Abstract:
A pedal-powered one-wheeled vehicle with apparatus coupled to the pedals for laterally stabilizing a user&#39;s legs. The user can apply inward pressure to the leg stabilizing apparatuses to achieve greater lateral stability and more precise control of the vehicle. Means may be provided for keeping the leg stabilizing apparatuses from moving too far apart, and for varying the distance between the pedals. Some embodiments may have an elliptical wheel.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to pedal-powered single-wheeled vehicles, particularly those without seats. 
       BACKGROUND OF THE INVENTION 
       [0002]    Unicycles, most commonly pedal-powered and equipped with seats, are widely used for recreation as well as for acrobatic performance. As a recreation and exercise device, unicycles are difficult to learn to use. The difficulty provides an entertaining challenge but at the same time deters some people who otherwise would be interested in learning. 
         [0003]    There also exist seatless unicycles, popularly known as “Ultimate Wheel” or sometimes “Impossible Wheel” (although the latter may also refer to a seatless unicycle with unmoving foot supports). These require even more skill than seated unicycles because the user&#39;s feet on the pedals are the only points of contact between the user and vehicle. Without a seat it is extremely difficult to prevent the wheel from tipping sideways to an undesired degree during the pedaling motion. Unwanted sideways tilting of the vehicle can cause loss of side-to-side balance, or can hinder propulsion by causing an uncovered wheel to rub against the user&#39;s legs. 
         [0004]    A standing pedal-powered unicycle with means for greater lateral stability would therefore be useful as a more accessible alternative to the prior art, as a training device to prepare for more difficult types of unicycles, or simply to provide additional variety in the field. 
       SUMMARY OF THE INVENTION 
       [0005]    The present invention is a single-wheeled vehicle having greater lateral stability and precision of control than the prior art. The unicycle of the present invention has leg stabilizing apparatuses attached to the pedals and extending upward to come into contact with the user&#39;s legs when the user&#39;s feet are in place upon the pedals. The user can apply inward pressure to the leg stabilizing apparatuses to reduce unwanted side-to-side leaning during the pedaling motion, and to increase precision of control of the vehicle during turns, on slopes, and on rough surfaces. 
         [0006]    Some embodiments of the present invention may have an elliptical wheel. This overcomes the inherent difficulty of applying torque to the wheel at the points in the pedaling cycle when the two pedals are vertically aligned. 
         [0007]    The attainment of the foregoing and related advantages and features of the invention should be more readily apparent to those skilled in the art, after review of the following more detailed description of the invention taken together with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a perspective view of an embodiment of a vehicle in accordance with the present invention. 
           [0009]      FIG. 2  is a side view of the vehicle of  FIG. 1 . 
           [0010]      FIG. 3  is a side view of another embodiment of a vehicle in accordance with the present invention, having a sliding track for the pedals. 
           [0011]      FIG. 4  is a perspective view of another embodiment of a vehicle in accordance with the present invention, having an elliptical wheel. 
           [0012]      FIG. 5  is a side view of the vehicle of  FIG. 4 . 
       
    
    
     DETAILED DESCRIPTION 
       [0013]      FIGS. 1 and 2  show a vehicle  100  in accordance with the present invention. Vehicle  100  comprises a single wheel  110 , two pedals  120  coupled to wheel  110  for propelling the vehicle, and leg stabilizing apparatuses  130  coupled to pedals  120 . Wheel  110  has a single structural bar  111  spanning the diameter of the wheel, although in other embodiments the wheel can be constructed in a variety of different ways as known in the art. Pedals  120  are coupled to the sides of wheel  110  such that they can support a user who uses pedals  120  to drive wheel  110 . A leg stabilizing apparatus  130  is coupled to the inward sides of each of pedals  120 . Each leg stabilizing apparatus  130  comprises a vertical member  131  which extends generally upward from pedal  120 . (The directions “upward” and “vertical” apply to the position of leg stabilizing apparatus  130  when vehicle  100  is in use. These directions are “general” because leg stabilizing apparatus  130  pivots along with pedal  120  as the user&#39;s legs undergo small changes in angle during the pedaling motion.) A leg contact surface  132  is attached to each vertical member  131  at a height that allows it to contact the user&#39;s leg. 
