| 摘要 |
PROBLEM TO BE SOLVED: To provide a tunnel boring machine capable of detecting the slip of a gripper shoe, preventing the fall and damage of a timbering member, and avoiding the surface slip or collapse of natural ground. SOLUTION: In this tunnel boring machine, the abutting part 13 of a sensor 10 provided on the rear side surface of a gripper shoe 9 on the front side in the axial direction of the tunnel is brought into contact with a timbering member 6 to slide inside a cylindrical body 11 in the axial front direction of the tunnel by the action of a coil spring 12, so that the supporting shaft 14 is moved forward in accordance with the slide of the abutting part 13 to be brought into contact with a limit switch 15 for detecting the slip. The detection signal is input into a control devicer, which stops the extension of a thrust jack 5 to stop the slip of the gripper shoe 9. |
