Abstract:
A floor care machine is provided that includes a replaceable floor care element that is quickly and easily attached and detached. To attach the floor care element, an operator positions the floor care element under a motor and lifts the element up to a motor interface. The motor interface aligns with a complementary interface of the floor care element.

Description:
This application is related to U.S. patent application Ser. No. 11/059,663, now U.S. Pat. No. 7,533,435; U.S. Patent Application Publication No. 2006/0064844, filed Oct. 17, 2005; and U.S. Patent Application Publication No. 2009/0094784, filed Oct. 5, 2007, the entire disclosures of which are incorporated by reference herein. 
     FIELD OF THE INVENTION 
     Embodiments of the present invention relate to a floor care machine that employs an easily attachable and detachable floor care element (e.g., a pad, a brush, etc.). 
     BACKGROUND OF THE INVENTION 
     Machines that perform floor care operations such as burnishing, cleaning, polishing, sweeping, scrubbing, etc. include a replaceable floor care element that contacts the floor. In some instances a disk shaped element is provided that contacts the floor and rotates about an axis perpendicular to the floor. Attaching such a floor care element to the bottom of an often heavy floor care machine is time consuming and difficult. Thus, it is desirable to provide floor care elements that are easily attached and detached from the floor care machine. 
     Burnishing is a process wherein a floor surface is polished after a layer of wax or other finishing material has been added to the floor. Burnishing is performed with a burnishing pad that rotates at a high rate of speed, such as 1,500 RPMs or more. Debris generated by the burnishing process is captured by a shroud that surrounds the burnishing pad. The debris is suctioned from the shroud into a collection receptacle. As burnishing pads wear, regular inspection and replacement is a necessity, so it is desirable to make pad replacement easy and safe. 
     Burnishing machines are manufactured in two primary forms—self propelled walk-behind and motor-driven. Small walk behind machines include a burnishing pad located under a motor and are very common but are often difficult to control. Such machines also generate uncomfortable vibrations that adversely affect the user. The advantage of self propelled walk-behind machines is that the burnishing pad is easy to access and replace. 
     Conversely, larger, motor-driven machines provide enhanced control and reduce uncomfortable vibrations. These types of machines may be walk-behind or ride-on. As alluded to above, one disadvantage of larger machines is that the burnishing assembly, which is usually positioned beneath the machine, is difficult to access for inspection and replacement. More specifically, cleaning or burnishing pads are often centered under the machine to protect the pad and associated driving mechanisms from damage. In addition, placing the pad under the machine minimizes the length of the machine, which is desirable. However, in these configurations removal and replacement of the pad must be performed as a “blind” operation. 
     Thus, there is a long felt need to provide a floor care machine that includes a pad driver mechanism that facilitates attachment and detachment of a floor care element. The following disclosure describes an improved pad interconnection system that selectively receives a burnishing pad assembly and facilitates attachment and detachment of the same. 
     SUMMARY OF THE INVENTION 
     It is one aspect of the present invention to provide a floor care machine. More specifically, one embodiment of the present invention includes a chassis that supports a housing. The housing conceals most of the internal components of the floor care machine and provides a standing, leaning, or sitting location for the operator. The chassis also supports a powered steering device that enhances maneuverability of the floor care machine Further, the chassis of one embodiment of the present invention is associated with wheels positioned in such a way to allow the floor care machine to rotate about 360 degrees without substantially traversing in any other direction. 
     It is yet another aspect of the present invention to provide a floor care machine that can be used in various floor maintenance operations. In one embodiment, the present invention is able to accommodate a plurality of floor care elements to perform a variety of floor care operations. It is envisioned that the floor care elements be capable of quick removal and replacement such that the purpose of the machine can be quickly changed. Thus, it is contemplated, that this system may be used for a plurality of cleaning or floor treatment operations, such as burnishing, scrubbing, etc. 
     It is another aspect of one embodiment of the present invention to provide a floor care machine that employs an easily removable burnishing assembly. More specifically, one embodiment of the present invention employs a motor that provides rotational energy to an attached burnishing assembly. The motor is supported by a linkage interconnected to the chassis and a spring that effectively allows the burnishing assembly to “float” on the floor. As one of skill in the art will appreciate, the amount of burnishing pressure applied to a floor is a function of the motor weight and the spring tension. 
