| 摘要 |
A hand powered cart uses a drive mechanism having a power lever operated by the operator's hands and arms, and is steerable by the operator's feet. The drive mechanism includes a closed drive chain that is given forward motion by a one-way freewheeling power sprocket, and that loops around idler sprockets, a drive sprocket, and a take-up sprocket. The power sprocket is attached to a reciprocating power lever, and moves back and forth. When moving forward, the power sprocket drives the drive chain. When moving backwards, the power sprocket freewheels without disengaging from the chain. The take-up sprocket is forced against the chain by a spring, and maintains the chain within a predetermined range of tension.
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