Patent ID: 8622159

Claim:
A tracked device ( 10 ), which includes: (a) a main carrier frame ( 12 ); (b) a battery containment area ( 14 ) carried on the main carrier frame ( 12 ); (c) a motor controlled movement system ( 16 ) for use with a seating system or for use with other implementable systems, which is attached to the main carrier frame; (d) a device ( 18 ) carried on the main carrier frame for use in transporting persons or equipment (such as a wheelchair seat system or other structural device); a. allowing the movement of said system to articulate as needed to offset weight distributions and counter balance the devices' movement during normal and off center axis operations (such as when going up/down stairs or across uneven ground); (e) a pair of side motion units ( 20 ) used to raise/lower a pair of endless ground engaging tracks ( 22 ); wherein each side has an actuator system ( 24 ) that will allow the the pair of tracks ( 22 ) to articulate into a “raised” or “lowered” position in order to position the tracked unit into the needed position for use; (f) the pair of endless ground engaging tracks ( 22 ) having one track located within an assembly adjacent each side of the main carrier frame, where in each track is entrained around a rotatable rear drive member and a pair of rotatable idlers carried on each side of the frame, wherein the idlers comprise a front idler and a trailing idler behind the front idler, the rear drive member of each track being operatively driven by the prime mover to propel the frame via the tracks; (g) a pair of idler supports ( 26 ) with one idler support located adjacent each side of the frame, wherein the idler supports are pivotally carried on the frame for rotation about an idler support pivot axis; (h) wherein the front ( 28 ) and trailing idlers ( 30 ) in each pair of idlers ( 26 ) are rotatably journaled on one of the idler supports for rotation about a front idler axis and a trailing idler axis, respectively, carried on the idler support, wherein the front idler axis an the trailing idler axis are fixed relative to the idler support with the idler support pivot axis being located between the front and trailing idler axis; being located between the front an trailing idler axes; (i) a pair of hangers ( 32 ) movably connected to the frame with one hanger being adjacent each side of the frame, wherein each idler support is carried on one of the hangers such that the idler support pivot axis moves with the hanger; (j) a fastener ( 34 ) connected to each hanger for fixing the hanger in a stationary operational position on the frame with the track being tensioned around the rear drive member and the idlers; and wherein the device ( 18 ) carried on the frame is configured to remain parallel to the plane of the contact area when the tracking device ( 10 ) climbs or descends stairs or other obstacles.