Experimental study on the lubrication characteristics of porous journal bearings with hydrodynamic shape forming at annular surface under sine-wave vibrated conditions (Examination into the shaft whirling behavior at pivot supported condition by measuring the time history waveform on shaft with parameter of vibrated Frequency changes)

Abstract

This report describes the study on the lubrication characteristics of porous journal bearings as a DC spindle motor's bearing system made with oil impregnated sintered materials having some hydrodynamic shapes. Herring Bone (I & II), Three Lobed Type or Sleeve as radial hydrodynamic shapes were proposed, and four kinds of specimens were produced for porous journal bearings with pivot supported conditions. They were examined experimentally to optimize the hydrodynamic shape of porous journal bearings by measuring the lubrication characteristics at the shaft starting state under sine-wave vibrated conditions. This report particularly refers to the experimental examination for Settling Time, Lissajous Curve Diagram or Shaft Whirling by measuring the Time History Waveform (T.H.W.) of the shaft such as the above mentioned lubrication characteristics under the same conditions. Furthermore, it was investigated to discuss the influences of vibrated frequency changes to the lubrication characteristics by measuring the T.H.W. of the shaft under the above conditions.