PATENT ABSTRACT
A floor sweeper is disclosed having a removable debris compartment. The compartment has a front portion that is at least partially open. A pair of counter-rotating brushes are located forward of the debris compartment for delivering debris directly through the front portion into the debris compartment. A cover that strips debris from the brushes and that also directs stripped debris extends over the brushes. The cover has an air spoiler forward of the brushes. A strip for blocking debris is located opposite of the cover and is located substantially entirely the length of and between the brushes.

PATENT DESCRIPTION
RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 61/089,967, filed Aug. 19, 2008, which is fully incorporated by reference herein. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a floor sweeper that is effective on a variety of different floor types and a variety of different floor materials. 
     BACKGROUND OF THE INVENTION 
     Floor sweepers are well-known devices capable of sweeping debris from the floor into the sweeper resulting in a cleaner floor. The floor debris, having been collected within the sweeper, can then be disposed of from this convenient single location. 
     Floor sweepers often have brushes used to collect the debris from the floor. The brushes may be electrically powered, via connection to an outlet or by batteries. The brushes may also be rotated manually by virtue of the sweeper being pushed across the floor by an operator. 
     Battery powered sweepers are well-known products, with many examples available for the consumer market, and a smaller number of sweepers available for the commercial market. However, all of the available consumer and commercial products have performance limitations. 
     For example, the available sweepers all lack the ability to effectively pick up debris on both hard floors as well as carpeted floors. Those skilled in the art know that debris collection on carpeted floors is relatively easy, but the prior art sweepers are plagued by a number of problems when used on hard floors. 
     On hard floors, the prior art sweepers disadvantageously blow and scatter light debris forward, behind and/or to the sides and away from the sweeper. Additionally, these sweepers cannot pick up small and/or light debris, such as small amounts of fine sand and/or debris such as “hole punch dots” and similar debris. 
     In view of the disadvantages of the prior art designs, a sweeper that does not blow debris away from the sweeper and that is capable of picking up small and light debris on any surface is required. 
     SUMMARY OF THE INVENTION 
     In one embodiment of the invention a floor sweeper is provided comprising a removable debris compartment having a front portion that is at least partially open. A pair of counter-rotating brushes are located forward of the debris compartment for delivering debris directly through the front portion into the debris compartment. A cover is provided for stripping debris and directing debris from the brushes. The cover may have an air spoiler forward of the brushes. A debris blocking strip may be located opposite of the cover and extend substantially the entire length of the brushes. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above advantages of the present invention will become readily apparent to those skilled in the art from the following detailed description when considered in the light of the accompanying drawings in which: 
         FIG. 1  is a schematic perspective view of one embodiment of the present invention; 
         FIG. 2  is a schematic perspective view of a portion of the invention of  FIG. 1  with a cover removed; 
         FIG. 3  is a schematic perspective view of the device of  FIG. 2  with the cover in place and a debris compartment exploded from the sweeper; and 
         FIG. 4  is a schematic cutaway side view of the device depicted in the foregoing figures. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     It is to be understood that the invention may assume various alternative orientations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification are simply exemplary embodiments of the inventive concepts defined herein. Hence, specific dimensions, directions or other physical characteristics relating to the embodiments disclosed are not to be considered as limiting, unless the expressly stated otherwise. 
     Turning now to  FIG. 1 , one construction embodying a sweeper  10  of the present invention comprising a handle portion  12  and a base portion  14  is depicted. The handle portion  12  is pivotally attached to the base portion  14  to permit the handle portion to be selectively angled with respect to the base portion  14 . 
     In  FIG. 1 , the handle portion  12  is depicted in what will be referred to as a stowed position  16 . The stowed position  16  is a position in which the handle portion  12  is approximately perpendicular to the base portion  14 . When the handle portion  12  is in the stowed position  16 , the sweeper  10  is typically not in use. When the handle portion  12  is pivoted from the stowed position  16  rearwardly with respect to the base portion  14 , the handle portion  12  is in a use position (not shown). 
