Patent GB-237637-A (GB)
Title: Improvements in and relating to presses for drawing metal articles
IPC: B21D24/00
Filed: 1924-04-01
Abstract: 237,637. Nobel Industries, Ltd., (Du Pont de Nemours & Co., E. 1.). April 1, 1924. Cupping. - In a cupping-press for drawing shells of comparatively great length from the cup to the fully drawn shell in a continuous automatic operation without annealing between successive drawings, the cups are forced completely through each die and then retracted through the same die for transmission to the succeeding die except in the case of the final or delivery die. The apparatus comprises two press units fed through pipes 5, Fig. 1, from a common hopper H. The cups in each unit are received on a reciprocating table whereby they are advanced stepby-step over a row of dies 2 of decreasing diameter to receive successive drawings from plungers 3 operated by crank gear from the main driving shaft 60, the finished shells being delivered through the last die 18, Fig. 4, and the metal removed being ejected down the shoot 19 by an air blast through the pipe 21. Ejectors 6, Fig. 4, are raised by cam mechanism 10 against the action of springs 7 to re-deliver the shells from each die to the reciprocating table ready for transmission to the next die. Fixed stripper plates 14 act at the same time to force the shells from the plungers, and the scrap from the final plunger of the series. The reciprocating slide is made up of two sections rigidly connected, one section being adapted to co-operate with the actuating cam 23, Fig. 1, on the shaft 24, while the other carries the gripping and releasing mechanism comprising pairs of gripping slides 25, Fig. 3, adapted to grip and release the cups automatically. Sliding cam plates 27, Fig. 5 are moved by other cams on the shaft 24 in timed relation with the part 22b of the main slide so that rollers 43 on the gripping slides are actuated to retract these slides at the right time against the action of springs 26. The feeding mechanism for supplying the tubes 5 comprises a rotating disc 54, Fig. 8, driven by belt and spur gear from the main driving shaft. This disc carries a series of spring-mounted hooks 73 which project into a channel running all round the periphery of the hopper. Cups fall by gravity into the lower part of the channel and such as are positioned with their open ends facing rearwardly are caught on and carried forward by the hooks. On the journey the cups that face in the wrong direction are removed from the channel by a spring 128, those on the hooks being carried right round to the stop 89 which trips the hooks so as to remove them from the channel, leaving the cups in the entrance to the pipe 5. A fixed cam 92 assists in keeping the hooks in position during transit. Provision is made for the automatic interruption of the feed when the column of superposed cups in the pipe reaches a certain length, and for the resumption of the feed when the column is reduced again. A jointed and pivoted sliding member 108 is normally forced rearwardly by a spring 112 so that the pin 104 at the rear end is clear radially of the cams 85 on the hooks. When this sliding member is moved forward, the pin 104 is moved also radially inwards so that it trips the hooks at an interrupted part of the cam 92 and allows the cups to fall back into the body of the hopper. The slide is actuated by the contact of the hooks with the top of the column of cups and resultant tripping at a, point where the fixed cam surface recedes to allow the hook carriers to swing. The tripped carriers then assume a position in which they actuate the pin 125 to move the slide. A detent 117 prevents reverse movement. Eventually the column of cups becomes lessened sufficiently for the tripping to be retarded so much that the carriers have not time to get out of the way of the lever 124. The actuation of this lever raises the detent and the spring 112 then restores the parts to resume feeding.