| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a boring machine for preventing the spread of crushed pieces and dust during withdrawing work for underground pipe. <P>SOLUTION: A boring machine 1 has a cutter head 2 at the front end in the boring direction. The cutter head 2 has a cylindrical supporting part 20, and a cutter bit mounted on the supporting part 20 for crushing an underground pipe 8 such as an asbestos pipe while drilling mud. A cylindrical extension hood 3 is joined to the supporting part 20 of the cutter head 2, and extends to the further front end side than the front end of the cutter head 2 while covering the cutter head 2 in its radially outward direction. A driving motor 50 drives the cutter head 2 and the extension hood 3 to be integrally rotated. When the cutter head 2 crushes the underground pipe 8, the scattering of crushed pieces 81 of the underground pipe 8 and dust into soil can be prevented because an area around the underground pipe 8 is encircled by the extension hood 3. <P>COPYRIGHT: (C)2013,JPO&INPIT |
