| 摘要 |
PURPOSE:To enable it to bore the hard ground by installing a slide cutter unit, provided with a small diametral cutter head and its rotation driver and a traversing driver, in front of a machine body at top and bottom of each cutter head adjacent part of a multiple shield tunneling machine. CONSTITUTION:A shield jack 19 is extended and the rear end is made contact with a segment 20, then a shield machine body 6 is advanced forward, while each rotation of rotary drivers 12, 13, 14 is transmitted to those of preceding large diametral cutter head 9 and middle diametral cutter heads 10, 11, thereby digging earth and sand ahead. Next, the earth and sand digged by these large and middle diametral cutter heads 9-11 is discharged to the inside of a chamber A from cutter slits 15, 17. Then, the earth and sand in front of the part of a skin plate 21 at top and bottom of adjacent parts of these cutter heads 9, 10, 11 is digged by small diametral cutter heads 25 at four spots. With this constitution, a section oval tunnel can be smoothly digged. |
