Patent ID: 8820338

Claim:
A walker adapted to navigate stairways and inclined surfaces comprising: a) two substantially parallel U-shaped leg modules, each leg module comprising; a substantially horizontal handle; and a front and rear leg, each front leg having a tubular upper section and a tubular lower section, the diameter of each said lower section being smaller than the diameter of the corresponding upper section and being partially slideably contained therein; b) a plurality of substantially horizontal struts fastening the leg modules together; c) two substantially vertical linear actuators each comprising an upper section and a lower section, each upper section having a rotatable, threaded drive rod and each corresponding lower section having a fixed threaded nut threaded on said drive rod, the upper section of each linear actuator being attached to the upper section of one front leg and the lower section of each linear actuator being attached to the lower section of the same front leg; d) an electric motor coupled to and capable of rotating the drive rods of said linear actuators; and e) a control for activating said electric motor; whereby activation of said electric motor causes rotation of said drive rods, which in turn causes extension or retraction of the front leg sections of the leg modules substantially in concert, wherein each of said linear actuators comprises a tubular upper cover section and a tubular lower cover section, the diameter of each said lower cover section being smaller than the diameter of the corresponding upper cover section and being partially slideably contained therein; the threaded drive rod is contained within the upper cover section and the threaded nut is attached to the lower cover section; the upper cover section of each linear actuator is attached to the upper section of one front leg and the corresponding lower cover section of said linear actuator is attached to the lower section of said front leg; whereby, as said nut travels along the threaded drive rod when the motor is engaged, such travel in turn causes the lower cover section to extend or retract thus extending or retracting the front legs.