HYDROSTATIC AND ACTIVE CONTROL MOVABLE PAD BEARING

摘要

A one piece hydrodynamic bearing which can include hydrostatic support features. The pads are supported on a single thin web for pivoting on a support structure which can include one or more beam-like members. The bearings may have hydrostatic and active control attributes and is very attractive in cryogenic applications where it is very difficult to prevent leakage in conventional hydrostatic tilt pad bearings. The hydrostatic feed through the post eliminates this problem completely and prevents the fretting at the pivots common with conventional tilt pad bearings. A cavity provided under a pad support membrane can be used as an active control device. The pressure can cause the bearing set or assembly clearance to be reduced thus providing better damping and centering capability. The preload in the pad can be actively controlled in this manner. The pad has a limiting device to prevent a negative pre-load condition from occurring. This active control of bearing clearance can allow bearings to operate at large spreads in temperatures.