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Publication numberUS3788763 A
Publication typeGrant
Publication dateJan 29, 1974
Filing dateNov 1, 1972
Priority dateNov 1, 1972
Also published asCA973096A, CA973096A1
Publication numberUS 3788763 A, US 3788763A, US-A-3788763, US3788763 A, US3788763A
InventorsNickles L
Original AssigneeGen Motors Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Variable vanes
US 3788763 A
Abstract
An annular cascade of variable setting vanes in a compressor includes an annular row of vanes extending inward from the case and mounted on shafts extending through the case, each vane having a disk engaging the case through a bushing. Additional bushings are provided between the shaft and the case and on the exterior of the case. A washer bearing against the exterior bushing is held by a nut threaded onto the shaft and the nut is retained against rotation by a locking cup washer interlocked rotatively with the shaft. The washer and a vane actuating arm also interlocked rotatively with the shaft are retained by a cap screw threaded into the outer end of the shaft. The interior of the case preferably has a circumferential recess to receive the interior bushings of all the vanes and the interior bushing for each vane is preferably of generally rectangular outline and of varying thickness to accord with the varying spacing between the disk and the cylindrical or conical interior surface of the recess.
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United States Patent [191 Nickles VARIABLE VANES [75] Inventor? Lawrence H. Nickles, Indianapolis,

Ind.

[73] Assignee: General Motors Corporation,

Detroit, Mich.

[22] Filed: Nov. 1, 1972 [21] Appl. No.: 302,746

[52] US. Cl 415/147, 415/160 [51] Int. Cl. .1 F04d 29/52, F04d 27/00 [58] Field of Search 415/147, 149, 160

[56] References Cited UNITED STATES PATENTS 2,930,579 3/1960 Boyd et a1 415/160 3,367,628 2/1968 Fitton 415/160 3,538,579 11/1970 Sprenger 415/160 3,542,484 11/1970 Mason 415/147 3,652,177 3/1972 Loebel 415/160 3,674,377 7/1972 Trappmann 415/160 3,695,777 10/1972 Westphal et al...; 415/160 [451 Jan. 29, 1974 Primary Examinerl-lenry F. Raduazo Attorney, Agent, or Firm-Paul Fitzpatrick [5 7 ABSTRACT An annular cascade of variable setting vanes in a compressor includes an annular row of vanes extending inward from the case and mounted on shafts extending through the case, each vane having a disk engaging the case through a bushing. Additional bushings are provided between the shaft and the case and on the exterior of the case. A washer bearing against the exterior bushing is held by a nut threaded onto the shaft and the nut is retained against rotation by a locking cup washer interlocked rotatively with the shaft. The washer and a vane actuating arm also interlocked rotatively with the shaft are retained by a cap screw threaded into the outer end of the shaft. The interior of the case preferably has a circumferential recess to receive the interior bushings of all the vanes and the interior bushing for each vane is preferably of generally rectangular outline and of varying thickness to accord with the varying spacing between the disk and the cylindrical or conical interior surface of the recess.

4 Claims, 5 Drawing Figures VARIABLE VANES This invention was made inthe course of work under a contract with the Department of Defense.

My invention is directed to improvements in variable setting vane structures such as are used in turbomachines and, while capable of other uses, is particularly directed to the improvement of such structures in axialflow compressors.

Many arrangements of variable setting vane cascades have been'proposedfor compressors and other turbomachines. The purpose of suchis to adapt the operation of the machine to varying levels of flow. Examples which may be noted are described in US. patents as follows: Neumann No. 2,933,234, Apr. 19, 1960; Hall No. 2,972,441, Feb. 21, 1961I; Johnsn'No. 3,303,992, Feb. 14, 1967; and Mason No. 3,542,484, Nov. 24, 1970.

My invention is directed to providing a structure which is more feasible to manufacture and assemble and one which is more reliable and longer lasting in service than those previously known.

Features of my invention include a simple arrangement by which one threaded fastener adjusts the tightness of the bushings'which serve as bearings for the rotatable vane and another threaded fastener cooperates with means to lock the first threaded fastener in position and retains an actuating. arm for the vane; and,

' preferably, an improved arrangement of the portion of the case confronting the vanes and the bushings between that portion and the vanes to greatly simplify ma chining of the compressor case.

Other objects andadvantages of the invention-willbe apparent to those skilled inthe-art from the succeeding detailed description of preferred embodiments of the invention.

