Rotary wheelchair lift apparatus

Claim 1

A rotary wheel chair lifting apparatus for lifting a user into and out of a vehicle of the type having a side door opening, such as a van, recreational vehicle, or the like, the lifting apparatus including: a support column adapted to be mounted adjacent said door opening; said support column constructed to have a polygonal cross-sectional configuration; a drive means for rotating said support column about a vertical axis, including a drive motor with drive gear means driving a gear means attached adjacent the lower end of said support column; a carriage assembly mounted for rolling engagement on said support column, the carriage assembly including a carriage member having at lease two oppositely disposed generally V-shaped rollers, each roller engaging two adjacent surfaces of said support column; the V-shaped rollers being of a configuration and location within said carriage member as to control; a frame structure including a support platform mounted on said carriage assembly for receiving a wheelchair; a drive screw means for raising and lowering said support platform platform in a vertical direction including an elongated screw member disposed in driven relationship with a screw drive motor attached to the upper end of said screw member, and a threaded engaging portion attached to said support column and said carriage assembly for raising and lowering said support platform upon actuation of said screw drive motor; said support platform having a forward stop means including a resiliently biased support member adapted for recriprocal movement upon engagement with wheels of said wheelchair; said support platform having a rear stop means including a hinged stop operably associated with a cable and pulley means for the automatic raising and lowering of said stop means upon raising and lowering of said frame structure, a control means on the frame for actuating the vertical and pivotal motion of said apparatus; the V-shaped roller include a means by which engagement between the rollers and said support column may be adjusted thereby establishing play between said support column and said carriage member, and an adjustment screw threadably connected to one axle of the V-shaped roller, the axle protruding through slots in opposing roller mounting block surfaces and having bearing surfaces engaging the slots, the adjustment screw protruding through an aperture in a further carriage member face threadable engaging a tightening means such as a nut whereby the adjusting means is caused to move.