Abstract
Reasonable design methods of the optimum dimensions of the bearing/seal parts of hydraulic equipment are presented. The minimum power loss, minimum dimensions (maximum load carrying capacity), and maximum moment-stiffness, as well as the maximum stiffness, are established as the optimum conditions. In this study, we have used circular hydrostatic bearings as the bearing/seal parts. The basic equations considering the effects of the dynamic supply pressure, eccentric dynamic load, and elastic deformation are derived. The representative design parameters are the radius of the bearing/seal parts, pocket radius ratio, and aspect ratio of the restrictor. In this report, we discuss the optimum analytical solutions for the hydrostatic thrust bearings with the capillary restrictor under steady concentric loads. The conditions of the minimum power loss, maximum load carrying capacity, and maximum stiffness correspond to that the ratio of power losses of leakage to friction is 1/3, the pocket radius is equal to the equivalent radius of load-area, and the pocket pressure ratio is 2/3, respectively. The optimum design methods based on the minimum power loss and minimum dimensions considering the degree of freedom of design are presented. From the maximum moment-stiffness, it shows that the optimum pocket pressure ratio is given by 5/6, and this is a favorable design method for a miniaturization of the bearing/seal parts.
