Abstract:
The portable lift apparatus described herein, provides for the lifting of heavy objects such as motor vehicle engines, fence posts and the like. In the preferred embodiment, the portable lift apparatus has a base that attaches to a common receiver hitch attached to a vehicle or other heavy equipment. An upper arm extends upward at an angle. The main frame, of the portable lift apparatus in the preferred embodiment, is made of tubular stock that is welded together. A pulley wheel and a pair of cable guides route cable from a winch to the object desired to be moved. A removable support block cover covers the dolly wheel that is attached to the stabilizing jack. The dolly wheel allows for portability and the removable support block cover provides extra support for loads during lifting.

Description:
RELATED APPLICATIONS  
         [0001]    The present invention is a continuation of Disclosure Document Number 482,855 filed on Nov. 20, 2000.  
         FIELD OF THE INVENTION  
         [0002]    The present invention relates generally to lifts. More specifically, the present invention relates to a portable lift used to lift and move heavy objects.  
         BACKGROUND OF THE INVENTION  
         [0003]    There are many times when a heavy object must be lifted and typical aides such as cranes, tow motors, tow trucks or the like are neither available nor feasible. Examples of these tasks are the lifting of an engine out of a motor vehicle at a home garage or a small service center, the setting of fence posts or the lifting of heavy lumber at a farm or home. Usually in such instances a small hydraulic jack with a metal frame or casters must be rented—an item that is not very mobile especially over rough surfaces. Another common means of completing such tasks is the enlistment of the help of friends, neighbors or family, who may not be readily available or willing to help. Accordingly, there exists a need for a means by which heavy loads can be lifted in a simple manner without the above listed disadvantages. The present invention fulfills this need.  
         SUMMARY OF THE INVENTION  
         [0004]    The present invention, the portable lift apparatus, provides for the lifting of heavy objects such as motor vehicle engines, fence posts and the like. In the preferred embodiment, the portable lift apparatus attaches to a common receiver hitch and extends out from the rear of a vehicle. An upper arm extends upward at an angle of approximately sixty degrees to a total height of approximately ninety-nine inches. The main frame of the portable lift apparatus in the preferred embodiment, is made of two inch tubular stock that is welded together. Also in the preferred embodiment, a pulley and a cable guide route a high strength steel cable to either a manual or an electric winch. A support plate or dolly wheel provides extra support for loads up to one thousand pounds when the lift is constructed from aluminum and up to fifteen hundred pounds when the lift is constructed from steel. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]    The advantages and features of the present invention will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings, in which like elements are identified with like symbols, and in which:  
         [0006]    [0006]FIG. 1 is a side view of the portable lift apparatus with the dolly wheel in use.  
         [0007]    [0007]FIG. 2 is a side view of the portable lift apparatus with the support plate in use.  
         [0008]    [0008]FIG. 3 is a front view of the portable lift apparatus. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0009]    The preferred embodiment of the present invention, the portable lift apparatus  10  is shown in FIGS.  1 - 3 . In the preferred embodiment, the main body pieces  20 ,  22 ,  25 ,  54  of the portable lift apparatus  10  are constructed from aluminum. One of ordinary skill in the art would readily recognize that other materials, including, but not limited to, steel can be used to make the portable lift apparatus  10 . The overall cost of manufacture and strength of the apparatus  10 , both depend on the type of material chosen to construct the main body pieces  20 ,  22 ,  25 ,  54 .  
         [0010]    As can be seen in both FIGS. 1 and 2, the portable lift apparatus  10  has a base  22 . Said base  22  is preferably devised to mate at one end thereof with a standard female hitch  62  mounted to a motor vehicle  60 . The base  22  can be adapted to fit a receiver  62  from one and one-quarter inches to two inches in size. In the preferred embodiment, a five-eighths inch hitch pin  23  is used to fasten the portable lift apparatus  10  to a motor vehicle. A safety clip (not shown) is preferably used to secure the base  22  in place. One of ordinary skill in the art would readily recognize that a safety clip need not be used and that the hitch pin  23  can be any number of different sizes such that it coordinates with the hitch being used.  
         [0011]    In the preferred embodiment, attached to the end of the base  22  opposite the end that is devised to engage a vehicle hitch, preferably by being welded thereto, is the boom  20 . It is preferred that the boom  20  be welded to the base  22  at an upward angle for maximum strength and stability. This is preferably achieved by using a miter saw to cut the base  22  at a seven degree angle and then mating the boom  20  therewith. One of ordinary skill in the art would recognize, however, that the size of the angle can be altered. The totality of the boom  20  encompasses a lower boom  20 A and an upper boom  20 B. The upper boom  20 B fits inside of the lower boom  20 A such that the boom  20  is telescoping in nature and the height thereof can be easily adjusted. In the preferred embodiment, a five-eighths inch hitch pin  23  is used to secure the upper boom  20 B after it has been extended. The hitch pin  23  is inserted through the single aperture  19  at the highest end of the lower boom  20 A and through the nearest aperture  21  on the upper boom  20 B. One of ordinary skill in the art would readily recognize that the hitch pin  23  need not be a five-eighths inch pin and can be any number of sizes. The size of the hitch pin  23  must coordinate, however, with the size of the single aperture  19  in the lower boom  20 A and the apertures  21  in the upper boom  20 B. In the preferred embodiment, the maximum length of the boom  20  is four and one-half feet in its extended position, and the minimum length of the boom is four feet, in its retracted position. One of ordinary skill in the art would recognize that although the length of the boom  20  can be shorter that four feet, it is not safe for the length of the boom  20  to be longer that four and one-half feet and still lift up to one thousand pounds, unless other structural changes, such as constructing the main body pieces,  20 ,  22 ,  25  and  54  from steel instead of aluminum, are made in the portable lift apparatus  10 . The total vertical height, in the preferred embodiment, from the ground to the top of the boom  20 , when fully extended, is ninety-nine inches such that fence posts and poles up to fifteen feet in length can be handled and installed. In the preferred embodiment, the main frame of the portable lift apparatus  10 , including the base  22  and the boom  20  is constructed from two inch tubular metal stock. As mentioned above, it is preferred that the portable lift apparatus  10  be constructed from steel or aluminum for structural integrity and strength. One of ordinary skill in the art would recognize that the portable lift apparatus  10  can be made out of a different size tubular stock. Doing so adjusts the weight and size handling capabilities of the portable lift apparatus  10 .  
