Patent Publication Number: US-8533905-B1

Title: Vacuum accessory tool

Description:
BACKGROUND OF THE INVENTION 
     Household pets, such as dogs and cats, tend to shed hair, which collects on carpets, furniture, and other areas of the home. A common complaint of pet owners is the seemingly never-ending battle to remove the pet hair. Pet hair and other similar debris can be relatively small and difficult to collect, even with conventional vacuum cleaners. Further, when vacuum cleaners having rotating or otherwise moving parts, such as rotatable agitators and air turbines, in the suction path are used to remove pet hair and other similar debris, the pet hair can collect at the moving parts, thereby impeding the operation and effectiveness of the vacuum cleaner. 
     U.S. Pat. No. 6,711,777 to Frederick et al. discloses a turbine powered vacuum cleaner tool wherein a nozzle body encloses an agitator located adjacent an elongated suction inlet opening. A turbine rotor is rotatably connected to the nozzle body and operatively connected to the agitator so that airflow generated by a remote suction source flows through the nozzle body and rotates the agitator. 
     U.S. Pat. No. 4,042,995 to Varon discloses a brush for removing animal hair from carpeting and upholstery comprising a plurality of flexible bristles composed of polymeric materials that create an electrostatic charge to attract the animal hair to the bristles. 
     U.S. Pat. No. 3,574,885 to Jones discloses a brush having a base member, a plurality of flexible plastic bristles mounted to the base member and a tubular adapter for connection with a vacuum cleaner to remove loose hair dislodged while brushing an animal. In an alternate embodiment, the brush comprises a mitt secured to a flexible base member to receive the hand of the operator. 
     German Patent Application Publication No. 2,100,465 to Schwab discloses a sweeper with a horizontal brush driven by the rotation of ground engaging wheels. Bristle pads are arranged on both sides of the brush and have bristles directed toward the rotating horizontal brush. 
     U.S. Patent Application Publication No. 2002/0170140 to Diaz et al, now abandoned, discloses a vacuum cleaner adapter comprising a bristle wheel comprising protruding bristles for removing hair and animal fur from rugs and carpets. The bristles can be made of natural or synthetic organic, polymeric, elastomeric, or composite materials such as nylon, rubber, or the like. 
     U.S. Pat. No. 5,148,569 to Jailor discloses a debris impeller for a cleaning device comprising impeller segments with a non-cylindrical opening configured to be slipped over a twisted flat wire axle. Each impeller segment comprises a plurality of resilient paddles that extend radially outwardly from a central hub section. 
     U.S. Patent Application Publication No. 2006/0248680 to Heidenga et al. discloses a vacuum accessory tool having a rotating agitator brush with bristles and a separate hair removal element. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the invention, a vacuum accessory tool comprises a nozzle body, a suction nozzle formed by the nozzle body, a suction conduit formed in the nozzle body and adapted to be connected to a suction source remote from the nozzle body for generating a working air flow from the suction nozzle through the nozzle body, and an agitator assembly mounted to the nozzle body and positioned adjacent the suction nozzle. The agitator assembly comprises a dowel mounted within the nozzle body for rotational movement about an axis and an agitating element provided on the dowel and comprising a plurality of resilient blades extending generally axially along and projecting outwardly from the dowel, wherein at least two of the resilient blades have a gap therein extending from a distal end of the blade toward the dowel, and wherein the gap in one of the at least two resilient blades is axially offset from the gap in another of the at least two resilient blades. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a front perspective view of a vacuum accessory tool with a hair removal assembly and an impeller assembly according to one embodiment of the invention. 
         FIG. 2  is a bottom view of the vacuum accessory tool shown in  FIG. 1 . 
         FIG. 3  is an exploded view of the vacuum accessory tool shown in  FIG. 1 . 
         FIG. 4  is a sectional view taken along line  4 - 4  of  FIG. 2 . 
         FIG. 5  is a top view of the vacuum accessory tool of  FIG. 1 , with the top housing removed for clarity. 
         FIG. 6  is a partial cross-sectional view taken along line  6 - 6  of  FIG. 5 . 
