`(12) Patent Application Publication (10) Pub. No.: US 2009/0314881 A1
`Suciu et al.
`(43) Pub. Date:
`Dec. 24, 2009
`
`US 20090314881A1
`
`(54) ENGINE MOUNT SYSTEM FORA
`TURBOFAN GAS TURBINE ENGINE
`
`(76) Inventors:
`
`Gabriel L. Suciu, Glastonbury, CT
`(Us); Brian D_ Merry’ Andover,
`CT (US); Christopher M. Dye,
`South Windsor, CT (US); Steven B.
`J°h“s°“’ Marlborough’ CT (Us)
`
`(21) Appl. No.:
`
`12/131,876
`
`(22) Filed:
`
`Jun. 2, 2008
`_
`_
`_
`_
`Publication Classi?cation
`
`(51) Int_ CL
`(200601)
`B64D 27/10
`(52) us. Cl. ........................................................ .. 244/54
`
`Correspondence Address:
`CARLSON, GASKEY & OLDS/PRATT & WHIT
`NEY
`400 WEST MAPLE ROAD, SUITE 350
`BIRMINGHAM, MI 48009 (US)
`
`(57)
`
`ABSTRACT
`
`A mount system for a gas turbine engine includes an aft
`mount Which reacts at least a portion of a thrust load at an
`engine case generally parallel to an engine axis.
`
`10\
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`12
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`II
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`/
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`25
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`20
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`GE v. UTC
`IPR2016-00952
`GE-1024.001
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`Patent Application Publication
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`Dec. 24, 2009 Sheet 1 0f 11
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`US 2009/0314881 A1
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`GE v. UTC
`IPR2016-00952
`GE-1024.002
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`Patent Application Publication
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`Dec. 24, 2009 Sheet 2 0f 11
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`US 2009/0314881 A1
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`wm
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`Lqm 0mm mwm
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`m:
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`ow
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`GE v. UTC
`IPR2016-00952
`GE-1024.003
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`Patent Application Publication
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`Dec. 24, 2009 Sheet 3 0f 11
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`US 2009/0314881 A1
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`amiss
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`GE v. UTC
`IPR2016-00952
`GE-1024.004
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`Patent Application Publication
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`Dec. 24, 2009 Sheet 4 of 11
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`US 2009/0314881 A1
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`GE v. UTC
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`|PR2016-00952
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`GE-1024.005
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`GE v. UTC
`IPR2016-00952
`GE-1024.005
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`
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`Patent Application Publication
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`Dec. 24, 2009 Sheet 5 0f 11
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`FKiA
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`GE v. UTC
`IPR2016-00952
`GE-1024.006
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`Patent Application Publication
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`Dec. 24, 2009 Sheet 6 0f 11
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`GE v. UTC
`IPR2016-00952
`GE-1024.007
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`Patent Application Publication
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`Dec. 24, 2009 Sheet 7 0f 11
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`GE v. UTC
`IPR2016-00952
`GE-1024.008
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`Patent Application Publication
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`Dec. 24, 2009 Sheet 8 0f 11
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`GE v. UTC
`IPR2016-00952
`GE-1024.009
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`Patent Application Publication
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`Dec. 24, 2009 Sheet 9 0f 11
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`r
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`1 04B
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`GE v. UTC
`IPR2016-00952
`GE-1024.010
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`Patent Application Publication
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`Dec. 24, 2009 Sheet 10 0f 11
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`US 2009/0314881 A1
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`VERTICAL LOAD
`ONLY
`
`VERTICAL/SIDE
`LOADS
`A
`
`THRUST
`LOAD
`
`GE v. UTC
`IPR2016-00952
`GE-1024.011
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`Patent Application Publication
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`Dec. 24, 2009 Sheet 11 0f 11
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`US 2009/0314881 A1
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`GE v. UTC
`IPR2016-00952
`GE-1024.012
`
`
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`US 2009/0314881 A1
`
`Dec. 24, 2009
`
`ENGINE MOUNT SYSTEM FORA
`TURBOFAN GAS TURBINE ENGINE
`
`BACKGROUND
`
`[0001] The present invention relates to a gas turbine engine
`and more particularly to an engine mounting con?guration
`for the mounting of a turbofan gas turbine engine to an aircraft
`pylon.
