handle  86 ′ to the locked position, whereby the finger  274  rotates to abut the flange  276  and thereby retain the nozzle assembly  36 ′ on the base assembly  12 ′. 
     Referring now to  FIG. 13 , the agitator assembly  90 ′ comprises a generally flat agitator platform  92 ′ that is mounted to the base assembly  12 ′ through a flange  284  and a central pivot pin  286  and has, at a forward portion  94 ′, a generally semi-cylindrical, downwardly facing agitator cover  96 ′ that forms an agitator chamber  98 ′. The platform  92 ′ carries an agitator  100 ′, preferably a rotatable horizontal axis brush, in the agitator chamber  98 ′. A motor  102 ′ is positioned on the platform  92 ′ adjacent the agitator cover  96 ′ and drives the agitator  100 ′. The motor  102 ′ and the agitator  100 ′ are coupled by means of a conventional belt  104 ′ disposed between a motor drive shaft  103 ′ and an agitator pulley  101 ′. Two spaced upwardly extending tabs  280  are disposed at a rearward portion  93 ′ of the platform  92 ′ and a platform pin  282  extends along the entire width of the platform  92 ′ between the two tabs  280 ′. The platform pin  282 ′ is retained at its center by the cam assembly  110 ′, which is mounted in the base housing  16 ′. 
     The cam assembly  110 ′ comprises a generally circular cam  112 ′ having a keyed center aperture  114 ′ that is mounted on a keyed shaft  116 ′. The cam  112 ′ comprises an irregularly shaped slot  290  that slidingly receives the platform pin  282 . As the keyed shaft  116 ′ and the cam  112 ′ rotate, the platform pin  282  slides along the slot  290 . Due to the irregular shape of the slot  290 , the platform pin  282  moves up and down during rotation of the cam  112 ′, thereby raising and lowering the rearward portion  93 ′ of the platform  92 ′. When rearward portion  93 ′ of the platform  92 ′ moves up and down, the platform  92 ′ pivots about the central pivot pin  286 , thereby lowering and raising, respectively, the forward portion  94 ′ of the platform  92 ′ and, therefore, the agitator  100 ′. When the cam  112 ′ drives the pin  282  upward, the agitator  100 ′ is driven towards the surface to be cleaned. Conversely, the agitator  100 ′ is raised from the surface to be cleaned when the cam  112 ′ drives the pin  282  downward. Because the agitator  100 ′ and agitator motor  102 ′ are both mounted to platform  92 ′, they are raised and lowered together, which simplifies connection of the belt  104 ′ between the agitator  100 ′ and the motor  102 ′. 
     Preferably, the slot  290  is shaped to alternate the agitator  100 ′ between three positions: a first up position, a down position, and a second up position.  FIG. 13  shows the agitator  100 ′ in the first up position, raised from the surface to be cleaned. When the cam  112 ′ rotates counterclockwise, relative to the orientation of the  FIG. 13 , the platform pin  282  slides within the slot  290  to a location labeled  292  (shown in phantom). When the cam  112 ′ rotates to position the platform pin  282  at the location  292 , the platform pin  282  is displaced upward whereby the agitator  100 ′ simultaneously moves to the down position in contact with the surface to be cleaned. Further counterclockwise rotation of the cam  112 ′ moves the platform pin  282  to a location labeled  294  and to move the agitator  100 ′ to the second up position. Here, the platform pin  282  is lowered to a height equal to that of the first up position, and the agitator  100 ′ is thereby raised from the surface to be cleaned. 
     Referring now to  FIG. 14 , the cam assembly  110 ′ further comprises means for rotating the diverter valve  64 ′ between wet and dry modes. The cam  112 ′ comprises, on one side thereof, a diverter cam member  260 ′ that forms two grooves, an upper groove  266  and a lower groove  268 . The lower groove  268  receives the first lever  72 ′ of the control lever  73 ′ of the diverter valve  64 ′, and similarly, the second lever  74 ′ of the control lever  73 ′ is seated in the upper groove  266 . The first and second levers  72 ′,  74 ′ are moveable within the lower and upper grooves  268 ,  266 , respectively. As the keyed shaft  116 ′ and the cam  112 ′ rotate, the levers  72 ′ and  74 ′ are displaced by the diverter cam member  260 ′ to thereby force the diverter valve  64 ′ to pivot about its keyed shaft between the wet and dry modes. 
     Rotation of the cam assembly  110 ′ to simultaneously control the positions of the agitator  100 ′ and the diverter valve  64 ′ is accomplished with a pull-pull cable controlled by an actuator in a manner similar to the first embodiment base assembly  12 . The single actuator rotates the cam  112 ′ between at least three positions: a first position wherein the agitator  100 ′ is in the first up position and the diverter valve  64 ′ is in the dry mode, a second position wherein the agitator  100 ′ is in the down position and the diverter valve  64 ′ is in the wet mode, and a third position wherein the agitator  100 ′ is in the second up position and the diverter valve  64 ′ is in the wet mode. The three positions of the cam  112 ′ correspond to the dry pickup, wet scrubbing, and wet pickup operating modes. 
