Patent Publication Number: US-2006016167-A1

Title: Lawn vacuum

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      This application claims the benefit of U.S. Provisional Patent Application No. 60/589,271, filed Jul. 20, 2004. 
    
    
     BACKGROUND OF THE INVENTION  
      The present invention relates generally to devices used to collect debris and, more particularly, to a lawn vacuum used to collect debris, such as grass and leaves.  
      Vacuum devices for collecting debris such as grass clippings and leaves are known in the art. One conventional lawn vacuum comprises a collector which can be mounted on the rear of a riding mower. Such systems generally include a blower or vacuum system that draws clippings from a discharge port in the mower deck to the collector. Other collection systems include push mowers with bags mounted at the rear or side of the mower. Such systems typically utilize the driving force of the lawn mower blades to propel the grass cuttings and debris into the bag.  
      Lawn vacuums without mowers have also been developed. Such vacuums often include a nozzle at the front end operatively associated with a motor driven impeller and a collection bag. A deficiency of the prior lawn vacuums becomes evident when the user attempts to vacuum over an obstacle on the surface of the ground. The nozzle height of some lawn vacuums is rigidly set at a certain height, forcing a user to manually tilt the lawn vacuum upwardly to overcome the obstacle if the obstacle were to extend above the nozzle height. Some nozzles are pivotably mounted and include wheels to ride over large obstacles. However, the wheels are mounted behind the nozzle creating problems in that the nozzle does not react quickly enough to debris or large obstacles.  
      Collection assemblies within lawn mowers that utilize cyclonic motion are also known. Lawn mowers that utilize cyclonic motion within the collection assembly are used in conjunction with a solid housing. The solid housings typically include openings at or near the top of the assembly for air to escape. This results in lack of downward air circulation within the assembly and debris generally does not fill the assembly to its maximum capacity. Thus, the solid housing hinders downward airflow and premature replacement of the collection assembly results. In addition, the outlet is located at a chest or head height of a user where air or other debris flows out of the outlet. Such an outlet height irritating and potentially dangerous to a user and bystanders.  
      A need exists, therefore, for a lawn vacuum which easily traverses large debris without user intervention. In addition, a need exists for a collection assembly capable of efficient collection of debris that deflects debris into a collection area away from a user and directs outlet air and debris away from the user and any bystanders.  
     BRIEF SUMMARY OF THE INVENTION  
      Briefly stated, a preferred embodiment of the present invention is directed to a lawn vacuum for removing debris from a ground surface and storing the debris for disposal. The lawn vacuum includes a frame, a nozzle defining an inlet mounted to the frame and an impeller in communication with the nozzle through a tube to create a vacuum pressure at the inlet for drawing the debris into the nozzle. A discharge adapter includes a first end and a discharge end. The first end is mounted to an outlet end of the impeller for carrying the debris away from the impeller. A bag assembly includes a bag, a sleeve and a lid. The discharge end of the discharge adapter is mounted to dispense debris from the impeller into a chamber defined by the bag assembly. The sleeve is generally air impervious and has a generally cylindrical shape. The sleeve includes a first mouth and a second mouth and the bag includes an open top end and a closed bottom end. The bag is mounted at its top end to the first mouth of the sleeve such that the bag is at least partially encompassed by the sleeve such that the sleeve generally guides air entering the bag assembly toward the second mouth.  
      In another aspect, a preferred embodiment of the present invention is directed to a lawn vacuum for removing debris from a ground surface and storing the debris for disposal. The lawn vacuum includes a frame, a nozzle mounted to the frame and defining an inlet and an impeller mounted to the frame for creating a vacuum pressure at the inlet to draw debris into the inlet. A bag assembly includes a lid and a container in communication with the impeller. The lid includes a top wall, a generally cylindrical flange and an inner cylinder. The flange and inner cylinder define a debris deflection area for deflecting debris drawn into the container by the impeller.  
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
      The foregoing summary, as well as the following detailed description of preferred embodiment of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings an embodiment which is presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.  
