摘要 |
An annular hole cutter has a radially inner cutting tooth portion and a radially outer cutting tooth portion. Each of the inner and outer cutting tooth portions is formed with a flute for ejecting cut chips on the outer periphery of the cutter, and a cutting edge for radially outwardly pushing the cut chips. Therefore, the cut chips are smoothly ejected through the flute, and thus an annular hole is precisely cut at high speed. |