Dynamic Characteristics Analysis for the Headstock of a Vertical Machining Center

Abstract:

Dynamic characteristics of numerical control (NC) machine tools, such as natural frequency and vibration property, directly affect machining efficiency and finished surface quality. In general, low-order natural frequencies of critical components have significant influences on machine tool’s performances. The headstock is the most important component of the machine tool. The reliability, cutting stability, and machining accuracy of a machining center largely depend on the structure and dynamic characteristics of the headstock. First, in order to obtain the natural frequencies and vibration characteristics of the headstock of a vertical machining center, modal test and vibration test in free running and cutting conditions were carried out by means of the dynamic signal collection and analysis system. According to the modal test, the first six natural frequencies of the headstock were obtained, which can not only guide the working speed, but also act as the reference of structural optimization aiming at frequency-shift. Secondly, by means of the vibration test, the vibration characteristics of the headstock were obtained and the main vibration sources were found out. Finally the corresponding vibration reduction plans were proposed in this paper. That provides the reference for improving the performance of the overall unit.

• Periodical: Materials Science Forum (Volumes 836-837)
• Pages: 348-358
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.836-837.348
• Online since: January 2016
• Authors: Zhe Li, Song Zhang*, Yan Chen, Peng Wang, Ai Rong Zhang
• Keywords: Dynamic Characteristic, Modal Test, Vibration Control, Vibration Test

References

[1] Zhang L, Yang W, Chen X, et al. Research on Inherence Properties of CK6310 NC Headstock [J]. Machine Tool & Hydraulics, 2008, 2: 008.

[2] Chen Y S, Wang C S, Yang Y J. Combining vibration test with finite element analysis for the fatigue life estimation of PBGA components [J]. Microelectronics Reliability, 2008, 48(4): 638-644.

DOI: 10.1016/j.microrel.2007.11.006

[3] Kang Y, Sheen G J, Tseng M H, et al. Modal analyses and experiments for engine crankshafts [J]. Journal of sound and vibration, 1998, 214(3): 413-430.

DOI: 10.1006/jsvi.1997.1512

[4] Chen Y, Zhang S, Zhao B, et al. Dynamic Characteristic Analysis for Angularly Deflecting Milling Head of High Speed Gantry Machining Center [J]. Manufacturing Technology & Machine Tool, 2014, 7: 028. (In Chinese).

[5] Dong W X, Hu W L, Li Y X. Research on the vibration control of gear grinding machine based on cutting vibration test [J]. Manufacturing Technology & Machine Tool, 2013 (12). （In Chinese）.

[6] Chen Y, Zhang S, Chen Z, et al. Dynamic/Static Characteristics Analysis and Optimization of Slide of Gantry Machining Center [J]. Manufacturing Technology & Machine Tool, 2014, 8: 029. (In Chinese).

[7] Chen D, Fan J, Zhang F. Dynamic and static characteristics of a hydrostatic spindle for machine tools[J]. Journal of Manufacturing Systems, 2012, 31(1): 26-33.

DOI: 10.1016/j.jmsy.2010.11.006

[8] Zaghbani I, Songmene V. Estimation of machine-tool dynamic parameters during machining operation through operational modal analysis [J]. International Journal of Machine Tools and Manufacture, 2009, 49(12): 947-957.

DOI: 10.1016/j.ijmachtools.2009.06.010

[9] Soshi M, Ishii S, Yamazaki K. A study on the effect of rotational dynamic characteristics of a machine tool spindle drive on milling processes [J]. Procedia CIRP, 2012, 1: 319-324.

DOI: 10.1016/j.procir.2012.04.057

[10] Li B, Hong J, Liu Z. Stiffness design of machine tool structures by a biologically inspired topology optimization method [J]. International Journal of Machine Tools and Manufacture, 2014, 84: 33-44.

DOI: 10.1016/j.ijmachtools.2014.03.005

[11] Altintas Y. Manufacturing automation: metal cutting mechanics, machine tool vibrations, and CNC design [M]. Cambridge university press, (2012).

DOI: 10.1017/cbo9780511843723

[12] Claesson I, Håkansson L. Adaptive active control of machine-tool vibration in a lathe [J]. International Journal of Acoustics and Vibration, 1998, 3(4): 155-162.

DOI: 10.20855/ijav.1998.3.428