Theft prevention device for trailers

Claim 1

AN ANTI-THEFT LOCK COLLAR FOR A GENERALLY CYLINDRICAL, VERTICALLY DISPOSED TRAILER KINGPIN OF THE TYPE HAVING A REDUCED DIAMETER SECTION INTERMEDIATE ITS ENDS, COMPRISING, A PAIR OF SUBSTANTIALLY SEMI-ANNULAR MEMBERS; MEANS PIVOTALLY CONNECTING ONE END OF EACH MEMBER TO THE OTHER MEMBER WHEREBY SAID MEMBERS ARE MOVABLE BETWEEN A FULLY OPENED CONDITION WHEREIN THE SURFACES DEFINING THE FREE ENDS OF SAID MEMBERS ARE SEPARATED A DISTANCE GREATER THAN THE DIAMETER OF THE KINGPIN AND A CLOSED CONDITION WHEREIN SAID FREE END SURFACES ABUT EACH OTHER, SAID FREE END SURFACES BEING RELATIVELY FLAT AND LYING IN A PLANE CONTAINING THE PIVOTAL AXIS OF SAID MEMBERS WHEN IN THEIR CLOSED CONDITION, SAID MEMBERS BEING POSITIONABLE ON A KINGPIN AND MOVABLE TO SAID CLOSED CONDITION TO ENCIRCLE AND ENGAGE THE KINGPIN AND COVER AND OPERATIVELY ENGAGE THE REDUCED DIAMETER SECTION, THE PIVOTAL AXIS OF SAID MEMBERS BEING GENERALLY VERTICALLY DISPOSED WHEN SAID MEMBERS ARE POSITIONED ON THE KINGPIN IN SAID CLOSED CONDITION, THE FREE END SURFACES OF ONE OF SAID MEMBERS HAVING AN ELONGATED GROOVE FORMED THEREIN AND THE FREE END SURFACE OF THE OTHER OF SAID MEMBERS HAVING AN INTEGRALLY FORMED RIB PROJECTING THEREFROM, SAID RIB BEING RECEIVABLE IN SAID GROOVE WHEN SAID MEMBERS ARE IN THEIR CLOSED CONDITION, THE LONGITUDINAL AXES OF SAID RIB AND GROOVE BEING SUBSTANTIALLY PARALLEL TO THE PIVOTAL AXIS OF SAID MEMBERS; AND RELEASABLE LOCK MEANS FOR SECURING SAID MEMBERS IN THEIR CLOSED CONDITION.