Positioning apparatus for drawn implement

In an agricultural implement of the type which has an elongated generally transverse tool bar and a hitch arm having a forward end for attachment to a mounting hitch of a drawing vehicle and means located on the implement for engaging the ground for guiding the implement, apparatus for varying the horizontal angular orientation of the hitch arm relative to the tool bar for the purpose of laterally positioning the implement to follow a desired path as the drawing vehicle draws the implement, said apparatus comprising:

• pivoting means including power means operatively attached to said hitch arm and said tool bar for generally horizontally pivoting the tool bar relative to the hitch arm to thereby adjust the angular orientation of the hitch arm relative to the tool bar, said power means being located in the same vertical plane as the tool bar and being substantially parallel to the tool bar;
• hitch sensing means for sensing the angular orientation of the hitch arm relative to the tool bar and generating a signal indicative of said sensed orientation;
• wand means operatively associated with said apparatus and configured to detect the lateral position of the implement relative to the desired path as the drawing vehicle moves generally along the desired path;
• wand sensing means for sensing the position of said wand means and generating a signal that is indicative of said sensed position;
• means for controlling said power means for adjusting the angular orientation of the tool bar relative to the hitch arm so that the implement follows the desired path of movement in response to said signals from said hitch sensing means and wand sensing means.

In an agricultural implement of the type which has an elongated generally transverse hollow tool bar with a generally rectilinear cross section and a hitch arm having a forward end for attachment to a mounting hitch of a drawing vehicle and means located near the rearward end of the implement for engaging the ground for providing a fulcrum for guiding the implement, the tool bar having an opening in the front face thereof through which a rearward end portion of the hitch arm and pivoting means of the apparatus can pass, apparatus for varying the horizontal angular orientation of the hitch arm relative to the tool bar for the purpose of laterally positioning the implement to follow a desired path as the drawing vehicle draws the implement, said apparatus comprising;

• pivoting means including a double acting hydraulic cylinder having a cylinder end and a retractable and extendable piston rod located within the confines of the tool bar, one of said cylinder end and piston rod being attached to said rearward end portion of said hitch arm and the other being attached to said tool bar for generally horizontally pivoting the tool bar relative to the hitch arm to thereby adjust the angular orientation of the hitch arm relative to the tool bar responsive to selective retraction and extension of said piston rod relative to said cylinder;
• hitch sensing means for sensing the angular orientation of the hitch arm relative to the tool bar and generating a signal indicative of said sensed orientation;
• wand means operatively associated with said apparatus and configured to detect the lateral position of the implement relative to the desired path as the drawing vehicle moves generally along the desired path;
• wand sensing means for sensing the position of said wand means and generating a signal that is indicative of said sensed position;
• means for controlling said pivot means for adjusting the angular orientation of the tool bar relative to the hitch arm so that the implement follows the desired path of movement in response to said signals from said hitch sensing means and wand sensing means.