| 摘要 |
<p>This invention is a bicycle crank and pedal assembly with a self-extending a nd retracting crank arm. The assembly only has three one-piece components that move relative to each other, if the bearings used in friction reduction are ignored. It is simple, compact and very effective in delivering the benefits of a self-extending and retracting crank arm. In particular, the assembly has (i) the maximum arm length for over 90 degrees of arm positions in the power down stroke and (ii) the minimum arm length for close to 90 degrees of arm positions in the return up stroke.</p> |
