Patent ID: 8425167

Claim:
A fastener assembly adapted for welding to a first workpiece and then mechanically securing a second workpiece to the first workpiece, the fastener assembly comprising: a weld stud including: a bolt portion formed with a male threading, a weld end weldable to the first workpiece; a shank located between the bolt portion and the weld end; the shank including a conical surface tapering radially outward to a first diameter in the axial direction of the weld end; the shank further including a neck portion located between the conical surface and the weld end, and having a second diameter less than the first diameter; and a nut member including a tubular body further including an outer polygonal surface and an internal female thread; a plurality of pressing pieces having predetermined lengths located at intervals around an outer periphery of the nut member, the pressing pieces including tips, the tips being proximate to the weld end of the stud bolt; the nut member being tightened on the bolt portion, via the nut member internal female threads and the bolt portion male threading, against the second workpiece; wherein the pressing pieces contact the conical surface and are splayed radially outward and contact the second workpiece; and wherein the pressing pieces are deformed to tangentially engage the second workpiece such that substantially the entire lengths of the pressing pieces extend radially outward beyond the first diameter of the conical surface so that the second workpiece is supported by uniform compressive strength against the first workpiece.