| 摘要 |
PROBLEM TO BE SOLVED: To increase effects for cooling and dust removing with a simple mechanical structure. SOLUTION: For a drilling method, a cup-like core bit 17 is used and a surface G is drilled while a tip part is pushed on the surface G to be drilled with being rotated. The core bit 17 is rotatively supported on a rotary shaft 16 of a drilling machine 2. A dust collection passage communicating with the inside of the core bit 17 is provided in the rotary shaft 16. A swivel joint 18 is provided on an outer periphery to an upper side of the rotary shaft 16, and a dust collector 3 is connected to the dust collection passage via the swivel joint 18. Dust generated following rotation of the core bit 17 is sucked inside the core bit 17 by vacuum suction with the dust collector 3 and collected inside the dust collector 3 via the dust collection passage, the swivel joint 18 and a hose 8.
|
