Movable steps for a transit vehicle

Movable steps for use on vehicles to facilitate movement of passengers to or from said vehicle comprising:

• a. a frame,
• b. a first step member operatively mounted to said frame having a horizontally disposed upper surface,
• c. a second step member operatively mounted to said frame having a horizontally disposed upper surface,
• d. means operatively associated with said step members for varying the vertical position of said step members between a first position wherein the step members are at different vertical heights to serve as entry stairs, to a second position wherein the step members are both level with the floor of the vehicle to form a platform, while maintaining the upper surfaces of said step members in a horizontal position, comprising a rotatably driven crank member operatively connected to a step member and wherein the rotatably driven crank is driven about its axis through an operating arc which extends from a first position wherein the step is in its down position to a second position wherein the step is in a raised position, said second position being on the opposite side from first position of a vertical plane through the axis so that a force such as the weight of a passenger standing on the step member forces said crank away from its operating arc,
• e. linkage means pivotally connecting said first and second step members to the frame comprising:
• 1. a first linkage arm having first and second ends;
• 2. pivotal mounting means connecting the first end of the first linkage arm to the second step member;
• 3. pivotal mounting means connecting the second end of the first linkage arm to the frame such that the pivot point of said pivotal mounting means is permitted to move toward and away from the step members as the step members change vertical positions;
• and
• 4. a second linkage arm pivotally connected to said first linkage arm intermediate its ends and pivotally connected to said first step member.