APPARATUS FOR PUNCHING BOTTOM OF SLEEVE TYPE BLANK WITH SMOOTH ROUND INNER CYLINDRICAL SURFACE Russian patent published in 2001 - IPC

FIELD: machine engineering, namely plastic metal working. SUBSTANCE: apparatus for punching bottom of sleeve type blank includes die with through cylindrical cavity for placing blank and punching ring having annular step portion near outlet end of cylindrical cavity. Die has outer cone surface coaxial relative to surface of cylindrical cavity. Die is placed in holder with cone opening whose conicity degree is equal to that of outer surface of die. Apex of cone surface of mutual joining of die and holder is arranged at outlet side of die. Conicity angle is equal to 8-12 degrees. At side of die end with less outer diameter limiter of axial shifting of die is mounted in holder. After punching bottom and unloading tool, blank is self-pressed out. It decreases hazard of jamming blank in die after termination of bottom punching process. EFFECT: possibility for simplified free extraction of blank without friction. 2 cl, 2 dwg