Abstract:
A wheeled lifting device particularly well suited for lifting a stack of nested waste containers. The device includes a lift arm, a handle, and a pair of wheels. The wheels move in an under-center action under the lift arm to lift one side of a stack of containers. When the stack is so lifted it is supported for rolling movement on the wheels of the device and on the wheels of the lower-most container.

Description:
BACKGROUND OF INVENTION  
         [0001]    The present invention relates to container support apparatus and, more specifically, to a wheeled carrier for moving stacks of containers.  
           [0002]    Various wheeled carriers are known in the prior art. These wheeled carriers, commonly referred to as hand trucks, are typically constructed from metal tubing. A wheeled carrier generally consists of wheels, a support platform, and a handle assembly. A container or other object is placed on the support platform and the user tilts the carrier so only the wheels are in contact with the ground. The user then pulls the carrier to move the container or other object.  
           [0003]    Several wheeled carriers have been specifically designed to facilitate the movement of large bins, such as waste receptacles. These wheeled carriers are designed to keep the bin from tipping or sliding during transport. In general, these carriers have attachment devices, such as clamps, that grasp the bin prior to and during transport. Alternatively, the bin may be placed within a frame attached to the carrier. To use the carrier, the bin is lifted and placed on the support platform. If the carrier has a frame, the bin is placed within the frame.  
           [0004]    Basic wheeled carriers are effective only when the item to be transported can be lifted and placed on the carrier. However, due to the weight of items needing to be moved in an industrial setting, it is impractical in many instances to lift the item prior to transport. Some wheeled carriers eliminate the support platform. Instead, these wheeled carriers include attachment devices such as clamps to grasp the item prior to transport. After connecting the attachment devices to an item, the wheeled carrier is usually tilted and pulled in the same manner as the prior art wheeled carriers.  
           [0005]    These modified wheeled carriers are useful when a section of the item to be transported can be securely clamped. For instance, when transporting a gas cylinder, the attachment device would be connected to the upper rim of the cylinder. In general, only one article can be securely transported on a carrier. Additionally, time must be taken prior to transport to connect the attachment device to the item. Typically, multiple sides of the item must be accessible to connect the attachment device to the item.  
           [0006]    In an industrial setting, specifically in the waste receptacle industry, items are often stacked during shipment and storage. A stack of items is generally too heavy to lift and place on a conventional hand truck. Additionally, during transport and storage, the stacks are packed tightly to maximize the use of space. As a result, the modified carriers described above can not be used. Instead, fork lift trucks are commonly used to transport stacks of items. Special lift devices have to be attached to each fork lift truck to allow the fork lift to properly interact with a stack so the stack can be lifted and moved. The special lift devices are expensive, and fork lift trucks are not available at all locations where transport of items is required.  
           [0007]    When a fork lift truck is not used, the stacks are generally moved by hand. Generally, personnel must be able to access the sides of a stack to prevent the stack from tipping during movement. Space is left when packing the items to allow personnel sufficient room to move the items manually when necessary. This wasted space is an added expense when storing or shipping items. Additionally, there are significant safety concerns when moving the stacks by hand since stacks can tip.  
         SUMMARY OF THE INVENTION  
         [0008]    The aforementioned problems are overcome by the present invention wherein a wheeled carrier, or dolly, is provided to interfit with the front of a stack of typical commercial waste receptacles to provide a second set of wheels. When connected to the dolly, both the wheels of the waste receptacle and the wheels of the dolly support the stack for easy, safe, rolling movement.  
           [0009]    The dolly includes a container arm for engaging one of the containers. The dolly further includes wheels that, through an “under-center” action, lift the containers slightly. A handle opposite the container arm assists in moving the dolly through its under-center action, and then assists in transporting the containers.  
           [0010]    In a preferred embodiment a substantially U-shaped step bar is attached to the base of the handle unit. The step bar allows a user to more easily push the wheels through the under-center action, and thus lift the stack for rolling transport.  
           [0011]    In a preferred embodiment, a kick stand is rotatably attached to the step bar. By rotating the kick stand so it is in contact with the ground, the user can rest the dolly in an upright position allowing the dolly to be more easily accessed when needed.  
           [0012]    This invention provides a simple and inexpensive dolly for moving stacks of items in a tightly packed space. The lift device interacts with the front of a typical commercial waste receptacle to connect the dolly to the waste receptacle. Once connected, the dolly is designed to lift the stack so only the wheels of the lower-most container of the stack remain in contact with the ground. This configuration allows a stack of receptacles to be moved even if only one side of the stack is accessible. Additionally, the dolly can be easily maneuvered in small, enclosed spaces such as an over-the-road trailer. Since only one side of a stack must be accessed to move the stack, the items can be packed tightly during shipping and storage. This will significantly decrease the costs of shipping and storing items. Further, since the wheels of the dolly and the wheels of the base unit are in contact with the ground, the stack is very stable when being moved.  
