PROTRUSION DETECTION DEVICE AND PROTRUSION DETECTION METHOD

摘要

A projection detecting apparatus according to the present invention is that for detecting a projection on a surface of a running metal object, and includes a transmission antenna for radiating electromagnetic waves; a reception antenna for receiving reflected electromagnetic waves; and a transmission and reception signal processing section for processing a transmission signal and a reception signal. The transmission antenna and the reception antenna have unidirectionality and the transmission antenna and the reception antenna are installed in such a way that the reception antenna does not catch electromagnetic waves which have been radiated by the transmission antenna and reflected on the surface of the metal object and the reception antenna catches electromagnetic waves alone which have been radiated by the transmission antenna and reflected on the projection.