Abstract: A self-plugging blind fastener of the type having a tubular, headed, body, and a stem which is pulled and locked relative to the body to set the fastener, has improved locking means provided in the form of a deformable annular locking collar which is disposed on the stem, a locking groove on the plug part of the stem, and an annular recess at the head end of the body provided as an enlargement of the bore. The recess has a generally cylindrical outer region of substantially greater diameter than the main region of the bore, and a tapered inner region in which the diameter of the recess reduces to that of the main region of the bore. The recess can be stepped between the outer and inner regions.

Abstract: A self-plugging blind fastener of the break-stem type, is suitable for fastening apertured sheets together, and comprises a headed tubular body and an elongate stem disposed in the bore of the body. The stem comprises a plug, and a stem-tail connected to the plug by a breakneck which is concealed by overlapping lips. The plug has a stop face, and an annular locking groove between the breakneck and the stop face. The body has a deformable locking collar upstanding above an adjacent region of the upper surface of the head. The diameter of the bore reduces, to provide a stop face and a locking region of smaller diameter, within the head. The fastener is set by pulling the plug into the bore until the stop faces meet, to form a blind head, and then deforming the collar to force the body to bulge into the locking groove of the plug.

Abstract: In a blind fastener (20) of the kind comprising a tubular nut (22) having shank (28) with a head (30) at one end and a tapered nose (32) at the other end, a headed bolt (24) threadedly engaged in the bore (34) of the nut (22), and an expansible sleeve (26) which, by rotating the bolt (24), can be forced on to the nose (32) to form a blind head, a section of the shank (28) of the nut (22) is formed with a single protuberance (42) which protrudes resiliently into the bore (34) sufficiently to interfere with and restrain rotation of the bolt in the nut, and thus render the fastener self-locking. The shank (28) may have more than one section provided with a single such protuberance (42), the effect of several protuberances being additive. Each protuberance (42) lies entirely within a minor sector of its section of the shank, and presents either a flat or a curved threaded surface traversed by the thread (38). Protuberances may be in different sectors if spaced longitudinally of the shank.

Abstract: A self-plugging blind fastener of the break-stem type, is suitable for fastening apertured sheets together, and comprises a headed tubular body and an elongate stem disposed in the bore of the body. The stem comprises a plug, and a stem-tail connected to the plug by a breakneck which is concealed by overlapping lips. The plug has a stop face, and an annular locking groove between the breakneck and the stop face. The body has a deformable locking collar upstanding above an adjacent region of the upper surface of the head. The diameter of the bore reduces, to provide a stop face and a locking region of smaller diameter, within the head. The fastener is set by pulling the plug into the bore until the stop faces meet, to form a blind head, and then deforming the collar to force the body to bulge into the locking groove of the plug.

Abstract: A three piece blind fastener of the kind comprising a tubular nut having a head at one end and a tapered nose at the other end, an expansible sleeve, and a headed bolt threadedly engaged with the nut for forcing the sleeve on to the nose of the nut to form a blind head, has the thread of the nut provided with a locking zone in which the bore of the nut is constricted and, in cross sectional shape, a closed non-reentrant non-circular curve so that the nut resiliently interferes with the bolt.A die, and a method of providing the nut with the locking zone by means of the die are disclosed. The die has a tapered aperture having a cross sectional shape corresponding to the desired shape of the locking zone, and the method involves forcing the tapered nose of the nut into the aperture so as to constrict the bore, in a zone spaced from its ends, to the desired extent and impose the non-circular cross sectional shape on the constricted zone.

Abstract: In a blind fastener (20) of the kind comprising a tubular nut (22) having a shank (28) with a head (30) at one end and a tapered nose (32) at the other end, a headed bolt (24) threadedly engaged in the bore (34) of the nut (22), and an expansible sleeve (26) which, by rotating the bolt (24), can be forced on to the nose (32) to form a blind head, a section of the shank (28) of the nut (22) is formed with a single protuberance (42) which protrudes resiliently into the bore (34) sufficiently to interfere with and restrain rotation of the bolt in the nut, and thus render the fastener self-locking. The shank (28) may have more than one section each provided with a single such protuberance (42), the effect of several protuberances being additive. Each protuberance (42) lies entirely within a minor sector of its section of the shank, and presents either a flat or a curved threaded surface traversed by the thread (38). Protuberances may be in different sectors if spaced longitudinally of the shank.

Abstract: A three piece blind fastener of the kind comprising a tubular nut having a head at one end and a tapered nose at the other end, an expansible sleeve, and a headed bolt threadedly engaged with the nut for forcing the sleeve on to the nose of the nut to form a blind head, has the thread of the nut provided with a locking zone in which the bore of the nut is constricted and, in cross sectional shape, a closed non-reentrant non-circular curve so that the nut resiliently interferes with the bolt.A die, and a method of providing the nut with the locking zone by means of the die are disclosed. The die has a tapered aperture having a cross sectional shape corresponding to the desired shape of the locking zone, and the method involves forcing the tapered nose of the nut into the aperture so as to constrict the bore, in a zone spaced from its ends, to the desired extent and impose the non-circular cross sectional shape on the constricted zone.

Abstract: An anchor nut fastener device is of the type comprising a tubular body portion (11) and a nut portion (12) which tapers externally, whereby when the body portion is inserted in a suitable hole in a workpiece and the nut portion (12) is forced into the body portion (11), the taper on the nut portion (12) both radially expands the body portion into engagement with the wall of the workpiece hole and also engages the nut portion in the body portion, thereby to provide an anchor nut in the workpiece. The external taper on the nut portion (12) comprises a first, relatively long, part (24) of a relatively shallow taper and a second, relatively short, part (26) of relatively steep taper further away from the body portion than is the first part and extending radially outwardly of the first part. The end of the body portion (11) is enlarged to provide a head (10), and a countersink (14) into which the leading end of the nut can be enlarged.