| 摘要 |
PURPOSE:To excavate a rectangular form of tunnel by a method in which a cutter head having three arm cutters or equilateral triangular face plates is turned and the rotary center is biased and reversely turned with a given multiple speed. CONSTITUTION:A cylindrical rotator 6 having a horizontal through-hole 5 on a biased position is provided to the front of a shield machine 1, and a rotary shaft 9 is rotatably set in the hole 5, and a cutter head 11 having radially and projectionally set three arm cutters 10 at equal angle intervals is attached to the front end of the shaft 9. The first drive motor 13 is then attached to the rear of the rotator 6 and the second drive motor 15 to turn the rotator 6 with three times' speed to the opposite direction of the turning direction of the rotator 9 is provided to the shield machine 1 side. The cutter head 11 is turned to a given direction and the turning center is biased to turn it with three times' speed to the opposite direction. A triangular form of tunnel can thus be excavated. |