     An electrical switch (not shown), located in the base portion  14 , is connected to the handle portion  12 . The switch is connected to the handle portion  12  so that when the handle portion  12  is in the stowed position  16 , the switch is in the off position. When the handle portion  12  is moved from the stowed position  16 , the switch is turned on. The angle, with respect to the base portion  14 , that the handle portion  12  turns the switch on and off can be varied. A hand operated switch on the handle portion  12  may also be utilized. 
     The electrical switch is connected between a battery  18  and a motor  20  in the base portion  14 . The battery  18  is preferably located adjacent the motor  20  as shown in  FIG. 2 . More preferably, the battery  18  is located between the handle portion  12 , the motor  20  and a debris compartment  22  that will be described in more detail below. 
     The battery  18  may be removably mounted in the base portion  14  to permit convenient replacement and repair. Regarding replacement, the battery  18  is preferably a rechargeable-type battery  18  that may be recharged in a separate charging unit (not shown). Thus, it can be appreciated that it may be desirable for multiple batteries to be on hand when operating the sweeper  10 ; one in the sweeper  10  itself and one or more in the separate charging units. 
     The motor  20  is located between the handle portion  12  and the debris compartment  22  and beside the battery  18 . The motor  20  has a drive shaft  24  with a drive wheel  26  secured to the shaft  24 . The drive shaft  24  preferably extends in an outboard direction with respect to the base portion  14 . The drive wheel  26  may have a groove  28  in it for receiving a belt  30 . 
     The belt  30  is preferably a closed loop-type belt  30 . It may be constructed of any elastomer-like material with a high degree of durability. 
     The belt  30  extends forward from the motor  20  along an outboard portion  32  of the debris compartment  22 . The belt  30  engages with a tensioning wheel  34  adjacent a lower forward portion  36  of the debris compartment  22 . The tensioning wheel  34  is substantially aligned with the drive wheel  26 . The tensioning wheel  34  permits a predetermined amount of tension to be provided in the belt  30 . 
     Immediately forward of the debris compartment  22  is a rear rotating brush  38 . The rear brush  38  is comprised of a tubular central section  40  with a plurality of brushes  42  extending substantially perpendicularly from the central section  40 . Each of the brushes  42  extends from the central section  40  in a line such that a single brush  42  preferably extends substantially from a first end (not shown) of the rear brush  38  to a second end (not shown) of the rear brush  38 . 
     A driven wheel  44  is located on the first end of the rear brush  38  and it is substantially aligned with the tensioning wheel  34 . The driven wheel  44  is attached to the rear brush  38  such that when the wheel  44  is rotated, it rotates the central section  40  and the brush  38  as well. 
     Forward of the rear brush  38  is a forward brush  46 . The forward brush  46  may have an identical tubular center section  48  and a plurality of brushes  50  as compared to the rear brush  38 . Alternatively, the number of brushes and/or the pattern of the brushes may be different than the number and pattern of brushes for the rear brush  38 . 
     The center section  48  of the forward brush  46  has a first end  52  and a second end  54 . The first end has a driven wheel  56  secured thereto. The driven wheel  56  is aligned with the driven wheel  44  on the rear brush  38 . 
     Preferably, the belt  30  is in contact with a lower portion  58  of the tensioning wheel  34 . From the lower portion  58  of the tensioning wheel  34 , the belt  30  extends upwardly to extend over an upper portion  60  of the rear brush driven wheel  44 . From the rear brush driven wheel  44 , the belt  30  extends downwardly to initially engage a lower portion  62  of the driven wheel  56  of the forward brush  46 . The belt  30  extends around a forward portion  64  of the forward brush driven wheel  56  to an upper portion  66  of the wheel  56 . From the forward portion  64  of the forward brush driven wheel  56 , the belt  30  returns to the drive wheel  26  on the motor  20 . 
