| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for exchanging cutter bits of a shield machine, which can safely exchange a wide range of cutter bits with efficiency. SOLUTION: A shield main body 1 of the shield machine includes a cutter withdrawing mechanism 11 for withdrawing a cutter head 4 having cutter spokes 7A, 7B into a pressure chamber 2 along a shield axial center O. A pressure bulkhead 3 in the shield main body has an operation partitioning body 20 which houses therein the expandable spoke 7B, and allows therein exchange of the cutter bits 8. Further, the operation partitioning body 20 has a front aperture 23 formed in front thereof, and front shutters 26 arranged therein. The front aperture 23 allows insertion of the expandable spoke 7B thereinto. The front shutters 26 can open/close the front aperture 23 before or after housing of the expandable spoke 7B. Further, the front shutters 26 are each provided with a front gate 31 of an arched cross section, which is rotatable about an axial center in a radial direction. |
