Document
United States Patent 1 1 9 1
[111 4 , 0 6 8 , 4 7 0
Sargisson et al.
[ 4 5 1 Jan. 17, 1978
[54] GAS TURBINE ENGINE WITH 2,978,209 4/1961
Kerry ..................................... 244/54
3,269,118 8/1966
Benedict et al. .................... 60/39.31
CONVERTIBLE ACCESSORIES
3,478,620 11/1969 Shimanckas ....................... 74/417 X
[75] Inventors: Donald F. Sargisson; Arthur P.
3,608,684 9/1971 Shimanckas ....................... 74/417 X
Adamson, both of Cincinnati, Ohio 3,638,421 2/1972
Chilman .............................. 60/39.3 1
3,779,006 12/1973
Lewis et a l . ........................ W39.11
[73] Assignee: The United States of America as 3,786,691 1/1974
Lmdstrom ......................... 74/417 X
represented by the Administrator of
3,792,586 2/1974 Kasmarik et al. ................. 60/226 R
the National Aeronautics and Space
3,799,476 3/1974 Bouiller et al. .................... 24/60 X
Administration, Washington, D.C.
3,830,058 8/1974 Ainsworth ......................... 60/226 R
[21] Appl. No.: 522,109 Primary Examiner-Leonard H. Gerin Attorney, Agent, or Firm-Norman T. Musial; Robert C.
[22] Filed: Nov. 8, 1974 Lampe, Jr.; Derek P. Lawrence [51] Int. Cl.2 ........................ F02K 3/02; F16H 35/00; F16H 1/14 1571 ABSTRACT [52] U . S . Cl. .................................... 60/226 R; 74/385; Drive means for connecting a gas turbine engine to its 74/4 1 7 accessories are so constructed as to allow the accesso- [58] Field of Search ......................... 74/417, 423, 385; ries to be selectively positioned to any one of several 60/226 R, 39.31 predetermined ciramferential positions about the pe- [ 5 6 1 References Cited rimeter of the engine. This feature permits convenient mounting of the same engine upon vehicles demanding U.S. PATENT DOCUMENTS radically different engine mounting arrangements.
2,803,943 SA951 Rainbow ......................... 60/39.31 X
2,815,834 12/1957 Mall ................................... 74/385 X
2,932,443 4/1960 Gunberg ................................ 74/417 5 Claims, 2 Drawing Figures
U.S. Patent Jan. 17, 1978 Sheet 1 of 2 4,068,470
U.S. Patent Jan. 17, 1978
Sheet 2 of 2 4,068,470
I 7 & 7 4
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since this would preclude switching from a UTW air- GAS TURBINE ENGINE WITH CONVERTIBLE craft to an OTW aircraft without engine tear-down and ACCESSORIES reassembly to replace incompatible hardware. It is con- ceivable, as attested by the current trend of airlines to The invention described herein was made in the per- 5 standardize their fleets, that an engine could be used on formance of work under a NASA contract and is sub- more than one type of aircraft application. The problem ject to the provisions of Section 305of the National facing the engine manufacturer, therefore, is to provide Aeronautics and Space Act of 1958, Public Law an accessory arrangement which will permit engine 85-568(72 Stat. 435; 42 USC 2457). adaptation to various aircraft configurations, and addi- 10 tionally provide for nacelle steamlining. Although this BACKROUND O F THE INVENTION invention is directed particularly to aircraft propulsion This invention relates to gas turbine engines and, systems, it will become apparent that the invention is more particularly, to engine-driven accessories for use equally applicable to all vehicles utilizing gas turbine engine propulsion.
therewith.
Jet engines for powering aircraft are provided with SUMMARY O F THE INVENTION engine-driven accessories to provide essential service and regulatory functions. These accessories are typi- The object of the present invention, therefore, is to provide a convertible accessory drive arrangement, cally mounted upon the engine casing structure and, as with the remainder of the engine, are typically enclosed preferably external to the gas turbine engine nacelle, in a nacelle or other streamlined structure which enve- 2 0 which offers flexibility for varying mounting configura- lopes the engine to reduce overall aerodynamic drag. tions. This and other objects and advantages will be However, as the complexity of accessories steadily more clearly understood from the following detailed increases, and the space available within the nacelle description, drawings and specific examples, all of which are intended to be typical of rather than in any remains at best the same, the gas turbine engine designer is faced with the dilemma of where to locate the acces- way limiting to the scope of the present invention.
sories so as not to increase the nacelle diameter with Briefly stated, the above object is attained by locating consequent drag penalties. the engine accessory package external to the nacelle The problem is compounded when gas turbine de- structure such that it fits within a pocket formed within signers are also faced with having to configure their the aircraft or its pylon. A drive shaft extends from the engines for various unique applications demanding radi- 30 accessory package, through a hollow strut, into engage- cally different engine mounting arrangements. For ex- ment with the main core engine shaft drivingly connect- ing the compressor and turbine portions. At least one ample, in the aeronautics field it is contemplated that other hollow strut is provided so that, if it is desirable to the same basic aircraft engine will find application in aircraft having conventional under-the-wing (UTW) relocate the accessories, they may be removed and the 35 drive shaft withdrawn from the first strut. Subse- pylon mounting, and yet also be required for adaptation to aircraft having over-the-wing (OTW) engine mount- quently, the drive shaft may be reinstalled within the ing. The latter configuration appears extremely attrac- second hollow strut, thus re-engaging in driving con- nection the core engine shaft and the accessories.
