MOLD STRUCTURE AND CUTTING METHOD FOR CUTTING LEAD FRAME USING SHEET CUTTING SHEET AND MANUFACTURE OF CUTTING SHEET

摘要

PROBLEM TO BE SOLVED: To form a mold structure at a low cost, to facilitate exchange of a cutting edge part, and to position a cutting edge part with high precision without needing a special techniques. ;SOLUTION: Since a sheet-form cutting sheet 1 has cutting edge parts in the same shape as each other on an upper and an under surface, exchange of the cutting edge part is practicable only by turning over the upper and the under surfaces. Further, a cutting sheet 1 guides a guide part 7 to the guide groove 11 of a bottom mold die body 2 and positioning in a longitudinal and lateral directions is effected by holding the right and the left by a side plate 14. By connecting a suction pipe 21 to a vacuum source, the cutting sheet 1 is sucked and supported at the bottom mold die body 2 side through a passage formed in the lower mold die body 2. With this state, by inserting a punch for the upper mold die in a dam pull edge part 3, a tie bar cut edge part 4, and the cut edge part 5, cutting by the tie bar is effected to form a lead frame in a desired shape.;COPYRIGHT: (C)1997,JPO