Patent ID: 9115979
Filing Date: 2015-08-25
Classification: G01B

Abstract:
1. A web thickness measuring equipment comprising: a roller that is rotatable and configured to wind a web on the roller and move the web in a rotating direction of the roller; a light source that irradiates light to at least one of an outer circumferential surface of the roller and a target external surface of the web; a light amount sensor facing the light source, the roller positioned between the light amount sensor and the light source, the light amount sensor configured to detect in real time light amounts of the outer circumferential surface of the roller and the target external surface of the web according to a light amount distribution change of the light irradiated from the light source and having passed through the outer circumferential surface of the roller and the target external surface of the web, respectively; a transfer frame on which the light source and the light amount sensor are installed, wherein the transfer frame moves in a lengthwise direction of the roller with respect to the outer circumferential surface of the roller or the target external surface of the web; a magnetic member arranged between the transfer frame and the web and being spaced apart from the roller; a Hall sensor on the transfer frame configure to detect in real time a magnitude of a magnetic field between a target internal surface of the web and the magnetic member; and a processor receiving information from the light amount sensor and the Hall sensor, wherein the processor is configured to obtain a thickness of the web by generating profile data of the outer circumferential surface of the roller using a light amount detection signal of the outer circumferential surface of the roller, generating displacement amount data of the target external surface of the web moving in real time using a light amount detection signal of the target external surface of the web, generating displacement amount data of the target internal surface of the web using a magnetic field detection signal of the target internal surface of the web, and comparing the displacement amount data of the target external surface of the web with the displacement amount data of the target internal surface of the web.