CUTTER DISK FOR SHIELD MACHINE

摘要

PROBLEM TO BE SOLVED: To provide a cutter disc for a shield machine capable of digging a lining member lining an inner face of a tunnel without using a large-scale auxiliary construction method, shortening a construction term, suppressing cost, and prolonging service life of a cutter bit. SOLUTION: A plurality of first cutter bits 17 for digging earth and sand and a plurality of second cutter bits 18 capable of digging a lining member lining an inner face of a tunnel are provided in each of a plurality of cutter spokes 12. A plurality of second cutter bits 18 can be switched to a retraction position where it is retracted more backward than the first cuter bit 17 and an advance position where it advances more forward than the first cutter bit 17, and the lining member can be digged by rotating a cutter disc 2 while a plurality of second cutter bits 18 are switched to the advance position.