Patent ID: 7040131
Filing Date: 2006-05-09
Classification: B21H,Y10S

Abstract:
1. A cold forming tool having a forming reference axis and a plurality of regularly-spaced teeth with tips wherein the plurality of regularly-spaced teeth project away from an outer surface, the cold forming tool comprising: at least one penetration zone defined by the forming reference axis and comprising some of the plurality of regularly-spaced teeth; a calibration zone following the at least one penetration zone; the calibration zone defined by the forming reference axis and comprising some of the plurality of regularly-spaced teeth; the plurality of regularly-spaced teeth having a tooth height that increases substantially from the at least one penetration zone to the calibration zone; a distance between the outer surface and the forming reference axis decreasing from the at least one penetration zone to the calibration zone; and a rate of increase in the tooth height between the at least one penetration zone and the calibration zone being greater than a rate of decrease in the distance between the outer surface and the forming reference axis between the at least one penetration zone and the calibration zone, whereby a distance between the tips and the forming reference axis increases substantially from a beginning of the at least one penetration zone to a beginning of the calibration zone, wherein the cold forming tool is adapted to form a part by rotating the part and ensuring that the part has substantially no axial displacement.