Access system and device for vehicles, and modes of employment thereof

An access system for a vehicle, including an access device having at least two tread units including a first tread unit and a second tread unit each having at least two fixed treads for supporting a user when in use, wherein the at least two fixed treads are fixed relative to one another, and each said tread unit articulatory connected to the next adjacent said tread unit by articulation connections such that the tread units close together during upward longitudinal retraction of the access device from a downwardly extended deployed orientation with the first tread unit above the second tread unit when the access device is deployed, characterised in that adjacent said tread units each includes a first fixed tread and a second fixed tread, and when retracted into a nested configuration the first fixed tread of a first said tread unit at least partially overlays the first fixed tread of the second said tread unit, and the second fixed tread of said first tread unit at least partially overlays the second fixed tread of the second tread unit, with the first fixed tread of the second tread unit positioned at least partially between the first and the second fixed treads of the first tread unit.

A method of retracting a deployed access device for earth moving equipment, the access device including a multiplicity of tread units, each tread unit including two or more fixed treads that are fixed relative to one another for supporting a user, the method including bringing the tread units closer together during a longitudinal contraction of the deployed access device, whereby the tread units nest together when the access device is fully retracted such that a first tread of a first tread unit overlays a first tread of a second tread unit and a second tread of the first tread unit overlays a second tread of the second tread unit, the first tread of the second tread unit being at least partially between the first and second treads of the first tread unit when the access device is retracted.

An access system for a vehicle, including a sectional access device having sections, at least two of the sections each including at least one tread unit having multiple fixed treads that are fixed relative to one another for supporting a user when in use, and each of the at least two sections articulatory connected together by articulation connections whereby the at least two tread units close together during upward longitudinal retraction of the access device from a downwardly extended deployed orientation, with each of the at least two said tread units having at least one tread that is stowed at least partially between treads of the multiple fixed treads of an other of the at least two tread units when the access device is retracted.

A retractable access device for a vehicle, the access device having a longitudinal extent when deployed, including a multiplicity of rigid tread units, each tread unit having multiple fixed treads, that are fixed relative to one another, the tread units interconnected by connectors pivotably mounted with respect to the tread units providing articulation between adjacent said tread units, the tread units nested together after retraction of the access device with at least one tread of each tread unit stowed intermediate the treads of at least one other of the tread units when the access device is retracted.

A retractable access device for a vehicle, the access device having a longitudinal extent when deployed, including a multiplicity of tread units, each tread unit having at least an upper tread and a lower tread, that are fixed relative to one another, the tread units interconnected by connectors pivotably mounted with respect to the tread units providing articulation between adjacent said tread units, the tread units nested together after retraction of the access device with the upper treads adjacent one another and the lower treads lying adjacent one another when the access device is retracted.