Abstract:
An apparatus is provided to enable a personal transportation vehicle, such a motorcycle, to turn up to 180 degrees around while remaining in a confined, compact space. The apparatus comprises a lightweight inner platform rotating inside a lightweight, fixed, outer platform and uses translated power from the personal transportation vehicle as a motive force to turn the vehicle.

Description:
RELATED APPLICATIONS 
     This application claims priority from U.S. Provisional application 61/144,475 filed Jan. 14, 2009. 
    
    
     FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     REFERENCED OR INCORPORATED MATERIAL 
     Not applicable. 
     FIELD OF INVENTION 
     The present invention relates to the field of compact personal transportation vehicle storage. More specifically, the invention is a portable vehicle turntable that allows the operator of a personal transportation vehicle to drive onto the turntable and have the vehicle reverse direction via the motive power of the vehicle in a limit space environment. 
     SUMMARY OF THE INVENTION 
     The present invention is an apparatus that enables a personal transportation vehicle, such a motorcycle, to turn up to 180 degrees around while remaining in a confined, compact space. Moreover, the apparatus requires no independent or internal power source as the apparatus is operated via motive power supplied by the vehicle. The apparatus may fit in tight spaces such as garages and may be beneficial when space for turning a vehicle around is limited. Also, as many personal transportation vehicles lack a reverse gear, the apparatus enables the operator to turn the vehicle around and drive in the intended forward direction where she would not otherwise be able to do so. 
     Such features may afford many safety advantages as well. For instance, the apparatus may afford the ability to turn a vehicle around to exit on a busy street, rather than back out thereby offering improved personal safety. 
     As noted above, the apparatus requires no internal power source and no independent, third party, power source. Rather, the motive power is applied to the apparatus from the vehicle via the powered wheels of the vehicle. In the case of the motorcycle, this powered wheel is the rear wheel. The operator of the vehicle drives the vehicle onto the platform. The powered wheel(s) of the vehicle contacts a pair of shafts which are geared to rotate the platform until the operator ceases to apply power to the wheel(s) and the apparatus ceases to turn. Though the preferred embodiment is described with contemplation of use with motorcycles, the invention may be altered to suit other similar vehicles. 
     The apparatus functions as a turntable with two platforms, an inner platform and an outer platform. The outer platform is fixed and the inner platform rotates about a center point of the two platforms and is supported by ball bearings. The inner platform provides a surface upon which the vehicle rests and an opening for the wheel of the vehicle to contact the shafts which turn the inner platform. 
     The platform is designed to be lightweight and portable. In alternate embodiments, the platform has castors or other such wheels attached which may be raised or lowered for easy mobility. Also in alternate embodiments, the apparatus has a wall mounted connector to allow the platform to be lifted from the floor to a position against a wall while not in use. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIG. 1  is an exploded view of the apparatus. 
         FIG. 2  is a cutaway view of the apparatus showing a motorcycle positioned on the inner platform with the tire touching the shafts. 
         FIG. 3A  is a top view of the apparatus in the initial rest position where the motorcycle has entered the apparatus. 
         FIG. 3B  is a top view of the apparatus in the 90 degree rotated position. 
         FIG. 3C  is a top view of the apparatus in the 180 degree rotated position. 
         FIG. 3D  is a top view of the apparatus in the 180 degree rotated position where the motorcycle has exited the apparatus. 
     
    
    
