Patent ID: 6745453
Filing Date: 2004-06-08
Classification: B21H,F16D,Y10T

Abstract:
A rim rolling method which operates on a metal blank, the metal blank having an outer peripheral portion and a thickness, the method comprising the steps of:forming a groove having a width that is larger than the thickness of the metal blank in an outer peripheral face in a circumferential direction of a preforming roller die, and in which a groove forming blade portion protrudes in the circumferential direction on an inner bottom portion of the groove; pressing the preforming roller die with the groove and the groove forming blade portion against the outer peripheral portion of the metal blank to form an outer peripheral groove in the entire outer peripheral portion of the metal blank by the groove forming blade portion; and pressing an expanding blade portion of an expandingly forming roller die, which expanding blade portion protrudes from an outer peripheral face in a circumferential direction, against the outer peripheral groove of the metal blank, whereby a rim is expandingly formed while slitting the outer peripheral portion of the metal blank into two parts in the thickness direction.