`[0002] 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 con?guration ensures the
`transmission of loads betWeen the engine and the aircraft
`structure. The loads typically include the Weight of the
`engine, thrust, aerodynamic side loads, and rotary torque
`about the engine axis. The engine mount con?guration must
`also absorb the deformations to Which the engine is subjected
`during different ?ight phases and the dimensional variations
`due to thermal expansion and retraction.
`[0003] One conventional engine mounting con?guration
`includes a pylon having a forWard mount and an aft mount
`With relatively long thrust links Which extend forWard from
`the aft mount to the engine intermediate case structure.
`Although effective, one disadvantage of this conventional
`type mounting arrangement is the relatively large “punch
`loads” into the engine cases from the thrust links Which react
`the thrust from the engine and couple the thrust to the pylon.
`These loads tend to distort the intermediate case and the loW
`pressure compressor (LPC) cases. The distortion may cause
`the clearances betWeen the static cases and rotating blade tips
`to increase Which may negatively affect engine performance
`and increase fuel burn.
`
`SUMMARY
`
`[0004] A mount system for a gas turbine engine according
`to an exemplary aspect of the present invention includes an aft
`mount Which reacts at least a portion of a thrust load at an
`engine case generally parallel to an engine axis.
`[0005] A mount system for a gas turbine engine according
`to an exemplary aspect of the present invention includes a
`Wif?e tree assembly mounted to a pylon through a ?rst Wif?e
`tree ball link; a ?rst A-ar'm mounted to the rear mount plat
`form through a ?rst A-arm ?rst ball joint, the Wif?e tree
`assembly though a ?rstA-arm sliding ball joint and the engine
`case through a ?rst A-arm second ball joint; and a second
`A-arm mounted to the rear mount platform through a second
`A-arm ?rst balljoint, the Wif?e tree assembly though a second
`A-arm sliding ball joint and the engine case through a second
`A-arm second ball joint.
`[0006] A method for mounting a gas turbine engine accord
`ing to an exemplary aspect of the present invention includes
`positioning the aft mount betWeen the engine case and the
`pylon to react a least a vertical load, a side load and a thrust
`load at a rear mount platform mounted to the pylon; connect
`ing a ?rst and second A-ar'm of the aft mount betWeen a rear
`mount platform through a respective ball joint and the engine
`case to react a thrust vector of the thrust load at the engine case
`generally parallel to an engine axis; and connecting a Wif?e
`tree assembly betWeen the ?rst and second A-arm and the
`pylon through though a respective sliding ball joint, to react
`only a vertical load transverse to the engine axis.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`[0007] The various features and advantages of this inven
`tion Will become apparent to those skilled in the art from the
`
`folloWing detailed description of the currently disclosed
`embodiment. The draWings that accompany the detailed
`description can be brie?y described as folloWs:
`[0008] FIG. 1A is a general schematic sectional vieW
`through a gas turbine engine along the engine longitudinal
`axis;
`[0009] FIG. 1B is a general sectional vieW through a gas
`turbine engine along the engine longitudinal axis illustrating
`an engine static structure case arrangement on the loWer half
`thereof;
`[0010] FIG. 1C is a side vieW of an mount system illustrat
`ing a rear mount attached through an engine thrust case to a
`mid-turbine frame betWeen a ?rst and second bearing sup
`ported thereby;
`[0011] FIG. 1D is a forWard perspective vieW of an mount
`system illustrating a rear mount attached through an engine
`thrust case to a mid-turbine frame betWeen a ?rst and second
`bearing supported thereby;
`[0012] FIG. 2A is a top vieW of an engine mount system;
`[0013] FIG. 2B is a side vieW of an engine mount system
`Within a nacelle system;
`[0014] FIG. 2C is a forWard perspective vieW of an engine
`mount system Within a nacelle system;
`[0015] FIG. 3 is a side vieW of an engine mount system
`Within another front mount;
`[0016] FIG. 4A is an aft perspective vieW of an aft mount;
`[0017] FIG. 4B is an aft vieW ofan aft mount of FIG. 4A;
`[0018] FIG. 4C is a front vieW ofthe aft mount of FIG. 4A;
`[0019] FIG. 4D is a side vieW ofthe aft mount of FIG. 4A;
`[0020] FIG. 4E is a top vieW of the aft mount of FIG. 4A;
`[0021] FIG. 5A is a side vieW ofthe aft mount ofFIG. 4A in
`a ?rst slide position; and
`[0022] FIG. 5B is a side vieW ofthe aft mount ofFIG. 4A in
`a second slide position.
