JPS5756730A - Method and device for measuring distribution of tensile force in widthwise direction to strip - Google Patents

Abstract

PURPOSE:To obtain desired frequency resolution by vibrating a tensed strip, by taking a measurement by adding periods at the beginning of the vibrations, and by calculating a mean vibration frequency by the addtion period. CONSTITUTION:A strip 1 is tensed by a tension roll 3 at the exit of a rolling mill and vibrated by exciters 4a, 4b and 4c, and the vibrations are detected by vibration detectors 5a, 5b and 5c, A displacement signal Va is passed through a band filter 6 and a notch filter 7 to input an output (e) to a comparator 8. The comparator 8 generates and supplies a rectangular wave pulse (s) to a vibration period adding circuit 9, which applies pulses P1 and P2 to an FF11, outputting a rectangular wave signal (m). This output (m) is inputted to the AND gate 13 of a vibration period measuring circuit 12 together with a reference pulse C to be counted by a counter 15. The count value tSIGMA of the counter 15 is inputted to a squaring device 17 through a reverse counter 16. Its squared value f<2>ma is supplied to a display device 20 through a register 18 and a D/A converter 19 to display the tension distribution of the strip 1.