| 摘要 |
PROBLEM TO BE SOLVED: To provide an auger head capable of efficiently excavating any kind of soil.SOLUTION: Each of two or three blade parts of an auger head has a plurality of holders for holding a bit. Among the plurality of holders provided on each of the two or three blade parts, the holder placed on the innermost side is defined as a center part holder, the holder placed on the outermost side is defined as an outermost periphery holder, and the holders other than the center part holder and the outermost periphery holder are defined as middle stage holders. The center part holder of each blade part is arranged on a first circle whose center is a rotary axis. The outermost periphery holder of each blade part is arranged on a second circle whose center is the rotary axis. The middle stage holder of each blade part is arranged on a concentric circle of a different diameter whose center is the rotary axis, which is the circle different from the first circle and the second circle. On the inner side of the first circle, at least one of a centroid and an excavation center is placed. |
