| 摘要 |
PROBLEM TO BE SOLVED: To prevent a lowering of excavation efficiency in a tunnel excavator by easily replacing a cutter bit even if it is worn away and improve the safety and work efficiency. SOLUTION: A cutter head 12 is rotatably mounted to the front of a skin plate and a mount seat 32 is mounted to cutter spokes 13 radially fixed to the front of the cutter head 12 through a supporting axis 31 so as to be swingable forward and rearward in the excavation direction. A cutter bit 14 is mounted to the seat 32 through a bolt 33 so as to be turned between a projecting position and a replacing position. On the other hand, a fixing plate 35 holding the bit 14 at its projecting position is secured to the spokes 13 through a bolt 34 to fix the bit 14 at the projecting position. |
