1. A dynamo electric machine for an aircraft gas turbine engine including a housing supporting a stator of the dynamo electric machine, a rotor assembly rotatably mounted in the housing and including an elongate hollow rotor shaft, a main shaft for connection at one end to the associated gas turbine engine assembly, said main shaft extending coaxially within said hollow rotor shaft, and, a sleeve-like member of electrically insulating material between said rotor shaft and said main shaft, said sleeve-like member providing an electrically insulating driving connection between said main shaft and said rotor shaft whereby said main shaft and said rotor shaft rotate together,
wherein a large diameter washer of an electrically insulating material is carried adjacent one end of the main shaft.
2. A machine according to claim 1, wherein the sleeve-like member has an outer surface of non-circular cross-sectional shape, the inner surface of the adjacent part of the rotor shaft being of substantially the same non-circular shape.
3. A machine according to claim 2, wherein the said non-circular cross-sectional shape is a square section.
4. A machine according to claim 3, wherein the corners of the square cross-section are rounded.
5. A machine according to claim 1, wherein the sleeve-like member has an inner surface of non-circular cross-sectional shape, the outer surface of the adjacent part of the main shaft being of substantially the same non-circular shape.
6. A machine according to claim 5, wherein the said non-circular cross-sectional shape is a square section.
7. A machine according to claim 6, wherein the corners of said square cross-section are rounded.
8. A machine according to claim 1, further comprising a spring loaded dampener assembly.
9. A machine according to claim 8, wherein ceramic layers are interposed between components of the spring loaded dampener assembly and the rotor and main shafts.
10. A dynamo electric machine for an aircraft gas turbine engine including a housing supporting a stator of the dynamo electric machine, a rotor assembly rotatably mounted in the housing and including an elongate hollow rotor shaft, a main shaft for connection at one end to the associated gas turbine engine assembly, said main shaft extending coaxially within said hollow rotor shaft, and, a sleeve-like member of electrically insulating material between said rotor shaft and said main shaft, said sleeve-like member providing an electrically insulating driving connection between said main shaft and said rotor shaft whereby said main shaft and said rotor shaft rotate together,
wherein the sleeve-like member has an outer surface of non-circular cross-sectional shape, the inner surface of the adjacent part of the rotor shaft being of substantially the same non-circular shape, and
wherein a large diameter washer of an electrically insulating material is carried adjacent one end of the main shaft.
11. A machine according to claim 10, wherein the said non-circular cross-sectional shape is a square section.
12. A machine according to claim 11, wherein the corners of the square cross-section are rounded.
13. A machine according to claim 10, wherein the sleeve-like member has an inner surface of non-circular cross-sectional shape, the outer surface of the adjacent part of the main shaft being of substantially the same non-circular shape.
14. A machine according to claim 13, wherein the said non-circular cross-sectional shape is a square section.
15. A machine according to claim 14, wherein the corners of said square cross-section are rounded.
16. A machine according to claim 10, further comprising a spring loaded dampener assembly.
17. A machine according to claim 16, wherein ceramic layers are interposed between components of the spring loaded dampener assembly and the rotor and main shafts.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An exhaust gas recirculation system in fluid communication with an intake system of an internal combustion engine comprising:
an exhaust system having an exhaust manifold in fluid communication with cylinders of the internal combustion engine and configured to remove exhaust therefrom;
an exhaust gas driven turbocharger having a turbine housing including a high pressure turbine inlet in fluid communication with the exhaust manifold and configured to receive exhaust gas therefrom, a low pressure turbine outlet in fluid communication with an exhaust gas conduit of the exhaust system for discharge of exhaust gas from the turbine housing and a compressor housing having a low pressure compressor inlet in communication with ambient and a high pressure compressor outlet in communication with the intake system;
an exhaust gas recirculation conduit in fluid communication with the exhaust gas conduit and configured to divert a portion of exhaust gas therefrom;
a low pressure exhaust gas recirculation branch extending between and fluidly connecting the exhaust gas recirculation conduit and the intake system to deliver uncompressed exhaust gas thereto; and
a high pressure exhaust gas recirculation branch extending between and fluidly connecting the exhaust gas recirculation conduit and the low pressure compressor inlet of the exhaust gas driven turbocharger and configured to deliver exhaust gas to the low pressure compressor inlet for compression in said exhaust gas driven turbocharger and delivery to the intake system.
2. The exhaust gas recirculation system of claim 1, further comprising:
a first exhaust gas recirculation valve disposed in the low pressure exhaust gas recirculation branch and configured to adjust a volumetric quantity of exhaust gas delivered to the intake system; and
a second exhaust gas recirculation valve disposed in the high pressure exhaust gas recirculation branch and configured to adjust a volumetric quantity of exhaust gas to be delivered to the compressor housing for compression therein and delivery to the intake system.
