| 摘要 |
PURPOSE:To avoid secondary fault such as damage of tool, defective work, damage of machine, etc. thus to improve safety by separating the work and the gear cutting tool upon exceeding of detected acceleration of spindle over setting level and stopping each feeding shaft. CONSTITUTION:Upon exceeding of acceleration detected through acceleration detecting means 30, 31, 32 over predetermined level, an abnormal acceleration signal is fed to NC device 15 to stop rotation of an axial feeding screw shaft 25 thus to stop feeding in axial direction while a radial feeding shaft 26 is fed in the direction for separating the work from a hob 1 then stops. Furthermore, the table shaft is stopped immediately to maintain current condition of hob shift shaft to stop entirely upon finish of feed hold retract. Consequently, secondary fault such as damage of tool, defective work damage of machine, etc. can be avoided. |
