04449590 is referenced by 24 patents and cites 7 patents.

An agricultural row marker assembly is provided which includes a three-piece articulated arm and which is hydraulically actuated. The assembly has a base which is connectable to an agricultural tool bar. A second arm is pivotally mounted to the first arm and a telescopingly extendable third arm is pivotally connected to the second arm. A marker disc is located at the distal end of the third arm. The arm is hydraulically actuated with the hydraulic cylinder acting on the first arm through a link member. A second link runs from the base to the second arm and a cable runs between the second link and the third arm so that extension of the hydraulic cylinders extendable rod urges all three arms in the substantially linear alignment.

Title
Row marker arm assembly
Application Number
6/420800
Publication Number
4449590
Application Date
September 21, 1982
Publication Date
May 22, 1984
Inventor
Gerald E Williamson
Macomb
IL, US
Agent
McWilliams Mann Zummer and Sweeney
Assignee
Yetter Manufacturing Co
IL, US
IPC
A01B 17/00
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