| 摘要 |
<p>The bicycle crank wheel for use with a derailleur gear, has two rings of teeth (5,6) the larger dia. ring (5) being in a different plane from that of the smaller dia. ring (6). These rings are attached to radial arms (1) projecting from a boss (5) through which passes the spindle to which the pedal cranks (4) are attached. The two rings are attached to the same side of the arms, with their inside edges mounted on shoulder (10) projecting on the opposite side to that of the projecting boss. Each ring has holes through it, to fit over pegs (8,9) which project from the arms, and which are then riveted over to lock the rings against the shoulders.</p> |
