Dynamic Characteristics of Motorized Spindle With Tandem Duplex Angular Contact Ball Bearings

2019 ◽  
Vol 141 (6) ◽  
Author(s):  
Shengye Lin ◽  
Shuyun Jiang

Abstract The purpose of this study is to investigate the dynamics of motorized spindle, in which the tilting effect of tandem duplex angular contact ball bearing is considered. First, the quasi-static model of the duplex angular contact ball bearing is developed based on the Jones's bearing model. Then, the model is numerically solved using the Newton–Raphson method to obtain 16 stiffness coefficients (including the tilting ones). Later, a modified transfer matrix method is used to establish the dynamic model of the motorized spindle system with 16 stiffness coefficients. Finally, experiments have been performed to detect the stiffness of the tandem duplex angular contact ball bearing and the unbalance response of the motorized spindle. Results show that the modified transfer matrix method can be used to analyze the dynamic behavior of the motorized spindle supported on tandem duplex angular contact ball bearings, the tilting effect of the tandem duplex angular contact ball bearing affects the dynamic behaviors of the motorized spindle, and the theoretical dynamic characteristics using the proposed model agree with the experimental ones.

2018 ◽  
Vol 141 (3) ◽  
Author(s):  
Shengye Lin ◽  
Shuyun Jiang

This paper studies the stiffness characteristics of preloaded duplex angular contact ball bearings. First, a five degrees-of-freedom (5DOF) quasi-static model of the preloaded duplex angular contact ball bearing is established based on the Jones bearing model. Three bearing configurations (face-to-face, back-to-back, and tandem arrangements) and two preload mechanisms (constant pressure preload and fixed position preload) are included in the proposed model. Subsequently, the five-dimensional stiffness matrix of the preloaded duplex angular contact ball bearing is derived analytically. Then, an experimental setup is developed to measure the radial stiffness and the angular stiffness of duplex angular contact ball bearings. The simulated results match well with those from experiments, which prove the validity of the proposed model. Finally, the effects of bearing configuration, preload mechanism, and unloaded contact angle on the angular stiffness and the cross-coupling are studied systematically.


Author(s):  
Shuang Huang ◽  
Xinfu Chi ◽  
Yang Xu ◽  
Yize Sun

Focusing on tufting machine type DHUN801D-400, the complex dynamic model of coupling shaft system is built by using Riccati whole transfer matrix method, and the natural frequencies and mode shapes are analyzed. First, the components of coupling shafts system in tufting machine are introduced. Second, the structures of coupling shafts system are discretized and simplified. Third, the transfer matrix is constructed, the model is solved by using Riccati whole transfer matrix method, and then natural frequencies and mode shapes are obtained. Finally, the experimental results are quoted to demonstrate the applicability of the model. The results indicate that the Riccati whole transfer matrix method is well applicable for modeling the dynamics of complex multi-rotor systems.


2020 ◽  
Vol 319 ◽  
pp. 01001
Author(s):  
Anfeng Zhou ◽  
Daokui Li ◽  
Shiming Zhou ◽  
Da Cui ◽  
Xuan Zhou

In order to ensure the safety of the missile-canister system in silo during the earthquake, a modified transfer matrix method is provided to study the dynamic characteristics of the system. Firstly, a discrete viscoelastic connected double-beam model is developed taking account of the structural nonuniformity and the discrete distribution of the adapters. Secondly, the transfer matrix method of a single beam is modified to solve the problem of discrete connection between the two beams of the double-beam model. Then the natural circular frequencies and mode shapes are calculated by the proposed method, comparing with the finite element method (FEM). Finally, the influence of the stiffness of radial vibration isolators and adapters on the dynamic characteristics of the system is analysed. The comparison shows that the results of the proposed method are well consistent with the FEM calculations and the proposed method is validated. The variations of the first six natural circular frequencies with radial vibration isolator stiffness and adapter stiffness are obtained, which provides a basis for the seismic-relieving design.


2012 ◽  
Vol 190-191 ◽  
pp. 1290-1294
Author(s):  
Feng Chen ◽  
Wei Zhang

The integrated transfer matrix method is brought forward on the basis of transfer matrix method and integrated transfer matrix theory is applied to the analysis on the dynamic characteristics of the main shaft for TM electronic jacquard machine. Through analysis on the dynamic model of the main shaft, the critical speed and the vibrating model of the main shaft for the high-speed electronic jacquard machine are derived theoretically and calculated and the first several order natural frequencies and the corresponding main vibration models of the main shaft are found. It is shown from the comparative analysis of the calculation results that the integrated transfer matrix method with higher computation accuracy can keep the characteristics of transfer matrix method such as simple programming, small computation amount and fast operation speed. This analysis and calculation method has higher reference value to the design of the main shaft of other types of jacquard machine and the dynamic analysis of similar complex rotor system.


Author(s):  
Cheng Meng ◽  
Ming Su ◽  
Shaobo Wang

This paper presents an investigation on dynamic characteristics of a rod-fastened rotor. Based on the framework of a traditional Riccati transfer matrix method (TMM), an improved Riccati TMM considering contact effects brought by a face tooth is developed. A correction coefficient for equivalent stiffness imported from a three-dimensional (3D) finite element contact case analysis is defined to evaluate the contact effects, and then the dynamic model of the rod-fastened rotor including bearing support is established. A computer program is further developed to obtain the dynamic characteristics such as critical speeds of lateral vibration, mode shapes, and an unbalance response. The improved TMM is applied to investigate the dynamic characteristics of a real central tie rod rotor of the class-F gas turbine for verification of its effectiveness, and the calculated critical speeds are in good agreement with test measurement results, implying that the method is accurate and the dynamic model is reliable. This approach can also be applied to analyze other combined rotors with a homogeneous structure.


2012 ◽  
Vol 538-541 ◽  
pp. 2477-2480
Author(s):  
Ming De Duan ◽  
Bo Yin Li ◽  
Guo Li Liang ◽  
Wu Guo Zhang ◽  
Xiao Feng Wang

Based on transfer matrix method, the dynamic model is established for the spindle system of a composite grinder, and the modal analysis is carried out. The lower-order modal shape and natural frequency in the determined condition is obtained, and the effects of the support span and the support stiffness on the dynamic characteristics of the spindle system are analyzed. The spindle system’s structure is parameterized by the use of Matlab to improve the efficiency of the modeling and calculation.


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