Patent ID: 8070134
Filing Date: 2011-12-06
Classification: B63C,B66C,B66D

Abstract:
1. A lift system for raising and lowering a load comprising: a substantially rigid platform; first, second, third and fourth fixed supports spaced apart and positioned around said platform; a power source connected to said first support; a first inextensible line fastened at one end to said third support and at another end thereof to said power source, said third support positioned diagonally opposite from said first support; said first line extending downwardly from said power source and beneath a pulley connected to a first dockside facing corner of said platform, then extending along a dockside edge of said platform and around a pulley connected to a second dockside facing corner of said platform, then extending upward and around a pulley connected to said second support, then downwardly and around another pulley connected to the second dockside facing corner of said platform, said first line then extending across one end of said platform to a pulley connected to a first outer corner of said platform and upward to said third support; a second line fastened at one end to said third support and, at another end thereof, to said power source; said second line extending downwardly from said power source to another pulley connected to said first dockside corner of said platform, then extending across another end of said platform to a pulley connected to a second outer corner of said platform, then extending upwardly and around a pulley connected to said fourth support, then downwardly and around another pulley connected to said second outer corner, then extending along an outer edge of said platform and around another pulley connected to said third outer corner and upwardly to said third support; said first and second lines and corresponding said pulleys each producing a mechanical advantage between said power source and said third support to lift said platform of four.