【摘 要】
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This study presents a method for measuring the imbalance in a small-sized cylindrical roller.The roller imbalance was calibrated on the built static-pressure-air flotation measurement machine.The impact of the roller imbalance on the dynamic characteristi
【机 构】
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School of Information Engineering,Henan University of Science and Technology,Luoyang 471003,China;Po
论文部分内容阅读
This study presents a method for measuring the imbalance in a small-sized cylindrical roller.The roller imbalance was calibrated on the built static-pressure-air flotation measurement machine.The impact of the roller imbalance on the dynamic characteristics of a cage were then studied on the aero-bearing test rig.The displacement spectrums with different roller imbalance of the obtained cage orbits under various bearing speed and radial load were used to evaluate the cage stability.The results show that the cage cannot form a stable operating state at a lower bearing speed with or without the unbalanced rollers.The cage with balanced rollers gradually develops stable motion with the increase of the bearing speed.The existence of a small roller imbal-ance causes the stability of the cage to deteriorate.With an increase in the bearing speed and radial load,the cage with the unbalanced rollers runs unsteadily accompanied by a high-frequency vibra-tion when the roller imbalance is large enough.The vibration amplitude of the cage in the horizon-tal direction is greater than that in the vertical direction during an unstable operation,which is similar in the stable status.
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