Abstract:
A hand truck comprising an elevating load platform and a carrying frame used to transport heavy and bulky loads on a back of a user. Automated lowering and rising of the platform is accomplished by a threaded rod that runs vertically along a rear spine of the hand truck frame. The rod is connected to an electric motor operated by a small rechargeable battery carried on board. A shoulder harness is provided directly below a handle assembly enabling the user to place the loaded hand truck on their shoulders. Activation of the raised platform elevates the load to the shoulder area where it can be carried more comfortably and safely.

Description:
RELATED APPLICATIONS 
     The present invention was first described in and claims the benefit of U.S. Provisional Application No. 61/345,319 filed May 17, 2010, the entire disclosure of which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to a hand truck, and in particular, to a hand truck with a shoulder-mounted carrying means and motorized lifting mechanism. 
     BACKGROUND OF THE INVENTION 
     Hand trucks are one of the most commonly utilized pieces of equipment for manual transportation of small, heavy items over short distances. Such devices are commonly utilized for delivery and stocking operations, such as transporting boxes of products from a truck to a delivery point or for transporting quantities of merchandise from a storage area to a retail shelf for stocking. 
     One (1) common concern with hand trucks is that their narrow platform results in vertical stacking of objects during transport. When the objects are unloaded at the delivery point, they are removed from the top down. As the last remaining boxes or objects are removed from the hand truck, the user is forced to bend over nearly to the floor, which poses safety and health concerns. 
     Another common problem with hand trucks is that, while they are very efficient for moving objects across flat ground surfaces with minimal strain, it is very difficult to navigate even minor vertical obstructions such as stairways or even single steps in the entranceway of a building. This generally forces the user to either get help, lift the entire hand truck and load over the obstruction, or manually transport the objects beyond the point of the obstruction. 
     Various attempts have been made to provide mechanically or electrically assisted hand trucks adapted to help a user lift the laden hand truck during use. Examples of these attempts can be seen by reference to several U.S. patents. U.S. Pat. No. 4,057,119, issued in the name of Melson, describes a powered hand truck adapted to help a user climb stairs. U.S. Pat. No. 5,829,763, issued in the name of Jeavons, describes an attachable elevating unit for hand trucks which provides assisted lifting of the entire hand truck against a ground surface. U.S. Pat. No. 6,398,477, issued in the name of Fox, discloses an electric hand truck with motorized lift capabilities for raising or lowering objects from loading docks, trucks, or the like. 
     While these apparatuses fulfill their respective, particular objectives, each of these references suffer from one (1) or more of the aforementioned disadvantages. Many such apparatuses are very slow to operate. Also, many such apparatuses help to navigate the hand truck over stairs and the like but do not assist in unloading objects on the hand truck in an elevated manner. Furthermore, many such apparatuses are not adapted to navigate vertical obstructions. In addition, many such objects are slow to operate and unnecessarily complex when, for instance, the user desires to quickly navigate a single step while entering a building. Accordingly, there exists a need for a hand truck without the disadvantages as described above. The development of the present invention substantially departs from the conventional solutions and in doing so fulfills this need. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing references, the inventor recognized the aforementioned inherent problems and observed that there is a need for a hand truck with powered lifting assistance which can quickly and simply navigate vertical obstructions. Thus, the object of the present invention is to solve the aforementioned disadvantages and provide for this need. 
     To achieve the above objectives, it is an object of the present invention to provide assistance in transporting a load on a pair of wheels while angled towards a user, in a manner similar to a common hand truck. 
     Another object of the present invention is to enable the user to quickly navigate vertical obstructions in a ground surface by providing first and second shoulder braces that allow the user to securely brace the apparatus against their back. In this manner, the user can quickly manually lift the hand truck and load and navigate a step, stairway, or similar obstruction. Each shoulder brace includes a shoulder pad to cushion the user&#39;s shoulders during use and a strap to secure the shoulder brace to the user. 
     Yet still another object of the present invention is to provide digit openings within each shoulder brace allowing the user to grip and wheel the apparatus in a common manner when on a level ground surface. 
     Yet still another object of the present invention is to provide a pair of ergonomic handles located midway down the sides of the apparatus at arm&#39;s length and oriented forward. The ergonomic handles provide a secure and stabilizing grip for the user when transporting the apparatus using the shoulder braces. 
     Yet still another object of the present invention is to provide a motorized lifting mechanism allowing the user to raise or lower a retractable portion of the apparatus in an assisted manner. Vertical positioning of the load can be utilized to position the load for ease of loading or unloading as well as to provide a desired distribution of weight prior to carrying the apparatus on the user&#39;s shoulders. 
     Yet still another object of the present invention is to guide the retractable lower portion of the apparatus within a stationary upper portion with a pair of channel members in the retractable portion that engage a pair of tracks within the stationary portion. 
     Yet still another object of the present invention is to provide a motor that rotates a lead screw connected to the stationary portion. The lead screw engages a threaded nut attached to the retractable portion such that rotation of the lead screw motions the retractable portion including a platform for holding the load. 
     Yet still another object of the present invention is to provide an activation switch located on one of the ergonomic handles allowing the user to operate the motor while carrying the apparatus on their shoulders. 
     Yet still another object of the present invention is to provide an additional vertically adjustable platform removably attached above the stationary platform to provide additional support, storage, and bifurcation of the load. 
     Yet still another object of the present invention is to provide a method of utilizing the device that provides a unique means of acquiring the apparatus, positioning a load on the adjustable platform and stationary platform, resting each shoulder pad on the shoulder region of the user, depressing the activation switch to operate the motor, transporting the load to a desired location, lifting and moving loads up and down steps or around obstructions. Another alternately engaging the digit openings and transporting the apparatus to a desired location with the wheels, and, utilizing the apparatus in a conventional manner. 
     Further objects and advantages of the present invention will become apparent from a consideration of the drawings and ensuing description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The advantages and features of the present disclosure 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: 
         FIG. 1  is an environmental view of a shoulder-mounted hand truck  10 , according to a preferred embodiment of the present invention; 
         FIG. 2  is a side perspective view of the shoulder-mounted hand truck  10 , according to a preferred embodiment of the present invention; 
         FIG. 3  is an opposing side perspective view of the shoulder-mounted hand truck  10 , according to a preferred embodiment of the present invention; 
         FIG. 4  is an exploded perspective view of the shoulder-mounted hand truck  10 , according to a preferred embodiment of the present invention; and, 
         FIG. 5  is an electrical block diagram of the shoulder-mounted hand truck  10 , according to a preferred embodiment of the present invention. 
     
