| 摘要 |
A portable telescopic mast assembly with positive retraction for raising and lowering an associated device includes an outer body and a plurality of mast sections slideably engaged with the outer body. A lifting cable is disposed between the plurality of mast sections. The lifting cable operatively connects the plurality of mast sections so as to urge one or more of the mast sections towards an extended position. The lifting cable includes a first end and a second end, the first end being secured to an inner most mast section of the plurality of mast sections. A retraction cable is disposed at least partially inside the outer body. The retraction cable includes a first end and a second end, the first end being secured to the inner most mast section. A winch is secured to the outer body. The winch includes a first output and a second output, the second end of the lifting cable operatively connected to the first output and the second end of the retraction cable operatively connected to the second output. |
