Abstract:
Improvements to a known convertible barrow for ground level loading with a pivotable wheel carriage ( 36 ) for either resting on the ground for loading or pivoted under the barrow platform ( 20 ) for transporting a load. The improvements locate the pivot points ( 48 ) of the wheel carriage equidistant from the wheel carriage when it is adjacent the inclined rear wall ( 18 ),when it passes the heel end ( 24 ) during pivoting and when it is adjacent the midpoint of the platform to obtain a minimum, tilt angle during conversion. A pivotable gate ( 36 ) provides a closure member ( 56 ) for retaining the load at the time of tilting the barrow and is pivotable about pivot points ( 55 ) on arms ( 58, 60 ) to an open position.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     The present application claims priority of U.S. Patent application Ser. No. 60/547,515 filed Feb. 25, 2004. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     This invention relates to improvements in a known type of convertible barrow for ground level loading and more particularly to an improved placement of the pivoting carriage in an optimum location along with an improved retaining gate which is easy to manipulate. A known type of convertible barrow for ground level loading is disclosed in reexamined U.S. Pat. No. 5,593,271 issued Jan. 14, 1997, and in U.S. Pat. No. 5,810,543 issued Sep. 22, 1998, both in the name of John R. Hall. In the foregoing Hall patents, a pivoting wheel carriage is mounted so as to pivot from a first position in which the wheels rest on the ground behind a flat platform to a second position in which the wheel carriage cross member is disposed at the midsection of the flat platform so as to support the load. The location of the pivot point body of the Hall convertible barrow is such that the barrow is tilted at a rather large angle in order for the wheels to pivot. Also in the Hall patent, a retaining gate is used to close the open end of the barrow, sliding between channel members mounted on opposing sidewalls. This sliding gate requires the user difficulty to manipulate it into the channels. A number of devices are shown in the prior art that are convertible between a snow scoop, which also has wheels so as to be convertible into a handcart. In the snow-scooping mode, handles are used to push up the shovel against the snow so that it enters the open end of the container. When converted into a garden cart, these devices include wheels that are moved into position to support the contents of the cart. U.S. Pat. No. 3,594,932 issued Jul. 27, 1971 to Eriksson discloses a container with to a pivotably mounted carriage in which the wheel axle contacts the rear wall of the container so that it can be transported by tilting the handles downwardly to lift it slightly off of the ground. Eriksson has no retaining gate nor do the wheels pivot to rest under the flat section of the body that rests on the ground.  
         [0003]     U.S. Pat. No. 5,123,187 issued in Jun. 23, 1992 to Zamaria describes a combined snow scoop and multipurpose handcart with a pivoting gate operated by a tether attached to the handle. A pair of wheels are foldable on hinges attached to the sidewalls. When the scoop is resting flat on the ground, the wheels are suspended in the air. There is no cross member beneath the platform supporting the load, so that the load is carried in torsion by the hinges. U.S. Pat. No. 2,930,152 issued Mar. 29, 1960 to Pipkin describes a wheeled shovel with a pivoting wheel carnage mounted on a pivot bracket attached beneath the handle, so that the wheels can unfold from a retainer on the handle to a location beneath the container. A pivoting gate mounted on arms attached to the side of the container swings between a closed position in front of the container to an open position at the rear of the container. The wheel carriage along with the wheels is entirely below the container platform and the device is unsuitable for ground level loading.  
         [0004]     It would be desirable have a convertible barrow which requires the minimum amount of tilting in order to swing the wheels to a location at the midpoint of the body so that the carriage cross member supports the body.  
         [0005]     It would also be desirable to have a convertible barrow with improved means for transporting the barrow in an unloaded condition and to more effectively unload the barrow. It would also be desirable to have a convertible barrow with a retaining gate for the load that is easily closed and opened before the barrow is tilted for loading or unloading.  