    
    
     DESCRIPTIVE KEY 
     
         
         
           
               10  shoulder-mounted hand truck 
               15  user 
               16  load 
               20  stationary portion 
               21  first track 
               22  second track 
               23  first brace 
               24  second brace 
               25  third brace 
               26  motor 
               27  lead screw 
               28  coupler 
               29  guard 
               30  electrical wire 
               31  first shoulder brace 
               32  first shoulder pad 
               33  first strap 
               34  digit opening 
               35  second shoulder brace 
               36  second shoulder pad 
               37  second strap 
               38   a  first handle 
               38   b  second handle 
               39  activation switch 
               40  retractable portion 
               41  first channel member 
               42  second channel member 
               43  nut 
               44  tube 
               45  adjustable platform 
               46  platform attachment 
               47  projection 
               48  stationary platform 
               49  wheel 
               50  wheel attachment 
               51  battery 
           
         
       
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In accordance with the invention, the best mode is presented in terms of a preferred embodiment, herein depicted within  FIGS. 1 through 5 . However, the disclosure is not limited to a single described embodiment and a person skilled in the art will appreciate that many other embodiments are possible without deviating from the basic concept of the disclosure and that any such work around will also fall under its scope. It is envisioned that other styles and configurations can be easily incorporated into the teachings of the present disclosure, and only one particular configuration may be shown and described for purposes of clarity and disclosure and not by way of limitation of scope. 
     The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items. 
     The present invention describes a shoulder-mounted hand truck (herein described as the “apparatus”)  10 , comprising a common hand truck frame including enhanced shoulder-mounting and automated features to enable a user  15  to transport the apparatus  10  upon their shoulder region. A load  16  is positioned onto the apparatus  10  in a conventional upright manner which may be electrically and mechanically lifted to distribute the weight of the load  16  evenly upon the user&#39;s  15  back. The apparatus  10  is also utilized in a conventional manner which enables the user  15  to transport the load  16  which is angled toward said user  15  for subsequent transfer to a desired location via a pair of wheels  49 . 
     Referring now to  FIG. 1 , an environmental view of the apparatus  10 , according to the preferred embodiment of the present invention, is disclosed. The apparatus  10  comprises a stationary portion  20  and a retractable portion  40 . The stationary portion  20  is located on an upper portion of the apparatus  10  and the retractable portion  40  is adjustably attached below the stationary portion  20 . Each portion  20 ,  40  is arranged in a vertical position with respect to an upright user  15 . The stationary portion  20  comprises a first track  21 , a second track  22 , a motor  26 , a lead screw  27 , a first shoulder brace  31 , and a second shoulder brace  35 . The retractable portion  40  comprises a first channel member  41 , a second channel member  42 , a tube  44 , an adjustable platform  45 , and a stationary platform  48 . The apparatus  10  is fabricated from materials such as, but not limited to: aluminum, wood, plastic, or the like. 
     Referring now to  FIG. 2 , a side perspective view of the apparatus  10 ,  FIG. 3 , an opposing side perspective view of the apparatus  10 , and  FIG. 4 , an exploded perspective view of the apparatus  10 , according to the preferred embodiment of the present invention, are disclosed. The stationary portion  20  comprises a first track  21  and a second track  22  in a parallel orientation. The tracks  21 ,  22  are “C”-shaped which enables a first channel member  41  and a second channel member  42  to travel within said tracks  21 ,  22 , respectively (see herein below). The tracks  21 ,  22  are equally spaced and secured via a first brace  23  and a second brace  24  which are positioned in a horizontal orientation at an upper location of the stationary portion  20 . The distance between the first brace  23  and the second brace  24  enables ample space for placement of a motor  26 . The shaft of the motor  26  is positioned in a downward manner to enable a coupler  28  to interconnect the motor shaft to the lead screw  27 . The coupler  28  is fixed to the second brace  24 . The motor  26  preferably comprises a rechargeable DC battery  51  (also see  FIG. 5 ), yet other devices may be utilized without limiting the scope of the apparatus  10 . The lead screw  27  is a shaft comprising an exterior surface which is threaded. The lead screw  27  is located at in intermediation position between the second brace  24  and a third brace  25  and the tracks  21 ,  22 . A “T”-shaped guard  29  is positioned in front of the lead screw  27  which provides protection to the user&#39;s  15  back while in use. The guard  29  is attached to the rear portion of the stationary portion  20  via means such as, but not limited to: welding, nuts and bolts, or the like. 
