Paper:
Methods to Measure Wire Deflection in Wire EDM Machining
Jui-Fang Liang and Y. S. Liao
*Department of Mechanical Engineering, National Taiwan University, No.1, Sec.4, Roosevelt Road, Taipei 106, Taiwan
It is well kown that the wire electrode is flexible and will lead to a big lag in wire EDM machining, especially in the middle area of the work-piece. Methods to measure the wire deflection when it passes through the work-piece are studied in this paper. It is found that there is discharge spark first at the upper and lower parts of the wire when it cuts to the edge of the work-piece. The discharge spark appears at the middle of the work-piece a few seconds later. Based on this result, a method coined Camera Picture Analysis (CPA) is proposed to estimate the wire deflection. Another method of cross section measurement by the CCD is proposed to make a cross reference with the CPA method. By applying these two methods, the wire deflection models can be established, and used for the corner cut control of wire-cut EDM to improve accuracy of the machined parts.
- [1] D. F. Dauw, H. Sthioul, R. Delpretti, and C. Tricarico, “Wire Analysis and Control for Precision EDM Cutting,” Annals of the CIRP, Vol.38, Issue 1, pp. 191-194, 1989.
- [2] H. Yamada, N. Mohri, N. Saito, T.Magara, and K. Furutani, “Modal Analysis of Wire Electrode Vibration inWire-EDM,” Int. J. of Electrical Machining, 2, 19-24, 1997.
- [3] A. B. Puri and B. Bhattacharyya, “Modelling and Analysis of the Wire-tool Vibration in Wire-cut EDM,” The Int. J. of Advanced Manufacturing Technology, 141, 295-301, 2003.
- [4] C. Arunachalam, M. Aulia, B. Bozkurt, and P. T. Eubank, “Wire Vibration, Bowing, and Breakage in Wire Electrical Discharge Machining,” J. of Applied Physics, Vol.89, Issue 8, pp. 4255-4262, 2001.
- [5] J. A. Sanchez, L. N. Lopez de Lacalle, and A. Lamikiz, “A Computer-aided System for the Optimization of the Accuracy of the Wire Electro-discharge Machining Process,” Int. J. of Computer Integrated Manufacturing, Vol.17, Issue 5, pp. 413-420, 2004.
- [6] A. B. Puri, and B. Bhattacharyya, “An Analysis and Optimization of the Geometrical Inaccuracy due to the Wire Lag Phenomenon in WEDM,” Int. J. of Machine Tools & Manufacture, Vol.43, pp. 151-159, 2003.
- [7] D. F. Dauw and I. Beltrami, “High-precision Wire EDM by Online Wire Position Control,” Annals of the CIRP, Vol.43, Issue 1, pp. 193-197, 1994.
- [8] N. Kinoshita, M. Fukui, and T. Kimura, “Study on the Wire-EDM: In Process Measurement of Mechanical Behaviour of Electrode Wire,” Annals of the CIRP, Vol.33, Issue 1, pp. 89-92, 1984.
- [9] L. Mingqi, L. Minghui, and X. Guangyao, “Study on the Variations of Form and Position of the Wire Electrode in WEDM-HS,” The Int. J. of Advanced Manufacturing Technology, 25, 929-934, 2004.
- [10] J. A. Sanchez, J. L. Rodil, A. Herrero, L. N. Lopez de Lacalle, and A. Lamikiz, “On the Influence of Cutting Speed Limitation on the Accuracy of Wire-EDM Corner-cutting,” J. of Materials Processing Technology, Vol.182, pp. 574-579, 2007.
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