| 摘要 |
<p>A drive assembly for a rider propelled vehicle (10) including a crankshaft (72) mounted on the vehicle for rotation about a drive axis and a pair of crank arms (74L, 74R) operatively connected to the crankshaft for rotating the crankshaft about the drive axis with the crank arms revolving around the drive axis. A pair of pedals (44L, 44R) are each capable of being driven by a pumping motion of one of the rider's legs along a repeating path through a first dead center position, and a second dead center position. A power arm (70L, 70R) and a link (76L, 76R) operatively connecting each of the pedals to a respective crank arm are operable to transmit the motion of the pedals to the crank arms and are movable relative to the crank arms so that when the pedals are in their respective first and second dead center positions the force applied by the rider's leg to the pedal in the second dead center position is directed by said connecting means along a line spaced from the axis of rotation of the crankshaft. In addition, a power assist device (84) is operatively connected to the vehicle and the crankshaft.</p> |
