METHOD FOR THE COLD EXTRUSION OF BOLTS, IN PARTICULAR FOR FASTENING THE CUTTING BLADES OF MOWERS OR THE LIKE

摘要

A method for producing metal parts such as special bolts (20) by means of cold extrusion in pressing dies comprises a first step of cutting to size a metal blank (30) to be modelled with predetermined dimensions, at least one step of cold pressing in a die in order to reduce one or more portions of the blank (30) to predetermined diameters, and a step of cold pressing in a die during which a coupling key (25) is formed on a portion (32) of the blank (30), the lateral surface (36) of the key protruding beyond the lateral surface of this portion (32), with respect to the longitudinal axis of the blank (30). The resulting product can be used in particular as a special bolt for the positive coupling of a mowing machine blade to a rotating plate in order to rotate the blade.