| 摘要 |
PURPOSE:To enhance the efficiency of drilling work by installing a jet nozzle injecting in the longitudinal direction in a drilling machine in such a manner that it can be freely put in a turning movement, and placing the drilling machine on both side rails inside an excavated tunnel, and drilling a radial small bore hole at a desired position. CONSTITUTION:A gate-shaped frame 14 is placed on both side rails 9a, 9b laid rearwardly of a tunnel excavator in such a manner that it is moveable by trucks 15a, 15b. An arm 21 for supporting a jet nozzle 26 provided with a main nozzle 26a injecting in the axial direction and a sub-nozzle 26b is mounted to the beam portion 16 of the frame 14 in such a manner that it can be freely put in a turning movement via an arm 19. The connecting point between the arms 19, 21 agress with the center of a tunnel 7. When trucks pass onto a rail 9c, the arm 19 can retreat in the position of a chain line. The term of drilling work is thereby shortened. |