     An alternative recovery tank latch assembly  204 ′ for the bare floor cleaner  10  is illustrated in  FIGS. 15 and 16 , where like elements are identified with the same reference numeral bearing a prime (′) symbol. The recovery tank latch assembly  204 ′ is mounted to the spaced legs  146 ′ of the lower handle  142 ′ and supports the recovery tank assembly  162 ′. The recovery tank latch assembly  204 ′ comprises a lower platform  206 ′, an upper platform  208 ′, and a slidable latch  210 ′ therebetween. The upper platform  208 ′ has an upper surface  212 , which is generally parallel to the surface to be cleaned when the bare floor cleaner  10 ′ is in the upright storage position, and a lower surface  214 , which is inclined relative to the upper surface  212  such that the upper platform  208 ′ is thicker at the rear than at the front. The slidable latch  210 ′ is generally wedge-shaped and has an upper surface  223  that is inclined to mate with the inclined lower surface  214  of the upper platform  208 ′. The slidable latch  210 ′ further comprises a latch handle  213 ′ and an upwardly extending flange  225 . When situated on the recovery tank latch assembly  204 ′, the recovery tank  168 ′ rests on the upper surface  212  of the upper platform  208 ′ and is retained in place by lugs or recessed features (not shown) on the recovery tank  168 ′ that engage with corresponding features (not shown) on the handle assembly  14 ′. In this position, the lid  180 ′ abuts the filter assembly  170 ′ with the seal  200 ′ therebetween, and the recovery tank  168 ′ is securely retained on the handle assembly  14 ′. 
     To remove the recovery tank assembly  162 ′, a user pulls the slidable latch  210 ′ forward by means of the latch handle  213 ′, as shown in phantom in  FIG. 16 , such that a space  229  is created between the upwardly extending flange  225  and the recovery tank  168 ′. As the user slides the latch  210 ′ forward, the recovery tank  168 ′ falls downward and forward into the space  229  as the lid  180 ′ separates from the filter assembly  170 ′ at the seal  200 ′. Next, the user places a hand in the depressed region  190 ′ behind the handle  188 ′ of the recovery tank assembly  162 ′, grasps the handle  188 ′, and pulls the recovery tank assembly  162 ′, including the tank  168 ′ and the lid  180 ′, forward for removal from the bare floor cleaner  10 ′. To mount the recovery tank assembly  162 ′ to the handle assembly  14 ′, this removal process is generally conducted in a reverse order. 
     The bare floor cleaner  10  can alternatively comprise dual recovery tanks: a wet recovery tank for use when the diverter valve  64  is in the wet mode and a dry recovery tank that for use when the diverter valve  64  is in the dry mode. When the bare floor cleaner  10  comprises dual recovery tanks, the recovery system can include another diverter positioned between both outlets of the wet and dry recovery tanks and the motor and fan assembly  160  to direct the working air path through the desired recovery tank. In another alternate embodiment, the recovery tank  168  is divided into two separate compartments: one compartment to receive wet debris from the first or wet nozzle opening  46  and a second compartment to receive dry debris from the second or dry nozzle opening  56 . In this embodiment, the diverter  64  is located downstream of the recovery tank assembly  162  and upstream of the motor and fan assembly  160  and can be actuated in a similar fashion as in the first embodiment to switch between wet and dry modes. 
     Furthermore, the nozzle assembly  36  can comprise a retractable squeegee  48  that can be manually raised from the surface to be cleaned. The user can manually retract the squeegee, such as when the bare floor cleaner  10  is in the dry pickup mode, to prevent undesirably transferring any residual liquid thereon to the surface to be cleaned. 
     Additionally, the invention has been disclosed with respect to a bare floor cleaner with an agitator in the form of a horizontal axis, rotatable brush. The term “agitator” is used herein in a broad sense to mean any type of implement that will scrub a bare floor and can include brushes, either stationary or movable with respect to the base assembly, fibrous or cloth pads, sponges, and the like. 
     The bare floor cleaner according to invention offers several advantages to a user. The cleaner is capable of performing, with one machine and without attachments, the several steps involved in effectively cleaning a bare floor surface. The agitator assembly, with the aid of fresh and optionally warm cleaning solution, proficiently removes dirt, dust, and debris adhered to the surface to be cleaned without requiring any physical exertion from a user. The cam assembly and diverter valve permit facile movement between dry pickup, wet scrubbing, and wet pickup modes with a single switch conveniently located on the handle assembly. The cleaning solution trigger is also disposed on the handle assembly; therefore, the operational controls of the bare floor cleaner can easily be accessed during use. Additionally, the recovery and supply tanks are easily removable from the handle assembly for quick emptying and filling, respectively. Further, any clogs that develop in the nozzle assembly are visible due to the shapes of the suction paths and the transparent nature of the nozzle walls, and the nozzle is quickly removable from the base assembly for removal of the clogs. Moreover, very little cleaning solution remains on the surface after wet pickup, with or without wet scrubbing. As a result, the surface readily dries and the room(s) can be used in a normal fashion. 
     The cleaning apparatus invention has been disclosed with respect to cleaning bare floors. However, the cleaner described herein can also be used on other floors and other surfaces, including carpets, upholstery, and the like, without departing from the scope of the invention. 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 combination are possible with the scope of the foregoing disclosure without departing from the spirit of the invention, which is defined in the appended claims.