Patent GB-287769-A (GB)
Title: Improvements in or relating to manufacture of hot cut nut blanks
IPC: B21K1/64
Filed: 1927-08-02
Abstract: 287,769. Golding, J. F. Aug. 2, 1927. Nuts.-Nut blanks are formed from metal slugs &c. by heating the metal until sufficiently soft to cut smoothly cutting along all the vertical sides of the nut blank and removing the exterior trimming to form the smooth nut sides, and cutting the metal from the middle of the blank to form a smooth perforation whilst the metal is restrained by the side cutting means. The slugs are supplied by an automatic selecting and delivering machine B to a furnace A and conveyed by a conveyer a to a shoot c and thence by gravity to the bed 1 of the shaping and perforating press C. The crosshead 1 of the press, which is cam actuated in the usual manner, has a die holder 6 with a hammer 8 coacting with an anvil portion 10 of the press bed for flattening each slug w. The nut shaping die 3 is mounted in the die holder 6 and the other die 2 is fixed in the bed. The hammer 8 and die 3 are reversible and have inclined surfaces so as to be held securely by set screws and blocks. Each slug delivered from the shoot c is received by a jaw 24, Fig. 8, on a feed slide 23 and pushed under the flattening hammer 8, the slide being reciprocated by a lever 40 pivoted to the press frame at 41 and carrying a roller engaging a swinging slotted lever 42 actuated by a link 43 connected to the cross-head 7 at 45. The flattened slug is advanced under the die 3 by another jaw 25, Fig. 8, pivoted at 26 to the slide 23 and lifted over the preceding slug on its backward movement by means of a switch plate 28, the latter being pivoted at 29 and lifted out of the way by the pin 27 on the forward stroke of the member 25. In the shaping oi the blank to hexagonal &c. form x by the die 3 a ring of scrap y is forced over the die 2 against a plate 13 which thereby descends or is mechanically lowered, and the hole in the nut is punched at the same time by a punch 11. When the die holder rises the plate 13 is raised by a rod 14 and cam device 14<1> so as to strip the scrap y from the die 2, the scrap being then brushed aside by a brush 30, Fig. 8, pivoted at 31 and actuated by the feed slide 23 through the catch 35, lever 33 and link 32; the lever 33 is released from the catch 35 by a stop 36 and is returned to normal position by a spring 37. The punch 11 is mounted by its bead 15 in slots 16 in a screw 17 on the die head 6, and may be adjusted to come into operation at the same time as the shaping die or not until the shaping is completed or so that the punching is completed before the shaping begins, whereby the outward flow of metal which goes into the scrap ring y may be varied to alter the thickness of the finished nut blank. 'The nut ejector 18 rests loosely on the top of the nut and has yoke arms 19, Fig. 7, carrying set screws 21 adapted to engage fixed stops 22 as the die holder rises so as to strip the nut x off the punch 11 and out of the die 3, the nut falling on to a movable shoot 38 swung to and fro by a rod 39, Fig. 1, operated by the press head. The action of the cutting edges of the die 3 results in the crowning of the top of the nut round its edges. In the construction shown in Fig. 12 the ejector 18 is concave and is operated by rods 46 and cams on the mainshaft. Castellated nuts may be produced by providing the punch 11 with fins 11', as shown in Fig. 23, the ejector 18 having corresponding fins 18'. Any suitable form of scrap metal may be used such as metal slugs or punchings from plates, bars, nut blanks, &c or sections of bolt rods, crop ends of plates &c. The blanks are heated to a temperature of 1200‹-1500‹ F. so that the pressure of the shaping die depresses the soft metal adjacent the cutting edges of the die and the nut becomes smoothly crowned.