Patent ID: 7575098

Claim:
A lift system for lifting or lowering items from one level to another within a building, the system comprising: a lift platform; an upper level support structure having an opening configured to allow passage of the platform through the opening, the opening being suspended above a generally open area of a lower level; an upper level frame coupled to the upper level support structure; a winch having a motor that rotates a single drum supported by the upper level frame at a position spaced a substantial distance above the opening; four biasing members, each biasing member having having a length of about 10 to 16 inches and a spring constant of from 50 to 500 lbs/inch and that expands linearly 5 inches or more to provide an amount of play and tension on the lift platform when the lift platform is seated within the opening; four lengths of cable, each length of cable secured at one end to the winch and at an other end to separate areas of the platform through one of the biasing members; and wherein operation of the winch rotates the drum to wind or unwind the cable lengths to raise or lower the platform through the open area of the lower level without any laterally adjacent support or guidance structure within the open area.