     DETAILED DESCRIPTION 
     It is to be understood by a person having ordinary skill in the art that the present discussion is a description of exemplary embodiments only and is not intended as limiting the broader aspects of the present invention. The following example is provided to further illustrate the invention and is not to be construed to unduly limit the scope of the invention. 
     The present invention is designed to allow a vehicle such as a motorcycle to do a 180 degree turn in a confined space such as a garage or a driveway. The invention is an apparatus that facilitates this stationary U-turn and comprises an inner and an outer platform. The outer platform operates in a fixed position and rests on the floor of the garage, driveway, or on the ground as the case may be. The apparatus operates from a rest position to a loaded position. The loaded position is that position where the motorcycle is on top of the inner platform and the rest position is that position where the motorcycle is off of the inner platform and the inner platform has rotated such that the shafts are nearest the entrance point of the motorcycle. The loaded position further comprises several sub positions as can be seen in  FIG. 3A ,  FIG. 3B ,  FIG. 3C , and  FIG. 3D . In these sub positions, the motorcycle has driven onto the inner platform. In  FIG. 3A , the tires of the motorcycle have just contacted the shafts. In  FIG. 3B  the tires of the motorcycle have begun to drive the shafts and the platform has rotated about 90 degrees. In  FIG. 3C  the tires have continued to drive the shafts and the platform has rotated a further 90 degrees. In  FIG. 3D  the motorcycle is exiting the platform having been rotated 180 degrees from the point it entered the platform in the rest position. 
     The outer platform may be rectangular or round and is shown in the drawings as rectangular. The outer platform has a bottom, preferably made of sheet metal, and a top, preferably made out of plastic. The outer edges of the platform are sloped upward towards the center of the platform to facilitate driving onto the apparatus by a vehicle. The bottom is mostly flat but has a series of indentations within which to hold/cradle ball bearings. In one embodiment, these indentations are circular about the center of the platform forming concentric circles. However, the indentations might also use some other pattern or random placement. 
     The top of the outer platform has a large circular opening within which the inner platform operates. The top also has a circular gear at the outer edge of the circular opening. This circular gear meshes with a drive shaft gear from the inner platform. There is also a recoil device fixed in the center of the bottom of the outer platform that is attached to the center point of the inner platform as well. This recoil device operates to return the inner platform to its original rest position after the vehicle has exited the apparatus. 
     The inner platform is circular and fits within the circular opening of the outer platform. Like the outer platform, the inner platform has a bottom, preferably made from sheet metal and a top portion made from plastic. The metal of the bottom of the inner platform provides a smooth surface that comes into contact with the ball bearings of the outer platform and facilitates the rotation of the inner platform within the outer platform. Within the inner platform, and rotatably attached thereto, are a pair of drive shafts. Each of these drive shafts has a drive gear attached to one end. These drive shafts roughly span a cord of the circular inner platform and are disposed such that the respective drive gears are at opposite ends of the cord. These drive gears come into contact with the large circular gear of the outer platform. Each of the respective shafts is held in place by a pair of displaced ball bearing casements with the ball bearing casements being fixedly attached to the inner platform. 
     Disposed on the top surface of the inner platform is an opening, preferably rectangular in shape, which allows access to a central portion of the drive shafts from the top of the apparatus. This opening allows the tires of the motorcycle to contact the shafts. When the tire contacts the drive shafts and the operator of the motorcycle applies power to the wheels, the tires turn and translate power to the drive shafts. As the drive shafts rotate, the drive gears likewise turn and mesh with the large circular gear of the outer platform. This movement results in the rotation of the inner platform. 
     As noted above, the recoil device is fixed to the center of the outer platform and is also attached to the center of the inner platform. The function of the recoil is to return the apparatus from the final loaded position where the rectangular opening in the inner platform is furthest from the point where the motorcycle first drives onto the apparatus to the rest position where the rectangular opening in the inner platform is closest to the point where the motorcycle first drives onto the apparatus. As the motorcycle translates power to the apparatus facilitating the turn, the recoil builds up some recoil spring energy. When the motorcycle exits the apparatus, a trigger is released that unloads the recoil spring energy. This unloading provides energy that returns the motorcycle to the rest position. This trigger that releases the recoil may be a manual trigger required to be actuated by the operator of the motorcycle. The trigger may be a switch that is automatically actuated by the motorcycle when exiting the apparatus. The trigger may also be actuated by the decreased weight on the apparatus after the motorcycle exits. In each of these cases, when the motorcycle exits, the recoil operates to return the apparatus to the rest position. 
     In alternate embodiments, a set of fixable castors are located on the outer edges of the outer platform. These castors may be fixed to prevent movement when the apparatus is in use. Likewise, the castors may be placed into an operable position when the operator desires to move the apparatus. 
     In still another alternate embodiment, the invention includes a wall mounted connector that allows the apparatus to be lifted from the floor or ground to a wall for storage when not in use.