Patent attributes
A low swage load fastening system is provided for installing swage-type fasteners to secure a plurality of workpieces together. The fastener includes a pin member, having an elongated pin shank to be located in aligned openings in the workpieces. An enlarged head at one end of the pin engages one side of the workpieces. A grooved pin portion extends past an opposite side of the workpieces. A collar includes a shank portion adapted to be swaged into the pin lock grooves in response to a relative axial swage load applied by an installation tool. As one aspect of the system, the collar is as-headed and does not require thermal processing yet provides an optimum balance of reduced collar shank wall thickness and increased hardness, whereby the swage load is minimized. A low swage load thread form for the lock grooves of the pin is also provided, a reduced diameter, relatively short pull portion pin extension, installation tool improvements, and an associated method of use are also disclosed. The collet has a protrusion from said collet thereby extending the length of the pull section in a direction towards the collar thereby to increase the contact area with said anvil. The end of the pull is not rolled down to a diameter position in line with the base of the groove thereby to increase the shear strength of the end pull crest of the pull. The last pull crest of the pull have a contour to conform with an enlarged puller radius of the last tooth of the collet.
