Method for Producing a Gun Cartridge Casing

Abstract

The present invention relates to a novel method for producing a gun cartridge casing in a single multiple station deep drawing transfer press.

1 . A method for manufacturing a gun cartridge casing in a single multiple station deep drawing transfer press comprising the steps of:
 (a) providing a metal sheet to a multiple station deep drawing transfer press which comprises a blanking device for cutting blanks out of the metal sheet;   (b) cutting a metal blanket of said metal sheet;   (c) transferring said metal blanket obtained in step (b) to a first forming station which comprises a punch and a die, wherein said metal disc sheet is formed into a metal cup;   (d1) transferring said metal cup obtained in step (c) to a second set of forming stations comprising a number of punches and dies, wherein said metal cup is deep drawn into an cartridge case; and   (e1) releasing said cartridge case from the multiple station deep drawing transfer press,   wherein between steps (a) and (e1), there are no intermediate washing, pickling and/or bondering steps.   
     
     
         2 . A method for manufacturing a gun cartridge casing having a groove in a single multiple station deep drawing transfer press comprising the steps of:
 (d2) providing a metal cup to a set of forming stations in a multiple station deep drawing transfer press comprising a number of punches and dies, wherein said metal cup is deep drawn into a cartridge case; and   (e2) transferring said metal cup obtained from step (d2) to a further forming station comprising a punch and a die, wherein the diameter of the bottom of said cartridge case is reduced to the required groove diameter;   (f1) transferring said cartridge case having a bottom of reduced diameter obtained in step (e2) to a further forming station comprising a punch and a die to form a groove, wherein the die is a splitted die which can be opened after operation; and   (gi) opening the splitted die and releasing the cartridge case provided with a groove from the multiple station deep drawing transfer press,   wherein between steps (d2) and (gi), there are no intermediate washing, pickling and/or bondering steps.   
     
     
         3 . The method according to  claim 2 , comprising the steps of:
 (a) providing a metal sheet to a multiple station deep drawing transfer press which comprises a blanking device for cutting blanks out of the metal sheet;   (b) cutting a metal blanket of said metal sheet;   (c) transferring said metal blanket obtained in step (b) to a first forming station which comprises a punch and a die, wherein said metal disc sheet is formed into a metal cup;   whereupon the cup is transferred to step (d2), wherein between steps (a) and (gi), there are no intermediate washing, pickling and/or bondering steps.   
     
     
         4 . A method for manufacturing a gun cartridge casing having a neck in a single multiple station deep drawing transfer press comprising the steps of:
 (d3) providing a metal cup to a set of forming stations in a multiple station deep drawing transfer press comprising a number of punches and dies, wherein said metal cup is deep drawn into a cartridge case; and   (e3) transferring said cartridge case obtained in step (d3) to a further forming station, wherein said cartridge case is provided with a neck;   (f2) and releasing the cartridge case from the multiple station deep drawing transfer press,   wherein between steps (d3) and (f2), there are no intermediate washing, pickling and/or bondering steps.   
     
     
         5 . The method according to  claim 4 , comprising the steps of:
 (a) providing a metal sheet to a multiple station deep drawing transfer press which comprises a blanking device for cutting blanks out of the metal sheet;   (b) cutting a metal blanket of said metal sheet;   (c) transferring said metal blanket obtained in step (b) to a first forming station which comprises a punch and a die, wherein said metal disc sheet is formed into a metal cup;   whereupon the cup is transferred to step (d3), wherein between steps (a) and (f2), there are no intermediate washing, pickling and/or bondering steps.   
     
     
         6 . A method for manufacturing a gun cartridge casing having a neck in a single multiple station deep drawing transfer press comprising the steps of:
 (d4) providing a metal cup to a set of forming stations in a multiple station deep drawing transfer press comprising a number of punches and dies, wherein said metal cup is deep drawn into a cartridge case; and   (e4) transferring said cartridge case obtained from step (d4) to a further forming station comprising a punch and a die, wherein the bottom of said cartridge case is reduced to the required groove diameter;   (f3) transferring said cartridge case provided with a reduced bottom obtained in step (e2) to a further forming station comprising a punch and a die to form a groove, wherein the die is a splitted die which can be opened after operation; and;   (g2) opening the splitted die and transferring said cartage case provided with a groove obtained in step (f2) to a further forming station, wherein said elongated metal cup is provided with a neck; and   (h1) releasing the cartridge case from the multiple station deep drawing transfer press wherein between steps (d4) and (h1), there are no intermediate washing, pickling and/or bondering steps.   
     
     
         7 . The method according to  claim 6 , comprising the steps of:
 (a) providing a metal sheet to a multiple station deep drawing transfer press which comprises a blanking device for cutting blanks out of the metal sheet;   (b) cutting a metal blanket of said metal sheet;   (c) transferring said metal blanket obtained in step (b) to a first forming station which comprises a punch and a die, wherein said metal disc sheet is formed into a metal cup;   whereupon the cup is transferred to step (d3), wherein between steps (a) and (h1), there are no intermediate washing, pickling and/or bondering steps.   
     
     
         8 . The method according to  claim 1 , wherein the metal sheet is of brass. 
     
     
         9 . The method according to  claim 1 , wherein said multiple station deep drawing transfer press comprises 12 to 25 pairs of punches and dies in total. 
     
     
         10 . The method according to  claim 1 , wherein said third set comprises three to five pairs of punches and dies for carrying out step (e). 
     
     
         11 . The method according to  claim 1 , wherein said multiple station deep drawing transfer press develops a press force between 75 and 250 tons. 
     
     
         12 . The method according to  claim 1 , wherein said multiple station deep drawing transfer press has a bed length between 1000 and 3000 mm. 
     
     
         13 . The method according to  claim 1 , wherein said multiple station deep drawing transfer press comprises a servo spindle press which actively corrects punch wrinkling. 
     
     
         14 . Multiple station deep drawing transfer press for manufacturing a gun cartridge casings in a single machine, which comprises a cutting device for cutting discs out of the metal sheet and a number of pairs of punches and dies for drawing said metal discs, wherein in at least one pair of a punch and a die, the die exhibits a splitted punch to form a groove. 
     
     
         15 . The method according to  claim 9 , wherein said multiple station deep drawing transfer press comprises 15 to 25 pairs of punches and dies in total.