3666019 is referenced by 18 patents and cites 15 patents.

A row marking apparatus including first and second row markers individually pivoted at one end on a tool bar of a tractor. Each marker is pivoted between raised and lowered positions by a ram having its cylinder connected to the tool bar and its piston rod pivotally connected intermediate the ends of the associated row marker. The flow of fluid to and from the ram is automatically controlled by a flow control valve which provides first and second isolated flow paths between a main valve and the rams. The flow paths cooperate with the rams to alternatively (1) sequentially raise and lower respective markers or (2) raise and lower an individual lowered marker.Each row marker is preferably formed in two sections which are pivotally interconnected at adjacent ends and which are moved between folded and end-to-end relation when the row marker is moved between the lowered and raised positions. This movement is accomplished by a cable having one end connected to the tool bar and an opposite end connected to the second section and an intermediate portion of the cable cooperating with a guide located adjacent the pivotal connection for the sections.

Row marking apparatus
Application Number
Publication Number
Application Date
October 7, 1969
Publication Date
May 30, 1972
Yeske Laurel R
J I Case Company
A01b 17/00
A01B 69/02
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