| 1. |
- Li, Yunsong, et al.
(författare)
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Dynamics modeling and modal experimental study of high speed motorized spindle
- 2017
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Ingår i: Journal of Mechanical Science and Technology. - : Springer Science and Business Media LLC. - 1738-494X .- 1976-3824. ; 31:3, s. 1049-1056
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents a dynamical model of high speed motorized spindles in free state and work state. In the free state, the housing is modeled as a rotor with equivalent masses including bearing pedestals, motor stator and rear end cover. As a consequence, a double rotor dynamics can be modeled for high speed motorized spindles by a bearing element which connects the housing and bearing pedestals. In the work state, the housing is fixed and the system becomes a bearing-rotor dynamical model. An excitation-measurement test in the free state is designed to analyze the cross spectral density and auto spectral density of input and output signals. Then the frequency response function of system and coherence function of input and output signals which are used to analyze the inherent characteristics of the double- rotor model can be obtained. The other vibration test in the work state is designed to research the dynamical supporting characteristics of bearings and the effects from bearings on the inherent characteristics of the system. The good agreement between the experimental data and theoretical results indicates that the dynamical model in two states is capable of accurately predicting the dynamic behavior of high speed motorized spindles.
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| 2. |
- Shan, Wentao, et al.
(författare)
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A novel experimental research on vibration characteristics of the running high-speed motorized spindles
- 2013
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Ingår i: Journal of Mechanical Science and Technology. - : Springer Science and Business Media LLC. - 1738-494X .- 1976-3824. ; 27:8, s. 2245-2252
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Tidskriftsartikel (refereegranskat)abstract
- Because of the complicated running condition and many unpredicted factors such as unmodelled dynamics and external disturbances, the fault analysis of the high-speed motorized spindle is proved difficult. In this paper, a novel experimental method is proposed to research the vibration characteristics of the running high-speed motorized spindle. The method consists of four steps. Firstly, the vibration signal measurement and processing system are built according to data collector and signal analysis software, and then, the vibration signal of the spindle extracted from sophisticated experimental environment is studied by using harmonic wavelet transform for its advantages, such as ultra-narrow band, high resolution detection and ability of extracting weak signal. After that, local frequency domain zooming technique of harmonic wavelet packet is employed to study the vibration spectrum of the spindle at eight different rotating speeds. Furthermore, the axis orbit of the rotor is purified successfully, which can serve as verification basis for subsequent on-site fault diagnosis. Finally, a comparative analysis of eight different vibration signals under the same load but different speeds condition is carried out, the spectral components are classified into two types: the repeated ones and the regular ones. The accordance between experimental results and theoretical analysis suggests that the proposed method in this paper is effective.
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