| 摘要 |
PURPOSE:To excavate the natural ground, discharge sediment to a pressure chamber with an earth removing device, and smoothly discharge the sediment by rotating a cutter head around a revolving shaft body, and reversely rotating it around a rotating shaft body at a speed higher than that for the revolving shaft body. CONSTITUTION:A revolving shaft body 6 is provided on a bulkhead 3 at the front section of a shield main body 1 rotatably around the central axis of the shield main body 1. A rotating shaft body 7 is arranged rotatably around the axis eccentric by a prescribed quantity from the revolving shaft body 6, and a cutter head 9 protruded from an arm-like cutter 8 is provided at its front section. The cutter head 9 is rotated around the revolving shaft body 6, and it is rotated around the rotating shaft body 7 in the reverse direction at a speed three times that for the revolving shaft body 6. The tip section of the cutter head 9 is rotated in a rectangular shape, and a tunnel having a rectangular cross section is excavated. The excavated sediment is moved into a pressure chamber 33, and it is fluidized and discharged to the pressure chamber 33 by an earth removing device 34. When the cutter head 9 is rotated, a scraping member 35 is rotated and moved at corner sections to scrape and remove sediment, and the sediment is smoothly discharged. |