`
`DETAILED DESCRIPTION OF THE DISCLOSED
`EMBODIMENT
`
`[0023] FIG. 1A illustrates a general partial fragmentary
`schematic vieW of a gas turbofan engine 10 suspended from
`an engine pylon 12 Within an engine nacelle assembly N as is
`typical of an aircraft designed for subsonic operation.
`[0024] The turbofan engine 10 includes a core engine
`Within a core nacelle C that houses a loW spool 14 and high
`spool 24. The loW spool 14 includes a loW pressure compres
`sor 16 and loW pressure turbine 18. The loW spool 14 drives a
`fan section 20 connected to the loW spool 14 either directly or
`through a gear train 25.
`[0025] The high spool 24 includes a high pressure compres
`sor 26 and high pressure turbine 28. A combustor 30 is
`arranged betWeen the high pressure compressor 26 and high
`pressure turbine 28. The loW and high spools 14, 24 rotate
`about an engine axis of rotation A.
`[0026] The engine 10 in one non-limiting embodiment is a
`high-bypass geared architecture aircraft engine. In one dis
`closed embodiment, the engine 10 bypass ratio is greater than
`ten (10:1), the turbofan diameter is signi?cantly larger than
`that of the loW pressure compressor 16, and the loW pressure
`turbine 18 has a pressure ratio that is greater than 5:1. The
`gear train 25 may be an epicycle gear train such as a planetary
`gear system or other gear system With a gear reduction ratio of
`greater than 2.5 : 1. It should be understood, hoWever, that the
`above parameters are only exemplary of one embodiment of
`
`GE v. UTC
`IPR2016-00952
`GE-1024.013
`
`
`
`US 2009/0314881A1
`
`Dec. 24, 2009
`
`a geared architecture engine and that the present invention is
`applicable to other gas turbine engines including direct drive
`turbofans.
`[0027] Air?ow enters the fan nacelle P which at least par
`tially surrounds the core nacelle C. The fan section 20 com
`municates air?oW into the core nacelle C to the loW pressure
`compressor 16. Core air?oW compressed by the loW pressure
`compressor 16 and the high pressure compressor 26 is mixed
`With the fuel in the combustor 30 Where is ignited, and burned.
`The resultant high pressure combustor products are expanded
`through the high pressure turbine 28 and loW pressure turbine
`18. The turbines 28, 18 are rotationally coupled to the com
`pressors 26, 16 respectively to drive the compressors 26, 16 in
`response to the expansion of the combustor product. The loW
`pressure turbine 18 also drives the fan section 20 through gear
`train 25. A core engine exhaust E exits the core nacelle C
`through a core noZZle 43 de?ned betWeen the core nacelle C
`and a tail cone 33.
`[0028] The engine static structure 44 generally has sub
`structures including a case structure often referred to as the
`engine backbone. The engine static structure 44 generally
`includes a fan case 46, an intermediate case (IMC) 48, a high
`pressure compressor case 50, a combustor case 52A, a high
`pressure turbine case 52B, a thrust case 52C, a loW pressure
`turbine case 54, and a turbine exhaust case 56 (FIG. 1B).
`Alternatively, the combustor case 52A, the high pressure
`turbine case 52B and the thrust case 52C may be combined
`into a single case. It should be understood that this is an
`exemplary con?guration and any number of cases may be
`utiliZed.
`[0029] The fan section 20 includes a fan rotor 32 With a
`plurality of circumferentially spaced radially outWardly
`extending fan blades 34. The fan blades 34 are surrounded by
`the fan case 46. The core engine case structure is secured to
`the fan case 46 at the lMC 48 Which includes a multiple of
`circumferentially spaced radially extending struts 40 Which
`radially span the core engine case structure and the fan case
`20.
`[0030] The engine static structure 44 further supports a
`bearing system upon Which the turbines 28, 18, compressors
`26, 16 and fan rotor 32 rotate. A #1 fan dual bearing 60 Which
`rotationally supports the fan rotor 32 is axially located gen
`erally Within the fan case 46. The #1 fan dual bearing 60 is
`preloaded to react fan thrust forWard and aft (in case of surge).
