A track drive system for a mobile irrigation system adapts to either
centrally pivoted circular or linear mobile systems, as desired. A first
embodiment has a single drive wheel with opposed first and second end
guide wheels, surrounded by a single narrow track. A single drive motor
and gear reduction drive, drives the central wheel. The central wheel is
of considerably larger diameter than the two end guide wheels, and
simultaneously contacts the track with both its upper and lower
peripheries at all times. The mechanism is articulated to allow
independent wheel movement relative to one another, thus providing better
traction over uneven surfaces. The central drive wheel is always in
contact with both the upper and lower track portion to provide continuous
drive traction for the device. A second embodiment includes additional
idler wheels between the two end wheels and the central drive wheel.
