Patent ID: 6453716
Filing Date: 2002-09-24
Classification: B21D,F16G

Abstract:
A method of blanking elements of a belt for use in a continuously variable transmission, each having a body and a head joined to the body by a neck, said body having a slanted surface tapered away from said head and a thin portion extending from said slanted surface toward an end of the body remote from said head, comprising the steps of:preparing an elongated metal sheet, a face side thereof which is flat, and a reverse side thereof having a flat central portion extending longitudinally and a pair of thin portions extending laterally from respective corners at edges of said flat central portion toward opposite edges of said elongate metal sheet; using element blanking punches to be applied to a face side of the elongated metal sheet which is placed on a die to blank elements having heads confronting each other across said elongated metal sheet out of two opposite sides thereof, and counter punches to be applied to the corners on the reverse side of the elongated metal sheet and movable with said element blanking punches to deform the corners of said elongate metal sheet under a counter load into slanted surfaces of the elements; determining averages of the differences between thicknesses at a measurement point on said elongated metal sheet at or near where said neck of said element is to be formed by blanking, and at a measurement point on said elongated metal sheet where said head of said element is to be formed by blanking; establishing a distance between the corners of said elongated metal sheet and said counter load in order to keep said averages in a predetermined allowable range; and blanking elements out of said opposite sides of the elongated metal sheet with the established distance between the corners thereof, with said element blanking punches and said counter punches under the established counter load.