GB677745A - Improvements in or relating to the manufacture of crown stoppers for containers - Google Patents

Abstract

677,745. Making crown stoppers. CROWN CORK CO., Ltd., and BECK, N. Feb. 28, 1951 [Feb. 28, 1950], No. 5118/50. Classes 83 (ii) and 83 (iv). Stamping.- A machine for making crown stoppers for containers of the type in which sheet stock is fed between opposed tubular dies one of which is movable and has its cutting edge on its outer circumference, the other stationary die having its cutting edge on its inner circumference is characterized in that corrugation-forming serrations are located on the movable cutting die or on a member nested therein and the said movable cutting die is directed against that face of the blank which will be the upper face of the finished crown when the crown is in position on the top of the container. A machine according to the invention comprises an upper slide 12 reciprocated by a cam-operated rod 13 and a lower slide 14 similarly reciprocated by a rod 15. A cylindrical plunger 16 is nested in a tubular blank cutting-die 17. The plunger is pinned to a rod 18 adjustably attached to the slide 12 and the die 17 is adjustably connected to the slide 14. The die has its cutting edge on its outer circumference and co-operates with a stationary tubular cutting die 22 supported on a holder 24 on a table 11. Longitudinal adjustment of the die is effected by shims 26. A backing ring 25 inside the holder 24 screws on to a support 27 which passes through the table 11, the support being locked by a ring 28 clamped to the table. Inside the die 22 and located opposite to the die 17 is a spring-loaded tubular ejector 33. Corrugation-forming serrations 38 are located on the die 17 and inside the plunger 16 is a spring-loaded ejector 39. Surrounding the die 17 is a spring-loaded stripper 42. In operation, the slides 12 and 14 are timed so that the plunger 16 and the head 35 grip the work and the die 17 moves into the die 22 so cutting out the blank and drawing the edge of the blank around the head 35 and simultaneously forming the corrugations. In an embodiment a single slide 45, Fig. 4, replaces the slides 12 and 14 and the bore of the rod 18 extends through to the top of the rod where it is closed by a plug 47 against which a spring 41 abuts. The slide operates the die 17 and also the plunger 16 through a resilient connection comprising a pillar 48 on the slide and two bearing plates 49, 50 having a spring 51 between them. Thus, when the work is gripped between the plunger and the head 35 the plunger ceases to move but the die 17 continues its movement and forms the stopper. The serrations 38 may be formed on an extension 52 of the perimeter of the plunger 16, Fig. 5. Alternatively the serrations may be on a detachable surround mounted on the plunger or on a detachable insert 54, Fig. 7, nested in the die 17. Specification 659,200 is referred to.