A thermally stable aerostatic spindle system equipped with self-cooling function

In ultra-precision fly-cutting machining, the aerostatic spindle is the key component, which has significant influence on the machined surface quality. The unbalanced spindle directly affects the machining accuracy. In this article, a prediction model of machining surface topography is proposed which involves the effect of the gas film performance of spindle in microscale. With the Weierstrass function, unstable transient response of the aerostatic spindle system is derived by the motion model of the spindle, which response signal represents the surface profile in the ultra-precision machining. Meanwhile, the experiment is performed with different rotation speed of the spindle. And the effect of the unbalanced aerostatic spindle on the surface generation is discussed in time and frequency domain. The conclusion shows that the similar cyclical surface ripple of the workpiece is independent of the spindle speed, and the rotation speed of the spindle and unbalanced spindle directly affects the machining surface topography. This study is quite meaningful for deeply understanding the influence rule of spindle unbalanced error from the viewpoint of machined surface and vibration frequency.

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Multi-Physics Simulation Based Design and Analysis of a High Speed Aerostatic Spindle and its Performance Assessment

Volume 1A: 34th Computers and Information in Engineering Conference ◽

10.1115/detc2014-34086 ◽

2014 ◽

Author(s):

Siyu Gao ◽

Kai Cheng ◽

Hui Ding

Keyword(s):

High Speed ◽

Integrated Approach ◽

Heat Sinks ◽

Integrated Modelling ◽

Spindle System ◽

Simulation Based Design ◽

Physics Simulation ◽

Speed Up ◽

Analysis Models ◽

Aerostatic Spindle

High speed aerostatic spindles operating at a speed up to 200,000 r/min are a complex product with a multi-physics nature resulted from embedded mechanical-thermal-fluidic-electromagnetic fields. It is much needed to have a comprehensive analysis on the multi-physic interactions within a high speed aerostatic spindle, which is essential for design of the spindles working at much higher speeds and accuracy in various increasingly stringent engineering conditions. This paper presents a multi-physics integrated modelling approach for design and analysis of the high speed aerostatic spindle, including thermal, electromagnetic, mechanical and fluidic analysis models. The heat source, heat transfer mechanism and heat sinks of the spindle system are comprehensively investigated. Furthermore, air film pressure distribution is studied to lead to optimal design and analysis of loading capacity and stiffness of the aerostatic bearings. The multi-physics modelling is implemented using the CFD-FEA integrated approach and validated experimentally. It is shown that the multi-physics integrated modelling is able to simulate the performance characteristics of the spindle system accurately.

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Minimizing Thermal Deformation of Aerostatic Spindle System by Temperature Control of Supply Air

JSME International Journal Series C ◽

10.1299/jsmec.49.606 ◽

2006 ◽

Vol 49 (2) ◽

pp. 606-611 ◽

Cited By ~ 11

Author(s):

Hayato YOSHIOKA ◽

Shimpei MATSUMURA ◽

Hitoshi HASHIZUME ◽

Hidenori SHINNO

Keyword(s):

Temperature Control ◽

Thermal Deformation ◽

Spindle System ◽

Aerostatic Spindle

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Modal analysis of an aerostatic spindle system for ultra-precision machine tools at different spin speeds

Advances in Mechanical Engineering ◽

10.1177/1687814018798528 ◽

2018 ◽

Vol 10 (9) ◽

pp. 168781401879852 ◽

Cited By ~ 1

Author(s):

Peng Chen ◽

Hui Zhuang ◽

Yu Chang ◽

Jianguo Ding ◽

Qidi Zhong ◽

...

Keyword(s):

Flow Field ◽

Rotational Speed ◽

Machine Tools ◽

Natural Frequencies ◽

Mode Shapes ◽

Spindle System ◽

Precision Machine ◽

Ultra Precision ◽

Precision Machine Tools ◽

Aerostatic Spindle

The dynamic properties of aerostatic spindle systems vary with the spindle speed and have a significant impact on the processing quality of ultra-precision machine tools. In this article, using the ICEM CFD, the structured grid model of a large-span scale gas film is built under the condition in which the ratio of the spindle gas film length to the gas film thickness is 13,100. Integral calculation model of spindle and thrust is established and CEL expressions are compiled based on dynamic meshing technique to acquire trajectory of aerostatic spindle system. The degree of freedom method is used to obtain flow field of spindle system. Considering the spindle system as an elastomer, the influence of rotational speed on natural frequencies is studied under the flow field boundary. The results indicate that the former four-order natural frequencies of the aerostatic spindle system will clearly increase as the rotational speed increases. The increase in the fifth- to seventh-order natural frequencies is small, and the eighth-order natural frequency is almost invariable. The flow field has little influence on the mode shapes of the aerostatic spindle system. The former four-order natural frequencies of spindle system decrease considering rotation effects. Rotational speed and rotation effects mainly impact the tilting motion natural frequencies of spindle and thrust.

