| 摘要 |
PROBLEM TO BE SOLVED: To advance a boring machine by cutting gravel without affecting the surrounding ground when the boring machine hits the gravel during an advance. SOLUTION: The boring machine for boring a tunnel of rectangular cross section is provided with a plurality of gears rotating around perpendicular axes, inside an outer enclosure of the boring machine. A blade belt with blades arranged in belt shape is stretched over the gears. The blade belt is constituted to travel along a gear group in the exposed state of the front face of the boring machine. COPYRIGHT: (C)2011,JPO&INPIT |
