| 摘要 |
A rotary cutter is provided with a spiral plane bit which comprises a mounting plate extending spirally in the axial direction with a constant width, the mounting plate being made in such a manner that it is spirally cut out of a hollow cylinder with the inner radius of the mounting plate and a bit edge member extending also spirally along one lateral margin of the mounting plate and being fastened thereto, wherein there are provided a plurality of fastening holes arranged in the mounting plate in the longitudinal direction thereof, through which fastening elements extend radially into a plurality of threaded holes so as to fasten the mounting plate together with the said bit edge member on a rotary shank. This spiral plane bit is advantageously employed particularly for cutting wood material, because the spiral plane bit makes point contact with a workpiece of wood material and the contact point is displaced over the whole length of the spiral plane bit during cutting operation, resulting in smooth and uniform cutting with a less noise. The spiral bit edge is fastened to the mounting plate angularly displaceable so as to adjust the fastening position thereof. |
