Patent ID: 7371011
Filing Date: 2008-05-13
Classification: F01D,F05D,F16C

Abstract:
1. A shaft bearing system for use in a turbomachine having a turbine wheel and a compressor impeller carried on a common shaft extending through a turbomachine center housing, said shaft bearing system comprising: an axially split bearing carrier including a pair of generally cylindrical bearing sleeves mounted within the center housing; a pair of angular contact ball bearing units each having a complement of bearing balls carried between an inner race ring and an outer race ring, said bearing units being mounted on the shaft and mounted respectively within said bearing sleeves whereby said bearing units rotatably support the shaft relative to said bearing sleeves; said bearing units being configured to carry thrust loads acting in an axially inboard direction relative to the center housing; thrust pre-load means comprising a spring member for applying an axially outboard-directed thrust pre-load of predetermined force to said bearing sleeves, said thrust pre-load being transmitted by said bearing sleeves to the associated bearing units mounted therein; and hydraulic means for supplementing said thrust pre-load applied by said spring member; said split bearing carrier cooperating with said bearing units to define an elongated chamber surrounding the shaft axially between said bearing units, said hydraulic means including at least one flow port for circulating a hydraulic fluid into said chamber; said at least one flow port being defined cooperatively by slidably interfitted inboard end segments of said bearing sleeves, and at least one oil feed hole formed within one of said bearing sleeves.