Single sheet classifier

摘要

900,606. Rolling-mill plant. BLAW-KNOX CO. Dec. 5, 1960 [Dec. 22, 1959], No. 41738/60. Class 83 (4). [Also in Groups XIX, XXXVI and XL (b)] In apparatus for sorting sheets in accordance with a characteristic measured before the sheets are sheared from a moving strip, a computer determines in which sheet said characteristic will occur and operates a deflector when the leading edge of the sheet is detected approaching the deflector. Steel strip from a roll C passes a pin-hole detector 11 to a shear 14, while a tachometer 24 produces pulses indicative of its travel. These pulses together with pulses produced by a tachometer 25 are used in conjunction with counts preset on units 45, 46, 47 in accordance with the distance between detector 11 and shear 14, detector 27 and detector 28 respectively to determine the number of complete sheets between detectors 11 and 27, the result being stored in register 39, and the distance of the next potential cut from the detector 11, the result being stored in register 37. When a pin-hole passes detector 11, a pulse is entered in a memory register 40 and is stepped through the register by pulses from tachometer 25 delayed in delay counter 38 to an extent determined by register 37. When the pulse has been stepped on a number of times equal to the number stored in the register 40, the next sheet to arrive at detector 27 will contain a pinhole, and the output from register 40 opens a gate between detectors 27 and 28 so that when the pin-holed sheet arrives at detector 27 the output thereof prepares detector 28 for the sheet. Passage of the sheet past detector 28 causes a pulse to be entered in register 41 which is shifted through the register by pulses from tachometer 30 corresponding to the passage of the sheet along conveyer 15. The pulse leaves register 41 when the pin-holed sheet is about to reach a detector 31 and gates the output of detector 31 to operate the solenoid of the deflector 16. The deflectors 27, 28, 31 are sensitive to the leading edge of the sheets and may be photo-electric or, provided the strip is ferrous, magnetic.