Patent Document

BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates in general to lifting apparatus, and particularly to a lifting apparatus for assisting an operator to lift and maneuver a wheelbarrow.  
         [0003]     2. Description of Related Art  
         [0004]     A wheelbarrow is a simple cart commonly used to transport loads of materials over relatively short distances. A wheelbarrow typically has two handles, one wheel and a container and can be operated by a single person. Conventionally, using a wheelbarrow involves the following steps: loading material to be moved into the container, griping a handle with each hand and lifting the handles so the wheelbarrow&#39;s wheel and the operator&#39;s hands and arms are bearing the combined weight of the wheelbarrow and the material in the container. The operator may then push the wheelbarrow to the desired location where the container can be emptied.  
         [0005]     A wheelbarrow bearing a particularly heavy load or is to be transported a relatively long distance or is to be lifted by a physically weak operator may be uncomfortable or unsafe for the operator&#39;s hands and arms to support and thus an apparatus for assisting in lifting and maneuvering a wheelbarrow is desirable.  
         [0006]     Lifting harnesses, such as U.S. Pat. No. 2,651,441 issued Sep. 8, 1953 to Rau et al and U.S. Pat. No. 2,441,115 issued May 4, 1948 to Lambert, assist in lifting a variety of heavy loads and may provide a solution transferable to wheelbarrows.  
         [0007]     Prior art wheelbarrow accessories attempt to preserve the advantages of the basic wheelbarrow while enhancing control and power. U.S. Pat. No. 5,346,232 issued Sep. 13, 1994 to Bushon proposes to solve the lifting requirements of a common wheelbarrow by placing a strap between the handles to be pushed with the operator&#39;s thigh muscles. Long-term use of this device would repetitively exert pressure on a narrow area of the operator&#39;s thigh, potentially making the device uncomfortable or unsafe to use.  
         [0008]     U.S. Pat. No. 915,628 issued Mar. 16, 1909 to Seymore describes an apparatus employing a series of pulleys mounted upon a yoke. A rope or cable runs through the pulleys and has hooks on either end for attaching to the handles of a wheelbarrow. This apparatus does not provide any means of adjustment for operators or wheelbarrows of varying sizes and the pulley system is susceptible to rusting or becoming jammed with dirt and debris. Further, the yoke of this apparatus is made of a rigid material surrounding a large portion of the operator&#39;s neck, raising safety concerns in a modern work environment.  
         [0009]     What is needed is an apparatus capable of safely transferring the weight of a wheelbarrow away from the operator&#39;s hands and arms both for the sake of comfort and so the hands can be better used to safely maneuver the wheelbarrow.  
       SUMMARY OF THE INVENTION  
       [0010]     According to an embodiment of the invention there is an apparatus for assisting in lifting and maneuvering a wheelbarrow having first and second handles, the apparatus comprising a strap, a first engagement means secured to the strap for engaging the first handle of the wheelbarrow, a second engagement means secured to the strap for engaging the second handle of the wheelbarrow, and a means for adjusting a distance along the strap separating the first and second engagement means.  
         [0011]     According to another embodiment of the invention there is an apparatus for assisting in lifting and maneuvering a wheelbarrow having first and second handles, the apparatus comprising a strap having a first end and a second end, first engagement means secured to the strap for engaging the first handle of the wheelbarrow, second engagement means secured to the strap for engaging the second handle of the wheelbarrow, and a flexible pad attached to the length of the strap.  
         [0012]     According to another embodiment of the invention, there is an apparatus for assisting in lifting and maneuvering a wheelbarrow having first and second handles, the apparatus comprising a lifting strap, and a first buckle through which the strap is threaded to define a first loop for engaging the first handle of the wheelbarrow. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]      FIG. 1  is a side view of a wheelbarrow being lifted with the aid of a lifting apparatus embodying the present invention.  
         [0014]      FIG. 2  is a perspective view of the apparatus shown in  FIG. 1 .  
         [0015]      FIG. 3  is a perspective view of a detail of a second lifting apparatus embodying the present invention.  
         [0016]      FIG. 4  is a front view of a third lifting apparatus embodying the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0017]     As shown in  FIG. 1 , a conventional wheelbarrow  2  includes handles  4 , a container  8  disposed above the handles, legs  12  mounted below the handles and wheel  16  connected to the handles via an axle assembly  18 . When in a resting position, wheel  16  and legs  12  form a tripedal support for container  8 . To transport wheelbarrow  2 , operator  20  grasps grips  22  of handles  4  and lifts them to a convenient height, causing the wheelbarrow to pivot around the rotational axis of axle assembly  18  so that legs  12  rise off the ground. Wheel  16  is free to rotate, allowing operator  20  to push wheelbarrow  2  to the desired destination. Operator  20  discharges the contents of container  8  by rotating handles  4 , for example by lowering the left handle and raising the right handle, causing wheelbarrow  2  to rotate with respect to the point where wheel  16  contacts the ground (not shown).  
         [0018]     Referring to  FIG. 2 , the illustrated lifting apparatus comprises a strap  32  of fabric webbing threaded through rectangular passage  43  in a length of flexible tubular padding  44 . Padding  44  may be composed of a resilient foam material. Each end of strap  32  is threaded through an adjustable locking buckle  40 , an eye  39  of a hook  36 , and back through the buckle. Buckle  40  is a conventional buckle that includes a releasable locking mechanism.  