         FIG. 7  is a partial cross-sectional view taken along line  7 - 7  of  FIG. 5 . 
         FIG. 8  is a partial cross-sectional view taken along line  8 - 8  of  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION 
     The invention generally relates to vacuum cleaning accessory tools. In one aspect, the invention relates to an accessory tool adapted to remove pet hair from carpet and other fabric surfaces. In another aspect, the invention relates to an accessory tool having an improved agitator assembly comprising an agitating element having a plurality of resilient blades that enhance hair removal and to prevent hair wrapping around the agitator dowel. For purposes of description related to the figures, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the accessory tool as oriented in  FIG. 1  from the perspective of a user behind the accessory tool, which defines the rear of the accessory tool. However, it is to be understood that the invention may assume various alternative orientations, 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 in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise. 
     Referring to the drawings,  FIGS. 1-3  show a vacuum accessory tool  10  having a nozzle body formed by an upper housing  12  and a lower housing  14 . The upper and lower housings  12 ,  14  can be secured together with mechanical fasteners  16 . Alternatively, the upper and lower housings  12 ,  14  can be secured together via a removable retaining ring as described in U.S. Patent Application Publication No. 2006/0248680 to Heidenga et al., which is incorporated herein by reference in its entirety, or by other conventional fastening means such as adhesive, ultrasonic welding, or the like. A suction nozzle  18  is formed at a forward, lower portion of the lower housing  14 . 
     The upper housing  12  further comprises a working air conduit  36  positioned on an end of the nozzle body  10  opposite the suction nozzle  18 . The working air conduit  36  fluidly communicates the suction nozzle  18  with a remote suction source, as is commonly found in an upright or canister vacuum cleaner. The working air conduit  36  is typically connected to the upright or canister vacuum cleaner via a flexible hose. A lower agitator chamber  38  is formed in a forward portion of the lower housing  14  in close proximity to and in fluid communication with the suction nozzle  18 . 
     An agitator assembly  40  having a dowel  48  that supports an agitating element  20  is rotatably mounted within the agitator chamber  38  via bearing assemblies  42 , which are located on the ends of the dowel  48 . Slotted ribs  46  are offset from the inner sidewalls of the agitator chamber  38  and form opposed brush bearing supports  44  that are sized to receive agitator bearing assemblies  42 . The cylindrical dowel  48  includes bearing pins  34  fixed at both ends thereof. The bearing pins  34  are rotatably received within the bearing assemblies  42 , thus permitting the dowel  48  to rotate about an axis X with respect to the agitator chamber  38 . The agitator assembly  40  further comprises an agitator pulley  47  formed on the dowel  48  near of end of the dowel  48 . 
     Referring now to  FIG. 3 , an impeller chamber  50  is formed between the suction nozzle  18  and the working air conduit  36  and receives an air-driven impeller assembly  52 . In the illustrated embodiment, the impeller assembly  52 , which is shown in  FIGS. 3 and 5 , comprises a plurality of arcuate blades  54  that extend radially outwardly from a central hub  55  between two end walls  56 . The sets of the blades  54  are offset from one another so that a blade  54  of one of the sets is positioned between adjacent blades  54  of the other set, as best viewed in  FIG. 5 . Alternatively, the sets of blades can be aligned with each other. 
     The impeller assembly  52  is mounted on an axle  62  that passes through the hub  55  and defines an axis about which the impeller assembly  52  rotates. The axle  62  is received within opposed bearing assemblies  58  that are mounted to bearing supports  60  formed within the impeller chamber  50  and protruding from the upper and lower housings  12 ,  14 . A belt pulley  64  is fixed to one end of the axle  62  and is adapted for cooperative rotation therewith. A drive belt  68  operably connects the belt pulley  64  to the agitator pulley  47 . In operation, when the blades  54  are exposed to a moving air stream, such as that created by the remote suction source, the axle  62  rotates with the blades  54 , and the belt pulley  64  rotates with the axle  62 . Additional details of a suitable impeller assembly  52  for use with the vacuum accessory tool  10  can be found in Heidenga, referenced above. 
