GB1350890A - Shell trimmer - Google Patents

Abstract

1350890 Shearing DAYTON ROGERS MFGCO 22 Dec 1970 [12 Jan 1970] 60828/70 Heading B3W A shear for trimming a shell S has dies 18, 19 relatively movable for assembly and disassembly with a shell S, the die holder 20 being stationary during shearing and the die holder 17 being moved transversely and orbitally to trim the shell by engagement of a crank 26 eccentrically mounted on a rotor 27 with a socket 25 mounted in a rotary bearing 24. The holder 17 is retained between plates 16 and 23, springs 34 space the assembly 16, 17, 23 from a stationary head plate 12 and a sleeve 35 guides its movement to and from the plate 12. The holder 17 is centred relative to the motor 27 by engagement of a cylindrical end portion 30 of the crank in a complementary portion 33 between frusto-conical surfaces 31, 32 of socket 25 which are concentric with the axis 28 of the rotor 27. The frustoconical upper portion 29 of the crank 26 conforms to the surface 31 of the socket and the lower flared portion conforms to the surface 32. In operation, the die holder 20 is raised hydraulically until the die 18 engages the base of the shell. Further upward movement of the die holder 20 compresses the springs 34 and moves the socket 25 up the crank 26, the camming action of the frusto-conical surface 31 with the crank portion 29 causing orbital movement of the die holder 17 and shearing of the shell edge. As the crank is withdrawn from the socket after shearing, the frusto-conical surface 32 causes the reverse movement of the die holder 17. The trimmed shell is ejected by an air blast through line 21. In an alternative embodiment, Fig. 3 (not shown), the rotor shaft (14<SP>1</SP>) is surrounded by a single spring (34<SP>1</SP>) and mounted in a conventional drill press, the head plate assembly (12<SP>1</SP>) &c. and rotor being moved downwardly to carry out the shearing operation.