| 摘要 |
PROBLEM TO BE SOLVED: To conduct outbreak works corresponding to a ground status by projecting and retreating a cutter bit to and from the front of a cutter head by a hydraulic cylinder and installing a working-pressure detecting means and a stroke detecting means of the hydraulic cylinder. SOLUTION: A copy cutter 10 is mounted at the front end of a cutter spoke for a rotary cutter head. A copy-cutter bit 12 is fixed at the end of a piston rod for a hydraulic cylinder 11 at the front end section of the cutter spoke. In a hydraulic circuit for the hydraulic cylinder, a high-pressure side circuit H and a lower-pressure side circuit L are arranged in parallel, and can be changed over. A pressure sensor 19 and a stroke sensor 20 are fitted to both circuits, and the characteristics of a ground are decided. When the characteristics of the ground are not investigated and an outbreak is conducted, the hydraulic circuit is changed over to the high-pressure side circuit H, and the outbreak and excavation are performed simultaneously. When the characteristics are investigated, the revolution of the cutter head is stopped while hydraulic pressure is changed over to the low-pressure side circuit L, a pressure change and a hydraulic flow change are detected, and the pressure, hardness, etc. of a ground are measured. |
