Apparatus for detecting eccentricity of roll in rolling mill

Abstract

An apparatus for detecting a roll eccentricity in a rolling mill includes mark pulse generators each provided for upper and lower rolls from which an eccentricity is to be detected, the mark pulse generator generating one pulse per one rotation of the roll, sampling pulse generators each provided for the upper and lower rolls for generating n pulses per one rotation of the roll, and a rolling pressure detector for the rolls. After a mark pulse is generated, the rolling pressure signal outputted from the rolling pressure detector is first stored at the output timings of the sampling pulses. Next, a difference of the rolling pressure signals outputted from the rolling pressure detector is subjected to a Fourier transformation, the rolling pressure signals corresponding to those obtained after and before the relative phases of the upper and lower rolls are changed. The resultant values together with rotary angles and relative phases are used to output an eccentricity quantities independently for each roll.