     The burnishing assembly of one embodiment of the present invention includes a pad carrier that accommodates a burnishing pad. A pad driver, which is also associated with the pad carrier, receives a driver hub that is interconnected to the motor. The pad driver includes a recess or opening for receipt of a driver hub. In operation, the burnishing assembly is placed under the driver hub and lifted, which locates the driver hub into the recess of the pad driver. Slight rotation of the burnishing assembly will attach it to the driver hub. 
     It is a related aspect of embodiments of the present invention to provide a way of interconnecting the burnishing assembly to the floor care machine in quick and efficient manner. More specifically, the burnishing assembly is installed and removed primarily by feel. An instructional decal on the burnishing assembly may be provided to assist the operator in replacing the burnishing assembly. Initially, the driver hub is locked to prevent rotation. After it is locked, a slight counterclockwise rotation of the assembly will disengage the burnishing assembly from the driver hub. Similarly, to install a new burnishing assembly, the pad driver is placed generally under the driver hub and lifted where the recess of the pad driver will eventually contact with an outer surface of the driver hub. 
     In one embodiment of the present invention, the recess and the driver hub are shaped such that the driver hub will automatically align the burnishing assembly. A slight rotation of the burnishing assembly in a clockwise direction will temporarily fix the pad driver to the driver hub. One of skill in the art will appreciate that the burnishing assembly can be removed by clockwise rotation and attached by a counterclockwise rotation. Complete interconnection between the pad driver and the driver hub occurs when the operator initiates rotation of the burnishing assembly. 
     It is another aspect of the present invention to provide a floor treatment apparatus that reduces vibration. As briefly mentioned above, it is desirable to maintain vibrations generated by the burnishing operation at a level that does not reduce performance or cause operator discomfort. The burnishing assembly of embodiments of the present invention minimizes vibration in three ways. First, the center of gravity of the burnishing assembly is coaxial with the motor shaft, which balances the rotating mass. Second, the configuration of the pad mounted to the burnishing assembly ensures that it is always correctly placed on the driver hub. Third, the driver hub is interconnected to the pad drive with zero clearance, which is achieved by employing a driver hub with a tapered outer surface that fits within a tapered recess of the pad driver. The driver hub may also include a plurality of outwardly extending arms that interface with ramps integrated into the pad driver to firmly seat the driver hub into the pad driver. Indeed, the seating effect may increase as the assembly is rotated clockwise or counterclockwise. 
     It is another aspect of the present invention to provide a shroud positioned about the burnishing pad that contains debris generated by the burnishing process. Many burnishing assemblies require that the pad pressure be set before burnishing begins and/or adjusted during operation. However, as the thickness of the pad decreases, applied pressure and shroud drag also changes. Pressure increases rotational resistance to the battery-powered motor and thus negatively affects floor care machine run time. Further, too much or too little pad pressure will yield less than ideal floor finish. One embodiment of the present invention employs a two-piece “floating” shroud system that works in conjunction with the floating burnishing assembly described above to help eliminate these issues. 
     The floating shroud system of one embodiment of the present invention maintains a constant contact with the floor so that dust generated by the burnishing process is contained. Further, as the shroud floats relative to the motor, it is not affected by the thickness of the pad which can change through use and replacement. In one embodiment of the present invention the shroud is comprised of an inner fixed shroud that is interconnected to the motor and an outer movable shroud that contacts the floor via a soft nylon bristled skirt. The main benefit of a two-piece shroud is that it automatically maintains a constant pad pressure and shroud pressure on the floor being burnished. More specifically, as the pad wears, the distance between the motor and interconnected fixed shroud to the floor will decrease. If the outer shroud was fixed, this would cause the shroud to “drag” across the floor. Here, however, as the pad wears, the outer shroud will separate from the inner shroud, thereby maintaining the amount of contact applied to the floor. Again, pad pressure is controlled independently by springs with a low spring rate. Additionally, when a newer (thicker) pad is installed, there are no pressure settings to adjust. These features keep current usage constant as the pad wears which will keep the battery run time optimized. 
