| 摘要 |
PROBLEM TO BE SOLVED: To provide a double tube system pipe excavation device, easily repairable and replaceable, in damage and abrasion of an excavation cutter and a bit. SOLUTION: In this double tube system pipe excavation device, an installation base 210 is rotatably or slidably installed on a cutter head 200 of the excavation cutter 20, and the bit 240 is installed on the installation base, and a stopper part 250 for positioning the installation base is arranged on the cutter head. When the excavation cutter excavates and rotates, the installation base rotates or slides by pressure received from sediments, and is positioned by the stopper part so that the outside end in the radial direction of the bit is positioned equal to an outside surface of a jacking pipe or on the outside of this surface, and when the excavation cutter reversely rotates, the installation base is reversely rotated or reversely slid, and the outside end in the radial direction of a roller bit is positioned inside an inner surface of the jacking pipe. COPYRIGHT: (C)2006,JPO&NCIPI |