     Referring now to  FIG. 3 , the lower housing  14  further comprises a belt compartment  66  formed adjacent the impeller chamber  50  and extending into the agitator chamber  38 . The belt compartment  66  is sized to receive a drive belt  68 , which mechanically couples the belt pulley  64  on the impeller assembly  52  to the agitator pulley  47  on the agitator assembly  40 . The belt  68  is maintained under tension between the belt pulley  64  and the agitator pulley  47  so that rotation of the belt pulley  64  induces rotation of the belt  68  and, thereby, the agitator pulley  47  to rotate the agitator assembly  40 , as is well-known in the vacuum cleaner art. The upper housing  12  forms a cover to mate with the lower housing  14  and enclose the agitator assembly  40 , the impeller assembly  52 , and the belt  68  while also forming an upper surface of a working air path from the suction nozzle  18 , through the agitator chamber  38 , and through the impeller chamber  50  to the working air conduit  36 . 
     Alternatively, instead of being coupled to an impeller assembly  52  that is driven by a remote suction source, the agitator assembly  40  can be operably interconnected with a motor (not shown) provided within the nozzle body  10 . The motor can be coupled with the drive belt  68  for imparting rotational movement to the agitator assembly  40 . 
       FIG. 4  is a cross-sectional view taken along line  4 - 4  of  FIG. 2 . The agitating element  20  comprises primary portion having a plurality of resilient blades  70  extending generally axially along and projecting outwardly from the dowel  48 . The blades  70  include a proximal end attached to a base  72  that wraps around the dowel and a free distal end  74 . As illustrated, three radially spaced blades  70  are provided on the dowel  48 , each of which share a common base  72 . The three successive blades  70  are optionally referred to as “ 70 A”, “ 70 B” and “ 70 C” for purposes of discussion. Alternatively, additional blades  70  can be incorporated onto the dowel  48  or one of the three blades  70  can be removed. The blades  70  can extend along and wrap around the dowel  48  in a non-parallel orientation with respect to the axis X of the dowel  48 ; in the illustrated embodiment, the blades  70  are helical. The blades  70  can be secured to the dowel  48  by various manufacturing techniques, such as overmolding, insert molding, application of an adhesive or mechanical engagement. As illustrated, the blades  70  are secured to the dowel  48  using insert molding; as such, the blades  70  are formed from one continuous piece of material connected by the base  72 , which is made of the same material as the blades  70 . Alternatively, each blade  70  can be provided with a separate base  72  and individually attached to the dowel  48 . 
     The blades  70  can be molded from a flexible thermoplastic elastomer material, such as, but not limited to, a mixture of EPDM (ethylene propylene diene monomer) rubber and polypropylene (i.e. Santoprene™) or silicone. However, other elastomeric materials are contemplated for use in molding the blades  70 , such as, but not limited to, rubber, nitrile rubber, and polyurethane. 
     A plurality of gaps  76  are formed in each blade  70 , and extend from the distal end  74  toward the dowel  48 . As illustrated, the gaps  76  extend from the distal end  74  to the base  72 , although in another embodiment, the gaps  76  may only extend through a portion of the height of the blade  70 . The gaps  76  divide each blade  70  into a plurality of flexible flaps  78  that are arranged in a single row  80  that extends axially along the dowel  48 . 
     The agitating element  20  also comprises an optional secondary portion, having a single elastomeric flap  82  aligned with each blade  70  of the primary portion. As illustrated, the primary and secondary portions are separated by the agitator pulley  47 . Due to the placement of the agitator pulley  47 , extra flaps  82  may be required to “fill-in” the remaining span of the suction nozzle  18 . Like the blades  70 , the flaps  82  can be secured to the dowel  48  by various manufacturing techniques, such as overmolding, insert molding, application of an adhesive or mechanical engagement. As illustrated, the flaps  82  are secured to the dowel  48  using overmolding; as such, the flaps  82  are formed from one continuous piece of material connected by a base  84  made of the same material that wraps around the dowel  48 . 
