PIERCING UNIT FOR FORMING PIERCING HOLE IN METAL STRIP AND, METHOD FOR PIERCING

摘要

PURPOSE: A piercing unit for forming a piercing hole on a metal strip and a method for piercing are provided to improve a response rate even when a size of a height adjustment member is big. CONSTITUTION: A piercing unit for forming a piercing hole on a metal strip comprises a plurality of piercing punches, a height adjustment member(140), and a rotating member. A pair of the piercing punches accomplishes a designated angle based on a circle. One upper end of the piercing punches is corresponded to grooves(144,146) according to the forward rotation of the height adjustment member. The upper end of the rest one is not corresponded to the groove. The piercing hole is formed in the metal strip by using the piercing punch which is not corresponded to the groove.