Patent ID: 7762751

Claim:
A self-drilling anchor for use in a friable material, comprising: a body having an axis, a flanged rear end having torque transmitting surfaces, a drilling front end, an outer surface with a thread having a height sufficient to increase pullout strength disposed thereon, a first leg and a second leg; said self-drilling anchor having a drilling mode wherein said first leg and said second leg form a generally cylindrical portion, said first leg has a generally rearward facing shoulder angled obtusely with respect to said axis and outwardly toward the drilling front end, said body has an axial bore for receiving an elongate fastener, said axial bore having a sidewall and extending substantially through said flanged rear end and leading axially uninterruptedly to said generally rearward facing shoulder, said first leg and said second leg are demarcated from one another by at least one slit beginning at a predetermined distance from said flanged rear end and extending at least partly through said outer surface and said thread of said generally cylindrical portion; wherein said axial bore has an end surface between said sidewall and said generally rearward facing shoulder; wherein said self-drilling anchor is adapted such that said first leg pivots apart from said second leg when said elongate fastener deflects said generally rearward facing shoulder; and wherein said predetermined distance is between about 1/16 inch and about ⅜ inch and said generally rearward facing shoulder is angled between about 100° and about 170° with respect to said axis.