     Both the gaps  76  in the blades  70  and the nominal thickness “T” of the blades  70  can be relatively small as compared to a width “W” of the flaps  78  (i.e. as compared with the distance between the adjacent gaps  76 ). The width of the gaps  76  in the blades  70  can range from 0.5 mm to 2.0 mm, but can also be adjusted to accommodate various configurations. The nominal thickness “T” ( FIG. 17 ) of each blade  70  is 1.0 mm, although a thickness range from approximately 0.75 mm to 2.0 mm is contemplated. The width “W” of each flap  78  ranges from approximately 5 mm to 20 mm, although narrower or wider flaps  78  are contemplated, depending on the length of the dowel  48 . Further, as illustrated, the width “W” of the flaps  78  may vary; alternatively, each flap  78  can have the same width “W”. The average height “H” of the blades  70  is approximately 10 mm, although different heights “H” are contemplated. In the embodiment shown, the height profile of each blade  70  substantially constant; the height profile appears to taper in  FIG. 4  because the blades  70  are helically oriented. Alternatively, the height profile of the blades  70  can vary between ends of the dowel  48 . Furthermore, the height profile of successive blades  370  can be different. The blades  70  can also be notched to accommodate features within the nozzle body  10 , for example drive belts or other structural features. As illustrated one of the flaps  78  of each blade  70  is provided with a notch  86  for accommodating a rib  87  within the nozzle body  10 . 
     Referring to  FIGS. 6-8 , the flaps  78  in each blade  70  are at least partially juxtaposed so that at least one of the gaps  76  in the blades  70  do not align with at least one of the gaps  76  in at least one of the other successive blades  70 . Referring to  FIG. 6 , which shows a cross-sectional view taken along line  6 - 6  of  FIG. 5 , the section datum intersects one pair of the aligned gaps  76  of blades  70 A and  70 C, and intersects one of the flaps  78  of blade  70 B.  FIG. 7  shows a cross-sectional view taken along line  7 - 7  of  FIG. 5 . This section datum intersects one of the flaps  78  of blade  70 A and one pair of the aligned gaps  76  of blades  70 B and  70 C.  FIG. 8  shows a cross-sectional view taken along line  8 - 8  of  FIG. 5  and intersects one pair of the aligned gaps  76  of blades  70 A and  70 B and intersects one of the flaps  78  of blade  70 C. It can further been seen in  FIG. 5  that each blade pair includes two pairs of aligned gaps  76 . 
     Accordingly, the flaps  78  and gaps  76  of each blade  70  are juxtaposed relative to those of other blades  70  such that the gaps  76  in at least one of the blades  70  are misaligned with the gaps  76  in at least one of the successive blades  70  oriented along a co-planar datum perpendicular to the longitudinal axis of the dowel  48 . A flap  78  of at least one blade  70  is offset to obstruct aligned gaps  76  in the successive blades  70 . Offsetting the gaps  76  has been shown to prevent hair from wrapping around the agitator assembly  40 , which is a commonly-encountered problem in the floor care industry. Hair wrap around the agitator assembly  40  can bind up the agitator bearing assemblies  42  and eventually jam the agitator assembly  40 , preventing free rotation thereof and inhibiting debris pickup. 
     In addition to reducing hair wrap, the plurality of flaps  78  exhibit improved flexibility relative to a single continuous blade  70 , and thus less force and torque are required to deflect the blades  70  and rotate the agitator assembly  40  during use. Furthermore, each flap  78  can deflect independently of an adjacent flap  78  of the same blade  70  to accommodate contoured or otherwise non-uniform cleaning surfaces. Moving contact between the distal end  74  of the blades  70  and the surface forms an electrostatic charge. Accordingly, a significant electrostatic charge develops on the blade  70 , which can thereby attract a large quantity of surface hair and debris, including relatively heavy hair and debris. 
