Paper:

# Compensation for Thermal Deformation of a Compact Lathe in Cutting Operations Using a Coolant Fluid with Temperature Measurements at a Few Specific Points

## Yoshiaki Ishino^{*}, Hiroshi Tachiya^{**,†}, and Yoshiyuki Kaneko^{*}

^{*}Technical Development, Takamatsu Machinery Co., Ltd.

1-8 Asahigaoka, Hakusan, Ishikawa 924-8558, Japan

^{**}Division of Mechanical Science and Engineering, Kanazawa University, Kanazawa, Japan

^{†}Corresponding author

We previously designed a compact computer numerical control (CNC) lathe that arranges its heat sources so as to reduce their thermal deformation. However, a compact lathe often undergoes large deformation owing to unexpected thermal conditions arising out of the work environment or from operation of the lathe itself. Hence, we propose a method to determine equations predicting thermal deformation in a CNC lathe from temperatures measured at a few specific points. These equations enable one to effectively compensate for lathe thermal deformation. However, they cannot be applied to cutting operations involving a coolant fluid because the coolant fluid flow may lead to a complicated thermal deformation scenario. In this study, we attempted to more accurately compensate for thermal deformation, for cutting operations involving a coolant fluid, by adding simple calibration coefficients to the prediction equations. We applied the modified equations to a numerically controlled controller and validated our approach for cutting operations using a coolant fluid under various conditions.

*Int. J. Automation Technol.*, Vol.13, No.4, pp. 527-538, 2019.

