Abstract: The disclosure comprises a tray mountable under the floor of a vehicle, which tray contains an extendible ramp mechanism. This mechanism comprises a ramp and a driving panel for the ramp. The ramp is fulcrummed intermediate its ends on the outer ends of parallel arms extending from the driving panel. Also in the tray, as part of the driving mechanism, are a pair of parallel toothed belts driven by a reversible rotating motor, which belts are attached to the driving panel for extending and retracting the ramp from the tray. Mounted under the driving panel is a reciprocating motor connected by a crank arm to a shaft having additional crank arms pivotally connected to the underside of the ramp adjacent the driving panel. When the ramp is fully extended, the reciprocating motor tilts the ramp so that its inner end is moved upwardly to be flush with the floor of the vehicle. Simultaneously, the outer end of the ramp contacts the ground.

Abstract: Steps are convertible into a platform of an elevator for wheelchairs such as installed in vehicles and buses, during which conversion a barrier is automatically raised from the bottom step to be at the outer edge of the platform. The barrier is operated by an extensible link under the bottom step, which link is connected between the barrier and a crank arm keyed to an oscillatible transverse shaft under the inner part of the bottom step. Two additional crank arms are keyed to the ends of this shaft and are connected to a frame for a step or riser to oscillate said shaft when the steps are extended and unfolded into their platform position. The extendible link extends the barrier into a ramp when the platform is in its lowest position for access by a wheelchair. Reciprocating motors such as hydraulic pistons extend, retract, fold and unfold the panels that form the steps and their intermediate risers.