Effect of bearing preload on the dynamic characteristics of the spindle-bearing system

Ceramic bearings have a good dynamic output performance under an ultra-high, ultra-low temperature due to their small deformation property. Based on the Harris and Palmgren empirical equation, this article establishes the thermal transfer model of a ceramic motorized spindle. The thermal deformation of a ceramic angular contact ball bearing is calculated. A dynamic and thermal coupling model of the ceramic motorized spindle is built using the Hertz contact theory, which can determine the optimal preload force under different rotating speed conditions. The influence of different temperatures, preload, and rotation speeds on the bearing vibration characteristics was studied. The accuracy of the dynamic and thermal coupling model was verified by the motorized spindle experimental platform. The results show that the thermal deformation of the bearing is an important influencing factor for the output of the dynamic characteristics. Considering the thermal displacement of the bearing, the simulation accuracy of the ceramic motorized spindle-bearing system is in good agreement with the experimental results. By adjusting the bearing preload, the parameters of the rotating speed can effectively reduce the temperature rise and suppress the vibration. The spindle-bearing system model provides a theoretical basis for the dynamic development of a high-speed ceramic bearing.

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Prediction of the Structural Dynamic Behavior of High Speed Turning Machine Spindles

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.555.567 ◽

2014 ◽

Vol 555 ◽

pp. 567-574

Author(s):

Constantin Dogariu ◽

Doru Bardac

Keyword(s):

Finite Element ◽

Dynamic Behavior ◽

Dynamic Characteristics ◽

High Speed ◽

3D Model ◽

Element Model ◽

Structural Dynamic ◽

Spindle Bearing ◽

Machine Spindle ◽

Bearing System

This paper presents a method to investigate the dynamic behavior of a turning high-speed spindle system. The machine tool main spindle unit is focused on direct driven spindle units for high-speed and high performance cutting. This paper analyzes the static behavior for a turning machine spindle and presents some activities to improve the CAD model for such complex systems. The proposed models take into account the spindle with the bearing detailed system. The analysis was performed during the design activity and was based on Finite Elements Method. Starting from the 3D model, using FEM done by means of ANSYS analysis, structural dynamic behavior was evaluated. The aim of this paper is to develop a finite element model of the machine spindle system and use this method for design optimization. The 3D model was designed using the Solidworks CAD software. In order to obtain accurate dynamic characteristics of the spindle-bearing system during the design stage, the finite element model is simulated using dedicated software, and a method in which springs and damping units imitate bearing support. The proposed method can predict the regular pattern in which bearing stiffness and bearing span affect natural frequency and harmonic response. The research demonstrates that this method predicts the dynamic characteristics of the spindle-bearing system therefore it can be a reference for dynamic optimization design of spindle-bearing systems in turn-milling centers. The static analysis was presented in another paper. The thermal analysis will be presented in a future paper.

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Dynamic Characteristics of Spindle-Bearing System in Machine Tools : 2nd Report, Mathematical Expression of Spindle-Bearing System and its Application

Bulletin of JSME ◽

10.1299/jsme1958.28.2460 ◽

1985 ◽

Vol 28 (244) ◽

pp. 2460-2466 ◽

Cited By ~ 2

Author(s):

Masaomi TSUTSUMI ◽

In Sung CHUNG ◽

Yasunori MURAKAMI ◽

Yoshimi ITO

Keyword(s):

Dynamic Characteristics ◽

Machine Tools ◽

Mathematical Expression ◽

Spindle Bearing ◽

Bearing System

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Dynamic modeling and vibration response analysis of a synchronous motorized spindle with inclined eccentricity

Journal of Vibration and Control ◽

10.1177/10775463211023350 ◽

2021 ◽

pp. 107754632110233

Author(s):

Wei Feng ◽

Kun Zhang ◽

Baoguo Liu ◽

Weifang Sun ◽

Sijie Cai

Keyword(s):

Analytical Method ◽

Vibration Response ◽

Mass Force ◽

Motorized Spindle ◽

Dynamic Displacement ◽

Unbalanced Mass ◽

Unbalanced Magnetic Pull ◽

Spindle Bearing ◽

Mass Eccentricity ◽

Bearing System

The air-gap eccentricity will produce unbalanced magnetic pull and cause vibrations and noises in a motor. In this study, the dynamic behavior of a synchronous motorized spindle with inclined eccentricity is investigated. A semi-analytical method is proposed to model the unbalanced magnetic pull and the electromagnetic torque of a rotor with inclined eccentricity, and the semi-analytical method is verified by the finite element method. The dynamic model of a spindle-bearing system is built by taking the centrifugal force and gyroscopic effects into account. Then, the vibration response of dynamic displacement eccentricity, inclined eccentricity including displacement eccentricity and angle eccentricity, rotating speed, and unbalanced mass eccentricity in both time domain and frequency domain are simulated and analyzed. The results show that the eccentricities can lead to fluctuations in amplitudes of the dynamic displacement response and the angle response. The frequency components of the dynamic responses are the combination of rotating frequency, VC frequency, and power frequency. It is indicated that the coupling interactions of bearing forces, unbalanced mass force, and unbalanced magnetic pull have an obvious effect on the spindle-bearing system.

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Assessment of Bearing Dynamic Characteristics by Numerical Modeling with Effects of Oil Film and Centrifugal Deformation

Mathematical Problems in Engineering ◽

10.1155/2018/1619297 ◽

2018 ◽

Vol 2018 ◽

pp. 1-13

Author(s):

Jie Yu ◽

Wei Yuan ◽

Songsheng Li ◽

Wenbing Yao

Keyword(s):

Contact Angle ◽

Dynamic Characteristics ◽

Axial Load ◽

Rotation Speed ◽

Great Influence ◽

Static Model ◽

Contact Load ◽

Oil Film ◽

Spindle Bearing ◽

Ring Rotation

This paper developed a modified quasi-static model (MQSM), considering the oil film thickness between the bearing parts and the centrifugal deformation of the inner ring, and contrasting with traditional quasi-static model (TQSM), to analyze the dynamic characteristics of spindle bearing. The model was verified with the experimental results. A systematic parametric analysis was made to investigate the influence of applied load, inner ring rotation speed (ni), and the radius coefficient of groove curvature (RCR) on the contact load, contact angle, and heat generating rate. The results show that there is a smaller influence on the contact load, contact angle, and heat generation of bearing with the changes of ni and axial load (Fa) of bearing in the case of MQSM and TQSM. But the radial load (Fr) and RCR have great influence on this.

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