- [1] T. Moriwaki, E. Shamoto, and M. Kawano, “Estimation of Thermal Deformation of Machine Tool by Applying Neural Network (Improvement of Estimation Accuracy by Utilizing Time-Series Data of Temperature on Machine Surfaces),” Trans. of the Japan Society of Mechanical Engineers, Series C, Vol.61, No.584, pp. 1691-1696, doi:10.1299/kikaic61.1691, 1995 (in Japanese).
- [2] I. Tanabe, Y, Kaneko, Y. Saitoh, H. Mori, and K. Urano, “Simple and Intelligent Control Using Neural Network about Thermal Deformation of a Machine tool,” Trans. of the Japan Society of Mechanical Engineers, Series C, Vol.70, No.698, pp. 2954-2960, doi:10.1299/kikaic.70.2954, 2004 (in Japanese).
- [3] Y. Kakino and K. Okushima, “Study on Thermal Deformations of Machine Tools (4th Report: Thermal Deformations Due to External Heat Sources),” The Japan Society for Precision Engineering, Vol.40, No.12, pp. 1105-1110, doi: 10.2493/jjspe1933.40.1105, 1974 (in Japanese).
- [4] K. Nakanishi, M. Sawada, and J. Sakamoto, “Influence of Heat in Multi-Tasking Machine Bed and its Analytical Technique,” Int. J. Automation Technol., Vol.12, No.2, pp. 254-261, 2018.
- [5] Z. Yang, M. Sun, W. Li, and W. Liang, “Modified Elman Network for Thermal Deformation Compensation Modeling in Machine Tools,” Int. J. of Advanced Manufacturing Technology, Vol.54, pp. 669-676, doi:10.1007/s00170-010-2961-3, 2011.
- [6] Q. Guo, J. Yang, and H. Wu, “Application of ACO-BPN to Thermal Error Modeling of NC Machine Tool,” Int. J. of Advanced Manufacturing Technology, Vol.50, pp. 667-675, doi:10.1007/s00170-010-2520-y, 2010.
- [7] H. Zhao, J. Yang, and J. Shen, “Simulation of Thermal Behavior of a CNC Machine Tool Spindle,” Int. J. of Machine Tools & Manufacture, Vol.47, Issue 6, pp. 1003-1010, 2007.
- [8] C. Brecher and A. Wissmann, “Compensation of Thermo-Dependent Machine Tool Deformations Due to Spindle Load Based on Reduce Modeling Effort,” Int. J. Automation Technol., Vol.5, No.5, pp. 679-687, 2011.
- [9] T. Shinshi, K. Sato, and A. Shimokohbe, “A Compact Aerostatic Spindle Integrated with an Axial Positioning Actuator for Micro and Ultra-Precision Machine Tools,” Int. J. Automation Technol., Vol.2, No.1, pp. 56-63, 2007.
- [10] H. Mizoguchi, M. Iwakiri, Y. Ido, and H. Shinno, “A Real-Time Measuring Method of Spindle Center Transition for NC Lathe,” Int. J. Automation Technol., Vol.2, No.6, pp. 486-491, 2008.
- [11] H. Zhao, J. Yang, and J. Shen, “Simulation of Thermal Behavior of a CNC Machine Tool Spindle,” Int. J. of Machine Tools & Manufacture, Vol.47, pp. 1003-1010, doi: 10.1016/i.ijmachtools.2006.06.018, 2007.
- [12] J. Xia, Y. Hu, W. Bo, and T. Shi, “Research on Thermal Dynamics Characteristics and Modeling Approach of Ball Screw,” Int. J. of Advanced Manufacturing Technology, Vol.43, pp. 421-430, doi:10.1007/s00170-008-1723-y, 2009.
- [13] C. Endo, “Small Processing Machinery Effectiveness in Micropart Processing and Factory Construction with Desktop Production Equipment,” Int. J. Automation Technol., Vol.4, No.2, pp. 155-159, 2010.
- [14] T. Ogawa, “Building of Efficient, Energy-Saving Lines with an Extremely-Compact Machining Center and CNC Lathe,” Int. J. Automation Technol., Vol.4, No.2, pp. 150-154, 2010.
- [15] N. Suzuki, Y. Morimoto, K. Takasugi, R. Kobayashi, R. Hirono, Y. Kaneko, and Y. Tokuno, “Development of Desktop Machine Tool with Pipe Frame Structure,” Int. J. Automation Technol., Vol.9, No.6, pp. 720-730, doi: 10.20965/ijat.2015.p0720, 2015.
- [16] Y. Suzuki, “Mizuho Industry Focus – The Current State and Problem of Japanese Machine Tool,” Industrial Morgue of Mizuho Corporate Bank, p. 17, 2010 (in Japanese).
- [17] H. Kato, K. Shintani, and K. Iwata, “High-Speed Milling Using a Developed Desktop Machine Tool,” Int. J. Automation Technol., Vol.4, No.2, pp. 103-109, 2010.
- [18] Y. Okazaki, “Desk-Top Milling Machine Equipped with Ultra-High Speed Spindle (2nd Report),” Proc. of JSPE Semestrial Meeting 2001 Spring Meeting, 2001.
- [19] Y. Kaneko, H. Tachiya, H. Tamura, H. Shinjo, and M. Isobe, “Simple and effective method to compensate thermal deformation of a machine tool by deriving its approximate equation (application under the continuous operating condition),” The Japan Society for Precision Engineering, Vol.73, No.726, pp. 371-378, 2007 (in Japanese).
- [20] H. Tachiya, Y. Kaneko, T. Aramoto, H. Shinjo, and Y. Miyazaki, “Approximation of Thermal Deformation Behaviour of a Machine Tool to Improve its Process Precision,” Key Engineering Materials, Vols.345-346, pp. 181-184, doi:10.4028/www/scientific.net/KEM.345-346.181, 2007.
- [21] H. Tachiya, H. Hirata, T. Ueno, Y. Kaneko, K. Nakagaki, and Y. Ishino, “Evaluation of and Compensation for Thermal Deformation in a Compact CNC lathe,” Int. J. Automation Technol., Vol.6, No.2, pp. 1124-1132, 2012.
- [22] H. Tachiya, H. Hirata, T. Suma, Y. Kaneko, K. Nakagaki, and Y. Ishino, “Compensation of Thermal Deformation of Compact CNC Lathe by Measuring Temperatures at a Few Points,” The Japan Society for Mechanical Engineers, Series C, Vol.79, No.804, pp. 2960-2974, 2013 (in Japanese).
- [23] J. Mayr, M. Gebhardt, B. B. Massow, S. Weikert, and K. Wegener, “Cutting Fluid Influence on Thermal Behavior of 5-axis Machine Tools,” Procedia CIRP, Vol.14, pp. 395-400, doi:10.1016/j.procir.2014.03.085, 2014.
- [24] P. Blasera, F. Pavliceka, K. Mori, J. Mayrc, S. Weikertc, and K. Wegener, “Adaptive Learning Control for Thermal Error Compensation of 5-axismachine Tools,” J. of Manufacturing Systems, Vol.44, Part 2, pp. 302-309, 2017.

This article is published under a Creative Commons Attribution-NoDerivatives 4.0 International License.