     It is another aspect of the present invention to provide a floor care machine, comprising: a chassis having a front and a back and with a lower surface, a front surface adjacent the front, an upper surface, a rear surface adjacent the back, a left surface and a right surface; a first wheel operably interconnected to the lower surface adjacent to the left surface and located closer to the rear surface than the front surface; a second wheel operably interconnected to the lower surface adjacent the right surface and located closer to the rear surface than the front surface; a platform located substantially between at least a portion of the right surface, at least a portion of the left surface and extending rearwardly from a portion of the rear surface, the platform also substantially located within the chassis and positioned substantially directly above an axis extending between the center of the first wheel and the center of the second wheel and wherein the platform includes a top surface which is adapted to receive the feet of an operator, a throttle and an operator presence device operatively connected to and which selectively interrupts operation of the throttle; a powered wheel operably connected adjacent the lower surface of the chassis; a steering mechanism substantially housed within the chassis and having a portion that is accessible by an operator; a motor associated with at least one of the chassis and the housing, the motor having a rotating shaft interconnected to a driver hub, the driver hub having a first outer surface; and a floor care element interconnected to the motor, the floor care element comprised of a pad carrier having a pad on one side and a pad driver on an opposite side, the pad driver having an opening defined by a second surface that is complementary to the first surface of the driver hub. 
     It is still yet another aspect of the present invention to provide a burnishing assembly, comprising: a pad carrier having a first side and a second side; a burnishing pad interconnected to the second side; a pad driver interconnected to the first side, the pad driver having an internally-disposed opening with first mating surface and an upper surface that encircles an upper edge of the first mating surface, the upper surface having a plurality downwardly-angled portions that terminate at corresponding openings, the openings associated with protrusions that extend towards an end of the downwardly-angled portions, the protrusions interconnected to a vertical surface, which is also interconnected to the pad carrier, to define a cavity that is adapted to receive a component of a complementary outer profile. 
     It is another aspect of the present invention to provide a method of interconnecting a floor care element to a floor care machine, comprising: raising a motor associated with the floor care machine to move a pad of the floor care element away from a floor; positioning the floor care element under the motor of the floor care machine; raising the floor care element to associating an interface thereof with a driver hub of the motor; positioning arms of the driver hub within openings of the interface; further raising the floor care element such that complementary of the interface and the drive hub engage; rotating the floor care element a predetermined amount; and engaging a portion of the arm onto a retaining member of the interface. 
     The Summary of the Invention is neither intended nor should it be construed as being representative of the full extent and scope of the present invention. Moreover, references made herein to “the present invention” or aspects thereof should be understood to mean certain embodiments of the present invention and should not necessarily be construed as limiting all embodiments to a particular description. The present invention is set forth in various levels of detail in the Summary of the Invention as well as in the attached drawings and the Detailed Description of the Invention and no limitation as to the scope of the present invention is intended by either the inclusion or non-inclusion of elements, components, etc. in this Summary of the Invention. Additional aspects of the present invention will become more readily apparent from the Detail Description, particularly when taken together with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and together with the general description of the invention given above and the detailed description of the drawings given below, serve to explain the principles of these inventions. 
         FIG. 1  is a side elevation view of the floor care machine of one embodiment of the present invention; 
         FIG. 2  is a cross section of  FIG. 1 ; 
         FIG. 3  is a cross section of  FIG. 2 ; 
         FIG. 4  is a detailed view of  FIG. 2  showing a burnishing assembly; 
         FIG. 5  is a top perspective view of the burnishing assembly; 
         FIG. 6  is a cross section of  FIG. 5 , wherein a shroud has been omitted for clarity and wherein a driver hub has been inserted into a pad driver; 
         FIG. 7  is a cross section of  FIG. 5 , wherein the shroud has been omitted for clarity and wherein the driver hub has been locked into the pad driver; and 
         FIG. 8  is a bottom perspective view of the burnishing assembly showing the engagement of a driver hub to a pad driver. 
     
