GB789489A - A press for providing semi-finished cartridge cases with an extraction rim - Google Patents

Abstract

789,489. Forging presses. LIBERGELD, M. Feb. 17, 1956 [Feb. 28,1955], No. 4976/56. Class 83(4). A press for providing a cartridge case 10 with a rim 9 comprises a mandrel 11 and jacket die 17 co-operating with a counter-die 4, 8 to provide an annular space into which the cartridge base is upset to form the rim. The counter-die comprises a ring die 8 provided with the undercut recess 8a and a bottom die 4 slidable within the bore of the ring die and adapted to be locked in the pressing position by a ram 5. The mandrel 11 is mounted on a movable press ram 12 on which is screwed a sleeve 14 which carries the jacket die 17. The latter is supported against a shoulder 14b of the sleeve through a spring 18. In operation, a cartridge blank is inserted over the mandrel which is moved forwardly with the jacket die to press against the base of the cartridge and upset the metal to form the rim. During initial retraction of the mandrel, the spring 18 maintains the jacket die 17 in contact with the ring die 8 to hold the cartridge 10 in the ring die and hence release it from the mandrel. The ram 5 then moves the bottom die 4 forwardly to eject the cartridge. A stripping ring 19 frictionally mounted on the mandrel has ears 19a projecting through longitudinal slots 14a in the sleeve 14. If the cartridge 10 adheres to the mandrel when the latter is retracted, the open end of the cartridge moves the ring 19 into engagement with a resilient buffer 20 which is moved to engage a stopmember 23, Fig. 4 (not shown), for stopping the press. The stop-member may be electrical, mechanical or hydraulic according to the type of press used.