| 摘要 |
PROBLEM TO BE SOLVED: To provide a support structure of various apparatuses in a tunnel boring machine easy in replacing cutters and the other apparatus installed on a cutter head in the tunnel boring machine, capable of reducing the size of the whole device, and enabling effective use of a narrow work space. SOLUTION: A bit support structure 120 externally exposes and supports a tip part of a relay bit 111 to and by a tunnel boring machine body, and rotatably supports a circular arc surface part 121a of a bit support member 121 on a recessed spherical surface-shaped sliding surface 122a of a housing 122 in a seal state. The relay bit 111 is slidingly sealed, and inserted into and supported by a bit inserting hole 121b of the bit support member 121, a tip part of the relay bit 111 is installed by penetrating outside from a bit advancing- retreating hole 122b of the housing 122, and the axis of the bit inserting hole 121b is arranged so as to be orthogonal to a rotary shaft 124 of the bit support member 121. When the tip part of the relay bit 111 projecting outside from the bit advancing-retreating hole 122b is pulled in the bit inserting hole 121b, the bit support member 121 rotates together with the relay bit 111. |
