Traction attachment for tractors

Claim 1

FOR A TRACTOR HAVING A BODY, REAR WHEELS, FRONT WHEELS, A DRAW BAR EXTENDING REARWARDLY FROM SAID BODY, MEANS PIVOTALLY CONNECTING SAID DRAW BAR TO SAID BODY, A PAIR OF LIFT ARMS EXTENDING REARWARDLY OF AND PIVOTALLY CONNECTED TO SAID TRACTOR BODY, AND MEANS CONNECTED TO SAID ARMS FOR MOVING THEM IN AN ARCUATE PATH, THE IMPROVEMENT COMPRISING A RIGID, GENERALLY U-SHAPED MEMBER COMPRISING A PAIR OF UPRIGHT LEGS AND A STRAIGHT, HORIZONTAL CROSS MEMBER ATTACHED TO THE LOWER ENDS THEREOF, MEANS AT UPPER ENDS OF SAID LEGS TO PROVIDE A PIVOTAL ATTACHMENT OF SAID LEGS TO SAID LIFT ARMS WHEREBY SAID ARMS REMAIN IN GENERALLY UPRIGHT POSITIONS FOR ANY POSITION OF SAID LIFT ARMS, A YOKE COMPRISING A PAIR OF DEPENDING ARMS EXTENDING DOWNWARDLY ON EACH SIDE OF SAID DRAW BAR, A PAIR OF UPWARDLY EXTENDING ARMS ON EACH SIDE OF SAID CROSS MEMBER, MEANS HELD BY SAID DEPENDING ARMS FOR MOVABLY SUPPORTING SAID DRAW BAR WHEREBY SAID YOKE CAN MOVE IN A DIRECTION HAVING A COMPONENT DIRECTED LONGITUDINALLY OF SAID DRAW BAR, A ROLLER ROTATABLY HELD BY SAID UPWARDLY EXTENDING ARMS ABOVE SAID CROSS MEMBER FOR CONTACTING SAID CROSS MEMBER AND MOVABLY SUPPORTING SAID YOKE AND SAID DRAW WHEREBY SAID YOKE CAN MOVE IN A LINEAL PATH PARALLEL TO SAID CROSS MEMBER AND SAID DRAW BAR CAN MOVE IN AN ARCUATE PATH, THE CENTER OF WHICH CONSTITUTES THE POINT OF THE PIVOTAL CONNECTION OF SAID DRAW TO SAID BODY.