`A #2 LPC bearing 62 Which rotationally supports the loW
`spool 14 is axially located generally Within the intermediate
`case (IMC) 48. The #2 LPC bearing 62 reacts thrust. A #3 fan
`dual bearing 64 Which rotationally supports the high spool 24
`and also reacts thrust. The #3 fan bearing 64 is also axially
`located generally Within the IMC 48 just forWard of the high
`pressure compressor case 50. A #4 bearing 66 Which rotation
`ally supports a rear segment of the loW spool 14 reacts only
`radial loads. The #4 bearing 66 is axially located generally
`Within the thrust case 52C in an aft section thereof. A #5
`bearing 68 rotationally supports the rear segment of the loW
`spool 14 and reacts only radial loads. The #5 bearing 68 is
`axially located generally Within the thrust case 52C just aft of
`the #4 bearing 66. It should be understood that this is an
`exemplary con?guration and any number of bearings may be
`utiliZed.
`[0031] The #4 bearing 66 and the #5 bearing 68 are sup
`ported Within a mid-turbine frame (MTF) 70 to straddle radi
`ally extending structural struts 72 Which are preloaded in
`tension (FIGS. 1C-1D). The MTF 70 provides aft structural
`
`support Within the thrust case 52C for the #4 bearing 66 and
`the #5 bearing 68 Which rotatably support the spools 14, 24.
`[0032] A dual rotor engine such as that disclosed in the
`illustrated embodiment typically includes a forWard frame
`and a rear frame that support the main rotor bearings. The
`intermediate case (IMC) 48 also includes the radially extend
`ing struts 40 Which are generally radially aligned With the #2
`LPC bearing 62 (FIG. 1B). It should be understood that vari
`ous engines With various case and frame structures Will ben
`e?t from the present invention.
`[0033] The turbofan gas turbine engine 10 is mounted to
`aircraft structure such as an aircraft Wing through a mount
`system 80 attachable by the pylon 12. The mount system 80
`includes a forWard mount 82 and an aft mount 84 (FIG. 2A).
`The forWard mount 82 is secured to the IMC 48 and the aft
`mount 84 is secured to the MTF 70 at the thrust case 52C. The
`forWard mount 82 and the aft mount 84 are arranged in a plane
`containing the axis A of the turbofan gas turbine 10. This
`eliminates the thrust links from the intermediate case, Which
`frees up valuable space beneath the core nacelle and mini
`miZes lMC 48 distortion.
`[0034] Referring to FIGS. 2A-2C, the mount system 80
`reacts the engine thrust at the aft end of the engine 10. The
`term “reacts” as utiliZed in this disclosure is de?ned as
`absorbing a load and dissipating the load to another location
`of the gas turbine engine 10.
`[0035] The forWard mount 82 supports vertical loads and
`side loads. The forWard mount 82 in one non-limiting
`embodiment includes a shackle arrangement Which mounts to
`the IMC 48 at tWo points 86A, 86B. The forWard mount 82 is
`generally a plate-like member Which is oriented transverse to
`the plane Which contains engine axis A. Fasteners are oriented
`through the forWard mount 82 to engage the intermediate case
`(IMC) 48 generally parallel to the engine axis A. In this
`illustrated non-limiting embodiment, the forWard mount 82 is
`secured to the IMC 40. In another non-limiting embodiment,
`the forWard mount 82 is secured to a portion of the core
`engine, such as the high-pressure compressor case 50 of the
`gas turbine engine 10 (see FIG. 3). One of ordinary skill in the
`art having the bene?t of this disclosure Would be able to select
`an appropriate mounting location for the forWard mount 82.
`[0036] Referring to FIG. 4A, the aft mount 84 generally
`includes a ?rst A-arm 88A, a second A-arm 88B, a rear mount
`platform 90, a Wif?e tree assembly 92 and a drag link 94. The
`rear mount platform 90 is attached directly to aircraft struc
`ture such as the pylon 12. The ?rst A-arm 88A and the second
`A-arm 88B mount betWeen the thrust case 52C at case bosses
`96 Which interact With the MTF 70 (FIGS. 4B-4C), the rear
`mount platform 90 and the Wif?e tree assembly 92. It should
`be understood that the ?rst A-arm 88A and the second A-arm
`88B may alternatively mount to other areas of the engine 10
`such as the high pressure turbine case or other cases. It should
`also be understood that other frame arrangements may alter
`natively be used With any engine case arrangement.
