| 摘要 |
PURPOSE:To avoid heating at a work point by providing means for controlling a tool cover driven by auxiliary drive means so as to direct an injection port of a water injection nozzle attached to the tool cover to the work point during operation. CONSTITUTION:A unitary structure of a water injecting pipe 18 and a connecting pipe 33 has functions not only of a passage for injecting water, but also of transmitting drive of a ring gear 30 a machining center to a tool cover 16. The ring gear 30 is driven by a pulse motor 32 through a worm wheel 31. Actuation of the pulse motor 32 is controlled by an actuation control system, and as the grinding point of a grindstone 13 in relation to a workpiece is shifted, the tool cover 16 is rotated or stopped so as to properly locate a nozzle port of a water injection nozzle 17 fixed secured to the tool cover 16. Then, grinding is started, with water injected at all times to the grinding point through the water injection nozzle 17. |
