Articulated joint assembly

Claim 1

IN A COUPLING ADAPTED TO COUPLE TOGETHER TWO SECTIONS OF AN ARTICULATED VEHICLE WHICH INCLUDES FIRST AND SECOND VEHICLE SECTIONS ARRANGED IN TANDEM, THE IMPROVEMENT OF A SLEEVE JOINT HAVING A FRONT PORTION AND A REAR PORTION CONNECTED TOGETHER IN END-TO-END RELATIONSHIP BY A BALL AND SOCKET JOINT WITH THE LATTER DEFINING THE PIVOT CENTRE OF SAID SLEEVE JOINT, THE FREE END OF THE FRONT SLEEVE PORTION BEING ADAPTED FOR CONNECTION OF THE FIRST SECTION OF THE VEHICLE, AND THE FREE END OF THE REAR SLEEVE PORTION BEING ADAPTED FOR CONNECTION TO THE SECOND SECTION OF THE VEHICLE, AND A YOKE RING ROTATABLY CONNECTED TO SAID FRONT SLEEVE PORTION THEREBY PERMITTING ROTATION OF THE RING ABOUT THE AXIS OF THE FRONT SLEEVE PORTION, A PAIR OF HYDRAULIC ACTUATORS EACH CONNECTED AT ONE END TO SAID ROTATABLY MOUNTED YOKE RING AND ADAPTED TO BE CONNECTED AT THE OTHER END TO SAID SECOND SECTION OF THE VEHICLE, SAID HYDRAULIC ACTUATORS EXERTING A VEHICLE STEERING FORCE EXTENDING FROM THE SECOND VEHICLE SECTION THROUGH SAID ROTATABLE YOKE RING TO THE FRONT PORTION OF SAID SLEEVE JOINT, THEREBY TO CAUSE ANGULAR DISPLACEMENT OF THE FIRST AND SECOND VEHICLE SECTIONS RELATIVE TO EACH OTHER ABOUT THE PIVOT CENTRE OF THE SLEEVE JOINT AND THEREBY CAUSING THE ARTICULATED VEHICLE TO PROCEED IN A CIRCULAR PATH WITH THE RADIUS OF SAID PATH BEING DETERMINED BY THE EXTENT OF SAID RELATIVE ANGULAR DISPLACEMENT.