VARIABLE CROSS-SECTION SHIELD MACHINE

摘要

PROBLEM TO BE SOLVED: To provide a variable cross-section shield machine having high strength and capable of coping with excavation with large variation in cross-section by a simple structure. SOLUTION: This variable cross-section shield machine comprises main cutters 7 and 37 pivotally supported on the front part of the machine in the excavating direction eccentrically to a rotary drum 5 and width-enlarging cutters 8 and 38 having base end parts 11 and 39 pivotally supported near the peripheral edge parts of the main cutters 7 and 37, the other end parts 12 and 41 formed free, and installed movably to the radial outer side. COPYRIGHT: (C)2005,JPO&NCIPI