         [0014]    In vehicle  100  of  FIGS. 1-2 , vertical member  131  is a single strut coupled to pedal  120  and to leg contact surface  132 ; in other embodiments, however, leg stabilizing apparatuses  130  may be constructed differently. For instance, vertical member  131  may be hinged such that it can fold downward toward pedal  120  (but is not foldable in the direction of the wheel, remaining rigid against inward force from the user&#39;s legs). Also, in other embodiments vertical member  131  and pedal  120  may be formed from the same piece of material. Likewise, vertical member  131  and leg contact surface  132  may be formed from the same piece of material. 
         [0015]    When the user is standing with his feet on pedals  120  and leg contact surfaces  132  in place against his legs, the user can apply inward pressure to leg contact surfaces  132 . This laterally stabilizes the vehicle and supports the user&#39;s legs, thereby enabling the user to control the vehicle much more easily than if the only points of contact between user and vehicle were the user&#39;s feet on the pedals. Using leg stabilizing apparatuses  132 , the user can more easily steer the vehicle, stay firmly connected to the vehicle on slopes and on rough terrain, and prevent the vehicle from unintentionally tipping sideways during riding as well as during mounting and dismounting. Leg contact surfaces  132  may be made of a yielding, slightly soft material, such as rubber. Leg contact surfaces  132  may also both have a concave curvature approximately conforming to the curvature of the medial surfaces of the user&#39;s legs. These features better enables leg contact surfaces  132  to be held against the user&#39;s legs through friction. Leg stabilizing apparatuses may be mounted with a slight outward slant in order to ensure that the user can easily apply pressure to leg contact surfaces  132 . 
         [0016]    Means may be provided for keeping leg stabilizing apparatuses  130  within a certain distance of each other, since their center of gravity relative to the pivot point of pedals  120  will otherwise cause them to freely fall forward or backward when they are not both held in place by the user. This may be achieved by a connecting element  140  coupled to both of leg stabilizing apparatuses  130 , preventing leg stabilizing apparatuses  130  from moving beyond a certain distance apart. Therefore when one of the leg stabilizing apparatuses is held in a generally vertical position by one of the user&#39;s legs, the other will remain in a similar position as well. Connecting element  140  may take various forms, such as an elastic band or a flexible strip of plastic (as shown in  FIGS. 1-2 ) coupled to the upper portions of both of vertical members  131 . 
         [0017]    An alternative means of keeping leg stabilizing apparatuses  130  within a certain distance of each other is by attaching a weight beneath each of pedals  120 , in order to bring the combined center of gravity of leg stabilizing apparatus  130  and pedal  120  to a point closer to the ground than the pivot point of pedal  120 . Leg stabilizing apparatuses  130  will therefore tend to stand generally vertical above pedals  120  even when not held in place by the user. 
         [0018]    Means may be provided for selectively coupling pedals  120  to wheel  110  at different distances from the center of wheel  110 , according to the user&#39;s preference. As shown in  FIGS. 1-2 , the wheel may have a plurality of pedal attachment points  121 , allowing the user to choose how far from the center of wheel  110  to attach pedals  120 . 
         [0019]      FIG. 3  shows an alternative to the plurality of pedal attachments points described above. In this embodiment structural bar  111  may have a track  122  along which pedals  120  can slide. Not only can sliding track  122  be used for fine control of the position at which pedals  120  are attached, it can also be configured to allow the distance between pedals  120  to be variable while they are being used to propel the vehicle. In the latter case, pedals  120  are biased (by springs or other means) so that they tend to keep a certain distance from the center of wheel  110 , but can move farther apart or closer together depending on the amount of force being applied by the user. The sliding track  122  can therefore be configured to automatically adjust the distance of the pedals  120  from the center of wheel  110  in order to facilitate propulsion during points in the pedaling cycle at which it is normally difficult apply torque. 
         [0020]      FIGS. 4-5  show another embodiment of a vehicle  200  in accordance with the present invention. Vehicle  200  differs from vehicle  100  of  FIGS. 1-2  in that the shape of the wheel is elliptical instead of circular. The elliptical wheel compensates for the difficulty of applying torque to the wheel during points in the pedaling cycle when the pedals are vertically aligned, thus fulfilling a similar function to the biased sliding track described above.