| 摘要 |
PURPOSE:To absorb stress by a bendable section, to prevent the remaining of stress in a lead formed in three dimensions and to improve the precision of the solid lead by shaping the bendable section when a stage-lead forming scheduled section is formed to a base shape. CONSTITUTION:The four corner sections of a plane-shaped stage-lead forming predetermined section 9A after stamping are connected to frame bodies 7, 8 by bent bars 10-13 having thin width. The predetermined section 9A is formed to a base shape toward an upper section through fabrication, a peripheral section is drawn near to the center with the formation of the base-shaped section, bent bars 10-15 are bent and absorb stress, and a stage-lead forming prearranged section 9 is formed to the base shape under the state in which stress is not left. The base-shaped section is stamped, one end sides 6a of leads 6, a stage 3 and sections near to the stage 3 of support bars 4, 5 are shaped, and the support bars 4, 5 are fabricated. One end sides 6a of the leads 6 are shaped by punching the base-shaped section, and each lead 6 is formed under the state in which residual stress is removed. |