         [0012]    Located at the highest end of the upper boom  20 B in the preferred embodiment, is a pulley wheel  50 , preferably made of steel and three inches in size, together with a bolt  52  to fasten it in place, preferably five-eighths of an inch to one-half inch in size, and a brass sleeve bushing. One of ordinary skill in the art would readily recognize that the size of the pulley wheel  50  and its accessories can vary as can the material that each is constructed from. The pulley wheel  50 , in the preferred embodiment, further has a plate, preferably stainless steel, over the center thereof to protect the pulley wheel  50  and prevent the cable from jumping off of the pulley.  
         [0013]    In the preferred embodiment, steel cable  30  is used to lift and move heavy objects. One of ordinary skill in the art would readily recognize that other types of cable, including but not limited to, aluminum cable can be used on the portable lift apparatus  10 . The cable  30  is wound around a manual or electronic winch  40 . In the preferred embodiment, the cable  30  is then fed parallel along the boom  20 , through a hardened steel cable guide  31 , preferably sized one-half inch by two inches, and located just below the pulley wheel  50 , over the pulley wheel  50  and down through a second cable guide  32 . In the preferred embodiment, the cable guides  31 ,  32  have a one-quarter inch aperture through which the cable  30  is fed. The cable guides  31 ,  32  work to keep the cable  30  centered in the pully; when pulling off-center of the boom  20  during the lifting and moving of heavy objects  64 . In the preferred embodiment, the bottom of the cable guides  31 ,  32  will be chamfered, allowing the cable  30  to move freely in all directions.  
         [0014]    In an alternative, aluminum, embodiment of the portable lift apparatus  10 , a three-fourths inch by one inch solid piece of aluminum with a one-quarter inch chamfered steel guide insert pressed therein will serve to guide the cable  30 .  
         [0015]    The end of the cable  30  preferably has a hook  34  coupled thereto for fastening to and around heavy objects that need to be lifted and/or moved. Although either a manual or an electronic winch  40  can be used with the portable lift apparatus  10 , it is preferred that a twelve volt DC, one ton, free spooling electronic winch be used. One of ordinary skill in the art would readily recognize, however, that a variety of similar electronic winches can be substituted for the electronic winch specified herein. If a manual winch is used, it is preferred that said winch be a free spooling twelve hundred pound manual winch with forward and reverse lock. Again, one of ordinary skill in the art would readily recognize that a variety of similar manual winches can be substituted for the manual winch specified herein.  
         [0016]    In the preferred embodiment, a stabilizing jack  54  is attached to directly to the lower end of the boom  20 A. The stabilizing jack  54  of the preferred embodiment has a crank handle  55  to adjust the height of the stabilizing jack  54 . In the preferred embodiment, a dolly wheel  56  is attached to lowest end of the telescoping leg  55  of the mechanical screw type stabilizing jack  54 . In the preferred embodiment, a dolly wheel  56  is attached to the lowest end of the crank handle  55 . The dolly wheel  56  is used during transportation of the portable lift apparatus  10 . The preferred embodiment further has a support block cover  58 , preferably square in shape, into which the dolly wheel  56  is removably inserted to prevent movement, when extra support is needed during lifting. Both the dolly wheel  56  and the support block cover  58  serve as additional support to the portable lift apparatus  10 .  
         [0017]    [0017]FIG. 3 illustrates a front view of the portable lift apparatus  10 .  
         [0018]    To use the portable lift apparatus  10 , the user simply inserts the male hitch engaging end of the base  22  into the female receiver hitch  62  mounted on any given vehicle  60 . The user then pushes the hitch pin  23  into place and fastens a safety clip. If needed, the user now extends the upper boom  20 B. To do this, the hitch pin  23  is removed and the upper boom  20 B is manually extended. Once the boom  20  is the total length needed, the hitch pin  23  is reinserted through aperture  19  and the nearest aperture  21  to lock the upper boom  20 B in place. The hitch pin  23  is then secured using a safety clip. Now, using a winch  40 , the user can lower or raise the cable  30  and hook  34 . Once the hook  34  is securely fastened on or around the object  64  to be moved, the winch  40  is used to lift said object  64 . The load of the object  64  is supported by the dolly wheel  56  or the support block cover  58 .  
         [0019]    The motor vehicle  60  to which the portable lift apparatus  10  is attached, gives the portable lift apparatus  10  its leverage. Consequently, said motor vehicle  60  should weigh more than the object  64  that the user is lifting or moving.  
         [0020]    Although this invention has certain preferred embodiments, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention, and all such changes and modifications are intended to fall within the true spirit and scope of the invention.