Patent ID: 6233999
Filing Date: 2001-05-22
Classification: B21D

Abstract:
A method for forming two sets of spline teeth on a sheet metal article by ironing said sheet-metal article between a forming die, and a forming punch, wherein said sheet metal article has a smaller and a larger diameter portion connected by a stepped portion and said two sets of spline teeth are formed on said smaller and larger diameter portions, respectively,and said punch includes a first punch for coacting with the smaller diameter portion of said sheet metal article, and at least one second punch which is disposed coaxially with respect to the first punch and is separately movable with respect to said first punch for coacting with the larger diameter portion of the sheet-metal article, comprising the sequential steps of:(a) moving the second punch into pressurized engagement with said larger diameter portion of said article to iron a set of spline teeth on said larger portion, and(b) moving the first punch into pressurized engagement with said smaller diameter portion of said article to iron a set of spline teeth on said smaller portion,wherein said second punch remains in pressurized engagement with said larger diameter portion during step (b) so as to lower an inflow of sheet metal material into the step portion.