     The rear portion of the stationary portion  20  also comprises a means for the user  15  to handle the apparatus  10 . An upper rear portion of the stationary portion  20  comprises a first shoulder brace  31  and a second shoulder brace  35 . The first shoulder brace  31  is attached to the first track  21  and the second shoulder brace  35  is attached to the second track  22 , each oriented forwardly. Each shoulder brace  31 ,  35  is attached perpendicular to its respective track  21 ,  22  via means such as, but not limited to: welding, nuts and bolts, or the like. The first shoulder brace  31  comprises a first shoulder pad  32  and the second shoulder brace  35  comprises a second shoulder pad  36 , each of which provide a comforting cushioning means to the user  15  during use. The shoulder pads  32 ,  36  are fabricated from a foam rubber material, yet other materials may be utilized without limiting the scope of the apparatus  10 . Each shoulder pad  32 ,  36  comprises a digit opening  34  which provides a gripping means to the apparatus  10  which enables the apparatus  10  to be utilized in a conventional transporting manner which requires the user  15  to push or pull the apparatus  10  along a level surface via a pair of wheels  49  (see herein below). The first shoulder brace  31  also comprises a first strap  33  and the second shoulder brace  35  also comprises a second strap  37 , each of which provide a securing means to the user  15 . The straps  33 ,  37  are fabricated from a padded fabric and are also attached to a respective track  21 ,  22  via common fastening means. 
     The stationary portion  20  also comprises a pair of ergonomic handles  38   a ,  38   b  which provide the user  15  with a means to stabilize the apparatus  10  during use. The handles  38   a ,  38   b  are positioned on a rear lower surface of the stationary portion  20  at arms length and oriented forwardly. The second handle  38   b  preferably comprises an activation switch  39  which activates the motor  26  to motion in a forward or reverse direction. The second handle  38   b  is depicted herein as comprising the activation switch  39  for illustration purposes only it is known that other locations may be utilized without limiting the scope of the apparatus  10 . The activation switch  39  is comprised of a conventional dual positional pushbutton, yet other electrical switches may be utilized without limiting the scope of the apparatus  10 . Each handle  38   a ,  38   b  is attached to the rear surface of the tracks  21 ,  22  via means such as, but not limited to: welding, nuts and bolts, or the like. 
     The retractable portion  40  comprises a first channel member  41  and a second channel member  42  which engage the first track  21  and second track  22 , respectively to enable said retractable portion  40  to be retracted or extended. Each channel member  41 ,  42  comprises a rectangular-shape which enables each to slidably engage the respective tracks  21 ,  22 . Secured perpendicularly to an inner portion of the channels  41 ,  42  is the third brace  25  which also provides a guidance means to the lead screw  27  via an internally threaded nut  43 . The threads upon the lead screw  27  engages the threads upon the nut  43  to pull or push the retractable portion upwardly or downwardly and concurrently enabling the tracks  21 ,  22  to engage the respective channels  41 ,  42 . The nut  43  is fixed to an upper surface of a third brace  25  and is utilized to direct and guard the lead screw  27  through said nut  43  and into a tube  44 . The lead screw  27  descends into the tube  44  when the apparatus  10  is retracted. The tube  44  is slightly larger in diameter than the lead screw  27  which enables the tube  44  to accept the lead screw  27 . The tube  44  is attached to a lower horizontal member of the retractable portion  40  via common attachment means. 
     A front lower portion of the retractable portion  40  also comprises a stationary platform  48  which provides a level surface to position a load  16 . The stationary platform is positioned perpendicular to the channel members  41 ,  42 . A rear lower portion of the retractable portion  40  comprises a pair of wheels  49  which provide a conventional transporting means to the apparatus  10 . The wheels  49  are attached to a wheel attachment  50  which enables said wheels  49  to rotate and transport the apparatus  10  to a desired location as determined by the user  15  directing said apparatus  10  via grasping the digit openings  34 . 