tive for short take-off and landing (STOL) aircraft where the gas turbine engine exhaust will be used to DESCRIPTION OF THE DRAWING provide aircraft wing lift augmentation by the Coanda effect of blowing across the upper surface of a wing and FIG. 1 is a composite schematic representation of a connected flap system. gas turbine engine incorporating the subject invention, the engine being mounted in either of two different Since essential aircraft accessories are powered by configurations; and the gas turbine engine, it is common to locate the air- 45 FIG. 2 is an enlarged composite schematic represent- craft and engine accessories in close relative proximity ing one embodiment of the subject invention.
to be driven by a common engine power shaft. On ad- vanced engines such as the General Electric CF6-50 DESCRIPTION O F T H E PREFERRED engine, all engine-driven accessories are mounted on a EMBODIMENT gearbox located on the engine fan casing at the bottom Referring to the drawings wherein like numerals of the engine, within the nacelle. However, such an 50 arrangement necessitates relatively complex plumbing correspond to like elements throughout, reference is first directed to FIG. 1 wherein an engine depicted to operatively connect the accessories to the aircraft, since the accessories are located on the bottom of the generally at 10 and embodying the present invention is engine while the engine is typically suspended from the diagrammatically shown. This engine may be consid- 55 ered as comprising generally a core engine 12, a fan aircraft wing by a structure known as a pylon, the point assembly 14 including a stage of fan blades 15, and a fan of attachment being at the top of the engine.
turbine 16 which is interconnected to the fan assembly It can be appreciated, therefore, that in order to ob- 14 by shaft 18. The core engine 12 includes an axial flow tain highly streamlined nacelles such as taught in co- compressor 20 having a rotor 22. Air enters inlet 24 and pending application Ser. No. 592,108, filed Nov. 8, 60 is initially compresse;d by fan assembly 14. A first por- 1974, Adamson et ai, entitled “An Integrated Gas Tur- bine Engine-Nacelle,’’ assigned to the same assignee as tion of this compressed air enters the fan bypass duct 26 defined, in part, by core engine 12 and a circumscribing the present invention, and yet maintain flexibility in fan nacelle 28 and discharges through a fan nozzle 30. A engine mounting configurations, it would be advanta- I Y geous to have the engine-driven accessories external of second portion of the compressed air enters inlet 32, is the nacelle and located at the optimum circumferential 65 further compressed by the axial flow compressor 20 and location consistent with particular aircraft mounting. then is discharged to a combustor 34 where fuel is Ideally, any one particular engine should not be limited burned to provide high energy combustion gases which to one circumferential location for its driven accessories drive a turbine 36. The turbine 36, in turn, drives the
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rotor 22 through a shaft 38 in the usual manner of a gas cated further aft in this configuration as a result of spe- turbine engine. The hot gases of combustion then pass cial consideration and are driven by shaft 78.
to and drive the fan turbine 16 which, in turn, drives the As clearly shown in phantom in FIG. 2, the meshing fan assembly 14. A propulsive force is thus obtained by of bevel gears 60 and 62' occurs at 6 4 ' , but by virtue of the action of the fan assembly 14 discharging air from 5 bevel gears 68' and 70', the direction of rotation of the fan bypass duct 26 through the fan nozzle 30 and by accessory drive shaft 6 6 remains unchanged as depicted the discharge of combustion gases from a core engine by the rotational arrows. This ensures proper operation nozzle 40 defined, in part, by plug 42. The above de- of all accessory components without the necessity of scription is typical of many present-day gas turbine modification.
