Patent ID: 7073604

Claim:
In an agricultural machine having a main frame section, a pair of inner wing frame sections hingedly connected to opposite outer ends of the main frame section, and a pair of outer wing frame sections hingedly connected to outer ends of respective inner wing frame sections, the improvement comprising: a pair of outer lift cylinders operably coupled between respective inner and outer wing frame sections for raising and lowering the outer wing frame sections relative to the inner wing frame sections; a pair of inner lift cylinders operably coupled with respective inner wing frame sections for raising and lowering the inner wing frame sections relative to the main frame section; and a holding cylinder operably interconnecting said inner lift cylinders for selectively adjusting the position of the inner lift cylinders, said outer lift cylinders said inner lift cylinders and said holding cylinder being interconnected in a common hydraulic folding circuit whereby the outer wings are swingable between an unfolded position wherein the outer wings extend generally horizontally outwardly from the inner wings and a folded position wherein the outer wings are raised up out of the unfolded position and the inner wings are swingable between an unfolded position wherein the inner wings extend generally horizontally outwardly from the main frame and a folded position wherein the inner wings project upwardly from the main frame.