Zhang K.-Z.,Shanghai Key Laboratory of Digital Autobody Engineering |
Yu H.-D.,Shanghai Key Laboratory of Digital Autobody Engineering |
Yu H.-D.,Xi'an Jiaotong University |
Zeng X.-X.,Shanghai Key Laboratory of Digital Autobody Engineering |
And 3 more authors.
Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science | Year: 2011
Multiple pinion drives, parallel arrangements of the pinions for large torque transmission, are widely utilized in various heavy-duty industrial applications. For such multi-mesh gear systems, periodic mesh stiffnesses could possibly cause parametric instabilities and server vibrations. Basedonthe Floquet-Lyapunov theory, numerical simulations are conducted to determine the parametric instability status. For rectangular waveforms assumption of the mesh stiffness variations, the primary, secondary, and combination instabilities of the multiple pinion drives are studied. The effects of mesh stiffness parameters, including mesh frequencies, stiffness variation amplitudes, and mesh phasing, on these instabilities are yielded. Unstable regions are also indicated for different gear pair configurations. Instability conditions of three-pinion drives are obtained and compared with those of the three-stage gear train. © Authors 2011.
Chu G.,Shanghai Key Laboratory of Digital Autobody Engineering |
Wei C.,SAIC |
Zou J.,Shanghai Key Laboratory of Digital Autobody Engineering |
Qiche Gongcheng/Automotive Engineering | Year: 2014
In view of the features of vehicle body measured data, i.e. small sample and non-normal distribution in certain time or of certain type, a distance-based multi-outliers sorting/detection algorithm for vehicle body measurement is proposed, and a judgment criterion is derived for distinguishing the outliers caused by sudden changes in production process from the outliers caused by gross error of measurement. The method is validated with a real example of gap and flush measurement of a vehicle.
Shen Q.,Shanghai Key Laboratory of Digital Autobody Engineering |
Li Y.B.,Shanghai Key Laboratory of Digital Autobody Engineering |
Lin Z.Q.,Shanghai Key Laboratory of Digital Autobody Engineering |
Chen G.L.,Shanghai Key Laboratory of Digital Autobody Engineering
IEEE Transactions on Magnetics | Year: 2011
The applications of magnetic field in metal casting and welding processes have drawn much attention of researchers. However, the effect of external magnetic field on nugget formation of resistance spot welding (RSW) is still lack of understanding. In this paper, the effect of a radially oriented constant magnetic field generated by a pair of ring-shaped permanent magnets on the weld nugget of RSW was experimentally investigated. The nugget diameter, microhardness, and mechanical performance were compared between welds with and without the external magnetic field. Results showed that, under the action of the external magnetic field, the weld nugget got wider with an increase in diameter by nearly 10%. Besides, the Vickers hardness in fusion zone (FZ) of the welding joint was more uniform. As a result, the RSW joints welded under the constant magnetic field exhibited better mechanical performance in tensile-shear tests. Therefore, the application of the external constant magnetic field could be an effective way to control the weld quality of RSW by affecting its melting and crystallization process. © 2011 IEEE.