Oil scavenge system

Claim 2

In a gas turbine engine having a case assembly defining a main axis of said engine, a main shaft, a bearing assembly between said case assembly and said main shaft supporting said main shaft on said case assembly for rotation about said main axis, and oil supply means operative to direct a cooling and lubricating flow of oil to said bearing assembly, an oil scavenge system comprising: means on said case assembly defining a sump having one end exposed to said bearing assembly, means on said sump defining an inner surface around said main axis adjacent said bearing assembly, means on said bearing assembly operative to pump oil therefrom onto said inner surface with high tangential velocity so that said pumped oil centrifugally adheres to said inner surface and retains sufficient tangential velocity to form a centrifugally adhered annular pool of oil on said inner surface, means on said sump defining a drain entry in said inner surface at the bottom of said annular oil pool thereon so that said oil drains from said annular pool into said drain entry, and scavenge pump means on said engine connected directly to said drain entry and operative to exhaust from said sump all oil draining from said annular pool into said drain entry.

Claim 3

In a gas turbine engine having a case assembly defining a main axis of said engine, a main shaft, a bearing assembly between said case assembly and said main shaft supporting said main shaft on said case assembly for rotation about said main axis, and oil supply means operative to direct a cooling and lubricating flow of oil to said bearing assembly, an oil scavenge system comprising: means on said case assembly defining a sump having one end exposed to said bearing assembly, means on said sump defining a frustoconical inner surface around said main axis having a small diameter end adjacent said bearing assembly and a large diameter end space axia11y along said main axis from said small diameter end, means on said sump defining a constant diameter cylindrical inner surface around said main axis contiguous with said large diameter end of said frustoconical inner surface, the diameter of said cylindrical inner surface being equal to the diameter of said large diameter end of said frustoconical inner surface, means on said bearing assembly operative to pump oil therefrom onto said frustoconical inner surface generally at said small diameter end with high tangential velocity so that said pumped oil centrifugally adheres to said frustoconical inner surface and migrates therealong axially toward said large diameter end and said constant diameter inner surface, said oil flowing from said frustoconical inner surface onto said constant diameter inner surface and retaining sufficient tangential velocity to centrifugally adhere to said constant diameter inner surface so that said oil forms an annular pool on said constant diameter inner surface, means on said sump defining a drain entry in said constant diameter inner surface at the bottom of said annular oil pool thereon so that said oil drains from said annular pool into said drain entry, and scavenge pump means on said engine connected directly to said drain entry and operative to exhaust from said sump all oil draining from said annular pool into said drain entry.

Claim 4

In a gas turbine engine having a case assembly defining a main axis of said engine, a main shaft, a bearing assembly between said case assembly and said main shaft supporting said main shaft on said case assembly for rotation about said main axis, and oil supply means operative to direct a cooling and lubricating flow of oil to said bearing assembly, an oil scavenge system comprising: means on said case assembly defining a sump having one end exposed to said bearing assembly, means on said sump defining a frustoconical inner surface around said main axis having a small diameter end adjacent said bearing assembly and a large diameter end space axia11y along said main axis from said small diameter end, means on said sump defining a constant diameter cylindrical inner surface around said main axis contiguous with said large diameter end of said frustoconical inner surface, the diameter of said cylindrical inner surface being equal to the diameter of said large diameter end of said frustoconical inner surface, means on said bearing assembly operative to pump oil therefrom onto said frustoconical inner surface generally at said small diameter end with high tangential velocity so that said pumped oil centrifugally adheres to said frustoconical inner surface and migrates therealong axially toward said large diameter end and said constant diameter inner surface, said oil flowing from said frustoconical inner surface onto said constant diameter inner surface and retaining sufficient tangential velocity to centrifugally adhere to said constant diameter inner surface so that said oil forms an annular pool on said constant diameter inner surface, means on said sump defining a drain entry in said constant diameter inner surface at the bottom of said annular oil pool thereon so that said oil drains from said annular pool into said drain entry, and scavenge pump means on said engine connected directly to said drain entry and operative to exhaust from said sump all oil draining from said annular pool into said drain entry.

