Patent GB-342599-A (GB)
Title: Improvements in or relating to roller machines for the treatment of metal sheets
IPC: B21D1/02
Filed: 1930-04-02
Abstract: 342,599. Bending and straightening. BUDD MANUFACTURING CO., E. G., 25th Street, Philadelphia, U.S.A.-(Assignees of Eksergian, C. L. ; 12141, Charlevoix Avenue, Detroit, Michigan, U.S.A.) April 2, 1930, No. 10426. Convention date, April 3, 1929. [Class 83 (iv).] A machine for working metal sheets by bending and roll straightening apparatus of the type described in Specification 252,738, [Class 83 (iv), Metals, Working], has the bending element moved transversely to the path of the sheet fed to the machine by the displacement of one of the feed rollers due to the contact of the sheet therewith. The machine comprises a guide plate 21 at the feeding-in end of the machine, guide rolls 20, a movable bending element or working roll 17 to form a working bend in the sheet, twc pairs of feed rolls 16, and a number of straightening roll: 12. The rolls are driven by a motor M and transmission gear. ing T. Working roll 17 is raised and lowered by links 27 and arms 26 on a shaft 24 rocked by an arm 28 and link 29 connected to a crosshead 34 actuated by a piston rod 33 of a pneumatic cylinder 31. The piston is formed of two parts 32, 32<1>, the latter formed with a screwed sleeve 36 screwing on the threaded piston rod 33 and adjusted by gears 37, 38, sprocket 40, chain 42 and hand wheel 41 for varying the stroke of the piston. Air is admitted to and exhausted from the cylinder 31 by a relay valve R, the main valve of which is operated by air admitted by a small valve operated by an electromagnet 52 in a battery circuit, Fig. 12. With the switches 57, 58 moved to the dotted line positions the battery electromagnet circuit is still incomplete at two points, the gap between rolls 20 and feed rolls 16 and the automatic control switch T. The gap is bridged by the sheet fed, and the pivoted arm 61, Fig. 5, of the automatic switch T is actuated by the upward movement of the feed roll 16 when the sheet enters between the feed rolls, whereby the circuit is completed and the pneumatic cylinder operated to raise the working roll 17 into the position shown in Fig. 5. This movement is cushioned by air trapped in the cylinder which is provided with a number of spirally arranged ports 43 some of which may be plugged to vary the cushioning effect. The return movement is cushioned by a cylinder 46 and piston 47 connected by a rod 481 and arm 49 to piston rod 33 so as to move therewith, the piston 47 loosely fitting the cylinder 46 and restricting the exhaust of air from the exhaust port 44 only at the end of the return stroke. A safety switch W is provided to open both the battery circuit and the motor circuit 53, 54 if a sheet commences to wrap round the first feed roll 16, the end of the sheet in this event engaging a stop 66 and actuating the pivoted switch arm 65. The feed rolls are supported on large rolls 70<1> in a pair of cages 70 mounted on knife edges 72 and pressure is applied above the feed rolls by rolls 73<1> in cages 73 bridged by a bar 74 with socket 75 engaged by a pin 79 forced down by a heavy spring 82 engaging a collared sleeve 83 screwing on the pin 79. When no sheet is passing through the machine the sleeve collar 83 contacts with the fixed pressure bridge 77 thus relieving the rolls 16 of the spring pressure. The latter is adjustable by a number of nuts 85 provided on their rims with worm wheels engaged by worms on a shaft 88 operable by a hand wheel 89, the nuts 85 working on screw studs 84 fixed in the bridge 77 and engaging a pressure head 78 bearing on the end of the spring 82.