| 摘要 |
PURPOSE:To detect abnormality of a tool for its wear, damage or the like, by providing an electrical contact to the main spindle of a machine tool, inserting a series circuit between said contact and the tool and detecting voltage. CONSTITUTION:A series connection circuit of a power source 8 and resistance 9 is placed between a main spindle 3 and tool 6 of a machine tool, and voltage across both ends of said resistance 9 is detected. This detected output is frequency analyzed, and amplitude of a resonance frequency component between tools 6, 7 is detected through a band pass filter then compared with a predetermined reference value to detect abnormality of the tool. Further thermoelectromotive force generated between the tools 6, 7 is detected by voltage obtained from the both ends of the resistance 9, then an entangled chip between the tools 6, 7 can be detected. In this way, abnormality of the tool for wear and the like can be detected. |
