Row marker arm assembly

Claim 1

An agricultural row marker assembly comprising: a base member connectable to a tool bar; a first arm pivotally connected to said base member; a second arm having a first end, a second end and a tail piece fixed to the first end, said first end pivotally connected to said first arm; a third arm pivotally connected to the second end of said second arm and having a row marker device mounted on said third arm; a hydraulic cylinder mounted to said base and including an extendable rod; a first link having one end pivotally mounted to said extendable rod and another end pivotally mounted to said first arm; a second link having one end pivotally mounted to said base and another end having a pin pivotally and slidably mounted in an elongated slot defined in said tail piece, said slot aligned to permit vertical deflection of said row marker when the assembly is fully extended but not permitting lost motion when the assembly is being retracted; and a cable having one end fixed to said second link at a point intermediate the two ends of said second link and another end fixed to said third arm whereby extension of said extendable rod urges said first arm into an extended position and applies tension to said cable urging said first, second and third arms into substantially linear alignment.