共查询到19条相似文献,搜索用时 281 毫秒
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Bo-Suk Yang Soo-Jong Lee Tian Han 《Journal of Mechanical Science and Technology》2006,20(12):2013-2024
This paper proposes a condition classification system using wavelet transform, feature evaluation and artificial neural networks
to detect faulty products on the production line of reciprocating compressors for refrigerators. The stationary features of
vibration signals are extracted from statistical cumulants of the discrete wavelet coefficients and root mean square values
of band-pass frequencies. The neural networks are trained by the sample data, including healthy or faulty compressors. Based
on training, the proposed system can be used on the automatic mass production line to classify product quality instead of
people inspection. The validity of this system is demonstrated by the on-site test at LG Electronics, Inc. for reciprocating
compressors. According to different products, this system after some modification may be useful to increase productivity in
different types of production lines. 相似文献
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低温冷库作为耗能大户,一直受到人们的关注,如何实现节能,关系到冷库行业的发展.本文分别从理论和工程实例探讨在低温冷库中压缩机的节能选型,针对低温冷库不同情况分别给出了选型建议,为设计单位和使用单位在选取低温冷库压缩机时提供了依据. 相似文献
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介绍了传统旋转电机驱动压缩机和改进后直线电机驱动压缩机的结构形式、工作原理及性能,指出直线压缩机的显著优势和可观的发展前景。 相似文献
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An experimental study on oil-film dynamic coefficients 总被引:1,自引:1,他引:0
The oil-film force of hydrodynamic bearing is often characterized by a set of linear stiffness and damping coefficients. This paper presents an experimental method to recognize these coefficients and establishes their characteristics under varieties of operating conditions. The fundamental test model is obtained from a Taylor series expansion of bearing reaction force. A delicate test rig is constructed and experimental data are acquired under various testing conditions. The coefficients are evaluated by means of least mean square in time domain. The experiments indicate that the linear oil-film dynamic coefficients are sensitive to the excitation force. The sensitivity is varied for the different coefficients. From the investigation, it can be seen that the linear model is invalid under condition of high excitation force. That is to say, the nonlinear components, which are ignored in traditional linear model, should be considered in those conditions. 相似文献
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WeiZhouhong SchinstockDaleE 《机械工程学报(英文版)》2005,18(1):5-9
Three feedforward (FFD) control techniques for position-servo machine axes are compared. All three FFD controllers are used with two different PID feedback (FBK) controllers. The two different FBK controllers have two different closed-loop bandwidths. They are demonstrated using experimental data from a linear motor test system and from simulations. Laboratory results using the linear motor hardware demonstrate that the velocity & acceleration (V&A) FFD controller improves tracking in all case considered, while the other two FFD controllers actually degrade performance in many cases. Through simulation this degradation is attributed to extreme sensitivity to round off errors. This sensitivity is the result of a complex controller that is implemented outside of the feedback loop. 相似文献