A ROUND METAL ROD SECURED TO A METAL PLATE

摘要

A metal rod having a radial flange formed at one end and space pointed projections formed on the underside of the flange is inserted through a round hole in a metal plate. The metal rod plate combination is placed in a press on a bottom die having an axial insertion hole and an annular step formation of alternate grooves and ridges on the top surface of the bottom die round the insertion hole. Under pressing force, metal of the metal plate in its region around the bottom edge of the round hole is extruded radially inwardly against the neck portion of the flanged metal round rod under the effect of the step formation on the bottom die while at the same time the projections are driven into the surface of metal plate. The resulting metal assembly exhibits substantially improved adhension and torsional resistance between the metal members.