AUTOMATIC LINE FOR CUTTING PLATES FOR MAGNETIC CIRCUITS OF TRANSFORMERS FROM STEEL BAND

1,222,975. Shearing. G. I. PSHENICHNY, Y. Z. CHECHELJUK, M. A. AFANASIEV, and N. N. KHMARA. 22 Feb., 1968, No. 3240/68. Heading B3W. An automatic line for cutting steel strip into plates for transformers comprises a first rotatably mounted shear 10 for cutting plates with two acute corners, a feed device 12 for transferring blanks but by shear 10 to a second shear 11 for trimming off one of the acute corners which has an upper and a lower blade, 27, 26 each of which is in two sections spaced to allow an electromagnetic member 28 of the feed device to pass through the shear to receive the plates cut by the shear 10 and carry the plates first to the shear 11 and then to a device (13) (Fig. 5, not shown) for removing finished plates from the line. In operation, strip is first fed by hand from an unwinding device (1) (Fig. 1, not shown) through a tensioning device 5 to a feed mechanism (6) comprising two gripper carriages (7) (Figs. 2 and 3) reciprocating in alternate feed and return strokes. The drive (3) of the device (1) and the hydraulically-actuated rack and pinion drive (8) of the feed mechanism (6) are then switched on. One carriage (7) feeds the strip to the shear 10 which is disposed at 45 degrees to the feed direction of the strip. When the carriage reaches an adjustable stop (9) adjacent the shear 10 the drive (8) is stopped and the tensioning device (5) and the shear 10 are actuated. Whilst the other carriage executes a feed stroke the shear 10 is rotated through 90 degrees so that the next cut will produce a plate of regular trapezium shape. After the cut the feed device 12 is moved by hydraulicallyactuated rack and pinion drive 33, until it abuts a retractable stop 32, to feed the plate to the shear 11 which trims off the leading acute corner. The stop 32 is then retracted and the feed device 12 carries the trimmed plate to the device 13 which comprises two groups of electromagnetics mounted on a carriage reciprocable transversely of the automatic shearing line to deposit finished alternately in bins disposed one on either side of the line. A switch (4) in a pit adjacent the unwinding device (1) stops the drive of the device when a reserve of strip has formed in the pit. The spacing between side guide rollers 24 for the strip is adjustable.