Online real-time cutter breakage monitoring method

An online real-time cutter breakage monitoring method, using a vibration signal capturing module and a monitoring subsystem, and the monitoring subsystem being electrically coupled to the vibration signal capturing module, and the method comprising the steps of:

• capturing a plurality of cutting vibration acceleration signals when a CNC machine tool performs a cutting;
• comparing the cutting vibration acceleration signals in three consecutive time periods, and retrieving a maximum value and an average value of the cutting vibration acceleration signal in each time period;
• comparing the maximum value of the cutting vibration acceleration signals in a second time period with the average value of the cutting vibration acceleration signals in a first time period to obtain a difference value;
• observing the difference value, and determining whether the difference value matches a cutter breakage characteristic to output a first cutter breakage signal;
• defining an idling critical value, and calculating the average value of the cutting vibration acceleration signals in a third time period;
• determining whether average value of the cutting vibration acceleration signals of the third time period and thereafter is smaller than the idling critical value to output a second cutter breakage signal;
• using the monitoring subsystem to receive the first cutter breakage signal and the second cutter breakage signal simultaneously to determine an occurrence of a cutter breakage of the CNC machine tool;
• and
• outputting a shutdown signal to the CNC machine tool to shut down an operation if both the first cutter breakage signal and the second cutter breakage signal are received by the monitoring subsystem.