Abstract: An improved safety barrier/ramp actuation mechanism for combination folding stair and platform wheelchair lifts which translate from one configuration to the other depending upon the purpose to be served and have a combination safety barrier/ramp at the outboard end of the platform, the mechanism comprising a triple link mechanism and internally contained piston and bellcrank for reciprocating said barrier/ramp, and a pressure relief for said system to prevent raising said barrier/ramp when a load is resting thereon in ramp position, and the invention includes new steps in the method of operation of the stair and lift combination to enhance the safety thereof.

Abstract: A combination folding stair and platform wheelchair lift which translates from one configuration to the other depending upon the purpose to be served utilizing a series of panels which form a flat platform or alternatively steps and risers and which reciprocate horizontally on a pair of side rails and which are raised and lowered vertically in a pair of side column frames by a pair of hydraulically driven endless chains.