Claim 5

In a gas turbine engine having a case assembly defining a main axis of said engine and an annular gas flow path around said main axis, a main shaft, means on said case assembly defining a pedestal mount around said main axis radially inboard of said gas flow path, a pair of bearing assemblies between said main shaft and said pedestal mount rotatably supporting said main shaft on said pedestal mount at axially spaced locations along said main axis for rotation about said main axis, and oil supply means operative to direct a cooling and lubricating flow of oil to each of said bearing assemblies, an oil scavenge system comprising: means on said pedestal mount defining a first frustoconical inner surface around said main axis having a small diameter end adjacent one of said bearing assemblies and a large diameter end space axially along said main axis from said small diameter end, means on said pedestal mount defining a second frustoconical inner surface around said main axis having a small diameter end adjacent the other of said bearing assemblies and a large diameter end space axially along said main axis from said small diameter end, means on said pedestal mount defining a constant diameter cylindrical inner surface around said main axis between said first and said second frustoconical inner surfaces and contiguous with said large diameter ends of each of said first and said second frustoconical inner surfaces, the diameter of said cylindrical inner surface being equal to the diameters of each of said large diameter ends of said first and said second frustoconical inner surfaces, means on each of said one and said other bearing assemblies operative to pump oil therefrom onto the corresponding one of said first and said second frustoconical inner surfaces generally at said small diameter ends thereof with high tangential velocity so that said pumped oil centrifugally adheres to said first and said second frustoconical inner surfaces and migrates therealong axially toward said large diameter ends and said constant diameter inner surface, said oil flowing from said first and said second frustoconical inner surfaces onto said constant diameter inner surface and retaining sufficient tangential velocity to centrifugally adhere to said constant diameter inner surface so that said oil forms an annular pool on said constant diameter inner surface, means defining a drain entry in said constant diameter inner surface at the bottom of said annular oil pool thereon so that said oil drains from said annular pool into said drain entry, and scavenge pump means on said engine connected directly to said drain entry and operative to exhaust all oil draining from said annular pool into said drain entry.

Claim 6

In a gas turbine engine having a case assembly defining a main axis of said engine and an annular gas flow path around said main axis, a main shaft, means on said case assembly defining a pedestal mount around said main axis radially inboard of said gas flow path, a pair of bearing assemblies between said main shaft and said pedestal mount rotatably supporting said main shaft on said pedestal mount at axially spaced locations along said main axis for rotation about said main axis, and oil supply means operative to direct a cooling and lubricating flow of oil to each of said bearing assemblies, an oil scavenge system comprising: means on said pedestal mount defining a first frustoconical inner surface around said main axis having a small diameter end adjacent one of said bearing assemblies and a large diameter end space axially along said main axis from said small diameter end, means on said pedestal mount defining a second frustoconical inner surface around said main axis having a small diameter end adjacent the other of said bearing assemblies and a large diameter end space axially along said main axis from said small diameter end, means on said pedestal mount defining a constant diameter cylindrical inner surface around said main axis between said first and said second frustoconical inner surfaces and contiguous with said large diameter ends of each of said first and said second frustoconical inner surfaces, the diameter of said cylindrical inner surface being equal to the diameters of each of said large diameter ends of said first and said second frustoconical inner surfaces, means on each of said one and said other bearing assemblies operative to pump oil therefrom onto the corresponding one of said first and said second frustoconical inner surfaces generally at said small diameter ends thereof with high tangential velocity so that said pumped oil centrifugally adheres to said first and said second frustoconical inner surfaces and migrates therealong axially toward said large diameter ends and said constant diameter inner surface, said oil flowing from said first and said second frustoconical inner surfaces onto said constant diameter inner surface and retaining sufficient tangential velocity to centrifugally adhere to said constant diameter inner surface so that said oil forms an annular pool on said constant diameter inner surface, means defining a drain entry in said constant diameter inner surface at the bottom of said annular oil pool thereon so that said oil drains from said annular pool into said drain entry, and scavenge pump means on said engine connected directly to said drain entry and operative to exhaust all oil draining from said annular pool into said drain entry.

Claim 7

The oil scavenge system recited in claim 3 wherein said means on each of said one and said other bearing assemblies operative to pump oil therefrom onto respective ones of said first and said second frustoconical inner surfaces includes a flat impeller around said main axis having an inner surface radially inboard of and axially overlapping said small diameter end of the corresponding one of said first and said second frustoconical inner surfaces, said flat impeller inner surface tapering radially out in the axial direction proceeding from the corresponding end of said sump toward the center thereof, a hub section attached to said main shaft for rotation as a unit therewith, a circumferential array of radially extending spokes between said hub section and said flat impeller operative to connect said flat impeller to said hub section so that said flat impeller rotates at the speed of said main shaft, and means on said bearing assembly operative to channel said cooling and lubricating flow of oil after cooling and lubrication onto said impeller inner surface.

