Journal of Mechanical Science and Technology

The Korean Society of Mechanical Engineers (대한기계학회)
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Measurement of Fluid Film Thickness on the Valve Plate in Oil Hydraulic Axial Piston rumps (I) - Bearing Pad Effects -

  • Kim, Jong-Ki (Graduate School of Precision Mechanical Engineering, Chonbuk National University) ;
  • Jung, Jae-Youn (School of Mechanical and Aerospace System Engineering, Chonbuk National University)
  • Published : 2003.02.01
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Abstract

The tribological mechanism between the valve plate and the cylinder block in oil hydraulic axial piston pumps plays an important role on high power density. In this study, the fluid film thickness between the valve plate and the cylinder block was measured with discharge pressure and rotational speed by use of a gap sensor, and a slip ring system in the operating period. To investigate the effect of the valve plate shapes, we designed two valve plates with different shapes . the first valve plate was without a bearing pad, while the second valve plate had a bearing pad. It was found that both valve plates behaved differently with respect to the fluid film thickness characteristics. The leakage flow rates and the shaft torque were also experimented in order to clarify the performance difference between the valve plate without a bearing pad and the valve plate with a bearing pad. From the results of this study, we found out that in the oil hydraulic axial piston pumps, the valve plate with a bearing pad showed better film thickness contours than the valve plate without a bearing pad.

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References

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