| 摘要 |
A wheelchair is propelled by a left and right lever-operated, manual propulsion units and further comprise: low-level inclined cushioned seating 8,9; a longitudinally adjustable and pivoting footrest 11; unobstructed side boarding; a manually operated low-torque cable winch 48 that can be used in combination with a winch anchorage to lift the wheelchair into a vehicle [see 50, Figure 11]; progressive rear-wheel brakes 61 operated form the levers 20 of the manual propulsion units; the ability to steer the chair using differential braking; and lap and shoulder belts. Each manual propulsion unit preferably comprises a manually operated reciprocating lever 20, a drive unit 28 that converts motion of the lever into an oscillating rotary motion, and a conversion unit 31 that converts the oscillating rotary motion into continuous unidirectional motion and which provides output for driving a wheel of the wheelchair. Each propulsion unit makes use of chains and sprockets to transmit motion between at least the drive unit 28 and the conversion unit 31 and offers different modes of operation, e.g. forward, reverse, freewheeling, neutral. The conversion unit employs an epicyclic gear train [see Figs 12-17]. The wheelchair body is preferably formed from a pair of side panels 1 connected by cross-bracing struts 2. Braking may be achieved through movement of the levers 20 beyond their normal arcs of oscillation. |
