| 摘要 |
PROBLEM TO BE SOLVED: To provide a drill furnished with a chamfering mechanism to chamfer an edge of a hole worked by a cutting blade of a drill part, which reduces a working cost of a built-in hole for the chamfering mechanism provided on a drill main body while avoiding upsizing of the chamfering mechanism. SOLUTION: The built-in hole 6 workable by a cutting tool to open on an outer periphery of a land part 7 is provided on the drill main body 1, a cartridge 21 to be fixed on the drill main body 1 by a fixing means 24 is inserted into this built-in hole 6, a chamfering tip 22 furnished with a chamfering blade to work an edge of the hole drilled on a cutting material by the cutting blade of the drill part is slidably inserted into a guide groove 21a formed on the cartridge in the drill radial direction, and the chamfering tip 22 is projected to an outer periphery of the drill main body 1 up to a position regulated by a projecting quantity limiting means 25 by receiving energizing force from an elastic body on an inner end in the drill diametrical direction of this chamfering tip 22. COPYRIGHT: (C)2008,JPO&INPIT
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