| 摘要 |
PURPOSE:To enhance the working efficiency in the excavation works by adjusting the protruding amount of a cutter bit using an adjusting means such as a hydraulic cylinder which can be locked mechanically. CONSTITUTION:The body 1 of an excavating machine is advanced by a plurality of shield jacks, and a cutter head 2 is revolved by a cutter driving motor 8, and the natural ground is excavated by a preceding cutter bit 4 and a protrusive cutter bit 5A. The cutter bit 5A is projected from the front face of a supporter 3 with elongation of a hydraulic cylinder 20 which can be mechanically locked in any position. When excavation of a certain distance is completed, the excavating force is restored by elongating the cylinder 20 and making the projecting amount of the bit 5A the same as prior to wear. Even though the bit 5A has worn again after this projection, the excavating force can be held constant by projecting the bit 5A however many times as applicable. |