     The motor  20  rotates the belt  30  in the direction of the arrow shown on  FIG. 2 . It can be appreciated that the depicted belt rotation results in the rear brush  38  rotating in a first direction and the forward brush  46  rotates in a second, opposite direction. Preferably, the forward brush  46  rotates in a counterclockwise motion as seen from  FIG. 2 , while the rear brush rotates in a clockwise motion, also as seen from  FIG. 2 . While clock rotation directions of the brushes  35 ,  46  have been mentioned above, the brushes  38 ,  46  of the present invention can rotate in the opposite directions. Preferably, however, regardless of the specific clock direction of rotation, the brushes  38 ,  46  rotate in opposite directions from one another. 
     While a belt  30  drive has been described and is depicted in the figures, it is within the scope of the invention to drive the forward and rear brush  38 ,  46  via one or more gears (not shown) connected to the motor  20 . It is also within the scope of the invention to use a combination of gears and a belt (neither of which are shown) to drive the brushes  38 ,  46 . 
       FIGS. 1 ,  2  and  3  depict one embodiment of the debris compartment  22 , but other shapes and sizes are within the scope of the invention. The debris compartment  22  is preferably located immediately behind the rear brush  38  and forward of the motor  20  and battery  18 . The debris compartment  22  has an upper portion  68 , a lower portion  70 , side portions  72  and a front portion  74 . The entire length of the front portion  74 , from the upper portion  68  to the lower portion  70 , is preferably open to receive debris from the brushes  38 ,  46 . The portions  68 ,  70  and  72  form a box-like structure for temporarily storing debris. 
     Debris collected by the brushes  38 ,  46  remains within the compartment  22  for temporary storage. The debris compartment  22  is selectively removable from the sweeper  10  for maintenance, repair, replacement and emptying. 
     More specifically, the debris compartment  22  is designed to be located within, and removed from, the base portion  14  of the sweeper  10  without any tools or bolts, screws or the like. Effectively, the debris compartment  22  drops in a portion of the base portion  14  having a complimentary shape to the compartment  22 . It can be picked up and removed just as easily from the base portion  14 . The ease at which the debris compartment  22  can be located within and removed from the base portion  14  facilitates effortless and quick emptying. 
     A housing  76  covers the sweeper  10  preferably in conjunction with the debris compartment  22 . The housing  76  may be of a one-piece construction or it may be comprised of multiple pieces. Preferably, the housing  76  covers the motor  20 , the battery  18 , belt  30  and the drive and driven wheels,  26 ,  44 ,  56  as well as the brushes  38 ,  46 . 
     The housing  76  comprises a brush cover  78 . The brush cover  78  preferably covers at least the forward brush  46  and it may cover, as shown in the figures, the rear brush  38  as well. The portion of the brush cover  78  located over the brushes  38 ,  46  has at least three functions. 
     First, the brush cover  78  functions as a housing to protect the brushes  38 ,  46 , prevent items from falling into the brushes  38 ,  46  from above and it provides an aesthetically pleasing cover over the brushes  38 ,  46 . 
     Second, the brush cover  78  is designed to fit closely to the forward brush  46 . By locating the cover  78  in close proximity to the forward brush  46 , the cover  78  is able to strip debris from the sets of brushes  50  on the forward brush  46  as they pass beneath it. 
     It is preferable to strip the debris from the forward brush  46  to minimize the chance that the brush  46  will become clogged. A brush  46  clogged with debris is undesirable at least for the reasons that the brush  46  loses its ability to pick up new debris on the floor and it may result in debris scattering from the brush  46  on to the floor. 
     Preferably, a bottom surface  80  of the cover  78  is located between approximately 0.01 inches and approximately 0.1 inches from an outside diameter  82  of brushes  50  on the forward brush  46 . More preferably, the bottom surface  80  of the cover  78  is located approximately 0.060 inches from the outside diameter  82  of the brushes  50  on the forward brush  46 . 
