Wheel nut assemblies

Claim 1

A wheel nut adapted to bear against a flat work surface and comprising an internally threaded nut body and a seating washer, the nut body having a convex bearing surface and the washer a cooperating concave seating surface, both said surfaces being spherical in character whereby to allow freedom of movement between said nut body and said washer as the nut body is moved from an initial to a tightened condition to accommodate misalignment of a cooperating stud disposed nominally perpendicular to said flat surface; said washer having a substantially centrally-disposed opening for receiving the stud, a flat bearing surface for continuous flat bearing engagement with the flat work surface along the entirety of said bearing surface, a continuous peripheral sidewall extending between said flat bearing surface and said concave seating surface, and a solid cross-section between said bearing surface and said seating surface and between said centrally-disposed opening and said peripheral sidewall, said washer being formed of softer material than said nut body and having its seating surface initially in contact with the nut body at the outer periphery of said surface and in the tightened condition of the nut body making contact over its whole area by virtue of elastic deformation of the washer.