| 摘要 |
A portable load transporting dolly having a mechanism manually operable for selectively ascending or descending steps is shown. The dolly has generally cross-shaped wheels and a pivotal driving lever is located at its handle. A cable couples the pivotal driving lever to the rotating shaft of the cross-shaped wheels through a plurality of pulleys and ratchet gears such that the wheels may be rotated easily by gripping the lever. The radial arms of t he cross-shaped wheels have sliding reciprocative rods which react with the steps of the staircase to enhance the climbing action of the dolly on the staircase.
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