| 摘要 |
PROBLEM TO BE SOLVED: To provide a multi-tube diverging shield machine which includes a rectangular excavator and circular excavators in a manner being divergeable therefrom, and can excavate an envelope cross-sectional area of each excavator. SOLUTION: The multi-tube diverging shield machine is comprised of the rectangular excavator 2 having a rocking cutter 9, the circular excavators 3 being adjacently arranged to the rectangular excavator 2 and each having a main cutter disk 4, and an outer shell member 5 housing the circular excavators 3 therein in a manner being divergeable therefrom, and having the rectangular excavator 2 connected thereto in a manner being divergeable therefrom. The rocking cutter 9 has a plurality of cutter spokes 11 radially extending from the vicinity of a rocking center C. Further, over cutters 11a which are retractable in an outward direction are arranged in the vicinity of the respective tips of the cutter spokes 11, and by advancing and withdrawing the over cutters 11a in synchronization with rocking of the crocking cutter 9, the tips of the over cutters 11a draw a cross-sectional outer shape of the rectangular excavator 2 or a moving orbit proximate to the same. |
