United States Patent [191
`Pollert et al.
`
`3,898,799
`1
`[ll
`[45] Aug. 12, 1975
`
`[54] DEVICE FOR BLEEDING'OFF
`COMPRESSOR AIR IN TURBINE JET
`ENGINE
`[75] Inventors: Wolfgang Pollert, Hebertshausen;
`Eckhard Kraft, Munich; Gregor
`Pennig, Dachau, all of Germany
`
`[73] Assignee: Motoren- und Turbinen-Union
`Munchen GmbH, Germany
`
`Sept’ 27’ 1973
`[22] Filed:
`[2 l ]
`Appl. No: 401,544
`
`[30]
`
`Foreign Application Priority Data
`Sept. 27. 1972 Germany......................,..... 2 247400
`
`60/226 R; 60/3907; 415/145
`[52] US.
`F02c 3/06
`Int. Cl.
`[51]
`[58] Field of Search............. 60/3907, 39.29, 39.23,
`60/226 R, 226 A; 415/144, 145, 28
`l57-l59, 166; 137/6253], 625.33;
`74/l59. [66
`
`7
`
`References cued
`UNITED STATES PATENTS
`
`[56]
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`3333333
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`FOREIGN PATENTS OR APPLICATIONS
`Finland
`
`10/[954
`
`27,272
`
`Primary Examiner-William L. Freeh
`Assistant Examiner-Robert E. Garrett
`Allorney, Agent, or Firm—Craig & Antonelli
`
`ABSTRACT
`[57]
`Apparatus for bleeding off compressor air in a turbine
`engine of the type having a plurality of serially ar
`ranged compressors. The apparatus includes a ?rst an
`nular chamber communicated directly with compres
`sor air from one of the compressors and a second an
`nular chamber communicated directly with atmo
`sphere or with a bypass duct of the engine. Arranged
`in between the ?rst and second chambers are internal
`and external rings slideable with respect to one an
`other with the external ring having openings which are
`controlled by the position of the internal ring. Actuat
`ing means, including a radially extending actuating
`shaft and a pair of pivotally connected levers intercon‘
`necting the internal ring and the actuating shaft are
`provided for moving the internal ring with respect to
`the external ring. The internal ring is provided with
`guide slots and the external ring is provided with guide
`rollers for guiding relative movement of the internal
`and external rings such that the internal ring simulta
`neously moves both circumferentially and axially dur
`ing adjustments thereof.
`46 Claims, 4 Drawing Figures
`
`GE v. UTC
`IPR2016-00952
`GE-1025.001
`
`

`

`PATEMEB AUG 1 2107s
`
`3.898.799
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`SHEET
`
`GE v. UTC
`IPR2016-00952
`GE-1025.002
`
`

`

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`PATENTEU AUG ? 25375
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`GE V. UTC
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`|PR2016-00952
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`GE-1025.003
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`GE v. UTC
`IPR2016-00952
`GE-1025.003
`
`

