Patent Publication Number: US-11382479-B2

Title: Floor cleaning machine

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application No. 62/587,641, filed Nov. 17, 2017, the entire contents of which are hereby incorporated by reference herein. 
    
    
     BACKGROUND 
     The present invention relates to floor cleaning machines, and particularly to powered floor sweepers. 
     SUMMARY 
     The invention provides, in one aspect, a floor cleaning machine including a rotary brush rotatable about a first axis and a brushroll rotatable about a second axis. The brush and the brushroll are configured to convey debris toward a collection bin. The floor cleaning machine also includes a suction source configured to produce a first suction zone between the brush and the brushroll and a second suction zone in the collection bin. In some embodiments, the brush, the brushroll, and the suction source are powered by a rechargeable power tool battery pack. 
     In some embodiments, the invention provides a floor cleaning machine including a housing having a front end and a rear end, and a rotary brush coupled to the housing for rotation with respect to the housing. A collection bin is configured to receive debris from the rotary brush and a debris intake is in fluid communication with the collection bin. A motor rotates the rotary brush, and a power source supplies power to the motor. A suction source is in fluid communication with the collection bin to draw debris into the debris intake and to direct the debris into the collection bin. A projection is positioned adjacent the rotary brush and the debris intake engage bristles of the rotary brush to dislodge debris from the bristles, so that the suction source is configured to draw debris dislodged from the bristles of the rotary brush into the debris intake. 
     In some embodiments, the invention provides a floor cleaning machine including a housing having a front end and a rear end and a wheel coupled to the housing to facilitate moving the machine along a surface to be cleaned. A rotary brush is coupled to the housing for rotation with respect to the housing, and a collection bin is configured to receive debris from the rotary brush. The collection bin includes a front wall positioned between the front end of the housing and the rear end of the housing, the front wall defining an entry opening, a rear wall positioned adjacent the rear end of the housing, and an upper wall extending between the front wall and the rear wall. The upper wall is oriented at an oblique angle with respect to the surface being cleaned, such that a cross-sectional area of the collection bin increases in a direction from the entry opening in the front wall toward the rear wall. A debris intake is in fluid communication with the entry opening in the front wall of the collection bin. A motor rotates the rotary brush, and a power source supplies power to the motor. A suction source is configured to draw debris into the debris intake and direct the debris into the collection bin, such that debris directed into the entry opening in the front wall of the collection bin is directed along the oblique upper wall toward the rear wall. 
     In some embodiments, the invention provides a floor cleaning machine including a housing having a front end and a rear end, and a rotary brush coupled to the housing for rotation with respect to the housing. A collection bin receives debris from the rotary brush, and a debris intake is in fluid communication with the collection bin. A motor rotates the rotary brush, and a power source supplies power to the motor. A first suction source draws air and debris through the debris intake. A second suction source draws air from the collection bin to create a negative pressure in the collection bin to move the debris drawn through the debris intake by the first suction source into the collection bin in response to the negative pressure in the collection bin created by the second suction source. 
     Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  a perspective view of a floor cleaning machine according to one embodiment of the invention. 
         FIG. 2  is a cross-sectional view of the floor cleaning machine of  FIG. 1 , with portions of a housing of the floor cleaning machine hidden. 
         FIG. 3  is a top view of the floor cleaning machine of  FIG. 2 . 
         FIG. 4  illustrates a bristle agitation projection of the floor cleaning machine of  FIG. 1 . 
         FIG. 5  is a perspective view of an underside of the floor cleaning machine of  FIG. 1 . 
         FIG. 6  illustrates a collection bin of the floor cleaning machine of  FIG. 1 . 
         FIGS. 7A-7E  illustrate removal and emptying of the collection bin of  FIG. 6 . 
         FIGS. 8A-8C  illustrate movement of a handle of the floor cleaning machine of  FIG. 1  between a deployed position and a storage position. 
         FIG. 9  illustrates the handle of the floor cleaning machine of  FIG. 1  locked in the storage position for transport. 
         FIG. 10  is a top view of the floor cleaning machine of  FIG. 1  configured for use with a battery. 
         FIG. 11  is a top view of the floor cleaning machine of  FIG. 1  configured for use with two batteries. 
         FIG. 12  illustrates cooling configuration for the battery of the floor cleaning machine of  FIG. 10 . 
         FIG. 13  is a perspective view of a floor cleaning machine according to another embodiment of the invention. 
         FIG. 14  is a cross-sectional view of the floor cleaning machine of  FIG. 13 . 
     
    
    
     DETAILED DESCRIPTION 
     Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. 
