Numerical Simulation of a Slipper Model for Swash Plate Type Axial Piston Pumps and Motors: Effects of Concave and Convex Surface Geometry
Toshiharu Kazama and Yukihito Narita
College of Design and Manufacturing Technology, Graduate School of Engineering, Muroran Institute of Technology, 27-1 Mizumoto-cho, Muroran, Hokkaido 050-8585, Japan
In this study, the slipper of swash plate axial piston pumps and motors is modeled as a hybrid (hydrostatic and hydrodynamic) thrust pad bearing. The effects of the slightly concave and convex geometries of the slipper sliding surface are examined. The motion of the slipper model is numerically simulated, and its tribological characteristics are examined under eccentric and dynamic load conditions. The calculations under these conditions indicate that, for the concave slipper, the fluctuation of the bearing pad azimuth increases, and the attitude of the slipper becomes unstable. In contrast, for the convex slipper, the attitude becomes stable, but the clearance increases.
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