| 摘要 |
PURPOSE:To increase grinding accuracy, by using two drill holding units, a first chuck and a second chuck for holding a drill at two positions, a shank and a body, and relatively pressing the tip of the drill to a grinding stone. CONSTITUTION:A drill 14 is securely held at its shank 26 and a body 34 by that they are gripped by a first chuck 16 and a second chuck 18 and a grinding stone 134 is pressed to the tip portion 52 of the drill for grinding. Further, the drill 14 is ground by being griped by a holder 12 in such a state that the a projecting length from the second chuck 18 and a phase of a relative rotation are positioned at a prescribed size and phase by a rotational position determining unit 36 mounted on a grinding machine main body 10. On addition, a rotational operation lever 132 causes a mounting guide block to which the holder 12 is inserted to move by a guidance of a guide block for grinding an R portion of the tip portion 52. With the arrangement, the drill 14 can be accurately ground without the need for excellent skill. |
