Patent GB-500558-A (GB)
Title: Improvements in or relating to redraw presses
IPC: B21D24/00
Filed: 1937-08-10
Abstract: 500,558. Cupping. WATERBURY FARREL FOUNDRY & MACHINE CO. Aug. 10, 1937, No. 22004. Convention date, April 10. [Class 83 (iv)] Metal cup blanks arc further cupped to size, e.g. to make cans. in a press provided with a number of co-operating punches and dies which are first successively stepped down to lower levels to facilitate horizontal transfer from one cupping station to the next, while the succeeding dies are on one level. Fig. 6 shows the first cupping stations each one at a lower level than the others to receive the work when pressed through the previous die, and the end four stations are on the level. Fig. 5 shows the cups at successive stages, the first three, 11, 12, 13, being drawn with a short punch stroke, the next two 14 and 15, with a longer punch stroke, and the remaining four, 16-19, showing the formation of n shoulder 20 which is eventually cut off at 19, while at 17 the bottom angle is squared up and at is the bottom 21 is pressed in and corrugated. In operation a cup blank 10 drops down the shoot 203 and is pushed by 206 under the first punch 77 which draws it through the die 80 where the second horizontally-moving pusher 207 moves it beneath the second punch 78 which forces it through the second die 81 and similarly in sequence it is pushed through to the fifth die 87 to lie in front of the guide plate 277. Gauging stop plates 230, Fig. 13, position the cup at end of pushing- at, each stage while work holder sleeves 165 enter the cup in advance of the next punch and steady it during the pushing. If a damaged can sticks in the machine the corresponding pusher, e.g. 210, will slip over its connection with the slide 211, Fig. 11 (not shown), and on its return stroke will engage one of the trip fingers 312, Figs. 2 and 15 (not shown), and rotate a vertical shaft 305 so retracting detent 295 to allow a spring-pressed rod 287, Fig. 4 (not shown), to move as indicated in dotted lines to uncouple a clutch 26 through lever 188 and arm 193, Fig. 8 (not shown), and apply a brake 198, Fig. 4 (not shown). The can is stripped from each punch by spring-pressed ring segments and assisted by compressed air. After the fifth draw the shift bar 238 and rod 243 causes the double arm fingers to engage the can and move it along the bolster to below the sixth punch 85 where the sleeve holder enters it and the punch forces it through the die 88. When the punch 85 rises, a knock out 143 pushes the can up against the upper ring 140 and the double arm fingers 237, Fig. 9 (not shown), move it beneath the next punch 89 which redraws it and so on. The punch 91 and die 94 cuts off the scrap rim 20. The can passes through the die 94 and drops into the delivery shoot 95, while the scrap rim 20 is stripped off the punch and is blown into a scrap shoot. Dirt, chips, &c. are collected on raised pads 321, Figs. 19 and 20 (not shown), separated by grooves through which lubricant carries the chips away through openings 323, Figs. 19 and 20 (not shown), in the base of the die blocks. The die blocks have plates 125, Fig. 1 (not shown), which are removable to allow access to the space below the preceding die to remove a jammed can therefrom. The dies may be removed when holding plates 119, Fig. 1 (not shown) are removed by handle 121, Figs. 1 and 19, (not shown), side guide plates &c., and locating stops 230 guide the cans. The guide plate 277 moves rearwardly to avoid interference with the can as it is being ejected. The pushers are coupled to their drive 211 through a safety friction release clamp.