     The third function of the housing  76  is to direct the debris that has been stripped from the forward brush  46  into the rotating brushes  42  of the rear brush  38 . The rear brush  38 , rotating in an opposite direction of the forward brush  46 , then directs the debris into the open, forward portion  64  of the debris compartment  22 . 
     A brush strip  84  is preferably located between the two rotating brushes  38 ,  46 . The brush strip  84  is a relatively thin, in terms of width, strip of material, such as plastic or metal, that is located substantially entirely between the brushes  38 ,  46  and substantially perpendicular to a floor surface  86 . An upper end portion  88  of the strip  84  is secured between the brushes  38 ,  46  while a lower end portion  90  extends downwardly toward, and may be in contact with, the floor  86 . Preferably, the strip  84  extends downwardly below the outer diameter of the brushes  38 ,  46 . The strip  84  can extend between the entire length of the brushes  38 ,  46 , or it can extend only selectively between the brushes  38 ,  46 . 
     The brush strip blocks  84  rearwardly travelling debris from the forward brush  46  from being propelled behind the sweeper  10 . The brush strip  84  also blocks forwardly travelling debris from the rear brush  38  from being propelled in front of the sweeper  10 . 
     A spoiler  92  is preferably located forward of the forward brush  46 , as shown in  FIG. 4 . The spoiler  92  may be located on the brush cover  78 . The spoiler  92  may be integrally formed with the brush cover  78  or it may be separately attached to the cover  78 . 
     The spoiler  92  is designed to modify an area of high pressure air that is generated in front of the sweeper  10  when the brushes  38 ,  46 , and in particular the forward brush  46 , rotate. More specifically, the spoiler  92  is designed to reduce or minimize the region of high pressure. 
     The rotating forward brush  46  moves air outward from the outer diameter of the brush bristles  50 , in a generally tangential direction. This air, which is the result of a pressure differential measured from an area immediately surrounding the brush  46  to an area some distance away from the brush  46 , tends to push light debris, such as dust, away from the sweeper  10 . 
     The spoiler  92  extends into the stream of air from the brush  46  to disrupt the stream. By disrupting the airstream, the ability of the airstream to push debris, and in particular light debris, away from the sweeper  10  is greatly diminished, if not eliminated. It can be appreciated that debris which is desired to be collected can thereby be readily collected by the sweeper  10 , instead of being blown ahead of or generally away from the sweeper  10 . 
     A first portion  94  of the spoiler  92  preferably extends inwardly from the housing  76  toward the forward brush  46  and it is substantially parallel to the floor  86 . The amount by which the spoiler  92  may extend from the housing  76  may vary, however, lengths ranging between approximately 0.1 and approximately 0.2 inches have been found to be effective. 
     A second portion  96  of the spoiler  92  may also be used to reduce an opening  98  between the housing  76  and the floor  86  to a dimension that permits appropriately large debris to enter the sweeper  10 , but which is small enough to reduce or effectively eliminate debris moving air flow from the forward brush  46 . The opening  98  may be between approximately 0.250 inches and approximately 0.9 inches. An opening  98  of approximately 0.625 inches has been found to be particularly advantageous, however, an opening of other dimensions may be used. 
     The base portion  14  is supported on a plurality of wheels. A first set of wheels  100  is preferably located rearward of the battery  18  and the motor  20 . A second set of wheels  102  is preferably located between the forward brush  46  and the rear brush  38 . The wheels  100 ,  102  permit the sweeper  10  to roll over a floor surface  86 , including most known manmade and natural flooring materials, at a height predetermined to be effective for the forward and the rear brushes  46 ,  38  to collect debris from the floor surface  86 . 
     In accordance with the provisions of the patent statutes, the present invention has been described in what is considered to represent its preferred embodiments. However, it should be noted that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope.