Combination bearing for gas turbine engine
AssigneeAllison Engine Company, Inc.
InventorsMark S. Henry, Victor Iannello, Eugene E. Pfaffenberger, Donald W. Burns
Life of this patent
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Abstract
The present invention contemplates a combination bearing for supporting a rotating rotor within a gas turbine engine. The combination bearing including a magnetic bearing system and dry solid lubricated rolling element auxiliary bearings units for sharing the shaft load. The rotating central shaft being normally supported by the active electromagnetic bearing system. The auxiliary bearing unit being soft mounted to the shaft and engine housing and rotatable with the shaft. Soft mounting of the bearings between the housing and the shaft allows a substantially stable transition from the all magnetic bearing support to a physically contacting mechanically assisted support of the shaft.
Claims29
A combination, comprising:
- a gas turbine engine having a mechanical housing;
- a shaft rotatable within said housing and having a plurality of airfoils coupled thereto;
- a magnetic bearing for supporting the shaft;
- and
- a rolling element bearing coupled to said shaft for sharing the load on said shaft said rolling element bearing having an inner race coupled to said shaft and an outer race coupled to said mechanical housing and a plurality of rolling elements normally contacting said inner race.
A combination, comprising:
- a gas turbine engine having a mechanical housing;
- a shaft rotatable within said housing and having a plurality of airfoils coupled thereto;
- an active radial magnetic bearing for normally supporting said shaft in a first condition;
- and
- an auxiliary bearing unit coupled to said shaft for sharing the load on said shaft in a second condition, said auxiliary bearing unit comprises:
- an auxiliary bearing having a first inner race and a first outer race and a plurality of first rolling elements normally contacting said first races;
- a first compliant interface coupling said first outer race to said housing;
- a second compliant interface coupling said first inner race to said shaft;
- a second rolling element bearing having a second inner race and a second outer race and a plurality of second rolling elements normally contacting said second races;
- a third compliant interface coupling said second outer race to said housing;
- and
- a fourth compliant interface coupling said second inner race to said shaft.
A combination, comprising:
- a gas turbine engine including a mechanical housing;
- a shaft rotatable within said housing and having a plurality of airfoils coupled thereto;
- a pair of spaced active electromagnetic radial bearings for normally supporting said shaft;
- a first auxiliary rolling element bearing unit coupled between said housing and said shaft for sharing the load on said shaft, said first auxiliary rolling element bearing unit disposed proximate one of said pair of spaced active electromagnetic radial bearings, said first auxiliary rolling element bearing unit having at least one first rolling element bearing with a first inner race coupled to said shaft and a first outer race coupled to said mechanical housing and at least one first rolling element normally contacting said first races;
- and
- a second auxiliary rolling element bearing unit coupled between said housing and said shaft for sharing the load on said shaft, said second auxiliary rolling element bearing unit disposed proximate the other of said pair of spaced active electromagnetic radial bearings, said second auxiliary rolling element bearing unit having at least one second rolling element bearing with a second inner race coupled to said shaft and a second outer race coupled to said mechanical housing and at least one second rolling element normally contacting said second races.
Dependencies are inferred from the claim text.