| 摘要 |
PURPOSE: A piercing method and a piercing apparatus are provided to obtain uniform cross section of connector pin, reduce asymmetry of the connector pin, particularly convexity and asymmetry of upper and lower surfaces of cross section of the connector pin, control displacement of the connector pin and improve productivity of piercing process. CONSTITUTION: The piercing method comprises a step of preliminarily shearing a part of thickness of a matrix(41); and a step of completely piercing a preliminarily sheared part(70) in the preliminarily sheared matrix(41). The piercing apparatus comprises a preliminary shearing punch(51) for preliminarily shearing a part of thickness of a matrix(41); a preliminary shearing punch guide block(52) that has a certain clearance with a matrix contact part and is adjacent to the punch; and a preliminary die(53) on which a shearing corresponding part(61) is formed in such a way that the shearing corresponding part that has a certain clearance with the matrix contact part and has depth corresponding to the part of thickness preliminarily sheared in the thickness of the matrix, wherein an elastic means is installed on an upper part of the preliminary shearing punch, and wherein depth of the shearing corresponding part of the preliminary die corresponds to 5 to 40% of thickness of the matrix.
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