Three-point hitch assembly

A method for controlling implement position in relationship to a land vehicle, comprising:

• providing a hitch assembly for mounting an implement onto the land vehicle comprising,
• a pivotal mounting means for providing horizontal arcuate movement of said hitch assembly;
• an implement engagement means;
• providing a means for vertical arcuate movement of said implement engagement means between a raised position and a ground engagement position, said vertical arcuate movement means connecting said implement engagement means and said pivotal mounting means;
• providing a means for adjusting an angle of attack of said implement engagement means in relation to a vertical axis of a rear tower member which supports the implement;
• providing a means for tolerating and controlling horizontal movement of said implement engagement means;
• providing a means for positioning said implement engagement means at some point in relation to the pivotal mounting means when said hitch assembly is at its maximum height;
• engaging the implement with a three-point hitch by adjusting one point of the hitch and fastening to the implement;
• lowering said hitch assembly so that said implement engages the ground;
• driving said land vehicle across the ground and controlling said implement to limit horizontal arcuate movement about a longitudinal axis of travel which is parallel to direction of travel;
• raising said hitch assembly to disengage said implement from the ground and centering to a preselected position at about 75% of a highest hitch assembly setting, and
• locking the implement in a raised position for travel.

A hitch assembly attached to a land vehicle equipped with endless treads, for use in mounting implements behind said land vehicle, said assembly being movable between a raised position and a lowered operating position, said hitch assembly comprising:

• swivel mounting means for mounting said hitch assembly to said land vehicle and for providing arcuate horizontal swivel about a vertical axis;
• positioning means for moving said hitch assembly from said raised position to said lowered operating position, said positioning means comprising a four bar linkage formed by connecting arms, and a drive means, said arms connected pivotally to each other at corners of a four-sided polygon formed by at least two horizontal arms and at least two vertical arms, whereby one horizontal side of the polygon has means to adjust its length and be locked at a desired length, and two of said corners are held at fixed positions on said swivel mounting means, and two of said corners are held at fixed positions on implement engagement means;
• stop means to limit horizontal arcuate swivel of said four bar linkage about a vertical axis mounted on an inboard surface of said swivel mounting means;
• implement engagement means attached to a rearward portion of said at least two vertical arms;
• a telescoping rod positioning assembly pivotally mounted between said swivel mounting means and said implement engagement means to return said hitch assembly to one central point when said hitch assembly is fully raised;
• wherein said telescoping rod positioning assembly urges said implement engagement means to one point only until said implement engaging means has vertically and arcuately traveled up through about 75% of its vertical range of motion.

A three-point hitch assembly for enhancing steering correction on a tractor driven by a pair of endless tracks located on sides of the tractor, the improvement comprising:

• a vertically oriented swivel shaft having a vertical longitudinal axis mounted at a rear of the tractor and having means to allow rotational movement of said shaft about its vertical longitudinal axis,
• a four bar linkage coupled to said shaft and free to move about said shaft's vertical longitudinal axis,
• an implement engaging means coupled to said four bar linkage and free to move about said shaft's vertical longitudinal axis through said four bar linkage,
• means to move said four bar linkage such that said implement engaging means moves from a ground engaging deployed position to an elevated, retracted position,
• means to limit movement of said four bar linkage in an arc about said shaft's vertical longitudinal axis,
• means for returning said four bar linkage to a central position, aligned with a longitudinal axis of the tractor when said implement engaging means is in an elevated, retracted position,
• said four bar linkage is configured as a four sided polygon having a first arm substantially parallel to said shaft and pivotably connected thereto for movement thereabout, a second arm substantially parallel to said first arm and spaced therefrom and supported thereto by a pair of vertically spaced, parallel, horizontally oriented third and fourth arms which are connected to said first and second arms, thereby defining said four bar linkage,
• a ram extends between said fourth arm and said first arm to provide said moving means for said four bar linkage,
• said implement engaging means is coupled to said second arm, and
• wherein said fourth arm has clearance on a lowermost side thereof to accommodate a draw hitch bar thereunder, said draw hitch bar coupled to said tractor.