Dynamic reliability of thermally deduced positioning precision of ball screw systems based on random moving difference method

This paper deals with the precision modelling of the ball screw unit’s thermal behaviour in the turning centre and its impact on the tool head positioning error. The error components along controllable axes X and Z are described in detail using an FE model integrating the changes in thermal and force loads and deformations occurring during the motion of the nut as a heat source. The impact of the nut work cycle on the thermal deformations of the ball screw and the displacements of the slideways and the screw points along both the axes and on carriage positioning precision is demonstrated.

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Thermal Analysis of a Ball Screw by ADI Finite Difference Method

Transactions of the Korean Society of Mechanical Engineers A ◽

10.3795/ksme-a.2018.42.11.975 ◽

2018 ◽

Vol 42 (11) ◽

pp. 975-984 ◽

Cited By ~ 1

Author(s):

Bog-Ki Min ◽

Chun-Hong Park ◽

Sung-Chong Chung

Keyword(s):

Thermal Analysis ◽

Finite Difference ◽

Finite Difference Method ◽

Difference Method ◽

Ball Screw

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The positioning precision analysis of the ball screw drive system

2011 International Conference on Mechatronic Science, Electric Engineering and Computer (MEC) ◽

10.1109/mec.2011.6025519 ◽

2011 ◽

Author(s):

Huiduan Zhang ◽

Junling Sun

Keyword(s):

Drive System ◽

Ball Screw ◽

Precision Analysis ◽

Positioning Precision ◽

Screw Drive ◽

Ball Screw Drive

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Modeling of the rotor-bearing system and dynamic reliability analysis of rotor’s positioning precision

Proceedings of the Institution of Mechanical Engineers Part O Journal of Risk and Reliability ◽

10.1177/1748006x20964025 ◽

2020 ◽

pp. 1748006X2096402

Author(s):

Yimin Zhang ◽

Yongzhen Liu

Keyword(s):

Cumulative Distribution ◽

Dynamic Equations ◽

System Response ◽

Stochastic Dynamic ◽

State Function ◽

Positioning Precision ◽

Dynamic Reliability ◽

Rotor Bearing ◽

First Four Moments ◽

Bearing System

On the basis of the classical two degree of freedom (2-DOF) rotor-bearing system, the stochastic dynamic equations are solved and the dynamic reliability of the rotor’s positioning precision is examined in this paper. Firstly, the stochastic dynamic equations are converted to several deterministic dynamic equations by orthogonal polynomial approximation method. The contact uncertainty coefficient is described by Bernoulli distribution and the instantaneous contact probability of the ball-inner race contact of the rolling bearing is obtained. Then the state function of the system is defined and the statistical fourth moment method is adopted to determine the first four moments of the system response and state function. Edgeworth series technique is used to approach the cumulative distribution function (CDF) of the maximum displacement of the response and the system state function. Different parameters effects on the characteristics of the responses and the reliability of the system are investigated. The comparisons of the results obtained from the Monte Carlo simulation (MCS), the previous study and the present study illustrate the effectiveness of the study.

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Dynamic reliability analysis of angular contact ball bearings in positioning precision

Proceedings of the Institution of Mechanical Engineers Part O Journal of Risk and Reliability ◽

10.1177/1748006x20933506 ◽

2020 ◽

Vol 234 (6) ◽

pp. 723-734

Author(s):

Yimin Zhang ◽

Jianguo Gu

Keyword(s):

Dynamic Response ◽

Geometric Parameters ◽

State Function ◽

Ball Bearings ◽

Nonlinear Dynamic Model ◽

Motion Error ◽

Positioning Precision ◽

Mean Values ◽

Dynamic Reliability ◽

Stochastic Perturbation Method

Bearings are the core components in various kinds of rotating machineries. With the increasing demand of reliable bearings in precision equipment, it is of great significance to analyze the motion error of bearings. In this article, a nonlinear dynamic model of angular contact ball bearings installed in pairs is constructed to describe its response characteristics. The definition of a failure mode in matched bearings is that the dynamic response of each inner race is larger than the allowed axial runout. This article introduces a feasible approach to evaluate the reliability of positioning precision of matched bearings with random geometric parameters. The statistical moments of dynamic response are calculated using stochastic perturbation method. The probability distribution function of state function relating to positioning precision is approached by Edgeworth series, from which the reliability and sensitivity are obtained. A pair of 7206B bearings is taken as an application instance of the proposed method. Monte Carlo simulation is employed to provide a benchmark on which to verify the precision and efficiency of the proposed method. In addition, the effects of mean values and variances of random geometric parameters on the positioning precision are analyzed, respectively.

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