engines and is not meant to be limiting, as it will become 10 In operation, when it is desired to switch the engine readily apparent from the following descriptions that from a UTW configuration to an OTW configuration, of application to any the operator merely has to disconnect the engine acces- the present invention is capable gas turbine engine and is not necessarily restricted to sories 52 from the aircraft accessories 50, pull the engine gas turbine engines of the turbofan variety. The forego- accessories and drive shaft 56 from strut 58 and engage- ing description of the operation of the engine depicted 15 ment with core shaft 38, and reinsert the assembly into in FIG. 1 is, therefore, merely meant to be illustrative of another hollow strut 58' whereupon engagement with one type of application. core shaft 38 is re-established. Alternatively, a plurali! y Continuing with the description of the embodiment of drive shafts, such as 56 and 56, could remain operd- of the invention as depicted in the upper portion of tively connected to the core shaft 38 with the point of FIG. 1, it is shown therein that engine 10 is suspended 20 engine accessory disengagement occurring between gears 68 and 70. Appropriate blank-off plates (IS I from a pylon depicted generally at 44 which, in turn, is shown) would serve to cover the drive shafts not being suspended from and integral with an aircraft wing 46 by of truss structure 48. The aircraft propulsion it means used. This arrangement would be applicable where mounting system herein discussed is provided as an was desired to mount the engine accessories in the 25 pylon structure and have them remain there when the example of possible uses for the subject invention as it will become apparent that the invention is equally appli- engine and nacelle structure was dismounted from the cable to all vehicles utilizing gas turbine propulsion. aircraft. Such an arrangement is particularly attractive This configuration is representative of under-the-wing from an aircraft operator's point of view since he need (UTW) engine mounting. Pylon 44 is shown to include, maintain a supply of accessories approximately equal to and have disposed within, aircraft accessories depicted 30 his aircraft needs, independent of the number of spare generally at 50. Critical engine accessories depicted engines on hand. Therefore, the operator may maintain generally at 52 are located within a pocket 54 of the a minimum engine build-up unit comprising the mini- mum required engine components, thus enhancing his pylon 44 although they are an integral part of the engine quick-engine-change capability. Yet another alternative hardware. Appropriate disconnects are provided, as at 35 would include redundant drive shaft gears 62 and 55 and 57, to allow separation of the engine from the 62'(FIG. 2) permanently installed in the engine, the pylon and aircraft accessories. The engine accessories remainder of the drive shaft 56 being so constructed as are drivingly connected to the core engine 12 through a driving means, such as a drive shaft 56, which is routed to permit a driving connection with either gear. This through one of a plurality of struts 58 spanning the fan arrangement is attractive where the required size of the 40 gear is greater than the available hole through which it bypass duct 26.
Referring now to FIG. 2, there is schematically de- would otherwise have to pass.
picted in greater detail the accessory drive arrangement It should be obvious to one skilled in the art that of FIG. 1. The upper half of FIG. 2 is consistent with certain changes can be made to the above-described the OTW mounting arrangement hereinbefore dis- invention without departing from the broad inventive cussed. The core engine shaft 38 is shown to have inte- 45 concepts thereof. for example, as previously mentioned, gral therewith a first gear means, such as bevel gear 60. the above invention is applicable to any gas turbine Drive shaft 56 includes a second gear means such as engine and is not limited to those of the gas turbofan bevel gear 62, which drivingly engages bevel gear 60 as variety. Further, it is contemplated that alternative at 64. Drive shaft 56 is operatively connected to an gearing arrangements are possible in order to achieve engine accessories drive shaft 66 by known geared en- 50 the broad inventive concepts of the subject invention.
Still further, it is readily apparent that the subject inven- gagement means such as bevel gears 68 and 70, the tion is not limited to over-the-wing and under-the-wing accessory drive shaft 66 being an integral portion of the applications, but is applicable when accessories con- engine accessories denoted generally at 52. The aircraft vertibility is desired between any two or more acces- accessories, generally denoted at 50, are drivingly con- nected to the drive shaft 56 as by cooperating bevel 5 5 sory mounting locations on any gas turbine engine pro- pelled vehicle.It is intended that the appended claims gears 72 and 74, and shaft 76.
In a modified configuration shown is phantom in cover these and all similar variations of the present FIG. 1 and 2, the engine accessory package is adapted invention's broader inventive concepts.
for an over-the-wing engine mounting arrangement. As What is claimed is: depicted in phantom in FIG. 1, it is shown therein that 1. A gas turbine engine comprising: 60 a core engine including a core shaft; engine 10 is mounted over a wing 46' by means of coop- a nacelle partially circumscribing said core engine; erating pylon assembly 44'. The engine accessories 52' are here mounted below the engine, external to the first gear means within said core engine and driven by nacelle 28 and located within pylon 44'. Again, the said core shaft; engine accessories are drivingly connected to core en- a plurality of circumferentially spaced hollow struts 65 gine 12 by means of drive shaft 5 6 which has now been extending radially between said core engine and said nacelle and in general axial alignment with said inserted through a hollow strut 58' located at the bot- first gear means; tom of the engine. The aircraft accessories 50' are lo-
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r: J 4. The gas turbine engine as recited in claim 1 convertible accessory means disposed external to said wherein said first gear means is disposed upon said core nacelle and in general alignment with one of said shaft.
struts; and 5. A gas turbine engine comprising: drive shaft means, one end of which is drivingly con- a core engine including a core shaft; nected to said accessory means, and the other end a nacelle partially circumscribing said core engine; first gear means within said core engine and driven by of which includes a second gear means insertable said core shaft; into any of said hollow struts and into driving en- a plurality of circumferentially spaced hollow struts gagement with said first gear means, and 10 extending radially between said core engine and wherein said first gear means and said second gear said nacelle and in general axial alignment with said means may be disengaged by withdrawing said first gear means; drive shaft means radially outwardly with respect convertible accessory means disposed external to said nacelle and in general alignment with one of said to said core shaft.
15 struts; and 2. The gas turbine engine of claim 1 wherein said first a plurality of circumferentially spaced drive shaft gear means and said second gear means are bevel gears.
means in geared engagement with said first gear 3. The gas turbine engine of claim 2 wherein said means, and wherein said accessory means are oper- is integral with said accessory means drive shaft means atively connected to one of said drive shaft means.
* * I * * and removable from the engine therewith. 20