Use the ring bit excavation direction adjustment easy excavation manner and the ring bit

摘要

PURPOSE:To improve workability with inexpensive construction by setting the fitting angle of bits on one periphery of a ring bit excavating the hard ground outward, straightly excavating the ground at the speed of the peripheral speed or above, and correcting the direction with the oscillating rotation in the specific angle range. CONSTITUTION:Bits 2 of a ring bit 1 are divided into four, only a bit train A on one periphery is fitted outward, a bit train B on the opposite side is fitted inward, and other bits are fitted normally straightly. The ring bit 1 is rotated 360 deg. or above for normal rotation, and a base rock 3 is straightly excavated. When a direction change is required, the outward bit train A is located in the correction direction, the oscillating rotation motion is performed at the angle + or -45 deg. to obliquely excavate. After the direction change, it is again rotated 360 deg. or above to be returned to straight excavation. The excavating direction is quickly and easily corrected during excavation, and workability can be sharply improved.