Abstract:
A vehicle-mounted cargo lift including a frame and carry arms suitable for carrying a scooter, a personal transportation device, or other cargo. The frame includes a power inverter/converter, which provides power to a motorized worm drive, which raises and lowers the carry arms. Wheel chocks on the carry arms hold in place the scooter wheels. The cargo lift attaches to the back of a vehicle via a trailer hitch.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   Priority is hereby claimed to provisional application Ser. No. 60/819,774, filed Jul. 10, 2006, which is incorporated herein by reference. 

   FIELD OF INVENTION 
   This invention relates generally to an apparatus for transporting personal mobility devices and, more specifically to an apparatus for transporting two-wheeled mobility devices on the back of a vehicle. 
   DESCRIPTION OF THE PRIOR ART 
   The need to transport large or odd sized cargo has presented a conundrum for the average owner of a vehicle. A cargo item that is too large to fit inside the cabin of the car or in the trunk generally must be carried on the outside of the vehicle. The prior art is filled with examples of flat bed trailers, roof racks, luggage racks and plenty of commercial rentals available for single or sporadic usage. However, for those that must carry a single large item on a daily basis, an efficient and convenient transportation device is essential. 
   Users of a personal mobility device such as a scooter or wheelchair have several options for vehicle-based transportation. Generally, these prior art apparatuses provide a platform, or flat structure, on which the conventionally four wheeled device is loaded. Because of the weight of power scooters, a suitable transportation device is often bulky and generally must include a ramp or other cumbersome loading device. 
   As technology has developed, so has the selection of personal mobility devices. The gyroscopically-operated Segway®-brand human transporter has become a very popular option. Segway®-brand human transporter is a registered trademark of Segway, Inc., a Delaware corporation whose corporate office is in Bedford, N.H. Segway®-brand human transporters have two wheels and are not suitable for transportation using a conventional prior art transport apparatus. Therefore, a need exists for an apparatus to efficiently load and transport a two-wheeled scooter device in a convenient and secure manner. 
   SUMMARY 
   The present invention is a cargo lift comprising a frame, at least one carry arm, at least one wheel chock, a lift mechanism, at least one locking arm, a mounting arm, a height-adjusting mechanism, and a power inverter/converter. The carry arm is attached to the frame and is rotatably movable from a first position substantially parallel to the frame to a second position substantially perpendicular to the frame. When the carry arm is in the second position, the wheel chock is located on the carry arm at a position distal from the frame. The lift mechanism is operationally linked to the frame and dimensioned and configured to translate the carry arm from a first loading position to a second towing position. The lift mechanism comprises a worm drive disposed substantially parallel to the frame and wherein a first end of the worm drive is operationally linked to the carry arm. The worm drive is also dimensioned and configured so that when the worm drive is rotated, the carry arm is translated from the first loading position to the second towing position. The locking arm comprises a proximal end and a distal end, and is connected to the frame at its proximal end. The distal end extends perpendicularly outward from the frame and extends over the carry arm. The locking arm further comprises a bumper on the distal end. The mounting arm is attached to the frame and dimensioned and configured to matingly engage a towing vehicle. The height-adjusting mechanism is fixed to the mounting arm and the frame, and is dimensioned and configured to raise or lower the frame in relation to the towing vehicle. The power inverter/converter is attached to the frame and is dimensioned and configured to provide power to the cargo carried on the lift. The power inverter/converter further comprises a power cord. 
   The present invention is further directed to a cargo lift comprising a frame, at least carry arm, at least one wheel chock, a lift mechanism, at least one locking arm, a mounting arm, a height-adjusting mechanism, and a power supply conduit. The power supply conduit is attached to the frame and is dimensioned and configured to provide power to the cargo carried on the lift. The power supply conduit further comprises a power cord. The lift mechanism comprises a worm drive disposed substantially parallel to the frame. A first end of the worm drive is operationally linked to the carry arm and when the worm drive is rotated, the carry arm is translated from the first loading position to the second towing position. The worm drive can be operated either manually or via an electric motor. The electric motor is operationally connected to the power supply conduit. 
   The present invention is a cargo lift, which allows a user to easily secure and transport a two-wheeled scooter on the back of their vehicle. The lift connects with a conventional trailer hitch mounting socket. The lift also includes a height adjusting mechanism positioned between the mounting arm and the frame, which allows the entire lift to raise and lower relative to the ground. This is distinctly advantageous because it allows the lift to be used on vehicles with a high ground clearance or a low ground clearance. 
