TUNNEL EXCAVATOR

摘要

PROBLEM TO BE SOLVED: To facilitate tunnel excavation continuously in response to the change of a tunnel-excavation cross section quickly during tunnel excavation. SOLUTION: A corner cutter device 24 is installed to the outer circumferential section of an excavator body 11, in which a cutter head 13 is mounted on a front section in a freely driven and rotated manner and which can be forwarded by a shield jack 21. A corner cutter 32 is set up rotatably to the front section of a cylindrical case 25 while a driving motor 34 driving the corner cutter 32 is installed at that time, and the case 25 is supported movably along the circumferential direction of the outer circumferential section of the excavator body 11 by a hydraulic cylinder.