PROBLEM TO BE SOLVED: To improve stretch flange formability of a processed material by a punching device having an inclined cutting blade.;SOLUTION: The punching device 15 with a shear angle is provided with a punch 2 having an upper cutting blade 10 inclined to a cutting-plane line direction and a die 3 having a lower cutting blade 3a. A partial plate reverse presser foot 12 for pressing part of the processed material 1 after part of the processed material 1 is cut, is provided in the position opposing to the punch 2. The partial plate reverse presser foot 12 is arranged below part or all of a stretch flange projected part in forming after cutting of the processed material 1.;COPYRIGHT: (C)2009,JPO&INPIT
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