   After the lift has been properly attached to the back of the vehicle, the two carry arms are released from the stowed position and folded into the locked towing position, parallel to the ground. The carry arms are connected to the lower end of the frame. In order to easily load the two-wheeled scooter onto the lift, the carry arms must be lowered to rest on the ground. This is achieved by a worm gear located within the frame, and is operated by an electric motor, or a manual hand crank. The electric motor is powered by a power inverter/converter attached to the frame. The user simply turns on the motor, which rotates the worm gear, which in turn lowers the end of the frame and puts the carry arms onto the ground. 
   With the carry arms stably placed on the ground, the user must only roll the two-wheeled scooter onto the carry arms. The scooter wheels securely rest between sets of chocks attached to the carry arms. The chocks prevent the wheels from rolling forward or backwards while in motion. 
   The scooter is secured to the frame of the lift by two locking arms. The locking arms are rotatably connected to the frame and attached to the scooter. The locking arms are secured in place by lynch pins, thus securely hold the scooter on the lift. After the scooter is securely fastened to the lift, the carry arms are raised to a suitable height above the ground. This is accomplished again by the worm drive. The scooter is now secured to the back of a user&#39;s vehicle and can be transported safely and securely. 
   Another advantage of the present invention is the ability to charge the cargo while it is being towed. The power inverter/converter has a power cord into which the cargo can connect. The present invention attaches to the vehicle&#39;s electrical system through a standard round seven-prong (RV style) trailer electric plug. This feature allows the present invention to be easily adaptable to include lights or other electrical systems. 
   The objects and advantages of the invention will appear more fully from the following detailed description of the preferred embodiment of the invention made in conjunction with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective of the cargo lift with the carry arms in the fully lowered position. 
       FIG. 2  is a side elevation of the cargo lift with the carry arms in the fully raised position. 
       FIG. 3  is a side elevation of the frame, the height-adjusting mechanism and the locking arms. 
       FIG. 4  illustrates the cargo lift removed from a towing vehicle and in a folded and compact position. 
       FIG. 5  is side elevation of the cargo lift mounted to a towing vehicle, with the carrying arms folded in a position parallel to the frame. 
       FIG. 6  is a side plan view of the cargo lift with a personal transporter secured on the carry arms and raised to the towing position. 
       FIG. 7  is an illustration of a worm gear. 
   

   DETAILED DESCRIPTION 
   Reference will now be made to the attached drawings, where the same reference numerals are used throughout the various views. 
   Referring to  FIGS. 1-7 , where the same reference numerals are used throughout the drawings, the invention is a cargo lift  10 . As shown in the figures, the lift  10  is dimensioned and configured to lift, and to lock into place, a Segway®-brand human transporter (hereinafter generically referred to as a scooter,  100 ) for transport by a conventional trailer hitch receiver attached to a motor vehicle. (“Segway” is a registered trademark of Segway, Inc., a Delaware corporation whose corporate office is in Bedford, N.H.) For purposes of brevity only, the following description is limited to a lift  10  dimensioned and configured to carry such a scooter  100 . However, the invention explicitly encompasses lift designs having the same claimed elements that are specifically dimensioned to carry other types of cargo. 
   The cargo lift  10  includes a vertically-oriented, telescoping frame  12 , with spaced carry arms  14  attached to the frame. The carry arms  14  are preferably oriented so that they extend parallel to the direction of travel of the towing vehicle. The carry arms  14  are pivotally attached, at their proximal ends, to the frame; the distal ends of the carry arms  14  rotate around the axis created by the proximal ends. In the preferred embodiment, the distal ends of the carry arms  14  have a freedom of movement of about 90 degrees: from substantially perpendicular to the frame  12  (substantially parallel to the ground) to substantially parallel to the frame  12  (substantially perpendicular to the frame.) Wheel chocks  15  are provided on the carry arms  14  to cradle the wheels of the scooter  100  (see  FIG. 6 ). In the preferred embodiment, the wheel chocks  15  are present in two places, extending laterally, on each of the two carry arms  14 , as shown in  FIG. 1 . However, the wheel chocks  15  can also extend medially between the carry arms  14  so that the wheels of the scooter  100  rest between the carry arms  14 . In another embodiment, the cargo lift  10  can have a single carry arm  14  with wheel chocks  15  that extend from the carry arm  14  sufficiently enough to support the wheels of the scooter  100 . 
