| 摘要 |
PROBLEM TO BE SOLVED: To suppress an increase in manufacturing cost by a simple structure by excavating a natural ground while reducing the looseness of the natural ground around a cutter. SOLUTION: In this shield machine 1, extensible jacks 10 of proper number are fixed to a cutter ring 7 fitted to a shield machine body 3, and the tips of the extensible jacks 10 are fixed to a disk-shaped cutter 4 to form a cutter mechanism 5. The cutter 4 is divided into two parts and forms semi-disk shaped first cutter 4a and second cutter 4b, and moved forward and backward in the advancing direction of the shield machine 1 by the extension and retraction of the extensible jacks 10. The shield machine also comprises a slide hood 13a covering an opening part 14 formed between the projected cutter 4 and a skin plate 2 when the first cutter 4a or the second cutter 4b disposed at the upper part is projected. COPYRIGHT: (C)2006,JPO&NCIPI |