      In the drawings:  
       FIG. 1  is a is a side elevation view of a lawn vacuum in accordance with a preferred embodiment of the present invention;  
       FIG. 2  is a front elevation view of the lawn vacuum of  FIG. 1 ;  
       FIG. 3  is a top plan view of the lawn vacuum of  FIG. 1 ;  
       FIG. 4  is a partial cross-sectional view of the lawn vacuum of  FIG. 3  taken along line  4 - 4  of  FIG. 3 ;  
       FIG. 5  is an enlarged cross-sectional view of the lawn vacuum bag assembly of  FIG. 4  taken along line  5 - 5  of  FIG. 4 ;  
       FIG. 6  is a side elevation view of the lawn vacuum bag assembly of  FIG. 5  taken along line  6 - 6  of  FIG. 5 ;  
       FIG. 7  is a cross-sectional side view of the lawn vacuum bag assembly of  FIG. 5  taken along line  7 - 7  of  FIG. 5 ;  
       FIG. 8  is a fragmentary view of a channel of the collection bag assembly of  FIG. 7 ; and  
       FIG. 9  is a greatly enlarged cross-sectional view of a buckle portion of the collection bag assembly of  FIG. 7  taken along line  9 - 9  of  FIG. 7 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      Certain terminology is used in the following description for convenience only and is not limiting. The words “right”, “left”, “upper” and “lower” designate directions in the drawings to which reference is made. The words “inwardly” and “outwardly” refer to directions toward and away from, respectively, the geometric center of the lawn vacuum and designated parts thereof. The word “a” is defined to mean “at least one”. The terminology includes the words above specifically mentioned, derivatives thereof, and words of similar import.  
      Referring to the drawings in detail, wherein like numerals indicate like elements throughout the figures, there is shown in  FIGS. 1-4 , a preferred lawn vacuum, generally designated  10 , which is used to gather or remove debris such as grass and leaves from a ground surface  80  and storing the debris for disposal. The lawn vacuum  10  includes a frame  12  supported by wheels  14   a ,  14   b ,  16   a ,  16   b . The frame  12  supports a collection bag assembly  20  and an engine  18  that is connected to an impeller  19 . Furthermore, a nozzle  28  extends from a flexible tube  26  that is operatively connected to the impeller  19 . The engine  18 , impeller  19 , nozzle  28  and wheels  14   a ,  14   b ,  16   a ,  16   b  are preferably mounted to the frame  12 .  
      Referring to  FIGS. 1-4 , the frame  12  supports a front axle  32   a  and a rear axle  32   b  which rotatably support the two front wheels  14   a ,  14   b  and two rear wheels  16   a ,  16   b , respectively. In the preferred embodiment, the frame  12  is constructed from a series of interconnected tubes which form a double L-shape and is preferably made of a light weight high strength material, such as steel or aluminum. The frame  12  includes a handle  78  extending, across the rear of the lawn vacuum  10 . From this disclosure, one of ordinary skill in the art would recognize that the frame  12  could be made from other materials, such as plastics or composite materials. Furthermore, one of ordinary skill in the art would recognize that the frame  12  could be one continuous piece and the shape of the frame  12  could be constructed in any manner so long as it could support the necessary components and withstand the normal operating conditions of the lawn vacuum  10 , as is described below.  
      The engine  18  is preferably secured to a platform or lower portion  54  of the frame  12 . A throttle control  38  is located on the handle  78  on an upper portion  56  of the frame  12  and controls the speed of the engine  18  via a cable  40 . In the preferred embodiment, the engine  18  is a gasoline engine. Engines for operating lawn vacuums are well known to those of ordinary skill in the art. Accordingly, further description of the engine  18  is omitted for purposes of convenience only and is not limiting.  
      Referring to  FIGS. 1 and 4 , the impeller  19  is attached to and powered by the engine  18  and is enclosed by a housing assembly  24 . The housing assembly  24  is operably connected to a discharge adapter  22  on one end and a tube  26  on an opposite end. The tube  26  is preferably constructed with a flexible material, such as soft plastic such that the nozzle  28  is able to move relative to the frame  12 , as will be described in greater detail below. In the preferred embodiment, the housing assembly  24 , impeller  19  and discharge adapter  22  are constructed of a sturdy material, such as steel or aluminum. One of ordinary skill in the art would recognize that other materials, such as plastics or composite materials, could be substituted without departing from the spirit and scope of the invention.  
