| 摘要 |
PURPOSE:To eliminate positioning errors, conduct operations efficiently, and perform correct positioning even if grindstones have been abraded by stopping grindstone bed feed motors in response to a detection signal so as to position the grindstones at the abrasion starting condition. CONSTITUTION:Feed screws 20, 20a screwed longitudinally into grindstone beds 13, 13a provided with grindstones 16, 16a are connected to grindstone bed feed motors 24, 24a through friction clutches 21, 21a. Next, reduction or stoppage of the revolution of the feed screws 20,20a due to a slip of the friction clutches 21, 21a caused by a contact between the grindstones 16, 16a and a cutter is deteced by detectors 35, 35a, and the grindstone bed feed motors 24, 24a are stopped by the detection signal so as to position the grindstones 16, 16a at the abrasion starting condition. |
