Arch wire locking device for orthodontic bracket

Claim 1

IN AN ORTHODONTIC BRACKET ADAPTED TO BE ATTACHED BY ONE END THEREOF TO A TOOTH BAND SUSBTANTIALLY PERPENDICULAR THERETO FOR SUPPORTING AN ARCH WIRE IN A REQUIRED ORIENTATION WITH THE TOOTH BAND, THE BRACKET INCLUDING A CYLINDRICAL BODY HAVING A LONGITUDINAL THREADED BORE THERETHROUGH WITH AN OPEN SLOT INTERSECTING SAID BORE SUBSTANTIALLY PERPENDICULAR THERETO, AND A LOCKING SCREW THREADEDLY ENGAGED IN SAID BORE HAVING A TAPERED END FACE FOR ENGAGING AND LOCKING SAID ARCH WIRE IN SAID SLOT, THE RADIAL DIMENSION OF THE SCREW BEING OF A LARGER DIMENSION THAN THE MAXIMUM CROSS-SECTIONAL DIMENSION OF ANY ARCH WIRE BEING ENGAGED; THE IMPROVEMENT WHICH COMPRISES: A SLOT HAVING AN ARCH WIRE ENGAGING SURFACE SUBSTANTIALLY PARALLEL TO THE AXIS OF SAID BORE, SUBSTANTIALLY TANGENTIAL WITH THE INNER PERIPHERAL SURFACE OF SAID BORE AND CONSTITUTING THE BOTTOM OF SAID SLOT WHEREBY AN ARCH WIRE MAY BE SUPPORTED IN SAID SLOT BY BEING CLAMPED THEREIN BETWEEN THE BOTTOM AND BAND SIDE OF SAID SLOT AND THE TAPERED END FACE OF SAID LOCKING SCREW, THE DEGREE OF TAPER OF SAID TAPERED END FACE BEING SUBSTANTIALLY 45 DEGREES WITH RESPECT TO THE LONGITUDINAL AXIS OF THE LOCKING SCREW.