     The apparatus  10  also comprises an adjustable platform  45  providing a height adjustable level surface to position an additional load  16 . The adjustable platform  46  comprises an “L”-shape which enables a vertical platform attachment  46  to attach to a desired projection  47 . A plurality of projections  47  is located in series along the side surfaces of the tracks  21 ,  22 . The projections  47  are comprised of bolts, yet other means may be utilized without limiting the scope of the apparatus  10 . Each platform attachment  46  slidably engages and locks onto a desired projection  47  which stabilizes the adjustable platform  45  against the tracks  21 ,  22 . 
     Referring now to  FIG. 5 , an electrical block diagram depicting the major electrical components of the apparatus  10 , according to the preferred embodiment of the present invention, is disclosed. Current is supplied to the activation switch  39  and the motor  26  via the battery  51 . With the battery  51  fully charged, the activation switch  39  may be depressed to a desired orientation to activate the motor  26  in a clockwise or counterclockwise direction which concurrently rotates the lead screw  27  to move the apparatus  10  downwardly or upwardly, respectively. The battery  51  is preferably located within the motor  26  and is interconnected to the activation switch  39  and the motor  26  via appropriately gauged electrical wiring  30 . 
     It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope. 
     The preferred embodiment of the present invention can be utilized by the common user in a simple and effortless manner with little or no training. After initial purchase or acquisition of the apparatus  10 , it would be installed as indicated in  FIG. 1 . 
     The method of utilizing the apparatus  10  may be achieved by performing the following steps: acquiring the apparatus  10 ; positioning the apparatus  10  onto a level surface with each wheel  49  superjacently engaging the level surface; positioning the adjustable platform  45  to a desired height via engaging each platform attachment  46  with a desired projection  47 ; positioning a desired load  16  onto the adjustable platform  45  and stationary platform  48 ; arranging the user&#39;s  15  arms through each strap  33 ,  37  and resting each shoulder pad  32 ,  36  upon the shoulder region of the user  15 ; depressing the activation switch  39  on the first handle  38   a  to engage the motor  26  which rotates the lead screw  27  and concurrently ascends the retractable portion  40  into the stationary portion  20 ; releasing the activation switch  39  when a desired height is reached; transporting the load  16  to a desired location; lifting upwardly upon the handles  38   a ,  38   b  to support the load  16  as necessary; depressing the activation switch  39  to descend the retractable portion  40 ; removing the apparatus  10  from the user&#39;s  15  shoulder region; unloading the apparatus  10  in a conventional manner; and, lifting and moving loads  16  up and down steps, around obstructions, and load them in a manner that reduces back strain. 
     Another method of utilizing the apparatus  10  may be achieved in a conventional manner by performing the following steps: acquiring the apparatus  10 ; positioning the apparatus  10  onto a level surface with each wheel  49  superjacent to the level surface; positioning the adjustable platform  45  to a desired height via engaging each platform attachment  46  with a desired projection  47 ; positioning a desired load  16  onto the adjustable platform  45  and stationary platform  48 ; enabling the user  15  to engage the digit opening  34  with their hands; positioning the apparatus  10  at an angle toward the user  15  and supporting the load  16  with the user&#39;s  15  arms; transporting the apparatus  10  to a desired location via the wheels  49 ; positioning the apparatus  10  to an original vertical position; and, utilizing the apparatus  10  in a conventional manner. 
     The foregoing descriptions of specific embodiments have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention and method of use to the precise forms disclosed. Various modifications and variations can be appreciated by one skilled in the art in light of the above teachings. The embodiments have been chosen and described in order to best explain the principles and practical application in accordance with the invention to enable those skilled in the art to best utilize the various embodiments with expected modifications as are suited to the particular use contemplated. It is understood that various omissions or substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but is intended to cover the application or implementation without departing from the spirit or scope of the claims of the invention.