DEVICE FOR MONITORING WEAR OF MATERIAL UNWOUND FROM ROLL

摘要

PURPOSE: To accurately detect an amount of strip remaining on a roll being worn by detecting an electric impedance generated in a roll and a roll shaft assembly so that a signal can be relayed when this detection value corresponds to a preset value. CONSTITUTION: A detecting means 7 which is actuated at a supply part 1 for detecting a natural impedance to a roll 2 and the assembly of a roll shaft 3 is provided. When the impedance detected by the detecting means 7 is equal to a reference value, an output signal is relayed to a control means 14 by a measuring and comparing means 22 and the replacement of the empty roll 2 with a filled roll is started in accordance with the output signal.