| 摘要 |
PURPOSE:To detect a machining start position correctly and reduce the dispersion of machining time by bringing a finish-grinding wheel into contact with the inner cylindrical face of a workpiece to perform the centering of a honing tool, then expanding a pair of rough-grinding wheels to bring them into contact with the inner cylindrical face, and applying a current thereto. CONSTITUTION:At the time of honing the inner surface of the machined hole B of a workpiece W, an expanding pressure regulating device is controlled to expand each finish-grinding wheel with low expanding pressure and to press each finish-grinding wheel to the inner surface of the machined hole B, thus centering a honing tool 3. After contracting each finish-grinding wheel, a pair of rough-grinding wheels 7A, 7B are expanded and brought into contact with the inner surface of the machined hole B. The current application is confirmed by an ampere meter 25, and a machining start position is detected. This detection signal is sent to a control device 27 from the ampere meter 25. The rotation and reciprocating motion of a honing head, and the expanding pressure regulating device are controlled by the control device 27 to perform honing to the inner surface of the machined hole B. |
