| 摘要 |
PURPOSE:To reduce the irregularity, at the cutout end face, to be caused by a secondary cutting operation of individual thin leads by a method wherein a lead tie bar supports two or more leads at a part other than their end part and individual end parts are kept open. CONSTITUTION:Each unit frame 1 is coupled in a row by using a coupling piece 3; the unit frame 1 contains an island 7 and individual leads 2 which have starting edges 22 near the circumference of the island 7. In addition, the unit frame 1 contains a support material consisting of the following: an island tie bar 5 connecting the island 7 to the coupling piece 3; tie bars 6 connecting an arbitrary lead 2 to an adjacent lead 2 or to the coupling piece 3; a part of the coupling piece 3. This part of the coupling piece is formed actually as the one-piece belt-like coupling piece 3. An end part 21 of each lead 2 is formed by a first stamping process in such a way that it is separated from all other materials including its adjacent lead. By this setup, the irregularity of the shape of the cutout end face at each cutout lead 2 is prevented.
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