Conveyor systems

Claim 1

A CONVEYOR SYSTEM OF THE KIND COMPRISING A PLURAL ITY OF ARTICLE SUPPORTING ELEMENTS POWER ADVANCED ALONG A TRACK ELEMENT, ONE OF SAID TWO ELEMENTS BEING PROVIDED WITH A PRE-SELECTABLE CONTROL DEVICE COMPRISING A PLURALITY OF CONTROL MEMBERS MOUNTED FOR INDEPENDENT ROTATIONAL MOVEMENT ABOUT A COMMON AXIS RELATIVE TO A SUPPORTING MEMBER CARIED BY SAID ONE ELEMENT SO AS TO BE MOVABLE BETWEEN AN INOPERATIVE POSITION AND AN OPERATIVE POSITION IN WHICH EACH CONTROL MEMBER CO-ACTS WITH OPERATING MEANS ON THE OTHER OF SAID TWO ELEMENTS CHARACTERIZED IN THE PROVISION OF MEANS ACTING BETWEEN EACH CONTROL MEMBER AND THEIR SUPPORTING MEMBER CONTROLLING THE ROTATIONAL MOVEMENT OF EACH CONTROL MEMBER RELATIVE TO ITS SUPPORTING MEMBER, SAID ROTATIONAL MOVEMENT CONTROL MEANS COMPRISING THE COMBINATION OF; (A) A PAIR OF AXIALLY OPPOSED THRUST PLATES, (B) A RESILIENT MEANS URGING SAID THRUST PLATES TOWARDS ONE ANOTHER, (C) ONE OF SAID TWO MEMBERS BETWEEN WHICH THE ROTATABLE CONTROL MEANS ACT HAVING A THROUGH OPENING THEREIN WITH A CONTROL BALL FREELY ROTATABLE WITHIN SAID OPENING AND ENGAGING ON OPPOSITE SIDES THEREOF WITH THE OPPOSED FACES OF SAID TWO MEMBERS (D) MEANS CONNECTING THE OTHER OF SAID TWO MEMBERS TO ONE OF SAID TWO THRUST PLATES, (E) SAID SO CONNECTED THRUST PLATE HAVING A PLURALITY OF BALL RECEIVING DEPRESSIONS SPACED CIRCUMFERENTIALLY AROUND SAID COMMON AXIS OF ROTATION, WITH SAID THRUST PLATE HAVING A V-SECTIONED PROJECTION PORTION SEPARATING CIRCUMFERENTIALLY ADJACENT DEPRESSIONS, (F) AND MEANS MOUNTING THE OTHER OF SAID TWO THRUST PLATES FOR FREE ROTATIONAL MOVEMENT ABOUT SAID COMMON AXIS.