3. The exhaust gas recirculation system of claim 2, further comprising:
a controller in signal communication with the internal combustion engine and the first and second exhaust gas recirculation valves and configured to operate the valves to adjust the volumetric quantity of exhaust gas flowing therethrough.
4. The exhaust gas recirculation system of claim 1, further comprising:
an exhaust gas cooler in fluid communication with the high pressure exhaust gas recirculation branch.
5. The exhaust gas recirculation system of claim 1, further comprising:
an intake charge cooler in fluid communication with the intake system of the internal combustion engine.
6. The exhaust gas recirculation system of claim 1, further comprising:
an exhaust gas cooler in fluid communication with the exhaust gas recirculation conduit and located upstream of the low pressure exhaust gas recirculation branch and the high pressure exhaust gas recirculation branch.
7. The exhaust gas recirculation system of claim 6, further comprising:
an exhaust gas diverter branch in fluid communication with the exhaust gas recirculation conduit at a location upstream of the exhaust gas cooler and extending to, and in fluid communication with the low pressure exhaust gas recirculation branch; and
a bypass valve disposed in the exhaust gas diverter branch and configured to divert high temperature, un-cooled exhaust gas from the exhaust gas recirculation conduit and to the low pressure exhaust gas recirculation branch.
8. The exhaust gas recirculation system of claim 7, further comprising:
a controller in signal communication with the internal combustion engine and the bypass valve and configured to operate the valve to vary a temperature of exhaust gas flowing to the low pressure exhaust gas recirculation branch and the intake system of the internal combustion engine.
9. An internal combustion engine comprising:
an intake system having an intake manifold in fluid communication with cylinders of the internal combustion engine and configured to deliver an intake charge thereto;
a throttle in fluid communication with the intake manifold and configured to receive the intake air charge from an intake air conduit for delivery to the intake manifold;
an exhaust system having exhaust manifold in fluid communication with the cylinders of the internal combustion engine and configured to remove exhaust gas therefrom;
an exhaust gas driven turbocharger including a high pressure turbine inlet in fluid communication with the exhaust manifold, a low pressure turbine outlet in fluid communication with an exhaust gas conduit of the exhaust system and a compressor housing including a low pressure compressor inlet in communication with ambient and a high pressure compressor outlet in communication with the intake air conduit;
an exhaust gas recirculation conduit in fluid communication with the exhaust gas conduit;
a low pressure exhaust gas recirculation branch extending between the exhaust gas recirculation conduit and the intake system at a position downstream of the throttle; and
a high pressure exhaust gas recirculation branch extending between the exhaust gas recirculation conduit and the low pressure compressor inlet of the exhaust gas driven turbocharger.
10. The internal combustion engine of claim 9, further comprising:
a first exhaust gas recirculation valve disposed in the low pressure exhaust gas recirculation branch; and
a second exhaust gas recirculation valve disposed in the high pressure exhaust gas recirculation branch.
11. The internal combustion engine of claim 10, further comprising:
a controller in signal communication with the internal combustion engine and the first and second exhaust gas recirculation valves and configured to operate the valves to vary a volumetric quantity of exhaust gas flowing therethrough.
12. The internal combustion engine of claim 9, further comprising:
an exhaust gas cooler in fluid communication with the high pressure exhaust gas recirculation branch.
13. The internal combustion engine of claim 9, further comprising an intake charge cooler in fluid communication with the intake air conduit.
14. The internal combustion engine of claim 9, further comprising:
an exhaust gas cooler in fluid communication with the exhaust gas recirculation conduit and located upstream of the low pressure exhaust gas recirculation branch and the high pressure exhaust gas recirculation branch.
15. The internal combustion engine of claim 14, further comprising:
an exhaust gas diverter branch in fluid communication with the exhaust gas recirculation conduit at a location upstream of the exhaust gas cooler and extending to, and in fluid communication with the low pressure exhaust gas recirculation branch; and
a bypass valve disposed in the exhaust gas diverter branch and operable to divert high temperature, un-cooled exhaust gas from the exhaust gas recirculation conduit and to the low pressure exhaust gas recirculation branch.
16. The internal combustion engine of claim 15, further comprising:
a controller in signal communication with the internal combustion engine and the bypass valve and configured to operate the valve to vary a temperature of exhaust gas flowing to the low pressure exhaust gas recirculation branch and the intake system of the internal combustion engine.