A METHOD AND TOOL FOR PRODUCING A BUSHING STRUCTURE HAVING A POLYGONAL FLANGE

摘要

The invention relates to a method and a tool (6,8) for producing a bushing structure (1,2) having a bushing (1) and a polygonal flange (2) said flange initially being formed with a circular circumference (5) having an outer diameter equalling the diameter of the inscribed circle (5) of the polygon to be made whereafter by means of cold deformation the material of the flange at the location of the angles of the polygon to be made is forced to flow outwards by means of a die (8) having projections (9) the inner surfaces (10) of which are steep with respect to the axis of the die and the bottom surface (11) of which run obliquely and arching by upwards and outwards the radial width of said projections decreasing from the center to both sides.