           [0013]    These and other objects, advantages, and features of the invention will be readily understood and appreciated by reference to the detailed description of the preferred embodiment and the drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]    [0014]FIG. 1 is a perspective view of the dolly manufactured and being used in accordance with a preferred embodiment of the present invention;  
         [0015]    [0015]FIG. 2 is a side view of the dolly;  
         [0016]    [0016]FIG. 3 is a front view of the dolly;  
         [0017]    [0017]FIG. 4 is a rear view of the dolly;  
         [0018]    [0018]FIG. 5 is a side view of the dolly in use;  
         [0019]    [0019]FIG. 6 is a side view of the dolly in use;  
         [0020]    [0020]FIG. 7 is a side view of the dolly in use. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0021]    A dolly  10  in accordance with a preferred embodiment of the present invention is shown in FIG. 1. The dolly  10  is generally comprised of a handle unit  12  and a lift unit  14 . In a preferred embodiment, wheels  16  are attached to the base of handle unit  12 . First attachment bar  18  and second attachment bar  20  connect the lift unit  14  to the handle unit  12 . The lift unit  14  is configured to connect with the front side of a typical commercial waste receptacle  22 . When the dolly  10  is tilted toward the waste receptacle  22 , the lift unit  14  fits within a groove  24  running along the front of the waste receptacle  22 . While the invention will be described in relation to use with standard commercial waste receptacles, the present invention is well suited for use with other items.  
         [0022]    The dolly  10  will now be described in greater detail with reference to FIGS.  2 - 7 . As can be seen in FIG. 2, the dolly  10  includes a handle unit  12  and a lift unit  14 . First attachment bar  18  and second attachment bar  20  connect the handle unit  12  and the lift unit  14 . Each attachment bar  18 , 20  has a first end  26  and a second end  28 . The handle unit  12 , lift unit  14  and first and second attachment bars  18 , 20  can be made of any material having sufficient strength to support the items being moved during transport. In a preferred embodiment, these elements are made of steel tubing.  
         [0023]    The first end  26  of each of first attachment bar  18  and second attachment bar  20  is connected to the handle unit  12 . Each of first attachment bar  18  and second attachment bar  20  preferably protrudes from the handle unit  12  at slightly less than a 90 degree angle, each of first attachment bar  18  and second attachment bar  20  pointing downward once connected. The second end  28  of each of first attachment bar  18  and second attachment bar  20  is connected to the lift unit  14 . Each of first attachment bar  18  and second attachment bar  20  is preferably form a 90 degree angle with lift unit  14  when connected. In a preferred embodiment, first attachment bar  18  is longer than second attachment bar  20  so that when assembled lift unit  14  protrudes at an angle from handle unit  12  when handle unit  12  is upright.  
         [0024]    In a preferred embodiment, a step bar  30  is connected to the handle unit  12 . The step bar  30  is preferably substantially U-shaped as can be seen in FIG. 1. In a preferred embodiment, the step bar  30  is made of steel tubing, but any other suitable material can be used. The step bar  30  is connected substantially perpendicularly to handle unit  12  on the side of handle unit  12  opposite the first attachment bar  18  and second attachment bar  20  so that the open portion of the step bar  30  is attached to the handle unit  12 . The step bar  30  can be attached to the handle unit  12  using any conventional means. In a preferred embodiment, the step bar  30  is welded to the handle unit  12 .  
         [0025]    In a further preferred embodiment, a connection tab  32  extends downwardly from step bar  30 . The connection tab  32  is preferably connected to step bar  30  at the end of step bar  30  opposite handle unit  12 . The connection tab  32  can be connected to the step bar  30  by any conventional means. In a preferred embodiment, the connection tab  32  is welded to the step bar  30 .  
         [0026]    A kick stand  34  is rotatably connected to connection tab  32 . The kick stand  34  is preferably long enough to contact the ground when the lift unit  14  is substantially perpendicular to the ground. The kick stand  34  is rotatably connected to the connection tab  32  using any conventional means. In a preferred embodiment, a bolt  36  is used to connect kick stand  34  to connection tab  32 . The kick stand  34  and connection tab  32  can be made of any material with sufficient strength to support the weight of the dolly. In a preferred embodiment, the kick stand  34  and connection tab  32  are metal tubes.  
         [0027]    As can be seen more clearly in FIG. 3, the lift unit  14  includes a shaft  40  having a first end  42  and a second end  44  and first and second lift bars  46 , 48 . In a preferred embodiment, each of these elements is substantially straight. The first attachment bar  18  and second attachment bar  20  are preferably connected to the shaft  40 . The first attachment bar  18  and second attachment bar  20  can be connected to the shaft  40  by any conventional means, but in a preferred embodiment they are welded to the shaft  40 .  
