EXTENSION LADDER INCORPORATING A WINCH-OPERATED ELEVATOR

摘要

A conventional extension ladder modified to incorporate a foldable-platform-equipped trolley that can be raised and lowered with an electrically-powered winch. An open-channel guide rail is secured to each side of each section of the extension ladder, the guide rails extending the entire length of each section. Each side of the trolley is equipped with upper and lower sets of rotatable guide wheels. Each set comprises three guide wheels in stacked alignment. The trolley always runs on at least one pair of guide rails on opposite sides of the ladder, and may be running on both pairs of guide rails when it is positioned in the region of ladder section overlap. The trolley is equipped with upright posts to which a hand rail is secured. Extendable standards on the ladder base provide additional stability, and a pair of large wheels enhance ladder mobility.

主权项

1. An improved extension ladder incorporating a winch-operated elevator comprising:
an two-section extension ladder, each section having a pair of parallel rails interconnected by a plurality of rungs; an open-channel guide rail is secured to an outer side of each rail of each section of the extension ladder, each guide rail extending a major portion of an entire length of each section; a trolley having a framework, a foldable platform for support of an operator, and parallel side plates having inner surfaces facing the guide the guide rails; two sets of guide wheels rotatably secured to the inner surface of each side plate, each set comprising three guide wheels in stacked alignment, said trolley always travels on at least one pair of guide rails on opposite sides of the ladder, said trolley traveling on both pairs of guide rails when it is positioned in the region of ladder section overlap; a pulley secured to an uppermost rung of an upper section of said extension ladder; an electric-motor-powered winch secured to a bottom portion of a lowermost ladder section; a cable having a first end secured to said trolley, said cable being wrapped over said pulley and having a second end thereof secured to a rotatable drum of said winch, said winch lifts.