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Dynamic performance analysis and quantitative evaluation for ultraprecision aerostatic spindle

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405419855239 ◽

2019 ◽

Vol 234 (1-2) ◽

pp. 218-228

Author(s):

Ruocheng Wei ◽

Chenhui An ◽

Zhenzhong Wang ◽

Qiao Xu ◽

Xiangyang Lei ◽

...

Keyword(s):

Transient Analysis ◽

Dynamic Performance ◽

Response Analysis ◽

Quantitative Index ◽

Medium Frequency ◽

Dynamic Simulations ◽

Machined Surface ◽

Spindle System ◽

Aerostatic Spindle ◽

Dynamic Performance Analysis

For optics used in high-power laser beams, high accuracy requirements in full spatial frequency must be fulfilled. Among them, the allowable root mean square value is less than 5 nm in the PSD1 band. In order to evaluate the dynamic performance of the spindle system and put forward a quantitative index, a novel accurate model of the spindle system was built and a series of dynamic simulations were performed. Harmonic response analysis reveals natural frequencies and frequency response functions. Transient analysis indicates vibration waveforms of the tool-tip. Furthermore, by analyzing surface topography, it can be found that the medium-frequency waviness in the machined surface matches the vibration waveform. Obviously, the medium-frequency waviness is generated by the modal vibration of the spindle system. So that a quantitative index for the aerostatic spindle is proposed: when the amplitude of vibration in transient analysis is smaller than 8 nm, the allowable error in the PSD1 band can be fulfilled.

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A Thermally Stable High Speed Spindle System Equipped with Self-Cooling Function

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.523-524.527 ◽

2012 ◽

Vol 523-524 ◽

pp. 527-531 ◽

Cited By ~ 1

Author(s):

Yuuki Tamura ◽

Hiroshi Sawano ◽

Hayato Yoshioka ◽

Hidenori Shinno

Keyword(s):

High Speed ◽

High Performance ◽

Thermal Deformation ◽

Simple Structure ◽

Thermal Characteristics ◽

Research Papers ◽

Cooling Systems ◽

Spindle System ◽

Air Turbine ◽

Cooling Function

Demands for high speed and high precision machining technologies have recently increased in a variety of industries. In general, a high speed spindle system can realize such high performance machining, however it generates a large amount of heat that causes thermal deformation. However, few research papers on thermal deformation-minimized spindle systems have been published so far. This paper presents a newly developed spindle system driven by a built-in air turbine. The developed spindle system has a self-cooling function with the air turbine. In addition, the spindle system has a compact and simple structure compared to the conventional spindle cooling systems. The air turbine was designed to improve the cooling and torque performances. Actual spindle rotational experiments were performed in order to evaluate rotating accuracy and thermal characteristics of the spindle system during rotating at a high speed. Experimental results confirmed that the spindle system can minimize thermal deformation of the spindle by the self-cooling function.

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Thermal Deformation Control of Aerostatic Spindle System Using Temperature Controlled Supply Air

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C ◽

10.1299/kikaic.70.3605 ◽

2004 ◽

Vol 70 (700) ◽

pp. 3605-3610 ◽

Cited By ~ 3

Author(s):

Hayato YOSHIOKA ◽

Shimpei MATSUMURA ◽

Hitoshi HASHIZUME ◽

Hidenori SHINNO

Keyword(s):

Thermal Deformation ◽

Spindle System ◽

Deformation Control ◽

Temperature Controlled ◽

Aerostatic Spindle

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Investigation of the V4+-Centre in 6H- and 4H-SIC by the Method of Spectral-Hole Burning

MRS Proceedings ◽

10.1557/proc-512-369 ◽

1998 ◽

Vol 512 ◽

Author(s):

C. Hecht ◽

R. Kummer ◽

A. Winnacker

Keyword(s):

Electronic Properties ◽

Room Temperature ◽

Hole Burning ◽

Band Offset ◽

Spectral Hole Burning ◽

Type Ii ◽

Thermally Stable ◽

Spectral Hole

ABSTRACTIn the context of spectral-hole burning experiments in 4H- and 6H-SiC doped with vanadium the energy positions of the V4+/5+ level in both polytypes were determined in order to resolve discrepancies in literature. From these numbers the band offset of 6H/4H-SiC is calculated by using the Langer-Heinrich rule, and found to be of staggered type II. Furthermore the experiments show that thermally stable electronic traps exist in both polytypes at room temperature and considerably above, which may result in longtime transient shifts of electronic properties.

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