| 摘要 |
PROBLEM TO BE SOLVED: To provide a shield machine 1 which can always stabilize a working face by adequately maintaining the pressure in a chamber 14 during excavation. SOLUTION: The shield machine is formed of a shield frame 11, a cutter face 12 for excavating the natural ground G via its tip, the chamber 14 formed on a rear surface of the cutter face, for charging excavated earth therein, an earth removing pipe 15 for discharging the excavated earth from inside the chamber 14, and a chamber internal pressure maintaining device 17 for maintaining the pressure in the chamber 14. The chamber internal pressure maintaining device 17 is formed of an inflatable film 171 arranged in the earth removing pipe 15, a pressure source 173 for applying fluid pressure for inflating or deflating the inflatable film 171, and a pressure sensor 174 for always detecting the pressure in the chamber 14. Then the pressure applied to the inflatable film 171 by the pressure source 173 is controlled based on a deviation between a preset reference pressure value and a pressure value detected by the pressure sensor 174. COPYRIGHT: (C)2008,JPO&INPIT |