Referring to the drawings,

FIG. 1 is a sectional view, taken in a plane containing the axis of rotation of the compressor, of a portion of a variable setting angle compressor vane arrangement.

FIG. 2 is a fragmentary sectional view taken on the plane indicated by the line 2-2 in FIG. 1.

FIG. 3 is a fragmentary cross-sectional view taken on the plane indicated by the line.3--3 in FIG. 1.

FIG. 4 is a fragmentary view taken on a plane similar to that of FIG. 1 showing a preferred arrangement of vane bushings.

FIG. 5 is a fragmentary cross-sectional view of the same taken on the plane indicated by the line. 5--5 in FIG. 4. a

Referring to the drawings, FIG. 1 illustrates a portion of a compressor including a generally conical compressor case 2 which, as is often the case, converges toward the high pressure or discharge end of the compressor. The compressor case includes a thickened section 3 defining a mounting ring or support for an annular cascade of variable setting angle vanes 4. Each vane comprises an airfoil or fluid-directing portion 6, only a portion of'which is shown, the vane in this case being preferably cantilevered; that is, free from any positive support at its radially inner end. At the radially outer end of the span of the vane a disk 7 integral with the vane bears against a bushing 8 mounted in a counterbore 10 in the inner surface of the compressor case. The counterbore is concentric with a bore 11 extending through the case, and specifically through the support portion 3. The vane also includes a shaft 12 integral with the disk 7 which extends through the case. Shaft 12 includes ajournal portion 13 which is mounted in a cylindrical bushing or sleeve 14 fitted within the bore 11. Bushing 14 may be split to provide for its installation on shaft 12.

A washer-shaped outer bushing 15 is disposed between a flat surface 16 on the exterior of the case and a thrust washer 18 disposed around the shaft 12. The shaft 12 has an outer threaded portion 19 of greater diameter than the journal 13 but of slightly smaller diam eter than the bore 11 so that it can be inserted through the case. A nut 20 threaded ontothe outer portion of the shaft is run down to tighten the nut against washer 18 to produce the desired degree of tightness of fit on the thrust bearings defined by disk 7 and bushing 8 and by surface 16 and bushing 15. These bushings, and also bushing 14, are of a resilient elastomeric material which has low surface friction such as a suitable variety of polyimide; for example, that sold by DuPont under the trademark Vespel.

The extreme outer end portion 22 of shaft 12 is milled away to provide flats 23 (FIG. 2) thus defining a portion of noncircular cross-section with which a locking cup washer 24 cooperates so that the washer is nonrotatable on the shaft. An actuating arm 26 has a generally rectangular opening 27 whichfits on the noncircular portion of the shaft so that the arm is nonrotatable on the shaft. Preferably, the clearance between the opening and the flats is slight, the clearance being exaggerated for clarity in the drawings. A minimum of relative rotation between the actuating arm and shaft is preferable.

The shaft portions 19 and 22 have a threaded internal bore 28 which receives a cap screw 30. This cap screw,

acting through a washer 31, presses on arm 26 when tightened and thus presses the locking cup washer 24 down onto the hexagon nut 20. The washer thus has an interference fit with the comers of the nut to lock the nut 20 against rotation. This particular locking structure is the subject matter of my copending application for Locking Cup Washer, Ser. No. 257,885, filed May 30, 1972, of common ownership with this application, which may be referred to if needed for a more detailed explanation of the locking function of the cup washer 24.

Thus, nut 20 determines the proper tightness of the bearings which support the vane 4 and the cap screw 30 serves to retain the actuating arm 26 and to lock the nut 20 against changes in its position.

In the structure illustrated in FIGS. 1 and 3, the inner bushing 8 is lodged in a circular counterbore or spot face 32 concentric with the bore 11, one such counterbore being provided for each vane. The disk 7 rotates wihin the counterbore with some radial clearance. The counterbore arrangement of FIGS. 1 and 3 to receive the bushing 8 is generally similar to prior art disclosures. It has the practical disadvantage that it is a slow and expensive operation to machine the very considerable number of counterbores required for the vanes of a stage of a typical compressor.

