Patent ID: 6039273
Filing Date: 2000-03-21
Classification: A01G,Y10S

Abstract:
In combination:a corner pivot irrigation machine comprising a center pivot structure, a main arm extending outwardly from said center pivot structure supported upon and driven in either a forwardly or rearwardly direction by a plurality of non-steerable drive towers; an elongated corner arm pivotally secured to the outer end of said main arm and supported by a steerable drive tower;said steerable drive tower comprising:(a) an elongated main beam positioned beneath said corner arm and operatively connected thereto, said mean beam having opposite ends;(b) a drive wheel support positioned at each end of said main beam and being rotatable with respect thereto about vertical axes;(c) a drive wheel mounted on each of said drive wheel supports;(d) a steering motor secured to said main beam and having a rotatable drive shaft extending vertically therefrom;(e) an elongated first link arm, having opposite ends, having one end secured to said drive shaft and extending horizontally outwardly therefrom;(f) an elongated second link arm, having opposite ends, secured at one end to one of said drive wheel supports and extending outwardly therefrom;(g) an elongated third link arm, having opposite ends, secured at one end to the other of said drive wheel supports and extending outwardly therefrom;(h) and an elongated linkage pivotally secured to and extending between the other ends of said second and third link arms;(i) the other end of said first link arm being pivotally secured at said elongated linkage whereby rotation of said drive shaft of said steering motor causes said drive wheel supports to be pivotally moved;(j) the said one end of each of said second and third link arms being selectively adjustably secured, about a vertical axis, to the said drive wheel supports.