`

`1
`DEVICE FOR BLEEDING-OFF COMPRESSOR AIR
`IN TURBINE JET ENGINE
`
`3,898,799
`
`2
`tight seal at the bleed opening questionable. The pres
`ent invention also eliminates the disadvantages of this
`type of arrangement.
`These and further objects, features, and advantages
`of the present invention will become more apparent
`from the following description when taken in connec
`tion with the accompanying drawings which show, for
`purposes of illustration only, several embodiments in
`accordance with the present invention, and wherein:
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`FIG. 1 is a schematic and fragmentary sectional view
`of the top half of a turbine jet engine taken along the
`longitudinal center axis which illustrates the associa
`tion of the device according to the invention relative to
`said engine;
`FIG. 2 is a longitudinal section of the device accord
`ing to the invention arranged between a ?rst and a sec
`ond compressor, shown partially and within the bypass
`duct area only;
`FIG. 3 is a view ofa section of the device in direction
`A of FIG. 2, and
`FIG. 4 is a sectional view along line III-III of FIG. 3.
`
`20
`
`BACKGROUND AND SUMMARY OF THE
`INVENTION
`This invention relates to a device for bleeding-off
`compressor air in turbine jet engines provided with a
`plurality of mechanically independent compressors
`(compressors with compressor wheels freely rotatable
`with respect to the compressor wheels of the other
`compressors).
`In turbine jet engines with a plurality of mechanically
`independent compressors, arranged one behind the
`other, in certain operating ranges a condition may
`occur where, e.g., the speed and consequently also the
`flow supplied by a ?rst compressor is excessive relative
`to the speed of a subsequent second compressor. In
`order to avoid compressor surge it has been suggested
`to bleed off compressor air within the range of the pres
`sure gradient, i.e. in this case between the ?rst and the
`second compressor, until the most constant possible
`compressor pressure ratio within the scope of the opti
`mum engine design point is restored.
`The present invention contemplates providing a rela
`tively simple, robust and reliable device for compressor
`air bleed‘off. In addition, this device is easy to actuate,
`permits the bleed-off of a relatively large amount of
`compressor air and provides a tight seal at the compres
`sor bleed point(s) when no bleed-off is desired.
`Further, according to the present invention control
`of the bleed air ?ow is provided for adaptation to the
`prevailing operating conditions.
`The present invention further contemplates provid
`ing an internal ring adjustable both axially and tangen
`tially within a ?rst annular chamber supplied with com
`pressor air actuation of this internal ring uncovers a
`plurality of openings of an associated external ring and
`thus allows compressor air to flow into a second annu
`lar chamber located above or radially outwardly of the
`external ring and communicating with the bypass duct
`of the engine or with atmosphere.
`Furthermore, the present invention avoids the disad
`vantages of contemplated arrangements with only one
`and consequently relatively large compressor bleed air
`opening to be opened or closed so that the bleed sec
`tional area on the one hand is relatively limited and on
`the other hand an uneven load distribution occurs over
`the circumference of the compressor casing section
`concerned. In addition, the existence of only one and
`thus relatively large compressor bleed air opening re
`sults in a relatively large differential pressure between
`the chambers to be sealed and consequently in a rela
`tively large actuating force for opening or closing the
`compressor bleed air opening.
`In another contemplated arrangement the motions of
`a ring, movable both tangentially and radially are su
`perimposed to one another for opening an annular slot
`in the compressor casing section for compressor air
`bleed-off. When moved as described this ring is highly
`susceptible to tilting within the compressor casing, un
`less this ring is moved in an absolutely synchronous mo
`tion over its complete circumference. The radial mo
`tion occurring when the sliding ring is actuated gener~
`ally excludes the employment of this arrangement for
`compressor casings of relatively small diameter. In ad
`dition, this makes the requirement of an absolutely
`
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`DETAILED DESCRIPTION OF THE DRAWINGS
`The turbine jet engine shown schematically in FIG.
`1 comprises low pressure compressor 1, intermediate
`pressure compressor 2, high pressure compressor 3, an
`nular combustion chamber 5 coaxial in this case, for
`example, with the longitudinal center axis 4, followed
`by high pressure turbine 6, intermediate pressure tur
`bine 7 and low pressure turbine 8 arranged one behind
`the other. Low pressure compressor 1 and low pressure
`turbine 8 are connected by a common shaft 9. Interme
`diate pressure compressor 2 and intermediate pressure
`turbine 7 are connected to each other by means of a
`hollow shaft 10 coaxially enclosing shaft 9. Another
`hollow shaft 11 enclosing hollow shaft 10 connects high
`pressure compressor 3 with high pressure turbine 6. A
`portion of the bypass air flow supplied by low pressure
`compressor 1 enters bypass duct 12 arranged coaxially
`with the longitudinal center axis 4 of the engine and
`after joining the engine exhaust gases it ?ows into after
`burner jet pipe 13'. Between intermediate pressure
`compressor 2 and high pressure compressor 3, for ex
`ample, the device for compressor air bleed~off ex
`plained in more detail in conjunction with FIGS. 2 and
`3 is located on compressor section 13, arranged coaxi
`ally with the center longitudinal axis 4.
`As required, a portion of the air supplied by interme
`diate pressure compressor 2 can be bled off by the ap
`paratus of the present invention either into bypass duct
`12 of the engine (arrow 14) or via hollow struts 16,
`passing through bypass duct 12, to atmosphere as indi~
`cated by dotted arrow 15.
`In a turbine jet engine according to FIG. ], interme
`diate pressure compressor 2, generally indicated by
`guide vanes and rotor blades 17 and 18, respectively,
`in FIG. 2, supplies compressed air in the direction of
`arrows K into a ?rst annular chamber 19. Within this
`annular chamber 19 an internal ring 20, adjustable axi
`ally and tangentially is provided, which when actuated
`uncovers openings 21 of associated external ring 22
`and thus allows compressor air to flow into a second
`annular chamber 23, arrangedabove or radially out
