| 摘要 |
PURPOSE:To manufacture a product excellent in dimensional accuracy through a small number of working processes by swaging first a blank material so as to form a stepped part having the same dimensions as those of a product and then swaging the material in sequence into a product of prescribed dimenions basing on the stepped part. CONSTITUTION:An upper roll die 1 formed to have a stepped part of prescribed height (h1) and a lower roll die 2 formed to have that of prescribed height (h2) are rotated in a state of restricting their lateral movements, to process a blank material M into a rough shape material having the same width dimension WO, heights (h1), (h2), and corner parts A, B as those of the stepped part of a product by swaging the material from the upper and lower directions. Next the rough shape material is swaged in sequence to increase gradually its total width-dimension basing on the width dimension WO and heights (h1), (h2) thereby forming it into a product having the prescribed total width dimension W. In this way, the stepped part is prevented from generating shear droops at its corner parts A, B, and the dimensional accuracy of product is stabilized and improved, and also the number of working processes is reduced. |
