Method of installing drive nut blind fasteners with cap nuts

摘要

A blind fastener is provided for connecting two workpieces together, comprising an internally threaded fastener body and an externally threaded stem passing in threaded engagement therewith. A drive nut is mounted on the stem in contact with the fastener body for preventing rotation thereof upon turning of the stem to install the fastener. The outer end of the stem has a cap nut to enable turning of the stem. Both the drive nut and cap nut are engaged by wrench components of an installation tool to cause turning motion of the stem relative to the fastener body to deform a sleeve around the fastener body into contact with one surface of the two workpieces. Although the fastener may vary in size depending upon the nature of the two workpieces to be connected together, the outer dimensions of the drive nut and cap nut remain constant for all fasteners regardless of differing stem diameters of different size fasteners. This enables setting fasteners of different stem diameters without necessity to change the wrench components of the installation tool. The outer surface of the drive nut and cap nut may be hexagonal or cylindrical in configuration for use with either hand held or robotic installation tools.