Patent Application
20130233997
The subject matter disclosed herein relates generally to an engine mounting configuration and, in particular, to an engine mounting configuration for mounting a turbofan gas turbine engine to an aircraft pylon.
A gas turbine engine may be mounted at various points on an aircraft such as a pylon integrated with an aircraft structure. An engine mounting configuration ensures the transmission of loads between the engine and the aircraft structure. The loads typically include the weight of the engine, its thrust, aerodynamic loads, maneuver loads, and rotary torque about the engine axis. The engine mounting configuration must also absorb the deformations to which the engine is subjected during different flight phases and the dimensional variations due to thermal expansion and retraction.
One conventional engine mounting configuration includes a pylon having a forward mount and an aft mount. The front fan case mount handles the vertical and side loads from the front of the engine. The rear mount handles vertical and side loads from the rear of the engine, engine torque, and thrust through a set of thrust links reaching from the rear mount forward to the intermediate case.
External components including mounts, electrical systems, lubrication systems, fuel systems, and the like all reside on the outside shell of the engine core. As engines are becoming small in core size, these components tend not to scale linearly, if at all, in size causing an issue for the proper attachment of the hardware to the smaller sized engine casings. The typical mounting systems include numerous poles and brackets, which extend into areas also needed for the additional hardware. A system that would reduce the size of the mounting system, and thus the time to attach the engine to an aircraft, would prove beneficial.
In one embodiment, a mount for a turbine engine has a semi-circular yoke with a first leg and a second leg. The mount also has a stanchion with a cylindrical section attached to the yoke, and a conical section attached to the cylindrical section. A mounting bracket is attached to the conical section.
In another embodiment, a gas turbine engine mounting configuration has a pylon, and a turbine engine case mount attached to the pylon. The mount has a yoke having a first leg and a second leg, a support post attached to the yoke, and a mounting bracket attached to the support post.
High pressure compressor 18 and high pressure turbine 24 are connected by a common shaft, while low pressure compressor 16 and low pressure turbine 22 are similarly connected by a second shaft. The shafts are co-axial about a central axis of turbofan engine 10. Combustor 20 is arranged between high pressure compressor 18 and high pressure turbine 24. Airflow enters fan 26 and nacelle 14 which at least partially surrounds the core engine. Fan section 26 communicates airflow into nacelle 14 to low pressure compressor 16. Core airflow is compressed by low pressure compressor 16 and high pressure compressor 18, and then is mixed with the fuel in combustor 20 where the fuel is ignited, and burned. The resultant combustor products and exhaust are expanded through high pressure turbine 24 and low pressure turbine 22. Turbines 22 and 24 are rotationally coupled to compressors 16 and 18, respectively to drive compressors 16 and 18 in response to the expansion of the combustion process. Low pressure turbine 22 also drives fan section 26. A core engine exhaust exits turbine engine 10 through core nozzle 30 and tail cone 32 opposite fan section 26.
Turbine engine 10 generally has case structures including fan case 34, intermediate case 36, high pressure compressor case 38, combustor case 40, low pressure turbine case 42, and turbine exhaust case 44. Fan section 26 includes fan rotor with a plurality of circumferentially spaced radially outwardly extending fan blades 46. Fan blades 46 are surrounded by fan case 34. The core engine case structures are secured to nacelle 14 via fan case 34, which is connected to inlet case 35, which includes a multiple of circumferentially spaced radially extending struts 48 which radially span the core engine case structure and fan case 34. External components including electrical systems, lubrication systems, fuel systems, and the like (not illustrated) reside on the outside of the case structure and the inside of nacelle core cowls 31 of turbine engine 10.
Turbine exhaust case 44 connects turbine engine 10 to an aircraft through an attachment to pylon 50. The attachment is made by pin 52 secured to mount 54. In the embodiment of
As illustrated in
Stanchion 66 is centrally secured to yoke 64. In the embodiment illustrated, stanchion is a vertical support post that has cylindrical section 72 attached to yoke 64, and conical section 74 attached to cylindrical section 72. Conical section 74 provides for a tapering of the cross-sectional area of stanchion 66, while cylindrical section 72 maximizes the amount of contact with pylon 50. Conical section 74 is also connected to smaller cylindrical section 76 that is attached to bracket 68. Tapering of the cross-sectional area allows for a reduced area adjacent pylon 50 where space is limited, whereas cylindrical section 72 is at an area of turbofan engine 10 that has a greater area to receive components.
Bracket 68 is D-shaped, and contains an aperture therein for receiving pin 52. The aperture may contain a spherical bearing 78. This allows bracket 68 to spin about a vertical axis A-A normal to a central axis C-C of turbine engine 10. In the embodiment illustrated and described, mount 54 allows for a determinate system having six degrees of freedom to compensate the various loads of turbine engine 10 with respect to pylon 50. Mount 54 is free to rotate about pin 52, thus allowing for T1=T2. Similarly, having only one leg to compensate for side loads S incorporates an allowance for thermal expansion and contraction of turbine exhaust case 44 during normal operation of turbofan engine 10. Having the mount legs 60 and 62 reach down to the same plane as the engine centerline, engine core bending due to thrust is eliminated.
Mount 54 eliminates the need for multiple links and bracket systems that include thrust links, connection links, and various other components for mounting turbine engine 10, as is the current state of the art illustrated in
Mount 54 is constructed from a high tensile, strong material such as steel or similar metal. Mount 54 may be machined from a solid block, or may be fabricated from several individual components secured together, such as by welding.
The following are non-exclusive descriptions of possible embodiments of the present invention.
A mount for a turbine engine has a semi-circular yoke with a first leg and a second leg. The mount also has a stanchion with a cylindrical section attached to the yoke, and a conical section attached to the cylindrical section. A mounting bracket is attached to the conical section.
The mount for the turbine engine of the preceding paragraph can optionally include, additionally and/or alternatively any, one or more of the following features, configurations and/or additional components:
the first leg and second leg may comprise apertures for receiving a first fastener and a second fastener, respectively;
the first leg and second leg may further comprise ball joints;
the first leg and the second leg may counteract vertical loads, torque and thrust loads;
the first leg may counteracts a side load;
the mounting bracket may comprise a spherical bearing; and/or
the apertures for the first fastener and the second fastener may be aligned about a diameter of a turbine engine case.
In another embodiment, a gas turbine engine mounting configuration has a pylon, and a turbine engine case mount attached to the pylon. The mount has a yoke having a first leg and a second leg, a support post attached to the yoke, and a mounting bracket attached to the support post.
The gas turbine engine mounting configuration of the preceding paragraph can optionally include, additionally and/or alternatively any, one or more of the following features, configurations and/or additional components:
the mount may attach to a turbine engine case;
the first leg may include a first attachment fastener aperture and the second leg may include a second attachment fastener aperture, the first attachment fastener aperture and the second attachment fastener aperture defined along an attachment fastener axis which extend radially inward to intersect the engine axis;
the first attachment aperture and the second attachment aperture may contain bearings;
the first leg and the second leg may counteract vertical loads, torque and thrust loads;
the first leg may also counteracts a side load;
the support post may be fixed about a vertical axis which intersects said engine axis;
the mount may comprise a spherical bearing;
the mount may be rotatable about a vertical axis which intersects said engine axis;
the pylon may attach to a fan case; and/or
the pylon may attach to an intermediate case of the gas turbine engine.
While the invention has been described with reference to an exemplary embodiment(s), it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment(s) disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.