    
    
     To assist in the understanding of one embodiment of the present invention, the following list of components and associated numbering found in the drawings is provided herein: 
     
       
         
               
               
             
               
               
             
           
               
                   
               
               
                 # 
                 Component 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 2 
                 Floor care machine 
               
               
                 6 
                 Chassis 
               
               
                 10 
                 Front wheel 
               
               
                 14 
                 Rear wheels 
               
               
                 18 
                 Housing 
               
               
                 22 
                 Burnishing assembly 
               
               
                 26 
                 Motor 
               
               
                 30 
                 Shroud 
               
               
                 34 
                 Bracket 
               
               
                 38 
                 Linkage 
               
               
                 42 
                 Support spring 
               
               
                 48 
                 Platform 
               
               
                 50 
                 Pad 
               
               
                 54 
                 Hose 
               
               
                 58 
                 Pad driver 
               
               
                 62 
                 Driver hub 
               
               
                 66 
                 Pad carrier 
               
               
                 70 
                 Ramp 
               
               
                 74 
                 Opening 
               
               
                 78 
                 Protrusions 
               
               
                 82 
                 Stop surface 
               
               
                 86 
                 Upper surface 
               
               
                 90 
                 Retaining members 
               
               
                 94 
                 Arm 
               
               
                 98 
                 Locking mechanism 
               
               
                 102 
                 Recess 
               
               
                 106 
                 Outer surface 
               
               
                 110 
                 Opening 
               
               
                 114 
                 Inner surface 
               
               
                 118 
                 Outer surface 
               
               
                 122 
                 Fixed shroud 
               
               
                 126 
                 Outwardly extending lip 
               
               
                 130 
                 Inwardly extending lip 
               
               
                 134 
                 Movable shroud 
               
               
                 138 
                 Skirt 
               
               
                   
               
             
          
         
       
     