   In the preferred embodiment, the cargo lift  10  also includes at least one locking arm  18  connected at its proximal end to the frame  12 . The locking arm  18  includes a bumper  19 , attached to its distal end, which functions to engage the cargo firmly, but resiliently, so as not to damage the surface of the cargo. See especially  FIG. 3 , which depicts a scooter  100 , resting upon the lift  10 , with the lift in the raised position. As shown in  FIG. 3 , with the lift  10  in the raised position, the locking are  18  firmly engaging the deck of the scooter  100 , thereby securely locking the scooter onto the lift  12 . This prevents the scooter  100  from falling off of the lift  12  during transport, and also prevents theft of scooter  100  when the transporting vehicle is parked or otherwise left unattended. 
   A lift mechanism  16  (preferably a worm drive or screw drive as illustrated in  FIG. 7 ) is operationally connected to the frame  12  so that the lift arms can be moved from a lowered position (resting on the ground) as shown in  FIG. 1 , to a raised position, as shown in  FIGS. 2 and 6 . The preferred lift mechanism  16 , with a worm drive  17 , can be either manually operated or activated with an electric motor. The worm drive  17  is dimensioned and configured so that a worm gear  27  is located within the frame  12 , and is positioned in axial register with frame  12 . When the worm gear  27  rotates, the carry arms  14  are moved in a direction parallel to the frame  12 . The worm gear  27  can be rotated either by a manual hand-crank  37 , an electric motor  47 , or another powered source. The lift mechanism houses the hand-crank  37  and electric motor  47 . 
   Continuing with  FIG. 3 , the lift  12  includes a mounting arm  24  that is preferably dimensioned and configured to matingly engage with a conventional trailer hitch receiver on a towing vehicle. A height-adjusting mechanism  26  is provided to raise or lower the mounting height of the entire frame  12  via a series of horizontally-oriented apertures. See also  FIG. 4 . The height-adjusting mechanism  26  is located between the frame  12  and the mounting arm  24  and allows the lift  12  to be attached on vehicles that have differing ground clearances (e.g., a four-wheel drive pick-up truck versus a sedan) while ensuring that the lift arms  14  will contact the ground when in the lowered position as shown in  FIG. 1 . The height-adjusting mechanism  26  is secured to the mounting arm  24  preferably with two removable lynch pins inserted through the horizontally-oriented apertures. 
   In the preferred embodiment as shown in  FIG. 3 , the lift includes a power inverter/converter  20 , and a corresponding charging cord  22 . As shown in the figures, the inverter/converter  20  and cord  22  are dimensioned and configured to charge a Segway®-brand human transporter. The inverter/converter  20  and cord  22  may be dimensioned and configured to provide power to whatever type of cargo is placed upon the lift  10  without limitation (e.g., a different type of scooter, a refrigeration unit, a heater, a lighting unit, etc.) 
   As shown in  FIG. 5 , a particularly advantageous aspect of the invention is that the lift mechanism  16  and the inverter/converter  20  are both powered by a conventional trailer electrical socket  50 . In  FIG. 5 , the socket  50  is shown as the preferred 7-pin wiring harness that is standard equipment in the United States and many other countries. Other wiring harness types may also be used. In yet another embodiment, the lift mechanism  16  and the inverter/converter  20  may be powered by a battery. 
   When not in use, the lift  10  may be removed from the vehicle and folded flat, as shown in  FIG. 4 . The lift  10  may also remain on the vehicle, and can be folded in place so that it rests flush with the back surface of the vehicle, as shown in  FIG. 5 . When folded, the carry arms  14  and the locking arms  18  pivot about their attachment points to the frame  12  so that both the carry arms  14  and the locking arms  18  are situated substantially in the same plane as the frame  12 . This makes the lift extremely compact when not in use. 
     FIGS. 3 and 6  show the lift  10  with a Segway®-brand human transporter  100  disposed on the lift, with the lift in the raised position. The locking arms  18  engage the human transporter and securely grip it between the locking arms  18  and the carry arms  14 . In the raised position, the human transporter  100  cannot be removed from the lift, short of damaging the lift, the human transporter, or both. The wheels of the human transport rest upon the chocks  15 , thereby providing for secure transport of the transporter without worry of damaging it. Also, because the transporter is carried behind the vehicle, it does not gather bugs or other road debris. The inverter  20  can be operationally connected to the human transporter  100  via the cord  22 . In this fashion, when the user arrives at his destination, the transporter is fully charged and ready for use.