FIGS. 4 and 5 illustrate a structure which, while otherwise similar to the previously described, adopts a different arrangement of the interior of the compressor case and the inner bushing to avoid such expensive machining. In the structure of FIG. 4, parts corresponding to those previously described are marked with identical numerals. In this structure, the case 42 has a mounting ring or support 43 defining the outer flat surface 16 and bore 11 as previously described. The airfoil 6, disk 7, and shaft 12 may be as previously described. Bushings l4 and 15 may also be as in the other form. The difference lies in the fact that the interior of the case has a continuous circumferential recess 44 which is slightly undercut at its forward and rear ends to provide grooves 46 and 47 which extend circumferentially. In its preferred form, the inner bushing is made up of units 48 of generally rectangualr cross section which have central holes 50 for the bushing 14 and which occupy the entire width of the counterbore so as to have the edges received within the grooves 46 and 47. The bushings 48 have exterior surfaces corresponding to the cylindrical contour of the recess 44 and interior surfaces which are flat to mate with the outer surface of the disk 7 on the vane. The bushings may have-flanges 51 at their mutally adjacent ends. As will be apparent, the machining of the recess 44 can be a single turning operation in a boring mill or the like, which is a great deal easier and quicker to accomplish than provision of an individual counterbore 10 at each vane location. Since the bushings are molded of a suitable plastic material, it is a very simple matter to mold them to the desired shape.

If desired, a single integral strip may define a number of bushings 48, being provided with holes 50 at each vane position.

The assembly of the vanes into the case is very simple; the bushings 14 are disposed around the portion 13 of shaft 12 and the inner bushings 8 or 48 are laid against the outer surface of the disk 7 or inner surface of thecase. The shaft is then inserted through the case from the inside and outer bushing 15 and washer 18 are applied. Then nut 20 is tightened to provide the desired degree of tightness of the bushings. It will be understood that it is desired to minimize leakage and at the same time not to create undue resistance to rotation of the vane shafts. When this adjustment is completed, the washer 24, arm 26, and washer 31 are put in place and screw is tightened to hold these properly assembled.

At the time of this assembly, the arms 26 are preferably already coupled to a unison ring 60 by which the arms 26 are rotated in unison to adjust the vanes 4 concurrently. j

The preferred structure for connecting each arm 26 to ring 60 comprises a spherical bearing 62, the outer member of which is fixed to the outer end of arm 26 and the inner member of which is supported in the ring 60 by a hollow rivet 63, the ends of which are expanded into conical holes 64 in the channel section ring 60. A washer 66 may be provided to take up clearance between the inner member of bearing 62 and the unison ring 60. The ring 60 may be rotated about the axis of rotation of the compressor by any suitable mechanism, which need not be described here.

The advantages of the described structures, particularly that of FIGS, 4 and 5, over prior art structure should be apparent to those skilled in the art.

The detailed description of the preferred embodiment of the invention for the purpose of explaining the principles thereof is not to be considered as limiting or restricting the invention, since many modifications may be made by the exercise of skill in the art.

I claim:

1. A variable setting vane arrangement for a fluid dynamic machine comprising, in combination, an annular support; an annular cascade of vanes extending from the support, each vane including a disk at one end of the vane and a shaft extending from the disk in a direction spanwise with respect to the vane; the support having a ring of through holes and the shafts extending through the holes, the disks being on one side of the support; an abutment adjustable axially of the shaft threaded on each shaft on the other side of the support; bushing means disposed between the support and the disk, the shaft, and the abutment; locking means mounted on the shaft engageable with the abutment to hold the abutment against rotation; an actuating arm mounted on the said shaft portion operable to rotate the shaft to vary vane settingand engaging the locking means to retain the locking means; and a fastener securing the arm to the shaft.

2. A variable setting vane arrangement for a fluid dynamic machine comprising, in combination, an annular support; an annular cascade of vanes extending from the support, each vane including a disk at one end of the vane and a shaft extending from the disk in a direction spanwise with respect to the vane; the support having a ring of through holes and the shafts extending through the holes, the disks being on one side of the support; an abutment adjustable axially of the shaft threaded on each shaft on the other side of the support; resilient antifriction bushing means disposed between the support and the disk, the shaft, and the abutment; each shaft including a portion of noncircular crosssection at the opposite side of the abutment from the support; locking means mounted on the shaft engageable with the said shaft portion and the abutment to hold the abutment against rotation; an actuating arm mounted on the said shaft portion operable to rotate the shaft to vary vane setting and engaging the locking means to retain the locking means; and a fastener securing the arm to the shaft.