       SUMMARY OF THE INVENTION  
       [0006]     Briefly stated, the invention comprises a convertible barrow comprising a body having a substantially flat platform arranged to rest flat on the ground, the platform having a toe end and a heel end and arranged to receive a load at the toe end from substantially ground level, opposed side walls, and a rear wall extending upwardly from the heel end of the flat platform, a handle attached to the body and extending upwardly and rearwardly from the body and arranged such that a user may tilt the body on either the toe end or the heel end of the platform, a wheel carriage having at least two spaced wheels rotatably mounted on a cross member, a pair of wheel pivot arms each pivotably connected to the cross member at one end thereof and pivotably connected to the opposed side walls at first pivot points at the other end thereof and spaced apart by a width greater than the width of the platform, and a gate for retaining the load when the platform is tilted, said convertible barrow being characterized in that:  
         [0007]     said rear wall is inclined rearwardly from the heel end of the platform to define a rear support section and in that the barrow carriage is pivotable from a first position where the wheels and barrow platform are both resting on the ground and said cross member is adjacent said rear support section, through a second position in which said cross member closely passes the heel end of the platform to a third position in which said cross member is adjacent the midpoint of said platform, said first pivot points on the body being located substantially equidistant from the carriage cross member in each of the first, second and third positions, and said convertible barrow being further characterized in that the gate comprises a closure member arranged to extend between the opposed side walls at the toe end of the platform and a pair of pivot arms each being connected to the closure member at one end thereof and pivotably disposed at second pivot points in the opposed side walls at their other ends, said gate being pivotable from an open position toward the rear wall to a closed position on the toe end of the platform with the closure member extending between the opposed side walls to retain the load. 
     
    
     DRAWING  
       [0008]     The invention will be better understood by reference to the following description, taken in connection with the accompanying drawing, in which:  
         [0009]      FIG. 1  is a top plan view of my convertible barrow,  
         [0010]      FIG. 2  is a side elevation view thereof,  
         [0011]      FIG. 3  is an end elevation view thereof,  
         [0012]      FIG. 4  is a partial cross sectional side elevation view,  
         [0013]      FIG. 5  is a simplified schematic side elevation view of the barrow in an unloaded transporting position,  
         [0014]      FIG. 6  is a similar view of the barrow in a loading position with the retaining gate open,  
         [0015]      FIG. 7  is a similar view of the barrow with the gate in a closed position,  
         [0016]      FIG. 8  is a similar view of the barrow swinging the wheel carriage to a loaded transporting position,  
         [0017]      FIG. 9  is a similar view of the barrow transporting a load, and  
         [0018]      FIG. 10  is a similar view of the barrow dumping the load with the gate in the open position. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0019]     Referring now to  FIGS. 1, 2  and  3  of the drawing, a convertible barrow is shown generally at  10 . The convertible barrow  10  comprises a body  12  with opposed sidewalls  14 ,  16 , and an inclined rear wall  18 , extending upwardly from a flat platform  20 . The platform  20  extends between a “toe” end  22  and a “heel” end  24 .  
         [0020]     Attached to body  12  is a handle  26  comprising two spaced longitudinal members  28 ,  30  extending upwardly and rearwardly from body  12  and joined by a cross member  32 . The lower ends of the longitudinal members  28 ,  30  are inserted into sockets molded into sidewalls  14 ,  16  of the body, one such socket being shown at  34 . The lower ends are also bolted to the sidewalls by bolts  29 ,  31 .  
         [0021]     A pivotable wheel carriage, shown generally at  36 , comprises a pair of wheels  38 ,  40  rotatably mounted on an axle  42 . Axle  42  comprises a carriage cross member, and could also be a channel, I-beam, or similar load supporting member upon which wheels  36 ,  38  are rotatably mounted. The wheel carriage  36  includes a pair of pivot arms indicated in  FIG. 1  by reference numbers  44 ,  46 . One end of each of the pivot arms  44 ,  46  is pivotably mounted on axle  42 . The other end of each of the pivot arms  44 ,  46  is pivotably mounted on a respective one of opposed sidewalls  14 ,  16  of the body. One such pivot point is seen at reference number  48  in  FIG. 2 , designated as a “first pivot point”. A corresponding “first pivot point” is located on the opposed sidewall.  
         [0022]     The wheel carriage  36  is pivotable as best seen in  FIG. 2  from a first position in which the wheels rest on the ground through a second position in which the axle  42  just clears the heel end  24  of the platform  20  to a third position in which the axle  42  rests beneath the midpoint of the platform  20 . These three positions are indicated in  FIG. 2 . The first position with axle  42  adjacent a rear support section of the inclined back wall  18  is shown in full lines. The second position with the age just passing heel  24  is shown in dashed lines by reference number  50 . The third position with the axle beneath the midpoint of the platform  20  is shown in dashed lines at reference number  52 .  
         [0023]     In accordance with one aspect of the present invention, the preferred construction employs a rear wall  18  that is inclined so as to form an included angle with platform  20  about the heel  24  on the order of 120°. See  FIG. 4  for this preferred inclination where the axle  42  is positioned closely adjacent the rear wall. The preferred location for first pivot point  48  is along a vertical line drawn from a point on the platform that is one quarter of the distance from the heel to the toe of the platform. The height of pivot point  48  along this vertical line is then determined by the chosen diameter of wheels  36 ,  38 .  