         [0019]     Referring to  FIG. 4 , the locking mechanism of illustrated buckle  40  comprises toothed barrel  45  and a toothed cam  46 . Toothed cam  46  is pivotable, relative to the barrel, between an engaged position, for allowing strap  32  to move relative to the buckle in only a tightening, or shortening, direction, and a released position, for allowing the strap to move both in the tightening direction and in a loosening, or lengthening, direction. Pulling strap  32  in the loosening direction when cam  46  is in the engaged position jams the strap between barrel  45  and the cam, preventing movement of the strap. A lever  47  assists in moving cam  46  to the released position. A spring (not shown) holds cam  46  in the engaged position unless operator  20  depresses the lever  47 .  
         [0020]     Referring again to  FIG. 1  the lifting apparatus assists operator  20  by transferring the load to be supported by the operator from operator&#39;s hands  24  to operator&#39;s shoulders and back  28 . To use the lifting apparatus, operator  20  would pre-adjust the effective length of strap  32 , i.e. the distance between hooks  36 , using adjustable locking buckles  40 . In use the appropriate effective length will vary by situation, but it can be estimated by placing strap  32  around the back of the operator&#39;s neck, with padding  44  centered approximately on the spine. The free ends of strap  32  should then be hanging in front of operator&#39;s arms  24 . Each end should be adjusted so hooks  36  hang slightly below the operator&#39;s fingertips when the arms are at the sides.  
         [0021]     To engage wheelbarrow  2  with the apparatus, the operator stands between handles  4  and places strap  32  on the operator&#39;s neck with padding  44  centered on the spine. If hooks  36  can reach handles  4  while the operator is standing upright, the effective length of strap  32  is too great and must be reduced. After ensuring the effective length of strap  32  is properly adjusted, the operator bends or squats down in order to lower hooks  36  and temporarily engage them with handles  4  while maintaining slack in the strap. It will be appreciated that once the effective length of strap  32  has been adjusted for the particular operator and the particular wheelbarrow, it will not generally be necessary to change the adjustment.  
         [0022]     When hooks  36  are engaged with handles  4 , operator  20  begins to stand, taking hold of grips  22  to aid in balancing wheelbarrow  2 . When strap  32  becomes taut legs  12  of wheelbarrow  2  lift off the ground and a significant portion of the weight of the wheelbarrow will be transferred through the strap to operator&#39;s shoulders and back  28 . Padding  44  on strap  32  distributes the load across a greater surface area of operator&#39;s shoulders and back  28  for the operator&#39;s comfort. When lifting the wheelbarrow, the operator preferably will lift by straightening at the knees and hips, keeping the back as upright as possible so as to reduce the possibility of injury. By transferring the weight of wheelbarrow  2  to the operator&#39;s shoulders and back through strap  32 , the operator uses the strongest muscles to lift the wheelbarrow and is better able to use hands and arms to aid in balancing and maneuvering the wheelbarrow. Thus the lifting apparatus can enable the operator to lift heavier loads.  
         [0023]     Discharging the contents of wheelbarrow  2  is performed in the conventional manner described above. When operator  20  raises one handle above the other strap  32  will move through passage  43  of padding  44  while the padding remains in place on the neck of the operator.  
         [0024]     Hooks  36  may be sized to fit snugly on wheelbarrow handles  22  so that they remain on handles  22  when operator  20  releases tension on strap  32 . Alternatively, the ends of hooks  36  may be designed so that their ends extend partially over the tops of handles  22  so that they remain on the handles when operator  20  releases tension on strap  32 .  
         [0025]     In a second embodiment of the invention, strap  32  is attached to handles  4  by means of rings  38 , as shown in  FIG. 3 . Instead of applying the hooks from below, the operator will thread handles  4  through rings  38 . The hooks  36  or rings  38  allow the operator to easily slip the lifting mechanism off handles  4 .  
         [0026]     In a third embodiment of the invention, the hook or ring is omitted and the handle is threaded through loop  52  formed in strap  32  by locking cam buckle  40 , as shown in  FIG. 4 .  FIG. 4  also illustrates additional padding  49  in central region  50  of padding  44  to provide additional protection to the operator&#39;s neck.  
         [0027]     The illustrated embodiments of the invention are compatible with a wheelbarrow of similar design to the conventional wheelbarrow described above. The illustrated embodiments of the invention do not interfere with the operation of other conventional wheelbarrow accessories and safety devices, such as the “Wheelbarrow Braking System” described in U.S. Pat. No. 5,690,191 and the “Wheelbarrow Disk Brake Assembly” described in U.S. Pat. No. 6,443,267 or the various versions of the motorized wheelbarrows such as the “Motorized Wheelbarrow” described in U.S. Pat. No. 5,878,827 and the “Motorized Wheelbarrow” described in U.S. Pat. No. 5,465,801.  
         [0028]     Although inexpensive to manufacture, a lifting apparatus in accordance with the invention thus allows an operator to easily lift, control and maneuver even very heavily loaded wheelbarrows and helps reduce operator fatigue.  
         [0029]     It will be appreciated that the invention is not restricted to the particular embodiments that have been described and illustrated, and that variations may be made therein without departing from the scope of the invention as defined in the appended claims and equivalents thereof. Unless the context indicates otherwise, a reference in a claim to the number of instances of an element, be it a reference to one instance or more than one instance, requires at least the stated number of instances of the element but is not intended to exclude from the scope of the claim a structure or method having more instances of that element than stated.

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