Under race bearing lubrication system for gas turbine engines

Abstract

A bearing lubrication system for a gas turbine engine that has bearings supporting a rotor shaft comprises a housing for the engine that serves as a primary static structural support; a rotor shaft for mounting rotational components of the engine; at least two bearings for supporting the rotor shaft within the housing, each bearing comprising an inner race that couples to the rotor shaft comprising a plurality of inner race lubricant apertures that extend radially through the inner race that supply pressurised lubricant to selected regions within the bearing, an outer race that couples to a primary static structural support, a plurality of ball elements between the inner race and the outer race and a ball cage to maintain the relative radial spacing of the ball elements between each other within the inner race and the outer race; and a lubricant distribution system for delivering pressurised lubricant to the inner race apertures in each of the bearings.

1 . A ball bearing assembly for supporting a rotor shaft in a gas turbine engine, comprising:
 an inner race that couples to the rotor shaft comprising a plurality of inner race lubricant apertures that extend radially through the inner race that supply pressurised lubricant to selected regions within the bearing;   an outer race that couples to a primary static structural support;   a plurality of ball elements between the inner race and the outer race; and   a ball cage to maintain the relative radial spacing of the ball elements between each other within the inner race and the outer race.   
   
   
       2 . The ball bearing assembly of  claim 1 , wherein the inner race lubricant apertures form at least one radial row around the inner race. 
   
   
       3 . The ball bearing assembly of  claim 2 , wherein the inner race lubricant apertures form two radial rows around the inner race. 
   
   
       4 . A bearing lubrication system for a gas turbine engine that has bearings supporting a rotor shaft, comprising:
 a housing for the engine that serves as a primary static structural support;   a rotor shaft for mounting rotational components of the engine;   at least two bearings for supporting the rotor shaft within the housing, each bearing comprising an inner race that couples to the rotor shaft comprising a plurality of inner race lubricant apertures that extend radially through the inner race that supply pressurised lubricant to selected regions within the bearing, an outer race that couples to a primary static structural support, a plurality of ball elements between the inner race and the outer race and a ball cage to maintain the relative radial spacing of the ball elements between each other within the inner race and the outer race; and   a lubricant distribution system for delivering pressurised lubricant to the inner race apertures in each of the bearings.   
   
   
       5 . The bearing lubrication system of  claim 4 , wherein the lubricant comprises fuel for the engine. 
   
   
       6 . The bearing lubrication system of  claim 4 , wherein the lubricant comprises oil. 
   
   
       7 . The bearing lubrication system of  claim 4 , wherein the lubricant comprises a mixture of fuel for the engine and oil. 
   
   
       8 . The bearing lubrication system of  claim 4 , wherein the lubricant distribution system comprises a lubricant source that supplies the lubricant. 
   
   
       9 . The bearing lubrication system of  claim 8 , wherein the lubricant distribution system further comprises a lubricant pump for pressurising the lubricant. 
   
   
       10 . The bearing lubrication system of  claim 9 , wherein the lubricant distribution system further comprises a pressurised lubricant galley for supplying lubricant to a forward one of the bearings. 
   
   
       11 . The bearing lubrication system of  claim 9 , wherein the lubricant distribution system further comprises a pressurised rotor shaft lubricant channel for supplying lubricant to at least one aft bearing. 
   
   
       12 . The bearing lubrication system of  claim 4 , wherein airflow through the engine propagates lubricant from a forward one of the bearings to at least one aft bearing and into a combustion chamber for the engine. 
   
   
       13 . A gas turbine engine comprising:
 a housing for the engine that serves as a primary static structural support;   a rotor shaft;   a compressor wheel mounted on the rotor shaft for compressing air;   a combustion chamber for combusting the compressed air with fuel to generate expanding exhaust gas;   a turbine wheel mounted on the rotor shaft driven by the expanding exhaust gas;   at least two bearings for supporting the rotor shaft within the housing, each bearing comprising an inner race that couples to the rotor shaft comprising a plurality of inner race lubricant apertures that extend radially through the inner race that supply pressurised lubricant to selected regions within the bearing, an outer race that couples to a primary static structural support, a plurality of ball elements between the inner race and the outer race and a ball cage to maintain the relative radial spacing of the ball elements between each other within the inner race and the outer race; and   a lubricant distribution system for delivering pressurised lubricant to the inner race apertures in each of the bearings.   
   
   
       14 . The engine of  claim 13 , wherein the lubricant comprises fuel for the engine. 
   
   
       15 . The bearing lubrication system of  claim 13 , wherein the lubricant comprises oil. 
   
   
       16 . The engine of  claim 13 , wherein the lubricant comprises a mixture of fuel for the engine and oil. 
   
   
       17 . The engine of  claim 13 , wherein the lubricant distribution system comprises a lubricant source that supplies the lubricant. 
   
   
       18 . The engine of  claim 17 , wherein the lubricant distribution system further comprises a lubricant pump for pressurising the lubricant. 
   
   
       19 . The engine of  claim 18 , wherein the lubricant distribution system further comprises a pressurised lubricant galley for supplying lubricant to a forward one of the bearings. 
   
   
       20 . The engine of  claim 18 , wherein the lubricant distribution system further comprises a pressurised rotor shaft lubricant channel for supplying lubricant to at least one aft bearing. 
   
   
       21 . The bearing lubrication system of  claim 13 , wherein airflow through the engine propagates lubricant from a forward one of the bearings to at least one aft bearing and into a combustion chamber for the engine.