Patent Application
20180361196
Not Applicable
Not Applicable
Not Applicable
This invention relates generally to the field of human powered wheeled vehicles and more specifically to an elliptical drive system for a stepper type bike.
Numerous designers have developed and patented stepper bikes where the rider is in a standing position and presses his feet down on pedals to create forward motion. The primary objective is to have the user's feet travel in an elliptical fashion, similar to a stationary elliptical training machine found in many gyms or private homes.
Many of the previous designs have used chain drives combined with assorted linkages to produce this elliptical stepping effect. Additionally, most elliptical stepper bikes include some sort of sliding members to accomplish the desired effect. There is a deficiency in the prior technology in that chain drives can result in slipping gear teeth if not properly tensioned or cleaned, as well as losses in mechanical efficiency. Additionally, previous designs tend to have components that are relatively low to the ground which is problematic when riding on rough terrain. Previous designs also tend to include sliding members or rollers that can get jammed with sticks or pebbles. Finally, the previous designs do not provide significant options for adjusting linkages and stepping height to accommodate various leg lengths and overall body size.
The primary object of the invention is to provide an elliptical drive system for a two wheeled vehicle that has no drive train to clean or maintain.
Another object of the invention is to provide an elliptical drive system that needs no external rollers or sliders for the pedal mechanism.
Another object of the invention is to provide an elliptical drive system that eliminates the need for low hanging frame members, allowing for suitable ground clearance when operating on rough terrain.
A further object of the invention is to provide an adjustable linkage geometry that allows for optimal pedal path for different riders.
Yet another object of the invention is to provide a quadrilateral linkage that minimizes the vertical motion of the rider's feet, while guiding the feet in a natural motion, similar to that of walking.
Other objects and advantages of the present invention will become apparent from the following descriptions, taken in connection with the accompanying drawings, wherein, by way of illustration and example, an embodiment of the present invention is disclosed.
In accordance with a preferred embodiment of the invention, there is disclosed an elliptical drive system comprising: left and right rear crank arms, left and right pedal platforms, left and right main horizontal drive arms, left and right vertical drive arms, left and right short horizontal drive arms, left and right short lower drive arms, main horizontal frame member having an integral upwardly angled frame extension, U shaped horizontal frame member, front fork and steering member, a rear wheel hub, said front fork and steering member rotatably attached to said main horizontal frame member, said left and right short horizontal drive arms rotatably attached to said upwardly angled frame extension, said left and right vertical drive arms rotatably pinned to the ends of said short horizontal drive arms, said left and right short lower drive arms rotatably pinned at one end to said main horizontal frame where said horizontal member meets said upwardly angled frame extension and on the opposite end pinned to a mid-point on said vertical drive arms, said left and right main horizontal drive arms pinned at on end to said vertical drive arms and at the opposite end pinned to said left and right rear crank arms, said left and right rear crank arms fixedly connected at their opposite end to said central rear wheel hub, and said U shaped horizontal frame member fixedly attached at one end to the distal end of said main horizontal member and at the opposite end to said rear wheel hub.
The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention.
Detailed descriptions of the preferred embodiment are provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or manner.
The main horizontal drive member 6 remains a significant distance from the ground during all phases of the linkage cycle thereby making it ideal for use on rough terrain.
The elliptical motion for the step platform 46 during operation minimizes the vertical motion of the rider's feet, while guiding the feet in a natural motion, similar to that of walking.
While the invention has been described in connection with a preferred embodiment, it is not intended to limit the scope of the invention to the particular form set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.