       FIG. 1  illustrates a floor cleaning machine  10  or floor sweeper according to an embodiment of the invention. The machine includes a housing  14  having a front end  18 , a rear end  22 , a handle  26  pivotally coupled to the housing  14  proximate the rear end, and first and second rotary brushes  30   a,    30   b  coupled to the housing  14  proximate the front end  18 . A pair of ground engaging wheels  34  are coupled to the housing  14  proximate the rear end  22  to facilitate moving the machine  10  along a surface to be cleaned (see surface  36  in  FIG. 2 ). 
     Each of the brushes  30   a,    30   b  is rotatable about a brush axis  38  and includes a hub  42  ( FIG. 2 ) and a plurality of bristles  46  extending outward from the hub  42 . The bristles  46  extend from the hub at a downward angle such that the brushes  30   a,    30   b  are generally bowl-shaped. The brushes  30   a,    30   b  are configured to rotate in opposite directions to convey dirt and debris generally inward, toward a longitudinal axis  50  of the machine  10  that extends through the center of the housing  14  and through the front and rear ends  18 ,  22 , and rearward, toward an inlet  54  in the front end  18  of the housing  14  ( FIG. 1 ). For example, the second rotary brush  30   b  on the right hand side of the machine  10  rotates about its brush axis  38  in direction  58 , and the first rotary brush  30   a  on the left hand side of the machine  10  rotates about its brush axis  38  in direction  62 . The brush axes  38  may be oriented vertically (i.e. perpendicular to the surface being cleaned  36 ). In other embodiments, the brush axes  38  may be oblique with respect to the surface being cleaned  36 . For example, the brush axes  38  of  FIG. 2  are inclined forward with respect to the surface being cleaned  36 . In some embodiments, the orientation of the brush axes  38  may be adjustable by a user of the machine  10 . In some embodiments, the height of each of the brushes  30   a,    30   b  may be adjustable. 
     With reference to  FIG. 2 , the machine  10  further includes a brushroll  66  rotatably supported by the housing  14  at a position rearward of the brushes  30   a,    30   b.  The brushroll  66  defines a rotational axis  70  that is generally transverse to the longitudinal axis  50  of the housing  14 . The brushroll  66  is rotatable in direction  74  to sweep dust and debris upward and rearward into a collection bin  78  located within the housing  14  behind the brushroll  66 . The brushroll  66  and the rotary brushes  30   a,    30   b  are driven by a drive assembly  82  that includes at least one electric motor  84 . In the illustrated embodiment, the brushroll  66  can be driven at a maximum rotational speed greater than 440 RPM. For example, in some embodiments, the brushroll  66  can be driven at a maximum rotational speed of 700 RPM. The high brushroll speed advantageously removes more dust and debris from the surface being cleaned than is possible at lower speeds. 
     The motor  84  of the drive assembly  82  may be any type of electric motor but is preferably a DC electric motor, such as a brushed DC motor or a brushless DC motor. The motor  84  can be coupled to the brushroll  66  and the rotary brushes  30   a,    30   b  via one or more belts, pulleys, gears, and the like. In some embodiments, the drive assembly  82  may include multiple motors. For example, in one embodiment (not shown), the drive assembly  82  includes a first motor coupled to the brushroll  66  and a second motor coupled to the rotary brushes  30   a,    30   b.  This allows the brushroll  66  and the rotary brushes  30   a,    30   b  to be controlled independently. In another embodiment (not shown), the drive assembly  82  includes a first motor coupled to the brushroll  66 , a second motor coupled to one rotary brush  30   a,  and a third motor coupled to the other rotary brush  30   b.  This allows the brushroll  66  and each of the rotary brushes  30   a,    30   b  to be controlled independently. In some embodiments, the motors may directly drive the rotary brushes  30   a,    30   b  and/or the brushroll  66 . 
     In some embodiments, the brushroll  66  and the rotary brushes  30   a,    30   b  may also be drivably coupled to the wheels  34 . For example, the machine  10  may be operable in a manual or unpowered mode in which the brushroll  66  and the rotary brushes  30   a,    30   b  are driven in response to rotation of the wheels  34 , as a user pushes the machine  10  along a surface. In some embodiments, the rotary brushes  30   a,    30   b  may be drivably coupled to other ground-engaging wheels, such as castors (not shown) extending downward from the respective hubs  42 . 
     Referring to  FIG. 2 , the illustrated machine  10  includes a suction source  86  that generates a suction airflow at a first suction zone  90  and a second suction zone  94  ( FIG. 2 ). The first suction zone  90  is located proximate a leading edge of the brushroll  66  and generally between the brushroll  66  and the rotary brushes  30   a,    30   b.  The second suction zone  94  is located in the collection bin  78  to produce negative pressure within the collection bin  78 . The suction source  86  is fluidly coupled to the first suction zone  90  via a first flow path  102 , and the suction source  86  is fluidly coupled to the second suction zone  94  via a second flow path  106 . The first flow path  102  and the second flow path  106  each extend through a filter  110  (e.g., a pleated filter), located between the suction zones  90 ,  94  and the suction source  86 . In the illustrated embodiment, the filter  110  is located above the collection bin  78 ; however, the filter can be located elsewhere. In some embodiments, the suction source  86  can generate a maximum combined airflow rate along the first flow path  102  and the second flow path  106  between about 200 CFM and about 500 CFM. 
