Research on lubrication model and dynamics performance control of the hybrid bearing with single tilting pad

In order to realize high rigidity and adjustable performance of spindle bearing of precision machine tool, a single tilting pad hybrid bearing is proposed, which can replace one oil chamber of the common hydrostatic bearing with tilting pad, and the load is carried by the dynamic pressure of the tilting pad and the static pressure of other oil cavities. The lubrication model of the new dynamic and static bearing is established. The calculation method of bearing balance point is proposed. The bearing performance under different working conditions is calculated, including stiffness and minimum film thickness. On this basis, the regulation law of preload coefficient and pivot coefficient on bearing performance is analyzed. Through the regulation of the tilting fulcrum, when the pivot coefficient is 0.75 and the preloading coefficient is 0.5, the bearing stiffness can reach 2 700 N/μm, which meets the high stiffness requirements of the spindle system of machine tool.