| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve the balance of a device by eliminating the installation of an air supply tube, an air supply hose, a suction tube, and a suction hose from the circumference of a drill being the front of the device, and to enhance usability and workability. <P>SOLUTION: A main spindle which is driven into rotation by a power source 10 is of a double-tube structure composed of an internal passage 12a and an external passage 12b. A drill 30 is formed in such a way that a vent hole 33 is formed at the axial center of the drill extending from a shank 31b to an area in the vicinity of a blade 32. The drill is mounted to the tip of the double-tube main spindle 12. Furthermore, hood members 17, 14 which cover the outer periphery of the drill are provided. Moreover, an air supply mechanism 40 which feeds compressed air into the internal passage 12a, and a dust collection mechanism 50 which sucks air from the external passage 12b are connected to the rear end of the double-tube main spindle 12. While the compressed air is supplied via the internal passage 12a to the area around the drill blade, a workpiece is drilled, and produced cutting chips are recovered into the dust collection mechanism 50 by being sucked through the external passage 12b. <P>COPYRIGHT: (C)2012,JPO&INPIT |
