Blind fastening device with collapsible tube

Claim 1

A BLIND FASTENER ADAPTED TO FIT IN A HOLE IN AN OBJECT COMPRISING: A TUBE HAVING A CENTRAL AXIS, AN AXIAL HOLE EXTENDING FROM A FIRST END THEREOF, A FIRST CIRCULAR CYLINDRICAL SURFACE DEFINING AT LEAST A PORTION OF THE HOLE, A SECOND CIRCULAR CYLINDRICAL SURFACE DEFINING AT LEAST A PORTION OF THE OUTSIDE CONTOUR OF THE TUBE, SAID CYLINDRICAL SURFACES BEING COAXIAL AROUND THE CENTRAL AXIS, AT LEAST A PORTION OF THE SECOND CYLINDRICAL SURFACE BEING AXIALLY ALIGNED WITH AT LEAST A PORTION OF THE FIRST CYLINDRICAL SURFACE, THE ALIGNED PORTIONS BEING CONTINUOUS AND UNGROOVED, AND INTERNAL THREADS IN THE HOLE ON THE OPPOSITE SIDE OF THE FIRST CYLINDRICAL SURFACE FROM THE FIRST END, THE RATIO OF LENGTH OF THE AXIALLY ALIGNED PORTIONS OF THE CYLINDRICAL SURFACES, THE WALL THICKNESS OF THE TUBE AND THE RADII OF THE CYLINDRICAL SURFACES AT THE AXIALLY ALIGNED PORTIONS BEING SUCH THAT COMPRESSIVE LOADING OF SAID TUBE WHICH IS EXERTED BY ENGAGING SAID THREADS AND PULLING THE TUBE TOWARD THE FIRST END WHILE OPPOSING MOVEMENT OF THE FIRST END, CAUSES THE TUBE TO BULGE OUTWARDLY IN AT LEAST TWO AXIALLY SPACED LOCATIONS INCLUDED IN THE AXIALLY ALIGNED PORTIONS OF THE CYLINDRICAL SURFACES; AND A RETAINER MEMBER INCLUDING A PAIR OF FRUSTO-CONICAL PORTIONS SEPARATED BY A GROOVE, BOTH OF SAID FRUSTO-CONICAL PORTIONS BEARING AXIAL KNURLS, BOTH KNURLS LYING SLOPED RELATIVE TO THE ATXIS, THE GREATEST DIAMETER OF BOTH BEING LESS THAN THE OUTER DIAMETER OF THE TUBE FACING THE RETAINER MEMBER, THE KNURL LYING CLOSER TO THE TUBE WHEN THE KNURLS FACE THE TUBE HAVING SMALLER DIAMETERS THAN THE DIAMETERS OF THAT KNURL WHICH LIES FARTHER FROM THE TUBE, THE RETAINER MEMBER HAVING AN AXIAL HOLE EXTENDING THERETHROUGH, AND A TAPERED WALL SECTION PARTIALLY BONDING THE AXIAL HOLE IN THE RETAINER MEMBER FOR ENGAGEMENT BY AN ANVIL MEMBER WHEREBY THE ANVIL MEMBER WILL, WHEN PRESSED AGAINST IT, EXPAND THE LARGER END OF THE RETAINER MEMBER INTO THE WALL OF THE HOLE IN THE OBJECT, AND WHEREBY COMPRESSION OF THE TUBE AND RETAINER CAUSED BY PULLING ON A MANDREL ENGAGED TO THE THREADS IN THE TUBE IN OPPOSITION TO FORCE EXERTED ON THE RETAINER MEMBER BY AN ANVIL MEMBER FORCES THE FIRST END INTO THE GROOVE, AND THE KNURLS INTO THE WALL OF THE HOLE, AND UPSETS THE TUBE TO FORM A PLURALITY OF BULGES, THEREBY ATTACHING THE FASTENER TO THE OBJECT.