Parallel linkage adjusting means for a tool bar

Claim 1

IN COMBINATION WITH A VEHICLE A RIGID SUPPORTING FRAME CARRIED BY GROUND ENGAGING MEANS: A PLURALITY OF VERTICAL LINKAGE ASSEMBLIES SPACED FROM ONE ANOTHER PERPENDICULARLY TO THE INTENDED DIRECTION OF TRAVEL OF SAID FRAME RELATIVE TO THE GROUND, EACH OF SAID ASSEMBLIES INCLUDING A FIRST ELEMENT FIXED RELATIVE TO SAID FRAME, A SECOND ELEMENT SPACED THEREFROM, AND A PLURALITY OF CONNECTING LINKS PIVOTALLY JOINING SAID FIRST AND SECOND ELEMENTS ABOUT SPACED HORIZONTAL AXES; A RIGID MEMBER SECURED TO THE SECOND ELEMENT OF EACH LINKAGE ASSEMBLY; CROSS SHAFT MEANS PIVOTALLY MOUNTED ON SAID RIGID MEMBER ABOUT A HORIZONTAL AXIS PERPENDICULAR TO THE INTENDED DIRECTION OF TRAVEL OF SAID FRAME RELATIVE TO THE GROUND, SAID CROSS SHAFT MEANS INCLUDING AN ARM RIGIDLY ATTACHED THERETO AND EXTENDING RADIALLY FROM SAID LAST-NAMED AXIS, SAID ARM BEING PIVOTALLY CONNECTED TO SAID FRAME AT A LOCATION REMOTE FROM SAID LAST-NAMED AXIS; AND MEANS OPERATIVELY CONNECTED BETWEEN SAID RIGID MEMBER AND SAID CROSS SHAFT MEANS ADAPTED TO SELECTIVELY PIVOT SAID CROSS SHAFT MEANS ABOUT SAID LAST-NAMED AXIS RELATIVE TO SAID RIGID MEMBER.