Abstract: Blind fastening means for fastening thin materials together without crushing them. Such means comprises a blind rivet sleeve, a blind rivet pin provided with a head to engage the blind end of the sleeve, and spacing means provided intermediate the blind end of the sleeve and the head thereof. As the head of the pin is drawn against the blind end of the sleeve an enlarged blind head forms at the blind side of the materials being fastened while the spacer means engages the interior side of the uppermost of the materials being fastened whereby to prevent crushing of such materials. In one instance the spacer means comprises a spacer sleeve. In a modification the spacer means comprises a second enlarged blind head. The various enlarged blind heads may be achieved in several ways.

Abstract: Blind fastening means for fastening thin materials together without crushing them. Such means comprises a blind rivet sleeve, a blind rivet pin provided with a head to engage the blind end of the sleeve, and spacing means provided intermediate the blind end of the sleeve and the head thereof. As the head of the pin is drawn against the blind end of the sleeve an enlarged blind head forms at the blind side of the materials being fastened while the spacer means engages the interior side of the uppermost of the materials being fastened whereby to prevent crushing of such materials. In one instance the spacer means comprises a spacer sleeve. In a modification the spacer means comprises a second enlarged blind head. The various enlarged blind heads may be achieved in several ways.

Abstract: A blind rivet comprising a sleeve with a preformed rivet head at one end, and a setting pin telescoped into the sleeve and having a pulling section projecting beyond the headed end of the sleeve and an expanding head projecting beyond the other end of the sleeve, to be pulled into the sleeve from the headed end thereof to expand the other end of the sleeve into a bulb-shaped rivet head against one side of two workpieces that are to be riveted together, the pulling section being broken off after the rivet is set, in response to engagement of the expanding head with stop means in the sleeve. The expanding head has an expanding shoulder for initiating expansion of the sleeve, and a taper beyond this shoulder which progressively increases the diameter of the head toward its free end.

Abstract: The method and means for installing blind fasteners involves a pulling head design such that will cause the stem of the rivet pin to be broken at a predetermined location by a trimming or notching action of the head. This allows a previously unweakened blind fastener pin to be weakened for breaking at a prescribed location after the fastener is installed, thus accomplishing a pin break off substantially flush with the head of the fastener over an extremely wide range of thickness and types of materials being fastened. The pulling means may include a support housing which slidably receives a chuck assembly for pulling the blind rivet pin. A collet is also mounted in the support housing. The collet has suitable cutting edges for weakening the pin stem immediately adjacent the head of the rivet sleeve when appropriate load forces are reached. Cooperating cam surfaces on the support housing and collet react to the load forces to effect this weakening action.