| 摘要 |
PROBLEM TO BE SOLVED: To provide a vertical grinder which can achieve centering easily and in a short time.SOLUTION: A vertical grinder comprises a fulcrum 30 which supports a work-piece W having an outer peripheral surface with a circular section and rotates around a vertical axis Jt, a prove which measures amount of deflection of the outer peripheral surface of the work-piece W and is movable, and a centering device. The fulcrum 30 has a support part 30a which can fix the work-piece 30 in such a manner that the work-piece W is slidable. The centering device has a centering control unit which controls drive of a positioning device 51 on the basis of the value measured by the probe. The positioning device 51 has a first clamp 53 and a second clamp 54 which sandwiches the work-piece W from both sides thereof. The first clamp 53 is slidable along a lateral axis Jy and has a catching arm 55 contacting two portions which are axial symmetry with respect to the lateral axis Jy of the outer peripheral surface of the work-piece W. The position of the catching arm 55 can be controlled. |