`[0037] Referring to FIG. 4D, the ?rst A-arm 88A and the
`second A-arm 88B are rigid generally triangular arrange
`ments, each having a ?rst link arm 89a, a second link arm 89b
`and a third link arm 890. The ?rst link arm 89a is betWeen the
`case boss 96 and the rear mount platform 90. The second link
`arm 89b is betWeen the case bosses 96 and the Wif?e tree
`assembly 92. The third link arm 890 is betWeen the Wif?e tree
`assembly 92 rear mount platform 90. The ?rst A-arm 88A and
`the second A-arm 88B primarily support the vertical Weight
`
`GE v. UTC
`IPR2016-00952
`GE-1024.014
`
`
`
`US 2009/0314881A1
`
`Dec. 24, 2009
`
`load of the engine 10 and transmit thrust loads from the
`engine to the rear mount platform 90.
`[0038] The ?rst A-arm 88A and the second A-arm 88B of
`the aft mount 84 force the resultant thrust vector at the engine
`casing to be reacted along the engine axis A Which minimiZes
`tip clearance losses due to engine loading at the aft mount 84.
`This minimiZes blade tip clearance requirements and thereby
`improves engine performance.
`[0039] The Wif?e tree assembly 92 includes a Wif?e link 98
`Which supports a central ball joint 100, a ?rst sliding ball joint
`102A and a second sliding balljoint 102B (FIG. 4E). It should
`be understood that various bushings, vibration isolators and
`such like may additionally be utiliZed hereWith. The central
`ball joint 100 is attached directly to aircraft structure such as
`the pylon 12. The ?rst sliding ball joint 102A is attached to the
`?rst A-arm 88A and the second sliding ball joint 102B is
`mounted to the ?rst A-arm 88A. The ?rst and second sliding
`ball joint 102A, 102B permit sliding movement of the ?rst
`and second A-arm 88A, 88B (illustrated by arroW S in FIGS.
`5A and SE) to assure that only a vertical load is reacted by the
`Wif?e tree assembly 92. That is, the Wif?e tree assembly 92
`alloWs all engine thrust loads to be equalized transmitted to
`the engine pylon 12 through the rear mount platform 90 by the
`sliding movement and equalize the thrust load that results
`from the dual thrust link con?guration. The Wif?e link 98
`operates as an equaliZing link for vertical loads due to the ?rst
`sliding ball joint 102A and the second sliding ball joint 102B.
`As the Wif?e link 98 rotates about the central ball joint 100
`thrust forces are equaliZed in the axial direction. The Wif?e
`tree assembly 92 experiences loading only due to vertical
`loads, and is thus less susceptible to failure than conventional
`thrust-loaded designs.
`[0040] The drag link 94 includes a ball joint 104A mounted
`to the thrust case 52C and ball joint 104B mounted to the rear
`mount platform 90 (FIGS. 4B-4C). The drag link 94 operates
`to react torque.
`[0041] The aft mount 84 transmits engine loads directly to
`the thrust case 52C and the MTF 70. Thrust, vertical, side, and
`torque loads are transmitted directly from the MTF 70 Which
`reduces the number of structural members as compared to
`current in-practice designs.
`[0042] The mount system 80 is compact, and occupies
`space Within the core nacelle volume as compared to turbine
`exhaust case-mounted con?gurations, Which occupy space
`outside of the core nacelle Which may require additional or
`relatively larger aerodynamic fairings and increase aerody
`namic drag and fuel consumption. The mount system 80
`eliminates the heretofore required thrust links from the IMC,
`Which frees up valuable space adjacent the IMC 48 and the
`high pressure compressor case 50 Within the core nacelle C.
`[0043] It should be understood that relative positional
`terms such as “forWard,” “aft,” “upper,” “loWer,” “above,”
`“beloW,” and the like are With reference to the normal opera
`tional attitude of the vehicle and should not be considered
`otherWise limiting.
`[0044] The foregoing description is exemplary rather than
`de?ned by the limitations Within. Many modi?cations and
`variations of the present invention are possible in light of the
`above teachings. The disclosed embodiments of this inven
`tion have been disclosed, hoWever, one of ordinary skill in the
`art Would recogniZe that certain modi?cations Would come
`Within the scope of this invention. It is, therefore, to be under
`stood that Within the scope of the appended claims, the inven
`tion may be practiced otherWise than as speci?cally
`
`described. For that reason the folloWing claims should be
`studied to determine the true scope and content of this inven
`tion.
