Abstract:
An improved structure for an exercise device having dual pedals wherein each pedal operates in a rotary manner in a vertical plane parallel to the bilateral axis of the user with each of the user&#39;s feet disposed, respectively, on a different one of the dual pedals.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is based on Provisional Application Ser. No. 61/854,751 filed May 1, 2013, which is hereby incorporated by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention resides in the field of exercise equipment and more particularly relates to bicycle style pedal or crank leg motivated devices. 
     2. Description of the Prior Art 
     This disclosure relates to a foot pedal operated exercise machine wherein two side-by-side pedal units are arranged to rotate in a vertical plane parallel to a vertical plane through the users bilateral axis. A suitable structure for, and the operation of, such a device are fully illustrated in U.S. Pat. No. 7,108,638 by the same inventor which is hereby incorporated by reference. 
     As disclosed in that patent, a pulley and belt arrangement combination provides counter-rotating movement of two crank arms. The pulleys are fixed to an axle or shaft at one end and a crank arm at the opposite end. A pedal is attached to the crank arm that the user stands on to create circular motion. The crank arm and pulley are both affixed to a shaft that rotates on bearings in a tube secured to a frame. There is one of these assemblies positioned on the left and one on the right of the frame, one for each foot. The crank arm is on the front side of the tube and frame and the pulley is on the backside. This mechanical system creates counter rotation of the two crank arms by the arrangement and operation of the component parts as further described in that patent. 
     An improved and alternative structure which functions to provide a pedal motivated exercise device for side-by-side rotation, as opposed to the better known back to front bicycle style machines, is presented below. 
     SUMMARY OF THE INVENTION 
     The invention described herein utilizes a fixed instead of a moving axel or shaft. In this arrangement, a sprocket gear and crank arm rotate on an axel instead of being fixed to a shaft and rotating the entire combination inside of a bearing or tube. In this new improved design, the crank arm and sprocket gear are directly attached to one another rather than being separated by a moving shaft. Counter rotation between one side and the other is created by, for example, the use of two idler gears connected by roller chains, or by the direct meshing of the right and left sprocket gears. 
     The advantages and features of the invention will be further understood from the description of the preferred embodiment and drawings which follow. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view illustrating a preferred embodiment of the invention in exploded format; 
         FIG. 2  is an assembled perspective view of the preferred embodiment of  FIG. 1 ; 
         FIG. 3  is a top view of the preferred embodiment of  FIG. 2 ; 
         FIG. 4  is a front view of the preferred embodiment of  FIG. 2 ; 
         FIG. 5  is a side view of the preferred embodiment of  FIG. 2 ; 
         FIG. 6  is a rear view of the preferred embodiment of  FIG. 2 ; 
         FIG. 7  is a perspective view illustrating an additional preferred embodiment of the invention in exploded format; and 
         FIG. 8  is an assembled perspective view of the preferred embodiment of  FIG. 7 . 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIG. 1 , there is shown in perspective assembly format a first example of the parts of the invention in which frame  1  provides the support base for the rotating and synchronizing components of the machine. Right and left pedal crank assemblies  2  and  3  are each rotatably mounted on axels  20  extending from frame crossbar  22  and supported by diagonal uprights  24  and  26 . Each assembly consists of a rotatable pedal support member  28  having, at the opposite end of the axel mount, a pedal mount  4  having axel  30  which is rotatably mounted in hub  32 . Pedal mount  4  is attached to a timing belt sprocket  34  which rotates on pedal mount axel  30 . At the opposite end of support member  28 , a second timing belt sprocket  7  is attached to axel  20 . Timing belt sprockets  7  and  34  are linked by timing belt  9 .  FIG. 7  illustrates a suitable pedal  38  attachable to pedal mount  4 . 
     As both the right and left pedal crank assemblies  2  and  3  rotate about axels  20 , timing belts  9  will also rotate resulting in the rotation of timing belt sprockets  34  (one turn per the revolution of each crank) which will in turn result in the upper surface  36  of the pedal  38  always remaining in a horizontal plane. 
     The pedal assemblies are linked together so as to provide coordinated motion of the users legs when operating the machine. Two examples of such linkage arrangements are illustrated herein. The first is shown in  FIG. 1  and the additional views of the same structure in  FIGS. 2-6  illustrating perspective, front, back, top, and side views of the entire machine; and the second as depicted in  FIGS. 7 and 8 . 
     Referring again to  FIG. 1 , left pedal crank assembly  3  is coaxially connected to sprocket gear  40  and upon rotation simultaneously turns gear  40  which is engaged with roller chain  42  which in turn engages sprocket  44  similarly connected to the right pedal crank assembly  2 . Each combination sprocket gear and crank assembly, i.e., crank  3  and gear  40  and crank  4  and gear  44  thereby function and rotate together as synchronized units. 
     Chain tensioner  5  provides an automatic adjustment for variations in the slack in chain  42 . This combination establishes the synchronization of the left and right pedal cranks Additionally, sprocket  46  is coaxially mounted with and fixed to sprocket gear  44  and functions to drive roller chain  18 , which in turn rotates sprocket  16  mounted on frame  1  by shaft  13 . Sprocket  48  is coaxially mounted with and fixed to sprocket gear  17  which engages and drives roller chain  50 . 
     Chain  50  engages sprocket  52  and in turn drives generator/flywheel  6  providing power for electrical displays and calculations of operational parameters as well as enhancing the smooth running of the machine. 
       FIGS. 7 and 8  show a second structure for providing the linkage and auxiliary functions described above. In this approach, the pedal crank assemblies  56  and  58  are mounted directly on synchronizing gears  60  and  62 , which mesh thereby turning together to provide the linking function. These gears and their associated pedal crank assemblies are mounted on and directly rotate about axles  64 . The timing belt arrangement for pedal orientation operates in the same manner as that previously shown. 
     Idler gear  66  is fixed to idler shaft  68  and engages with and is rotated by meshed gears  60  and  62 . The consequent rotation of shaft  9  may be arranged to operate a generator and or flywheel, shown schematically, or any other appropriate device similar to the configuration illustrated in  FIG. 1 . 
     The invention is accordingly defined by the following claims.