         [0024]     The sidewalls  14 ,  16  of the body may be flared out from the platform toward the front part of the body as indicated in the end elevation view of  FIG. 3 . Wheels  36 ,  38  are spaced apart from one another by a width at least as great as the width of a central support section located midway between the heel end and toe end of the platform. The wheel spacing may be increased slightly to avoid interference with the sidewalls  14 ,  16  if they are flared outwardly. In accordance with another aspect of the present invention, as best seen in  FIG. 4 , a pivotable gate, shown generally at  54 , is mounted to pivot around “second pivot points”  55  in the opposed sidewalls  14 ,  16 . As seen in the drawing, the second pivot points  55  are located at a separate location spaced from the first pivot points on the opposed sidewalls. However, the second pivot points may be located on a common support together with the first pivot points in order to simplify the mounting of both the pivotable gate  54  and the wheel carriage  36 . Gate  54  includes a closure member  56  that blocks the open end of body  12 , and a pair of pivot arms  58 ,  60 . The pivot arms include pivot pins  62 ,  64  that are contained in pivot holes formed in bosses  64 ,  68  on the respective sidewalls. Pivot arms  58 ,  60  are flexible enough in a lateral direction to allow the pivot pins  62 ,  64  to be disengaged front the sidewalls in order to remove the pivotable gate  54 . Closure member  56  preferably includes a lip  70  that extends beyond the end of body  12 .  
         [0025]     Referring to the cross section of  FIG. 4 , more details can be seen of the pivotable gate  54 . Gate  54  pivots from a closed position shown in the drawing to an open position indicated by the dashed lines  72 . Pivotable gate  54  may be locked in the open position  72  by a suitable latching mechanism  74 . This latching mechanism  74  may be a suitable spring biased hook that will catch on the lip  70  to hold the pivoting gate open or may be a spring clip attached to the gate pivot arms that engages the handle  26 .  
       INDUSTRIAL APPLICABILITY  
       [0026]     Operation of the invention will be understood by reference to the simplified schematic views of  FIGS. 5-10 .  FIG. 5  shows the unloaded transporting position. The pivotable gate  54  is in the open position. By depressing the handle  26 , platform  20  is tilted back on the heel and the rear support section of the inclined back wall  18  of barrow  12  is then supported by the axle  42 . Platform  20  clears the ground and the barrow  12  may be easily transported to the loading site.  FIG. 6  illustrates the loading position with the platform  20  flat on the ground and pivotable gate  54  open. A load of material to be transported can be raked or shoveled into the open end of body  12 . Alternately, a heavy object may be shoved into the open end of body  12  from ground level. In the latter case, the pivotable gate  54  might or might not be necessary and may remain in the open position for a load such as a potted plant or refuse container.  
         [0027]      FIG. 7  illustrates the barrow in the same position as  FIG. 6 , but with the pivotable gate  54  pivoted into a closed position preparatory to tipping the barrow on the toe end of the platform to enable swinging the wheel carriage. The second pivot points for the pivotable gate are located so as to enable the gate to pass above a load that is swept or raked onto the platform when the gate is pivoted from the open position to the closed position.  
         [0028]      FIG. 8  illustrates the swinging of the wheel carriage  36  into the loaded transporting position. In order to accomplish this, the handle  26  is raised by the operator to tilt the platform  20  on the toe end, raising the heel end so that the wheel carriage  36  may swing freely on pivot arms  44 ,  46 . The location of the first pivot points  48 , as previously described, requires a minimum tilting of platform  20  during loading. The closure member  56  of the pivotable gate  54  keeps the load from coming out of the open end of body  12  when the platform is tilted.  
         [0029]     The carriage  36  swings from the first position shown in  FIGS. 6 and 7  past the heel end  24  of the platform. Swinging of the wheel carriage, aided by rolling of the wheels, continues until the axle or other cross member of the carriage  36  reaches the midpoint of platform  20  as shown in  FIG. 9 . The load is then transported to a dumping site by pushing or pulling handle  26 , with the load balanced and primarily supported by the cross member in a previously known fashion as set forth in the aforementioned Hall U.S. Pat. Nos. 5,810,543 and 5,593,271.  
         [0030]     Upon reaching the dumping site, pivotable gate  54  is pivoted to the open position. If desired, latch  74  may retain it in the open position, but this is not absolutely necessary. The load is dumped by the operator elevating the handle  26  so that the body tips forward on the toe end of platform  20 . Thus, the load is discharged from the open end of the body.  
         [0031]     While there has been described what is considered to be the preferred embodiment of the invention, other modifications will occur to those skilled in the art, and it is desired to secure in the appended claims all such modifications as fall within the true spirit and scope of the invention.