| 摘要 |
PROBLEM TO BE SOLVED: To timber a drilling plane by spraying hardening material thereto at an early stage. SOLUTION: A spray nozzle 2 for hardening material is opened in the outer periphery of a cutter head 10 and a first supply pipe to supply hardening material to the spray nozzle 2 is extended from the rotation center of the cutter head 10 through the entrance of the nozzle 2 ranging into the cutter head 10 inwardly to the cutter head 10. It is connected to a second supply pipe 3C via a rotary joint 3B arranged to be coaxial with the cutter head 10. The second supply pipe 3C is connected to a supply source for the hardening material set up in an existing tunnel via a front body 20 and a rear body 40. By spraying the hardening material from the spray nozzle 2 during drilling, the hardening material can be sprayed to the inner periphery wall of a drilled pit at an early stage. |
