Process for manufacturing monobloc vehicle wheels

The process of manufacturing monobloc metal vehicle wheels including a central disc portion comprising a large and small flange area, a rim portion for pneumatic tires, and a junction zone between said disc and rim portions, said process comprising a shaping step beginning with a roughly shaped article in the form of a cylindrical disc and a finishing step involving mechanical machining wherein the shaping is effected by a combination of die stamping and press widening operations consisting of the following steps:

• a first die stamping step producing the wheel disc and simultaneously forming on its circumference a junction zone terminating in a thickened bead oriented in a direction substantially parallel to the axis of the wheel and the inner side of the wheel to define one part of the rim portion;
• a second die stamping step elongating said bead and said junction zone in the same general direction as in the preceding step and simultaneously forming the rough shape of a small flange portion of the rim on the bead adjacent the junction zone;
• a third die stamping step forming the small flange to a shape approximating its final form and simultaneously elongating the junction zone and the bead in the same direction as in steps one and two imparting thereto a length substantially equal to the final length of said junction zone and said bead to define the large flange portion of the rim;
• and a press widening of the elongated bead to a shape from which said large flange may be machined to finished form.