Patent ID: 9322424
Filing Date: 2016-04-26
CPC Classification: F16B

Claim Text:
1. A stud for attachment to a plastically deformable metal substrate, said stud comprising: a body portion with a central axis and a punch portion extending from said body portion and coaxial with said central axis, said body portion including an annular-shaped surface encircling the central punch portion, said annular-shaped surface including a plurality of spaced apart lugs encircling the central punch portion, one of the lugs including at least a contact surface with a recessed portion wherein the contact surface engages said metal substrate, a first portion of the contact surface being biased in a rotational direction about the central axis upon insertion in the metal substrate to form at least one lug flare during attachment of said stud to said metal substrate; and an integrally formed threaded shaft extending from said body in a direction away from said metal substrate, upon insertion into the metal substrate a portion of the metal substrate being entrapped between the at least one lug flare and the body portion, wherein the recessed portion has a larger width at a location radially closer to the punch portion than at a location radially further away from the punch portion.