| 摘要 |
A lifting device for lifting elongate objects such as watercraft from trailers or the like to overhead storage positions has a plurality of individual lines passing over a plurality of pulleys generally configured in a rectangular shape and supported from an overhead support such as a ceiling. First ends of each of the individual lines are attached to slings underlying the watercraft. Second ends of the individual lines pass through gathering means along a longitudinal axis. A multiple purchase block and tackle system also runs along the longitudinal axis, and has first and second ends attached by a hauling line. The individual lines each have second ends attached to the first end of the block and tackle system, so that as the block and tackle first end is moved each of the individual lines is moved simultaneously and an equal distance. Uniform, mechanically advantageous lifting of the watercraft is thereby achieved by manipulation of a single hauling line. |
