US Patent 9145908 Blind fastener

A blind fastener adapter for a conventional screw-threaded nut and screw comprises a collar and a segmented ring over the collar, the ring and collar having a tapered interface wherein relative axial movement results in a change of diameter of the ring. The adapter further includes a spring adapted to bias the collar and ring into mutual engagement; the collar and ring include means to prevent substantial relative angular movement thereof. The collar is adapted for engagement by a blind side head of the screw in use, and the ring is adapted for blind side engagement of the perimeter of a hole.