`What is claimed is:
`1. A mount system for a gas turbine engine comprising:
`an aft mount Which reacts at least a portion of a thrust load
`at an engine case generally parallel to an engine axis.
`2. The system as recited in claim 1, Wherein said aft mount
`is attachable to a mid-turbine frame contained at least par
`tially Within said engine case.
`3. The mount system as recited in claim 2, Wherein said aft
`mount is attachable to said mid turbine frame through said
`engine case de?ned about said engine axis.
`4. The mount system as recited in claim 2, Wherein said mid
`turbine frame supports at least one bearing.
`5. The mount system as recited in claim 1, further compris
`ing a forWard mount forWard of said aft mount along said
`engine axis, said forWard mount reacts at least a vertical load.
`6. The mount system as recited in claim 5, Wherein said
`forWard mount is attachable to an engine intermediate case.
`7. The mount system as recited in claim 5, Wherein said
`forWard mount reacts a side load.
`8. The mount system as recited in claim 1, Wherein said aft
`mount comprises:
`a rear mount platform;
`a Wif?e tree assembly;
`a ?rst A-arm mounted to said rear mount platform through
`a ?rst ball joint and said Wif?e tree assembly though a
`?rst sliding ball joint; and
`a second A-arm mounted to said rear mount platform
`through a second ball joint and said Wif?e tree assembly
`though a second sliding ball joint.
`9. The mount system as recited in claim 8, Wherein said ?rst
`A-arm and said secondA-arm each comprise a rigid generally
`triangular arrangement.
`10. The mount system as recited in claim 8, further com
`prising a drag link mounted to said rear mount platform
`through a third ball joint.
`11. A mount system for a gas turbine engine comprising:
`a pylon;
`an engine case de?ned about an engine axis of rotation;
`a rear mount platform attached to said pylon;
`a Wif?e tree assembly mounted to said pylon through a ?rst
`Wif?e tree ball link;
`a ?rst A-arm mounted to said rear mount platform through
`a ?rst A-arm ?rst ball joint, said Wif?e tree assembly
`though a ?rst A-arm sliding ball joint and said engine
`case through a ?rst A-arm second ball joint; and
`a second A-arm mounted to said rear mount platform
`through a second A-arm ?rst ball joint, said Wif?e tree
`assembly though a second A-arm sliding ball joint and
`said engine case through a second A-arm second ball
`joint.
`12. The mount system as recited in claim 11, Wherein said
`?rst A-arm and said second A-arm each comprise a rigid
`generally triangular arrangement.
`13. The mount system as recited in claim 11, further com
`prising a drag link mounted to said rear mount platform
`through a ?rst drag link ball joint and to said engine case
`through a second drag link ball joint.
`14. The mount system as recited in claim 11, Wherein said
`engine case comprises a thrust case.
`15. The mount system as recited in claim 14, Wherein said
`engine case supports a mid-turbine frame.
`
`GE v. UTC
`IPR2016-00952
`GE-1024.015
`
`
`
`US 2009/0314881A1
`
`Dec. 24, 2009
`
`16. The mount system as recited in claim 11, Wherein said
`engine case is located generally around and axially between a
`high pressure turbine and a loW pressure turbine.
`17. A method for mounting a gas turbine engine compris
`ing an engine case Which at least partially surrounds a turbine
`section, and a pylon, comprising:
`positioning a rear mount platform of an aft mount betWeen
`the engine case and the pylon to react a least a vertical
`load, a side load and a thrust load;
`connecting a ?rst and second A-arm of the aft mount
`betWeen the rear mount platform and the engine case
`through a respective ball joint to react a thrust vector of
`the thrust load at the engine case generally parallel to an
`engine axis; and
`
`connecting a Wif?e tree assembly betWeen the ?rst and
`second A-arm and the pylon through though a respective
`sliding ball joint to react only a vertical load transverse
`to the engine axis.
`18. A method as recited in claim 17, further comprising:
`connecting a drag link betWeen the engine case an the rear
`mount platform to react a torque load.
`19. A method as recited in claim 17, further comprising:
`locating the engine case generally around and axially
`betWeen a high pressure turbine and a loW pressure
`turbine.
`
`GE v. UTC
`IPR2016-00952
`GE-1024.016
`
`