Enhancement of the fitness for high speed and high precision machining center

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A dynamic synthesis model, which consist of a base, column, feed drive, and floor foundation, is developed for the enhancement of the performance of machining centers. By using this model, several countermeasures to enhance the dynamic performance are investigated. A thermal synthesis model is investigated for the fitness enhancement as well.(1)For the enhancement of the dynamic fitness, design strategies for anti-vibration of base-column-feed drive system are proposed. Improvement of the installation, reduction of the column mass, and driving scheme at center of gravity can provide good positioning accuracy.(2)By adding IIR filters in the velocity loop of the CNC-Servo system, positioning accuracy is improved without changing machine stricture. Second order der IIR filters are investigated to show their anti-vibration mechanism and performance. In the case of lower damping system, robustness is found to be major problems.(3)Dual actuation driving systems are investigated whether it can improve the dynamic performance of the total machine. The dual actuation system can improve the positioning accuracy without much increment of weight and cost, so it can contribute to the enhancement of the dynamic fitness.(4)Thermal synthesis is difficult to be established. In a ball screw on which thermal recourse moves and a high speed spindle, typical temperatures and thermal displacements are measured. Thermal distributions and displacements are modeled as the product of thermal modes and time functions in the stationary conditions.