3. A variable setting vane arrangement for a fluid dynamic machine comprising, in combination, an annular support; an annular cascade of vanes extending from the support, each vane including a disk at one end of the vane and a shaft extending from the disk in a directionspanwise with respect to the vane; the support having a'ring of through holes and the shafts extending through the holes, the disks being on one side of the support; an abutment adjustable axially of the shaft threaded on each shaft on the other side of the support; resilient antifriction bushing means disposed between the support and the disk, the shaft, and theabutment; each shaft including a portion of noncircular crosssection at the opposite side of the abutment from the support; locking means mounted on the shaft engageable with the said shaft portion and the abutment to hold the abutment against rotation; an actuating arm mounted on the said shaft portion operable to rotate the shaft to vary vane setting and engaging the locking means to retain the locking means; a fastener securing the arm to the shaft; the said disks having a surface normal to the axis of the shaft confronting the support and the support having a circumferential recess defined in part by a continuous surface of revolution confronting the disks; and the bushing means including portions of generally rectangular outline disposed in the recess of thickness varying with the variation of clearance between each disk and the said surface of revolution.

4. A variable setting vane arrangement for a fluid dynamic machine comprising, in combination, an annular support; an annular cascade of vanes extending radially shaft confronting the support and the support having a cirucmferential recess defined in part by a continuous surface of revolution confronting the disks; and the bushing means including portions of generally rectangular outline disposed in the recess of thickness varying with the variation of clearance between each disk and the said surface.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2930579 *Sep 19, 1955Mar 29, 1960Dominion Eng Works LtdTurbine guide vane locking and vibration preventing arrangement
US3367628 *Oct 31, 1966Feb 6, 1968United Aircraft CorpMovable vane unit
US3538579 *Jan 24, 1968Nov 10, 1970Sulzer AgMounting fixture for assembling a plural-stage axial compressor
US3542484 *Aug 19, 1968Nov 24, 1970Gen Motors CorpVariable vanes
US3652177 *May 19, 1970Mar 28, 1972Mtu Muenchen GmbhInstallation for the support of pivotal guide blades
US3674377 *Jun 17, 1970Jul 4, 1972Mtu Muenchen GmbhGuide blading for turbo machines with adjustable guide vanes
US3695777 *May 20, 1970Oct 3, 1972Motoren Turbinen UnionSupporting device for pivotal guide blades in thermal turbo-machines
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US4130375 *Oct 11, 1977Dec 19, 1978Westinghouse Canada Ltd.Vane rotator assembly for a gas turbine engine
US4139329 *May 16, 1977Feb 13, 1979Westinghouse Canada LimitedVane tip motion transfer device
US4195964 *Aug 14, 1978Apr 1, 1980Motoren- Und Turbinen-Union Munchen GmbhArrangement for reducing gap losses in the adjustable guide vanes of fluid flow machines, particularly gas turbine engines
US4808069 *Jul 3, 1986Feb 28, 1989The United States Of America As Represented By The Secretary Of The Air ForceAnti-rotation guide vane bushing
US6050775 *Nov 25, 1998Apr 18, 2000Daimlerchrysler AgRadial-flow exhaust-gas turbocharger turbine
US6450763 *Nov 17, 2000Sep 17, 2002General Electric CompanyReplaceable variable stator vane for gas turbines
US6688846 *Sep 17, 2001Feb 10, 2004Snecma MoteursDevice for controlling variable-pitch blades
US6773228 *Jul 3, 2002Aug 10, 2004General Electric CompanyMethods and apparatus for turbine nozzle locks
US6860717May 10, 2002Mar 1, 2005Avio S.P.A.Axial turbine for aeronautical applications
US6887035Oct 23, 2002May 3, 2005General Electric CompanyTribologically improved design for variable stator vanes
US7220098Dec 17, 2004May 22, 2007General Electric CompanyWear resistant variable stator vane assemblies
US7223066May 13, 2004May 29, 2007Rolls-Royce PlcVariable vane arrangement for a turbomachine
US7281892Jan 31, 2005Oct 16, 2007Snecma MoteursControl lever for the pitch angle of a blade in a turbomachine
