Patent ID: 7874777

Claim:
An attachment device for joining at least two elongated planar metal members having adjacent planar surfaces in contact with each other and their remote planar surfaces facing away from each other, said attachment device comprising: a tapered passage having a pre-selected taper extending through said metal planar members from one of said remote planar surfaces to the other of said remote planar surfaces, an elongated tapered metal sleeve having an external taper corresponding to said taper of said tapered passage with said tapered metal sleeve positioned in said tapered passage with the larger and smaller diameter ends of said tapered sleeve located beyond said remote planar surfaces of said metal members, an elongated headed fastener extending through said tapered metal sleeve, said fastener having a threaded portion located at its end opposite to said headed portion with said headed portion positioned adjacent said larger diameter end of said tapered sleeve and said threaded portion positioned adjacent said smaller diameter portion of said tapered metal sleeve, a bearing washer located between said headed portion of said fastener and said remote planar surface of planar member with said bearing washer engaging said tapered sleeve, a spacer washer surrounding said tapered sleeve and positioned between said bearing washer and said remote planar surface of said planar metal member to limit movement of said bearing washer against said tapered sleeve, a nut fitted on said threaded portion of said headed fastener, and a spacer washer located between said nut and said smaller diameter end of said tapered sleeve to prevent said nut from engaging said smaller diameter end of said tapered sleeve when said nut is fitted on said threaded portion of said headed fastener.