     Referring to  FIG. 3 , in the illustrated embodiment, the suction source  86  includes a first vacuum motor  114  configured to generate airflow along the first flow path  102  and a second vacuum motor  118  configured to generate airflow along the second flow path  106 . The vacuum motors may  114 ,  118  be controlled to independently vary the airflow rate along the first flow path  102  and the second flow path  106 . In other embodiments, the suction source  86  may include a single vacuum motor configured to generate airflow along both the first flow path  102  and the second flow path  106 . In such embodiments, one or more valves or dampers may be provided in one or both the first flow path  102  and the second flow path  106  to independently vary the airflow rate along the first flow path  102  and the second flow path  106 . In some embodiments, the suction source  86  may not include a vacuum motor but instead may include one or more fans driven by the drive assembly  82 . 
     With reference to  FIG. 5 , the first flow path  102  includes first and second debris intake nozzles  122  that are positioned in the first suction zone  90 . The intake nozzles  122  are positioned forward of the brushroll  66  and are spaced from one another in a direction parallel to the rotational axis  70  of the brushroll  66 . The intake nozzles  122  are preferably located just above the bristles  46  of the rotary brushes  30   a,    30   b  so as to intake dust shed by the rotary brushes  30   a,    30   b.    
     As shown in  FIGS. 2 and 4 , projections  126  are provided in the travel path of the bristles  46  to engage and agitate the bristles  46  as they pass near the intake nozzles  122  in the first suction zone  90 . In other embodiments, the first flow path  102  may include only a single intake nozzle  122  that may extend along the width of the housing  14 , or more than two intake nozzles  122  may be used. 
     Referring to  FIG. 6 , the collection bin  78  in the illustrated embodiment includes an upper wall  130 , a rear wall  134 , a front wall  138  generally opposite the rear wall  134 , and an entry opening  142  in front wall. The upper wall  130  is angled upward at an oblique angle  146  such that a cross-sectional area of the collection bin  78  increases in a direction from the front wall  138  toward the rear wall  134 . The angled upper wall  130  provides clearance for debris that is propelled by the brushroll  66  to pass into the collection bin  78  along an arcuate or generally parabolic trajectory  150 . This advantageously reduces the likelihood that debris entering the collection bin  78  will jam together near the entry opening  142 . In the illustrated embodiment, a comb  154  extends from the entry opening  142  into engagement with the rear side (i.e. the trailing side) of the brushroll  66 . The comb  154  thus spans any gap between the front wall  138  of the collection bin  78  and the brushroll  66  to inhibit debris from accumulating between the brushroll  66  and the front wall  138 . The comb  154  also engages the brushroll  66  as it rotates and may thus dislodge debris from the brushroll  66 . The comb  154  is made of metal in some embodiments for strength and durability. 
     With reference to  FIGS. 7A-E , the illustrated collection bin  78  includes a U-shaped first handle  158  pivotally coupled to the front of the collection bin  78  and a second handle  162  formed in the rear of the collection bin  78 . To remove the collection bin  78  from the housing  14 , a user pivots the first handle  158  up ( FIG. 7A ), then lifts up on the first and second handles  158 ,  162  simultaneously to free the collection bin  78  from the housing  14  ( FIG. 7B ). With the collection bin  78  free from the housing  14 , the user can allow the weight of the collection bin  78  to pivot the collection bin  78  downward about the first handle  158  into a carrying position ( FIGS. 7C and 7D ). In the carrying position, the entry opening  142  of the collection bin  78  is oriented upward toward the first handle  158  so that debris is maintained in the collection bin  78  under the influence of gravity. The user can then empty the collection bin  78  as illustrated in  FIG. 7E . After emptying the collection bin  78 , the user can re-attach the collection bin  78  to the housing  14  by reversing the previous steps. In some embodiments, the collection bin  78  includes one or more transparent regions to permit a user to determine when the collection bin  78  should be emptied. 
