Patent ID: 7740569
Filing Date: 2010-06-22
Classification: A63B

Abstract:
1. Weight-lifting apparatus comprising: a) an elongated shaft having threaded ends, a centrally located handle, a tapered spline adjacent each of said threaded ends and having a series of uniformly spaced ridges on the shaft that are parallel to its axis, a collar between said handle and each spline, and a tensile strength greater than 110,000 psi; b) two heads having a tensile strength less than 110,000 psi, each of said heads having a first opening on its inner face and a second opening on its outer face and mounted to each end of said shaft forcing the spline into the first opening of each of the heads to create grooves within the heads that correspond to ridges of the spline with substantially no deformation of the shaft during assembling because of the tensile strength differential between the shaft and the heads, resulting in the apparatus having heads that after being compressed due to severe shock loads and heavy commercial use are prevented from rotating on the shaft because of an interference between the splines and the heads; c) a nut within the second opening of each of the heads and threadably fastened to each of said threaded ends of said shaft; and d) whereas the resulting apparatus has heads that after being compressed due to severe shock loads and heavy commercial use are prevented from rotating on the shaft because of the interference between the spline and the heads and even after the nuts are removed, the heads will not rotate; said shaft and said heads are constructed of a metal selected from the group consisting of steel, cast iron and mixtures thereof.