US7448848Aug 2, 2005Nov 11, 2008United Technologies CorporationVariable vane arm/unison ring attachment system
US7543992Oct 5, 2005Jun 9, 2009General Electric CompanyHigh temperature rod end bearings
US7802963 *Feb 14, 2006Sep 28, 2010Rolls-Royce PlcPivot ring
US8038387Jun 20, 2007Oct 18, 2011SnecmaBearing for variable pitch stator vane
US8414248 *Dec 3, 2009Apr 9, 2013Rolls-Royce CorporationVariable geometry vane
US8668444 *Sep 28, 2010Mar 11, 2014General Electric CompanyAttachment stud for a variable vane assembly of a turbine compressor
US8714916 *Sep 28, 2010May 6, 2014General Electric CompanyVariable vane assembly for a turbine compressor
US9297297 *Aug 31, 2012Mar 29, 2016Hyundai Motor CompanyWasher for reducing noise and system for reducing noise of wastegate valve apparatus by using the same
US9404374 *Apr 9, 2008Aug 2, 2016United Technologies CorporationTrunnion hole repair utilizing interference fit inserts
US20020182064 *May 10, 2002Dec 5, 2002Fiatvio S.P.A.Axial turbine for aeronautical applications
US20040005217 *Jul 3, 2002Jan 8, 2004Rainous Edward AtwoodMethods and apparatus for turbine nozzle locks
US20040022632 *Feb 24, 2003Feb 5, 2004Thut Bruno H.Impeller for molten metal pump with reduced clogging
US20040240990 *May 13, 2004Dec 2, 2004Rockley Christopher I.Variable vane arrangement for a turbomachine
US20050175445 *Jan 31, 2005Aug 11, 2005Snecma MoteursControl lever for the pitch angle of a blade in a turbomachine
US20050232757 *Dec 17, 2004Oct 20, 2005General Electric CompanyWear resistant variable stator vane assemblies
US20060029494 *Oct 5, 2005Feb 9, 2006General Electric CompanyHigh temperature ceramic lubricant
US20060198982 *Feb 14, 2006Sep 7, 2006Holland Clive RPivot ring
US20060245676 *Oct 5, 2005Nov 2, 2006General Electric CompanyHigh temperature rod end bearings
US20070215505 *Aug 7, 2006Sep 20, 2007Walker Terry DShrink-Wrap Packaging Incorporating Reinforced Integral Handle
US20080031730 *Jun 20, 2007Feb 7, 2008SnecmaBearing for variable pitch stator vane
US20100166540 *Dec 3, 2009Jul 1, 2010Perez Lucas RVariable geometry vane
US20110110783 *Apr 9, 2008May 12, 2011United Technologies CorporationTrunnion hole repair utilizing interference fit inserts
US20120076641 *Sep 28, 2010Mar 29, 2012General Electric CompanyVariable vane assembly for a turbine compressor
US20120076658 *Sep 28, 2010Mar 29, 2012General Electric CompanyAttachment stud for a variable vane assembly of a turbine compressor
US20130139502 *Aug 31, 2012Jun 6, 2013Kia Motors CorporationWasher for reducing noise and system for reducing noise of wastegate valve apparatus by using the same
US20160333726 *May 15, 2015Nov 17, 2016United Technologies CorporationVane strut positioning and securing systems
CN1854469BApr 29, 2005Sep 1, 2010斯奈克玛公司Control bar for vane declination angle of turbine
CN102418712A *Sep 28, 2011Apr 18, 2012通用电气公司Variable vane assembly for a turbine compressor
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EP1256698A2 *May 10, 2002Nov 13, 2002FIATAVIO S.p.A.Axial turbine with a variable-geometry stator
EP1256698A3 *May 10, 2002Mar 10, 2004AVIO S.p.A.Axial turbine with a variable-geometry stator
EP1431520A2 *Dec 16, 2003Jun 23, 2004United Technologies CorporationVariable vane arm/unison ring attachment system
EP1431520A3 *Dec 16, 2003Sep 27, 2006United Technologies CorporationVariable vane arm/unison ring attachment system
EP1431521A2 *Dec 16, 2003Jun 23, 2004General Electric CompanyMethods and apparatus for sealing gas turbine engine variable vane assemblies
EP1431521A3 *Dec 16, 2003Aug 23, 2006General Electric CompanyMethods and apparatus for sealing gas turbine engine variable vane assemblies
EP1564381A1Jan 21, 2005Aug 17, 2005Snecma MoteursActuator lever for setting the angular position of guide vanes in a turbo machine
EP1777375A1 *Sep 18, 2006Apr 25, 2007SnecmaBearing device of a variable guide vane in an axial turbomachine
EP1870600A1 *Jun 20, 2007Dec 26, 2007SnecmaBearing for stator vane with variable setting
EP2273074A1 *Dec 16, 2003Jan 12, 2011United Technologies CorporationVane arm
Classifications
U.S. Classification415/147, 415/160
International ClassificationF01D17/00, F04D29/32, F01D17/16
Cooperative ClassificationF01D17/162, F04D29/323
European ClassificationF04D29/32B2B, F01D17/16B