| 摘要 |
PROBLEM TO BE SOLVED: To excavate a noncircular excavation cross section, by providing circular and noncircular loci in the same center, while reducing rotational run-out and vibration of a driving system and reducing the driving system and design cost. SOLUTION: This rotating mechanism has a central shaft 31 rotatably arranged around the predetermined fixed enter line O, a main blade member 211 extendedly arrange in the radial outward direction of the central shaft, a rotary shaft 33 rotatably arranged to the main blade member around the moving center line P parallel to the fixed center line, a sub-blade member 221 having the contour defined by a semicircular part of a semicircular shape and respective circular arc parts continuing by respectively forming the same circular arc from respective end parts of the semicircular part and fixed to the rotary shaft by aligning the rotational center G of placing a predetermined eccentric quantity (r) with the moving center line in the vertical direction to a diameter on the semicircular part side from the center of the diameter of the semicircular part in the contour, a driving part rotatingly driving the central shaft, and a rotation transmitting mechanism 34 rotating the sub-blade member twice in the same direction to one rotation of the main blade member 1. COPYRIGHT: (C)2007,JPO&INPIT |