     With reference to  FIGS. 8A-C , in the illustrated embodiment, the handle  26  includes a first portion  166  pivotally coupled to the housing  14  and a second portion  170  that can telescope into and out of the first portion  166  to vary an overall length of the handle  26 . The handle  26  is movable between a deployed position ( FIG. 8A ), in which the second portion  170  is fully extended from the first portion  166 , and the handle  26  extends upward and rearward from the housing  14 , and a storage position ( FIG. 8C ) in which the second portion  170  is fully inserted into the first portion  166  and the handle  26  is pivoted downward so as to overlie (i.e. extend along the top surface of) the housing  14 . In some embodiments, the handle  26  can be locked in the storage position, allowing the machine  10  to be transported upright on the wheels  34  ( FIG. 9 ). In some embodiments, controls (including, for example, one or more switches, buttons, dials, and the like) may be provided on the second portion  170  of the handle  26  for controlling operation of the machine  10 . For example, the user may manipulate the controls to turn the suction source  86  on and off, vary the airflow rate along the first flow path  102  and the second flow path  106 , turn the brushroll  66  and the brushes  30   a,    30   b  on and off, and vary the speed of the brushroll  66  and the brushes  30   a,    30   b  ( FIG. 2 ). 
     Referring to  FIG. 10 , the illustrated machine  10  further includes a battery  200  configured to provide power to the drive assembly  82  and the suction source  86 . In some embodiments, the machine  10  is configured to draw a maximum power from the battery  200  during operation of less than 500 Watts. The battery  200  is removably coupled to a battery receptacle  204 , which, in the illustrated embodiment is located on top of the housing  14  and centered along the axis  50 . Alternatively, the battery  200  and receptacle  204  can be located elsewhere. The illustrated battery  200  is a power tool battery pack with a plurality of rechargeable battery cells (e.g., lithium-based battery cells; not shown) providing the battery  200  with a nominal output voltage of about 18V. In other embodiments, the battery  200  can have a different nominal voltage, such as, for example, 12V, 36V, or 40V. In another embodiment illustrated in  FIG. 11 , the machine  10  includes two batteries  200  disposed in adjacent battery receptacles  204 . In such an embodiment, the batteries  200  may be connected in series or in parallel. In other embodiments, the machine  10  may include more than two batteries  200 . Alternatively, the machine  10  may be configured to receive power from a wall outlet or other remote power source. With reference to  FIG. 12 , in some embodiments, at least a portion of the air flowing along the first flow path  102  and/or the second flow path  106  may be directed to cool the battery  200  (or batteries  200 ). For example, the suction source  86  may be configured to discharge air over the battery  200 . 
     With reference to  FIG. 2 , in operation, a user grasps the handle  26  and pushes the machine  10  along a surface to be cleaned. The battery  200  powers the drive assembly  82 , which drives the rotary brushes  30   a,    30   b  and the brushroll  66 . The rotary brushes  30   a,    30   b  sweep dust and debris toward the inlet  54  ( FIG. 1 ). After entering the housing  14 , the dust and debris is swept up and rearward into the collection bin  78  by the brushroll  66  ( FIG. 6 ). The angled upper surface  130  of the collection bin  78  allows the dust and debris to enter the collection bin  78  along an arcuate path  150  to avoid debris build up at the entry opening  142 . Dust and debris that may cling to the bristles  46  of the brushes  30   a,    30   b  is agitated off of the bristles  46  by the projections  126  ( FIGS. 2 and 5 ) and can then be entrained in the first air flow path  102  via the inlet nozzles  122  or swept up by the brushroll  66 . Dust and debris that may cling to the brushroll  66  is agitated off of the brushroll  66  by the comb  154 . The negative pressure in the collection bin  78  due to the second suction zone  94  helps draw dust and debris into the collection bin  78 . The user may manipulate the controls to turn the suction source  86  on and off, independently vary the airflow rate along the first flow path  102  and the second flow path  106 , turn the brushroll  66  and the brushes  30   a,    30   b  on and off, and vary the speed of the brushroll  66  and the brushes  30   a,    30   b  to optimize cleaning performance. 
     In some embodiments, the machine  10  may also be used in a manual or unpowered mode (e.g., if the battery  200  is depleted or removed from the machine  10 ). In the manual mode, the brushroll  66  and the rotary brushes  30   a,    30   b  are driven in response to rotation of the wheels  34  or other ground-engaging features as the user pushes the machine  10  along the surface to be cleaned. In the manual mode, the drive assembly  82  may be disconnected from the brushroll  66  and the brushes  30   a,    30   b.    
       FIGS. 13 and 14  illustrate a floor cleaning machine  1010  according to another embodiment. The floor cleaning machine  1010  is similar to the floor cleaning machine  10  described above with reference to  FIGS. 1-12  but includes two brushrolls  1066   a,    1066   b,  each rotating in opposite directions. In addition, the collection bin  1078  is disposed between the wheels  1034  and has a cylindrical shape defining a longitudinal axis  1208  that is coaxial with the rotational axis of the wheels  1034 . 
     Although the invention has been described in detail with reference to certain preferred embodiments, variations and modifications exist within the scope and spirit of one or more independent aspects of the invention as described.