MULTIPLE CONTROL METHOD FOR CONTROLLING CURRENT OF MAIN SHAFT IN CNC MACHINE TOOL

摘要

PURPOSE: A multiple control method for controlling current of a main shaft in a CNC(Computerized Numerical Control) machine tool is provided to maintain constantly a current value of the main shaft by increasing or reducing a transfer speed according to states of processes. CONSTITUTION: A current measuring process is performed to measure the amount of real-time variable current of a main shaft(S100). A CNC machine tool is modeled as the first system having a delay time by formalizing a relationship between various parameter values obtained from a test value of the CNC machine tool(S200). The current of a main shaft is constantly maintained by designing a controller for controlling a transfer speed in order to control the modeled CNC machine tool(S300). Accordingly, the control process can be performed without a variation of load in the main shaft by obtaining the efficient transfer speed.