Patent ID: 7434489
Filing Date: 2008-10-14
Classification: B62M,F16H,Y10T

Abstract:
1. A bicycle drive system comprising: a. a first face gear wheel including at least two first concentric face gears and a plurality of dowel pins extending from a surface of the first face gear wheel; b. a second face gear wheel including at least two second concentric face gears and a plurality of dowel pins extending from a surface of the second face gear wheel; c. a variable length drive shaft having an axis of rotation and having a first end and a second end; and d. a first gear shift assembly coupled to the first end of the drive shaft and engaging one of the first concentric face gears; and e. a second gear shift assembly coupled to the second end of the drive shaft and engaging one of the second concentric face gears, wherein upon initiating of a gear shift both the first gear shift assembly and the second gear shift assembly are simultaneously actuated such that the first gear shift assembly maintains a current position relative to the engaged first concentric face gear and the second gear shift assembly moves to and engages an adjacent second concentric face gear as the second face gear wheel rotates to one of a plurality of alignment positions on the second face gear where gear teeth on an adjacent second concentric face gears are aligned in a radial direction, wherein the first face gear includes a plurality of alignment positions such that upon a subsequent gear shift both the first gear shift assembly and the second gear shift assembly are simultaneously actuated such that the second gear shift assembly maintains a current position relative to the engaged second concentric face gear and the first gear shift assembly moves to an adjacent first concentric face gear as the first face gear wheel rotates to one of the plurality of alignment positions on the first face gear where gear teeth on adjacent first concentric face gears are aligned in a radial direction.