Access platform system with integrated folding steps

An access platform system for facilitating access to ground-based structures, vehicles, and mobile equipment, the system having:

• a main frame;
• a vertical displacement mechanism attached to the main frame, the vertical displacement mechanism having left and right sides and a platform assembly comprising
• a left intermediate carriage assembly,
• a right intermediate carriage assembly,
• a left lift cylinder having a stroke, and
• a right lift cylinder having a stroke;
• and
• a two-stage apparatus for influencing the stroke of the lift cylinders,
• one or more roller chains that guide the platform assembly, the chains engaging sprockets mounted on the left and right intermediate carriage assemblies which move together at a same speed and through a same vertical distance under the influence of the left and right lift cylinders,
• the chains and sprockets moving within the intermediate carriage assemblies, thereby influencing speed and travel range of motion of the vertical displacement mechanism so that travel speed and motion of the lift cylinders are equalized by controlling the pressure or flow of fluid provided to the cylinders, or by controlling the pressure and flow of fluid provided to the cylinders, so that the platform assembly advances upwardly at twice the speed as that of the left intermediate carriage assembly and the platform assembly lowers at twice the speed as that of the left lift cylinder, and so that the right and left lift cylinders and the right and left intermediate carriages work together to simultaneously raise and lower the platform assembly;
• the left intermediate carriage assembly and right intermediate carriage assembly each including guide bearings for vertical sliding engagement with vertical channel members associated with the main frame;
• the left and right sides of the vertical displacement mechanism also including guide bearings for vertical sliding engagement with vertical interior guide members within the left intermediate carriage assembly and right intermediate carriage assembly, thereby permitting free vertical movement, mechanical alignment and guidance during relative motion of the assemblies during operation;
• a folding steps assembly lacking a riser and having folding steps attached to the main frame, the folding steps assembly also having
• a folded up configuration that allows the vertical displacement mechanism to move upwardly and downwardly without interference by the steps, the folded up position blocking access to the ground-based structures, vehicle, and mobile equipment;
• and
• a folded down configuration in which the steps are secured in place, the folded down configuration representing a default configuration that requires no electrical power to permit ingress and egress of persons to or from the ground-based structures, vehicle, and mobile equipment in the event that electrical power is interrupted.