     It should be understood that the drawings are not necessarily to scale. In certain instances, details that are not necessary for an understanding of the invention or that render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein. 
     DETAILED DESCRIPTION 
     Referring now to  FIGS. 1-4 , a floor care machine  2  of one embodiment of the present invention is shown that includes a chassis  6  that supports a front wheel  10  and two rear wheels  14 . The chassis  6  also supports a housing  18  that conceals a majority of the internal componentry of the floor care machine  2 . Positioned between the front wheel  10  and the rear wheels  14  is a motor  26  with an interconnected burnishing assembly  22 . 
     The burnishing assembly  22  is surrounded by a shroud  30 , which will be described in further detail below. The motor  26  is supported by a bracket  34  and associated linkage  38  that is interconnected to the chassis  6 . A support spring  42  controls the downward force of the motor  26  and interconnected burnishing assembly  22 , which allows the burnishing assembly to “float” on the floor. The floor treatment machine may also include a platform  48  that accommodates an operator. 
     The burnishing assembly  22  is capable of at least two positions of use: 1) elevated, which allows the floor care machine to be moved easily, and 2) lowered, which engages a pad  50  to the floor. During high speed polishing, debris will be generated and captured by the shroud  30 . The debris is suctioned from the shroud by the evacuator hose  54 . As the burnishing process continues, the pad  50  will eventually wear and require replacement, which will be described in further detail below. 
       FIGS. 3-8  illustrate how the burnisher assembly  22  of one embodiment of the present invention is interconnected and removed from the motor  26 . The burnisher assembly  22  includes a pad driver  58  that interconnects to a motor-driven drive hub  62 . The pad driver  58  is also interconnected to a pad carrier  66 . The opposite side of the pad carrier  66  receives the pad  50 . In some embodiments of the present invention the pad driver  58  and pad carrier  66  are made of a plastic material such that the entire burnishing assembly  22  is replaceable. The pad driver  58  includes a plurality of ramps  70  that are separated by openings  74 . The pad driver  58  also includes protrusions  78  that extend into the openings  74  and are angled slightly upwardly relative to a top surface of the pad carrier  66 . The protrusions  78  extend from stop surfaces  82  and extend downwardly from an upper surface  86  of the pad driver  58  to contact the pad carrier  58 . Further, the underside of the pad driver  58  includes retaining members  90  which will be described in further detail below. 
     To interconnect the burnishing assembly  22  to the floor care machine, the drive hub  62  must be interconnected to the pad driver  58 . Initially, the motor  26  and associated burnishing assembly  22  are raised wherein the pad  54  is elevated above the floor. The burnishing assembly  22  is rotated to align arms  94  of the driver hub  62  with the openings  74  in the pad driver  58 , which allows the burnishing assembly  22  to separate from the driver hub  62 . As the burnishing assembly is interconnected to a motor shaft that is apt to rotate, in some instances a locking mechanism  98  must first be used so that the burnishing assembly  22  will rotate independently of the drive hub  62 . The locking mechanism  98  preferably has a hexagonal recess  102  that selectively receives the hexagonal outer surface  106  of the driver hub  62 . When engaged, the driver hub  62  is not able to rotate, which allows the burnishing assembly  22  to rotate relative to the fixed driver hub  62 . 
     To interconnect a new burnishing assembly  22  to the driver hub  62 , the burnishing assembly  22  is first positioned directly below the driver hub  62 . Again, to prevent rotation of the driver hub  62 , the locking mechanism  98  may be actuated wherein the outer surface  106  of the driver hub  62  is fit within the recess  102  of the locking mechanism  98 . Next, the burnishing assembly  22  is lifted upwardly to insert the driver hub  62  within an opening  110  of the pad driver  58 . With specific reference to  FIG. 6 , the inner surface  114  of the pad driver  58  and the outer surface  118  of the driver hub  62  are complimentary wherein when they are brought together they self-align and center. In one embodiment of the present invention the outer surface  118  of the driver hub  62  is frusto-conical, as such a shape allows for the burnishing assembly  22  to be self-aligning within a complementary surface as it is raised into place, which aids the operator in interconnecting the burnishing assembly “in the blind”. However, other shapes could be utilized with the driver hub with equal effect. 
     As the burnishing assembly  22  is raised, openings  74  of the pad driver  58  accept the arms  94  of the driver hub  62 . If the arms  94  are not rotationally aligned with the opening  74 , the arms  94  will contact the ramps  70  provided on the upper surface  86  of the pad driver  58 . Rotation of the burnishing assembly  22  will then needed to guide the arms  94  into the openings  74 . Once the arms  94  are fitted through the openings  74 , the burnishing assembly  22  may be completely raised into place and rotated slightly to position the arms  94  beneath the protrusions  78  associated with the openings  74  of the pad driver  58 . The protrusions  78  employ an upwardly angled surface that correspond with downwardly-angled surfaces of the arms  94 . The arms  94  are rotated further until they contact the retaining features  90 . In one embodiment of the present invention the retaining features  90  are rubber overwrapped screws that frictionally engage a portion of the arms  94  to keep the burnishing assembly  22  is temporarily fixed to the driver hub  62 . After this step, the pad assembly is interconnected to the driver hub  62  and the locking mechanism  98  may be transitioned away from the driver hub. 
     To finalize the interconnection of the burnishing assembly  22  to the driver hub  62 , the motor is initiated to rotate the driver hub  62  at high speeds which will dislocate the arms  94  from the retaining members  90  and urge the arms against a corresponding stop surface  82 . The rotational forces generated by the arms  94  will be directly transferred to the pad driver  58 , which will in turn spin the burnishing assembly  22 . The complementary nature of the outer surface  106  of the driver hub  62  and the inner surface  114  of the opening  110 , and the complementary nature of the arm  94  and the protrusion  78  provide a snug-zero tolerance fit between the driver hub  62  and the pad driver  58  which will reduce vibrations generated by the spinning pad  50 . 
     Referring again to  FIGS. 3 and 4 , a two piece shroud system  30  employed by embodiments of the present invention is shown. Here, the shroud includes a fixed upper shroud  122  that is secured to the motor  26  and/or bracket  34 . As the pad  50  wears, the motor  26 , burnishing assembly  22 , and fixed shroud  122  will move closer to the floor. The fixed shroud  122  includes an outwardly-extending lip  126  that engages an inwardly extending lip  130  of an outer, movable shroud  134 . As the inner shroud  122  moves closer to the floor, engagement between the lips of the outer shroud  134  and inner shroud  122  will break and the location of the outer shroud  134  will be maintained. No loss of suction occurs because a seal is maintained between the fixed shroud and the outer shroud. This feature of the invention has advantages over the prior art as the outer shroud  134  is not forced against the floor as the pad wears and thus contact and associated drag between the shroud and the floor is maintained. The outer shroud  134  also includes a flexible skirt  138  that accommodates deflections of the outer shroud while ensuring that the majority of debris generated by the pad  50  is captured. 
     While various embodiments of the present invention have been described in detail, it is apparent that modifications and alterations of those embodiments will occur to those skilled in the art. However, it is to be expressly understood that such modifications and alterations are within the scope and spirit of the present invention, as set forth in the following claims. Further, the invention(s) described herein is capable of other embodiments and of being practiced or of being carried out in various ways. In addition, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.