SHOCK ABSORBING STEERING SHAFT AND PRODUCTION METHOD

摘要

PURPOSE:To produce a steering shaft at a low cost and improve the shock energy absorbing characteristic by displacing the insertion section of an inner shaft in the direction of the cross section of rotation in relation to the molded section. CONSTITUTION:An inner shaft 1 is formed in a hexagon shape at the cross section of rotation, an outer cylindrical member 2 is a cylindrical body slidably receiving the hexagonal inner shaft 1, and a round bar member 3 with a circular cross section is inserted at its upper end and is fixed by welding. The outer cylindrical member 2 located at the end of the insertion section of the inner shaft 1 is formed along the hexagonal shape of the inner shaft 1 by press-caulking. The inner shaft 1 is extracted from the press-caulked section, the insertion section of the inner shaft 1 is displaced by 90 deg. in the direction of the cross section, and the outer cylindrical member 2 is press-caulked along the hexagonal shape of the inner shaft 1.