      The nozzle  28  is operably connected to the distal end of the flexible tube  26  and extends down to the ground surface  80 . The nozzle  28  defines an inlet  29  that is preferably facing the ground surface  80  in the working position and opens into a hollow of the flexible tube  26 . The nozzle  28  preferably has curved ends  28   a ,  28   b  and is pivotally supported by a front bracket  30  that pivots about the front axle  32   a . In the preferred embodiment, the front bracket  30  is pivotally mounted to the front axle  32   a  between the two front wheels  14   a ,  14   b  and is mounted to an inner surface of the nozzle  28 . The front bracket  30  is preferably connected to a nozzle height control  34  located on the handle  78 . The nozzle height control  34  preferably permits a user to modify the height of the nozzle  28  relative to the ground surface  80  by manipulating a cable  36 . The flexible tube  26  and front bracket  30  permit the nozzle  28  to pivot about the front axle  32   a  for modification of the height of the nozzle  28  and inlet  29  relative to the ground surface  80 . It may be advantageous to modify the height of the nozzle  28  relative to the ground surface  80  depending upon the amount of size of debris being encountered by the lawn vacuum  10  or the roughness of the ground surface  80  itself, as will be understood by one having ordinary skill in the art. For example, if the lawn vacuum  10  is going to encounter a relatively tall piece of debris, the user may raise the nozzle  28  and inlet  29  relative to the ground surface  80  such that the debris moves under the inlet  29  as the lawn vacuum  10  travels toward and over the debris.  
      The impeller  19  is in communication with the nozzle  28  through the tube  26  such that a vacuum pressure may be created at the inlet  29  for drawing debris into the nozzle. Accordingly, when the nozzle  28  and inlet  29  are positioned over a piece of debris, the vacuum pressure at the inlet  29  draws the debris into the inlet  29  and into the tube  26 .  
      The preferred nozzle  28  may include nozzle wheels  27  (shown in phantom) rotatably attached to the lateral ends of the nozzle  28  or the nozzle wheels  27  may be built into the ends of the nozzle  28  such that only a bottom portion of the wheels  27  is visible in a plan view. Using wheels  27  on the front end of the nozzle  28  allows the nozzle  28  to navigate over debris in the path of the lawn vacuum  10 . One having ordinary skill in the art will realize that the nozzle wheels  27  are not required for the operation of the lawn vacuum  10  and may be completely eliminated from the device, without severely impacting the overall operation of the lawn vacuum  10 .  
      Referring to  FIGS. 1-3 , the discharge adapter  22  includes a first end  22   a  and a discharge end  22   b . The first end  22   a  is mounted to an outlet end  19   b  of the impeller  19  for carrying debris away from the impeller  19 . The discharge adapter  22  is preferably constructed of a generally rigid structural material that is able to withstand the normal operating conditions of the lawn vacuum  10 . For example, the discharge adapter  22  may be constructed of an aluminum, steel, polymeric or composite material that is able to take on the general shape and size of the discharge adapter  22 . In addition, the first end  22   a  is preferably adaptable to the outlet end  19   b  of the impeller  19  such that debris driven by the impeller  19  exiting the outlet end  19   b  is received into the first end  22   a.    
      Referring to  FIGS. 1, 3  and  4 , the frame upper portion  56  supports the collection bag assembly  20 , which includes a lid  42  that is preferably rigidly attached to the frame upper portion  56 , a debris bag  44  and a sleeve  46 . The discharge end  22   b  of the discharge adapter  22  is mounted to the bag assembly  20  to dispense the debris into a storage chamber  82  defined by the bag assembly  20 . The sleeve  46  is preferably constructed of an air impervious material, has a generally cylindrical shape and includes a first mouth  46   a  and a second mouth  46   b . In the preferred embodiment, the sleeve  46  is constructed of a polymeric material and, more specifically, a synthetic rubber material. The synthetic rubber material is preferred for the construction of the sleeve  46  due to its toughness, formability and relatively light weight. However, one having ordinary skill in the art will realize that the sleeve is not limited to being constructed of a polymeric material or to the synthetic rubber material and may be constructed of nearly any material that is able to take on the general shape of the sleeve and withstand the normal operating conditions of the lawn vacuum  10 .  