Claim 8

In a gas turbine engine having a case assembly defining a main axis of said engine, a main shaft, a bearing assembly between said case assembly and said main shaft supporting said main shaft on said case assembly for rotation about said main axis, and oil supply means operative to direct a cooling and lubricating flow of oil to said bearing assembly, a method of scavenging oil from said bearing assembly comprising: forming on said case assembly a sump having one end exposed to said bearing assembly, forming on said sump an inner surface around said main axis adjacent said bearing assembly, forming on said bearing assembly pumping means operative to pump oil therefrom onto said inner surface with high tangential velocity so that said pumped oil centrifugally adheres to said inner surface and retains sufficient tangential velocity to form a centrifugally adhered annular pool of oil on said inner surface, forming on said sump inner surface a drain entry at the bottom of said annular oil pool thereon so that said oil drains from said annular pool into said drain entry, and directly scavenging from said drain entry all oil draining from said annular pool into said drain entry.

Claim 9

In a gas turbine engine having a case assembly defining a main axis of said engine, a main shaft, a bearing assembly between said case assembly and said main shaft supporting said main shaft on said case assembly for rotation about said main axis, and oil supply means operative to direct a cooling and lubricating flow of oil to said bearing assembly, a method of scavenging oil from said bearing assembly comprising: forming on said case assembly a sump having one end exposed to said bearing assembly, forming on said sump an inner surface around said main axis adjacent said bearing assembly, forming on said bearing assembly pumping means operative to pump oil therefrom onto said inner surface with high tangential velocity so that said pumped oil centrifugally adheres to said inner surface and retains sufficient tangential velocity to form a centrifugally adhered annular pool of oil on said inner surface, forming on said sump inner surface a drain entry at the bottom of said annular oil pool thereon so that said oil drains from said annular pool into said drain entry, and directly scavenging from said drain entry all oil draining from said annular pool into said drain entry.

Claim 10

In a gas turbine engine having a case assembly defining a main axis of said engine, a main shaft, a bearing assembly between said case assembly and said main shaft supporting said main shaft on said case assembly for rotation about said main axis, and oil supply means operative to direct a cooling and lubricating flow of oil to said bearing assembly, a method of scavenging oil from said bearing assembly comprising: forming on said case assembly a sump having one end exposed to said bearing assembly, forming on said sump a frustoconical inner surface around said main axis having a small diameter end adjacent said bearing assembly and a large diameter end space axially along said main axis from said small diameter end, forming on said sump a constant diameter cylindrical inner surface around said main axis contiguous with said large diameter end of said frustoconical inner surface having a diameter equal to the diameter of said large diameter end of said frustoconical inner surface, forming on said bearing assembly pumping means operative to pump oil from said bearing assembly onto said frustoconical inner surface generally at said small diameter end with sufficient tangential velocity to centrifugally adhere said pumped oil to said frustoconical inner surface as it migrates therealong axially toward said large diameter end and to centrifugally adhere said pumped oil to said constant diameter inner surface so that said pumped oil forms an annular pool on said constant diameter inner surface, forming a drain entry in said constant diameter inner surface of said sump at the bottom of said annular oil pool thereon so that said oil drains from said annular pool into said drain entry, and directly scavenging said oil from said drain entry.

Claim 11

In a gas turbine engine having a case assembly defining a main axis of said engine, a main shaft, a bearing assembly between said case assembly and said main shaft supporting said main shaft on said case assembly for rotation about said main axis, and oil supply means operative to direct a cooling and lubricating flow of oil to said bearing assembly, a method of scavenging oil from said bearing assembly comprising: forming on said case assembly a sump having one end exposed to said bearing assembly, forming on said sump a frustoconical inner surface around said main axis having a small diameter end adjacent said bearing assembly and a large diameter end space axially along said main axis from said small diameter end, forming on said sump a constant diameter cylindrical inner surface around said main axis contiguous with said large diameter end of said frustoconical inner surface having a diameter equal to the diameter of said large diameter end of said frustoconical inner surface, forming on said bearing assembly pumping means operative to pump oil from said bearing assembly onto said frustoconical inner surface generally at said small diameter end with sufficient tangential velocity to centrifugally adhere said pumped oil to said frustoconical inner surface as it migrates therealong axially toward said large diameter end and to centrifugally adhere said pumped oil to said constant diameter inner surface so that said pumped oil forms an annular pool on said constant diameter inner surface, forming a drain entry in said constant diameter inner surface of said sump at the bottom of said annular oil pool thereon so that said oil drains from said annular pool into said drain entry, and directly scavenging said oil from said drain entry.