GB771639A - Improvements in combined forging and trimming method and apparatus - Google Patents

Abstract

771,639. Forging; trimming. NATIONAL LEAD CO. June 24, 1955 [July 8, 1954], No. 18307/55. Class 83 (4). A method of forging metal articles and trimming the flash therefrom, comprises forging a heated metal slug into a shaped article in a forging die A, B, and then trimming in a trim die having upper and lower parts 19, 17 respectively, the flash from the forging, the upper part 19 of the trim die being evacuated during the trimming operation so as to retain the trimmed forging therein during its upstroke, the trimmed forging being subsequently ejected from the upper part by an ejector 22. The stationary lower part B of the forging die receives a heated slug whereupon the upper die A is closed thereon and a forging ram 13 actuated by a pneumatic plunger 14 is moved upwardly to upset the slug into the closed die cavity, flash being produced at the joint between the die halves. On the upstroke of the upper die, the forging is retained therein and is subsequently ejected therefrom by an ejector 11 actuated through rack-and-pinion mechanism, Fig. 3 (not shown), by an hydraulic motor. The ejected forging drops into the lower trim die 17 which is mounted on a slide 15 movable by a motor 16. The slide 15 is then withdrawn to position the lower trim die 17 into alignment with the upper trim die 19 which is subsequently lowered whereby its shearing edge 20 severs the flash whilst the forging is still hot, simultaneously depressing a spring-loaded stripper ring 25. During the trimming the upper die 19 is evacuated through a port 21 so as to retain the forging therein during the upstroke. The flash is removed from the lower die 17 by the stripper ring 25 and is blown clear by an air blast. The trimmed forging may be cooled by a stream of air, or may be permitted to cool naturally, whilst in the upper trim die and is then removed therefrom by the ejector 22 actuated by an hydraulic motor. Meanwhile the slide 15 has moved inwardly so that the ejected forging drops into a shoot 18 carried by the slide. Alignment means 23, 24 are provided for the trim die. The various movements of the apparatus are performed automatically in the correct sequence including the retraction of the forging ram 13.