      The lid  42  preferably has a substantially circular or disc-like shape and is preferably constructed of a solid material. The lid  42  preferably includes a top wall  42   a , an inner cylinder  50  that extends generally perpendicularly from the top wall  42   a  toward the bag  44  in a working configuration and a generally cylindrical flange  42   b  that extends generally perpendicularly from the top wall  42   a  toward the bag  44  in the working configuration. The inner cylinder  50  and cylindrical flange  42   b  define an annular debris deflection area  51  into which debris flows as the debris exits the discharge end  22   b  of the discharge adapter  22 . In the preferred embodiment, the lid  42  and the inner cylinder  50  are constructed of a generally rigid polymeric material and, specifically, a plastic material. One of ordinary skill in the art would recognize that other rigid materials could be substituted for the construction of the lid  42 , such as steel or composite materials. Furthermore, one of ordinary skill in the art would recognize that the lid  42  may be constructed in other various shapes. In the preferred embodiment, as the debris and air enters the annular debris deflection area  51 , the debris and air are deflected by surfaces of the inner cylinder  50  and flange  42   b  to rotate around the deflection area  51  and downwardly toward the bottom of the bag assembly  20 , as is described in greater detail below.  
      Referring to  FIGS. 5-7 , the debris bag  44  is shaped similar to a tea bag (see  FIG. 7 ) in the preferred embodiment and includes a top portion  44   a  and a bottom portion  44   b  which are mechanically secured by stitching at an intersection line  76 . In the preferred embodiment, the top portion  44   a  is constructed of a mesh fabric and the bottom portion  44   b  is constructed of an air impervious material, most preferably, ballistic nylon. The mesh fabric is preferably made from polyester or polypropylene. The debris bag  44  is open at a top end  49   a  of the top portion  44   a  and closed at a bottom end  49   b  of the bottom portion  44   b . One of ordinary skill in the art will recognize that the debris bag  44  may take on nearly any shape and utilize numerous additional materials as long as the bag  44  is able to withstand the normal operating conditions of the lawn vacuum  10  and perform the normal functions of the bag  44  during operation of the lawn vacuum  10 . The bag  44  is preferably mounted at its top end  49   a  to the first mouth  46   a  of the sleeve  46  such that the bag  44  is at least partially encompassed by the sleeve  46  and such that the sleeve  46  generally guides air entering the bag assembly  20  toward the second mouth  46   b . In the preferred embodiment, based upon the configuration of the bag assembly  20  and the orientation of the discharge end  22   b  relative to the deflection area  51 , the air and debris are urged into the bag  44  in a generally downward circular path toward the second mouth  46   b . The debris is generally captured in the chamber  82 , which is defined by the bag  44 , and the air exits the bag assembly  20  through the second mouth  46   b , which is preferably close to the ground surface  80 , resulting in the forced air being directed away from a head and chest area of a user and any bystanders.  
      Referring to  FIGS. 7 and 8 , the top portion  44   a  is preferably attached to the lid  42  and is substantially surrounded at its sides by the air impervious sleeve  46 . In the preferred embodiment, the sleeve  46  is cylindrical in shape and is constructed of synthetic rubber. One of ordinary skill in the art would recognize that the sleeve  46  could take on other shapes and alternate materials could be substituted. The sleeve  46  is preferably hollow and open on both ends prior to attachment to the debris bag  44 . The top end  49   a  of the debris bag  44  is preferably layered or overlaps with the first mouth  46   a  of the sleeve  46 . The first mouth  46   a  and top end  49   a  are then folded inwardly onto themselves to form a channel  72 . In the preferred embodiment, the first mouth  46   a  and top end  49   a  are stitched or sewed together to form a seam  70 . One of ordinary skill in the art would recognize that other forms of mechanical attachments such as riveting, adhesively fastening, bolting or clipping could be used without departing from the spirit and scope of the invention.  
