| 摘要 |
The present invention relates to a cutting tool for cutting the edge of a hole. The cutting tool comprises: a connection shaft (10) formed of a vertical structure and connected to a shaft rotating device (Not shown) rotated at high speeds; a body part (20) arranged at the bottom of the connection shaft (10); a cutting part (30) arranged at the bottom of the body part (20) and formed of a pair of cutting blades (31) and a pair of cutting passages (32); a hole center maintaining part (40) arranged at the bottom of the cutting part (30); a hole entrance guide part (50) arranged at the bottom of the hole center maintaining part (40); and a pair of chip discharging passages (60) arranged close to the pair of cutting blades (31) of the cutting part (30) to discharge upward cut chips. Especially, the outer diameter of the hole entrance guide part right under the hole center maintaining part is drastically narrowed downward from the top. Thus, the present invention can drastically reduce work time and the number of processes to improve workability by fundamentally processing the edge of a hole with a single cutting tool and can relieve the risk of safety accidents by removing an additional grinding process. Also, the present invention enables the cutting tool to be smoothly inserted into the hole by the inclined surface, thereby improving the workability. |