         [0028]    The first lift bar  46  is connected perpendicularly to the first end  42  of the shaft  40 . The second lift bar  48  is connected perpendicularly to the second end  44  of the shaft  40 . The first lift bar  46  and second lift bar  48  can be connected to the shaft  40  by any conventional means. In a preferred embodiment, the first lift bar  46  and second lift bar  48  are welded to the shaft  40 . In a preferred embodiment, the lift unit is configured to allow the first lift bar to fit  46  snugly within the Upper Lift Pocket  47  and allow the second lift bar  48  to fit snugly within the lower attachment points (not shown) of a typical commercial waste receptacle complying with ANSI standards for Waste Containers—Compatibility Dimensions.  
         [0029]    The construction of the handle unit  12  can be more clearly seen with reference to FIGS. 3 and 4. The handle unit  12  includes left and right support bars  50 ,  52 , a handle  54 , first and second cross bar  56 , 58 , and axle  60 , each of which is substantially straight in the preferred embodiment. Each of left support bar  50  and right support bar  52  has a first end  62  and a second end  64 . The first end  62  of each left support bar  50  and right support bar  52  is preferably perpendicularly connected to handle  54  so that when left support bar  50  and right support bar  52  are connected to handle  54 , left support bar  50  and right support bar  52  are substantially parallel. In a preferred embodiment, when handle  54  is connected to left support bar  50  and right support bar  52 , the length of handle  54  extends beyond left support bar  5   oe    0  and right support bar  52 . Handle  54  can be connected to left support bar  50  and right support bar  52  by any conventional means, but in a preferred embodiment handle  54  is welded to left support bar  50  and right support bar  52 .  
         [0030]    The second end  64  of each of left support bar  50  and right support bar  52  is preferably perpendicularly connected to axle  60 . Left support bar  50  and right support bar  52  are connected to axle  60  by any conventional means, but in a preferred embodiment left support bar  50  and right support bar  52  are welded to axle  60 . When connected, the length of axle  60  preferably extends beyond left support bar  50  and right support bar  52 . Wheels  16  are preferably attached to axle  60  to facilitate movement of the dolly  10 . In a preferred embodiment, a wheel  16  is preferably rotatably attached to each end of axle  60 . However, any number of wheels can be used and the method and location of attachment will depend on the number of wheels. Any conventional manner for rotatably attaching wheels can be used, and many such methods are known in the art. In an alternate embodiment, instead of wheels a slippery “skid” is attached to axle  60 . Such articles are commonly known in the art, and any such conventional article can be used.  
         [0031]    Each of the first and second cross bars,  56  and  58  has a first end  68  and a second end  70 . The first end  68  of first cross bar  56  is perpendicularly connected to left support bar  50  and the second end  70  of first cross bar  56  is perpendicularly connected to right support bar  52 . The first end  68  of second cross bar  58  is perpendicularly connected to left support bar  50  and the second end  70  of second cross bar  58  is perpendicularly connected to right support bar  52 . First cross bar  56  and second cross bar  58  are connected to left support bar  50  and right support bar  52  by any conventional means, but in a preferred embodiment the elements are welded together.  
         [0032]    In a further preferred embodiment, first attachment bar  18  is connected to first cross bar  56  and second attachment bar  20  is connected to second cross bar  58 . First and second attachment bars  18 , 20  can be connected to first and second cross bars  56 , 58  by any conventional means, but in a preferred embodiment first and second attachment bars  18 , 20  are welded to first and second cross bars  56 , 58 . The step bar  30 , if used, is preferably perpendicularly attached to second cross bar  58  so the step bar  30  can be easily accessed by the user. The step bar  30  can be attached to second cross bar  58  in any conventional manner, but in a preferred embodiment step bar  30  is welded to second cross bar  58 .  
         [0033]    A method of using the dolly  10  is shown in FIGS.  5 - 7 . While the use will be described with reference to a single waste receptacle, the invention is suitable for use with stacks of items as well. To use the dolly  10  with a typical commercial waste receptacle, the dolly  10  is first rolled to the stack. The lift unit  14  is placed in contact with the base waste receptacle  22  so the first lift bar  46  fits within the upper lift envelope  47 . Using the handle unit  12 , the dolly  10  is then tilted so the second lift bar  48  fits within the lower attachment points (not shown). This positioning will connect the stack to the dolly  10 . The dolly  10  is then tilted further so only the wheels  80  of the waste receptacle  22  are in contact with the ground. The user can utilize the step bar  30 , if present, to aid in tilting the dolly  10 . After tilting the stack, the dolly  10  is pulled to move the items. The reverse process is used to place the stack in its new position.  
         [0034]    The above description is that of a preferred embodiment of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law including the doctrine of equivalents. Any reference to claim elements in the singular, for example, using the articles “a,” “an,” “the” or “said” is not to be construed as limiting the element to the singular.