     In operation, a user fluidly connects the vacuum accessory tool  10  to a downstream suction source via a suction hose (not shown) to draw a working airflow through the suction nozzle  18 . A user moves the tool across the surface to be cleaned in a reciprocal motion. The working air flows through the agitator chamber  38 , into the impeller chamber  50  and contacts the impeller blades  54 , causing the impeller  52  to rotate. The impeller axle  62  rotates within the bearing assemblies  58  and the belt pulley  64  rotates cooperatively with the axle  62 . The belt pulley  64  rotates the drive belt  68 , which, in turn, engages the agitator pulley  47  and rotates the dowel  48 . The agitating element  20  attached to the dowel  48  rotates cooperatively therewith and engages the cleaning surface. The juxtaposed flaps  78  of the blades  70  successively contact the cleaning surface. The blades  70  agitate the surface and facilitate ingestion of dirt, debris, and hair into the suction nozzle  18 , thereby entraining it in the working airflow. The gaps  76  formed in the blades  70  permit facile deflection of the flaps  78 , thereby reducing the drive torque required to rotate the dowel  48  when the agitating element  20  is in contact with the cleaning surface. The gaps  76  in successive blades  70  are purposefully misaligned to prevent hair from wrapping around the dowel  48  and subsequently jamming agitator bearing assemblies  42  or enshrouding the agitating element  20 . Accordingly, at least one flap  78  interrupts successive aligned gaps  76  of successive blades  70 . Upon entrainment of debris into the working air path, the debris passes through the agitator chamber  38 , into the impeller chamber  50  and around the impeller blades  54  and exits the vacuum accessory tool  10  through the conduit  36 , whereupon the working air passes through the suction hose and into a downstream suction source, where debris can be separated from the working air and collected in a dirt cup or filter bag as is commonly known in the art. 
     Results of a laboratory hair wrap test conducted under controlled laboratory conditions reveals hair wrap performance of various agitator configurations as described hereinafter. Three accessory tools having different agitator assemblies were tested, including: “sample 1” having the aforementioned blade and offset gap configuration shown in the embodiment of  FIGS. 1-8 ; “sample 2” having blades with aligned gaps; and “sample 3”, a control sample comprising a conventional brush dowel with a plurality of conventional bristle tufts commonly known in the art. A one gram [1 g] quantity of human hair ranging in length from six (6) to eight (8) inches was introduced to the accessory tool for ingestion through the suction nozzle. Upon ingestion of the hair, each agitator assembly was removed from the agitator chamber and the quantity of hair remaining wrapped around the dowel was weighed. Three (3) trials were performed for each of the three (3) sample agitator assembly configurations. The average results showed that the “sample 2” agitator assembly with blades having aligned gaps retained 20% less hair than the control “sample 3” with conventional bristle-tufted brush dowel. However, the “sample 1” agitator assembly with blades having offset gaps surpassed the performance of “sample 2” and retained 48% less hair than the control “sample 3” comprising the conventional bristle-tufted brush dowel. 
     
       
         
           
               
               
               
             
               
                   
               
               
                   
                 Hair Remaining on 
                 % Improvement  
               
               
                 Sample Description 
                 Agitator [g] 
                 over control Sample 3 
               
               
                   
               
             
            
               
                 Sample 1 
                 0.26 g 
                 48% 
               
               
                 (blades with offset 
                   
                   
               
               
                 gaps) 
                   
                   
               
               
                 Sample 2 
                 0.40 g 
                 20% 
               
               
                 (blades with aligned 
                   
                   
               
               
                 gaps) 
                   
                   
               
               
                 Sample 3 
                 0.50 g 
                 — 
               
               
                 (control sample with 
                   
                   
               
               
                 bristle tufts) 
               
               
                   
               
            
           
         
       
     
     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 modification are possible within the scope of the foregoing description and drawings without departing from the scope of the invention, which is described in the appended claims.