      Referring to  FIGS. 5-9 , the debris bag  44  and the sleeve  46  are preferably, mechanically secured to the lid  42 . A semi-rigid band  68  having a first end  68   a  and a second end  68   b  is located within the channel  72  and snugly fits over the outer circumference of the lid  42 . The band  68  is substantially greater in length than the circumference of the lid  42  such that the band  68  overlaps at or near a quick connect device  66 . A strap  64  having a first end  64   a  and a second end  64   b  is secured on top of the band  68  and within the channel  72 . In the preferred embodiment, the band  68  is constructed of nylon and the strap  64  is constructed of polypropylene webbing. One with ordinary skill in the art would recognize that other materials that are able to withstand the stresses encountered by the band  68  and strap  64  could be substituted. In addition, one having ordinary skill in the art will realize that the bag  44  and sleeve  46  may be mounted to or secured to the lid  42  in numerous alternative arrangement, for example, by clamping, mechanical fastening, adhesive bonding, welding or other like securing arrangements  
      A male portion  66   a  of a quick connect device  66  is preferably attached at or near the first end  64   a  of the strap and a female portion  66   b  is attached at or near the second end  64   b  of the strap  64 . One of ordinary skill in the art would recognize that other forms of quick connect devices could be used, such as hook and loop material. The debris bag  44 , sleeve  46 , band  68  and strap  64  are further anchored to each other by a grommet  62  at a point opposite the quick connect device  66 . In the preferred embodiment, the grommet  62  is a rivet. Again, one of ordinary skill in the art would recognize that other forms of securing could be substituted such as stitching, adhesively fastening, bolting or clipping without departing from the spirit and scope of the invention.  
      Referring to  FIG. 7 , the debris bag  44  further includes bag handles  74  located at or near the intersection line  76  of the top portion  44   a  and the bottom portion  44   b . In the preferred embodiment, the handles  74  are constructed of polypropylene webbing but one of ordinary skill in the art would recognize that other materials such as cotton or nylon could be substituted without departing from the spirit and scope of the invention. The handles  74  are used for emptying the debris bag  44 .  
      Referring to  FIGS. 1, 4  and  6 , the bag  44  typically hangs within the sleeve  46  such that the bottom portion  44   b  extends beyond the second mouth  46   b  of the sleeve  46 . The ballistic nylon of the bottom portion  44   b  permits dragging of the bottom portion  44   b  on the ground surface  80  during use, typically without significantly damaging the bag  44 . As will be understood by one having ordinary skill in the art, the bottom portion  44   b  does not necessarily drag on the ground surface  80  during use and does not necessarily extend beyond the second mouth  46   b  in the assembled configuration of the bag assembly  20 . For example, the bottom portion  44   b  may be located above the second mouth  46   b  in the assembled configuration and may be constructed of a mesh material that permits airflow therethrough. However, the ballistic nylon material and extension of the bottom end  49   b  beyond the second mouth  46   b  is preferred to maximize the capacity of the chamber  82  and to provide toughness to the bag  44 , respectively.  
      Referring to  FIGS. 1, 4 ,  6  and  7 , in the preferred embodiment, the cylindrical flange  42   b  and the inner cylinder  50  of the lid  42  are mounted coaxially on a central axis  84  of the bag assembly  20 . The flange  42   b  and inner cylinder  50  are preferably mounted coaxially on the central axis  84  to define a generally symmetrical ring-shaped or cylindrical deflection area  51  to create the downward cylindrical flow pattern of the air and debris in the deflection area  51 . The flange  42   b  and inner cylinder  50  are also preferably integrally formed with the top wall  42   a  during construction of the lid  42 .  
      Referring to  FIGS. 4, 5 ,  7  and  8 , in the preferred embodiment, a gap  60  is defined between the sleeve  46  and the bag  44  in the assembled configuration. Due to the mesh construction of the top portion  44   a  and the air impervious construction of the sleeve  46  and the bottom portion  44   b , the air flowing out of the deflection area  51  escapes from the bag assembly  20  by flowing through the mesh top portion  44   a , through the gap  60  and out of the second mouth  46   b.    
