Patent ID: 7575404

Claim:
A rivetless nut plate assembly which is configured for installation into an aperture of a composite material workpiece without risking delamination of the workpiece, said installation being effected by pulling a stem through the assembly, said rivetless nut plate assembly comprising: a nut; a holding bracket; a retainer which engages the holding bracket and retains the nut on the holding bracket; and a sleeve member which engages the workpiece and the holding bracket, wherein the sleeve member is made of a high strength and ductile material, wherein an outside or inside surface of the sleeve member has two chamfers, wherein the two chamfers comprise a first chamfer at a top of the sleeve member and a second chamfer at a bottom of the sleeve member, wherein the top chamfer is configured such that the sleeve member can accommodate upper angled surfaces of lobes which protrude from a base of the holding bracket, and the bottom chamfer is configured to function to accommodate a lip which is provided on an inside surface of the holding bracket, wherein the two chamfers on the sleeve member are provided to allow angled surfaces of the lobes and the lip room to expand within the sleeve member instead of within the composite structure workpiece.