Patent ID: 8789890

Claim:
An abrasion detecting apparatus configured to detect abrasions of a plurality of components of a cutter head of a tunnel boring machine configured to excavate a ground using a cutter to bore a tunnel, the abrasion detecting apparatus comprising; abrasion detection probes respectively including at front end portions thereof abrasion detecting portions which abrade away by contact with the ground to be excavated, the abrasion detecting portions being located rearward of a front end of the cutter by a first distance and located forward or rearward of front ends of the plurality of components, whose abrasions need to be detected, of the cutter head by a second distance, the abrasion detecting portions projecting forward from a front surface of a cutter head frame by a third distance; and a detecting device configured to detect an abrasion of the abrasion detecting portion, wherein: attachment external screw portions are respectively formed at rear end portions of the abrasion detection probes, and sealing portions are respectively formed forward of the external screw portions, the sealing portions respectively including O-ring grooves, and O-rings being respectively provided at the O-ring grooves; and the abrasion detection proves are detachably attached onto a slit adjusting plate of the cutter head so as to be respectively provided on rotational trajectories of the plurality of components of the cutter head, the abrasion detection probes respectively detecting abrasion losses of the plurality of components, the slit adjusting plate being configured to adjust a size of an opening of a sand intake port provided between the cutter head frame and the slit adjusting plate.