      In operation, the collection bag assembly  20  of the lawn vacuum  10  is assembled by securing the debris bag  44  and the sleeve  46  to the lid  42 . The channel  72  of the top portion  48  is wrapped around the outer circumference of the lid  42  and is secured by the band  68  by overlapping the first end  68   a  and the second end  68   b . The debris bag  44  and sleeve  46  are further secured to the lid  42  by securing the strap  64  within the channel  72  over the band  68  and pulling each end of the strap  64   a ,  64   b . This also tightens the band  68  and forms a snug fit. Once the strap  64  is tightened the male portion  66   a  and the female portion  66   b  of the buckle  66  are adjusted and attached to each other to form a tight fit around the flange  42   b  of the lid  42 .  
      The lawn vacuum  10  is started by engaging the engine  18 , which drives the impeller  19 . The speed of the engine  18  is controlled with the throttle control  38 . The initial height of the nozzle  28  is set by adjusting the nozzle height control  34  to a desired minimum height position above the ground surface  80 . As the user moves the lawn vacuum  10  to pick up debris, the impeller  19  creates the vacuum at the inlet  29  and air and debris flow from the nozzle  28  to the collection bag assembly  20  through the nozzle  28 , tube  26 , housing  24  and discharge adapter  22 . When the debris and air, traveling at a high rate of speed, flow through the discharge end  22   b  and enter the debris deflection area  51 , the debris makes initial contact with the top wall  42   a , flange  42   b  and inner cylinder  50  to slow down the speed of the debris. Accordingly, the debris and air are contained in the deflection area  51 , which due to its cylindrical shape and the orientation of the discharge end  22   b  urges the air and debris to flow in a cylindrical and downward path. The flange  42   b , top wall  42   a  and inner cylinder  50  generally prevent the debris bag  44  from tearing or puncturing due to the debris initially impacting these generally rigid and tough components. Therefore, hard debris or sharp objects that enter the collection bag assembly  20  at a high rate of speed generally do not puncture the bag  44  or sleeve  46  because the debris and/or objects generally do not impact the bag  44  or sleeve  46  at high speed. The debris is then forced into a circular path by the solid inner cylinder  50  and lid  42 . The debris then travels to the bottom portion  44   b  in a cyclonic motion. Although the air within the collection bag assembly  20  exits at all points of the debris bag  44 , the majority of the air exits the collection bag assembly  20  near the bottom portion  46   b  of the sleeve  46  because the cyclonic motion of the air is maintained by the air impervious sleeve  46  which forces the air downwardly. The debris is then pushed downwardly by gravity and remains at the bottom portion  44   b  of the debris bag  44  under the urging of additional air and debris that enters the bag  44  through the discharge end  22   b . The weight of the debris within the debris bag  44  may cause the bag  44  to sag and drag against the ground surface  80 . The wear resistant fabric or ballistic nylon material of the bottom portion  44   b  preferably prevents the debris bag  44  from puncturing or tearing. Further, due to this flow pattern, the user does not feel the air blowing on his/her body, specifically in the head and chest area, while the lawn vacuum  10  is moved and is also safe from hard flying objects. Bystanders are also typically protected from coming into contact with the high speed stream of air and/or debris due to this flow pattern.  
      While the lawn vacuum  10  is being pushed over terrain, it may encounter uneven ground. When the nozzle  28  makes contact with a bump in the ground, the curved ends  28   a ,  28   b  of the front end  28  acts as a cam to allow the nozzle  28  to continue to move in a forward direction while pivoting upwardly. The flexible tube  26  allows the nozzle  28  to pivot upwardly while still typically maintaining contact with the ground surface  80 . The front bracket  30  guides the nozzle  28  through the pivotal motion. When the user encounters an obstacle too large for the nozzle  28  to surpass, the nozzle height control  34  located near the handle  78  is remotely controlled for quick height adjustment.  
      It will be appreciated by those skilled in the art that changes could be made to the embodiment described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiment disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.