METHOD AND APPARATUS FOR WORKING COVER OF SHEET METAL Russian patent published in 1998 - IPC

FIELD: equipment and processes for working sheet-metal cover of tinned cans for drinks. SUBSTANCE: at working sheet metal cover, mainly of cans for drinks, annular zone of front surface of cover radially adjoining to radius portion between said front surface of cover and rod flute is pressed out in such a way that material of said zone is displaced radially outside through adjoining radius portion. It is achieved due to use of pressing out surface tapered radially outside and upwards and acting upon front surface of cover from outside. Apparatus includes upper and lower parts of pressing out die set. Lower part of die set has slope with annular rib. Spacing in direction normal relative to direction of annular strip zone between surface of said rib and surface of lower part of die set increases radially outside and radially inside in such a way that material practically may not be displaced in that direction. EFFECT: enhanced efficiency of method, improved design of apparatus. 10 cl, 5 dwg