`ward of external ring 22 and communicating via addi
`tional openings 24 with bypass duct 12 of the jet en
`
`GE v. UTC
`IPR2016-00952
`GE-1025.004
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`gine. This chamber 23 can alternatively be communi
`cated with atmosphere by an arrangement such as l5,
`16 of FIG. 1.
`Internal ring 20 in combination with two seal rings
`25, 26, cooperating with the inner side of external ring
`22, forms a third annular chamber 26' which is sepa
`rated from the first annular chamber 19 when the inter
`nal ring 20 is in an inoperative or closed position as il
`lustrated in FIG. 2. Ring 20 and the seal rings 25, 26,
`are slidable in circumferential (tangential) and axial
`(parallel to center line 4) to open positions where
`openings 21 of external ring 22 are in communication
`with chamber 19 (open position would be with ring 20
`and seal ring 25 and 26 moved leftward of position in
`FIG. 2).
`External ring 22 is supported elastically in radial di
`rection at its free end (left end in FIG. 2) and is pro
`vided with a seal relative to the ?rst annular chamber
`19 through seal ring 27. The right end of ring 22 is
`threadedly connected with a radially inwardly project
`ing rib of the housing.
`Inner ring 20 is actuated by means of actuating shaft
`28, passing through bypass duct 12. The torque or rota
`tional movement of the shaft 28 is transmitted to inner
`ring 20 by at least one actuating lever 29 and interme
`diate lever 30 pivotably connected to lever 29. Be
`tween actuating lever 29 and intermediate lever 30 and
`between the latter and internal ring 20 spherical bear
`ings 31, 32 are provided.
`For insuring a combined motion of internal ring 20
`in axial and circumferential direction, ring 20 is pro
`vided with guide slots 33 (FIG. 3), inclined in accor
`dance with the desired direction of rotation. A plurality
`of said guide slots, e.g. three or six are preferably
`spaced uniformly over the circumference of ring 20.
`These guide slots 33 permit positive guidance of in
`ternal ring 20 along rollers 34 (FIG. 4) which are
`mounted on external ring 22. By means of the guide
`slots 33 (FIG. 3) and the barrel-shaped rollers 34 rotat
`ing therein an axial motion is positively imposed upon
`the rotary motion effected by actuating shaft 28 (FIG.
`2) corresponding to the actuating motion of the valve
`or internal ring 20, respectively. The position‘bf rollers
`34 can be adjusted with respect to the external ring by
`means of eccentric pins 35. In this connection, the ad
`vantage is achieved of an essentially clearance-free
`support or alternative bearing of the sliding ring 20, in
`that the rollers 34 can be adjusted by means of the ec
`centric pins 35, per guide slot 33 alternatingly against
`righthand ?ank face of a guide slot and against a left
`hand ?ank face of a guide slot. FIG. 3 includes a dash
`line showing the internal ring 20 in blocking relation
`ship to the openings 21 in external ring 22. As can be
`seen in FIG. 3, a large number of openings 21 are pro
`vided on external ring 22.
`Since the chamber 19 is sealed off from the chamber
`23 when the internal ring 20 is in a position closing the
`openings 21, the compressor air from compressor 2 will
`then all be transmitted to downstream compressor 3.
`When internal ring 20 is ir a position opening the open
`ings 2 I , a portion of the compressed air from compres
`sor will be bled off via chamber 23 to atmosphere or to
`the duct A.
`The actuating shaft 28 is forcefully rotated by means
`not shown in the desired positions corresponding to the
`desired compressed air bleed-off ?ow. The control of
`this actuating shaft 28 could be responsive to sensed
`
`4
`pressures within the engine so as to assure that undesir
`able compressor surge is avoided.
`A further preferred embodiment of the present in
`vention includes thread-type spiral shaped guide slots
`in place of slots 33. (see FIG. 3)
`While we have shown and described several embodi
`ments in accordance with the present invention. it is
`understood that the same is not limited thereto but is
`susceptible of numerous changes and modi?cations as
`known to those skilled in the art, and we therefore do
`not wish to be limited to the details shown and de
`scribed herein but intend to cover all such changes and
`modi?cations as are encompassed by the scope of the
`appended claims.
`What we claim is:
`1. Apparatus for bleeding off compressor air in a tur
`bine engine of the type having a longitudinal center line
`and a plurality of mechanically independent compres
`sors', and apparatus comprising:
`a ?rst chamber communicated directly with com;
`.pressor air from one of said compressors,
`an internal ring positioned in said ?rst chamber,
`an external ring positioned downstream of said inter
`nal ring with respect to air ?ow through said tur
`bine engine, positioned adjacent and externally of
`said internal ring with respect to said center line,
`and including a plurality of openings,
`a second chamber communicated with bypass means
`of the engine which bypass means accommodates
`air ?ow therein in bypassing relationship to an en
`gine combustion chamber arranged downstream of
`said compressors,
`and internal ring actuating means for moving said in
`ternal ring between closed positions with said inter
`nal ring blocking said openings in said external ring
`to prevent ?ow from said ?rst chamber to said sec
`ond chamber and open positions with said internal
`ring out of blocking relationship with respect to
`said openings such that air can flow from said ?rst
`to said second chamber through said openings.
`2. Apparatus according to claim 1, wherein each of
`said chambers are annular chambers which extend
`around said longitudinal centerline. of the engine which
`center line forms the axes of rotation for compressor
`wheels, and wherein each of said rings are annular rings
`which extend about said centerline.
`3. Apparatus according to claim 2, wherein said actu
`ating means includes means for moving said internal
`ring in both axial and circumferential directions with
`respect to said centerline.
`4. Apparatus according to claim 3, further compris
`ing two annular seal rings on said internal ring which
`sealingly engage said external ring to form a third annu
`lar chamber between said internal and external rings
`which is sealed relative to said ?rst chamber when said
`internal ring is in said closed positions.
`5. Apparatus according to claim 4, wherein said ex
`ternal ring is supported elastically at one axial end
`thereof and is sealed relative to the ?rst chamber by
`seal means separate from said seal rings adjacent the
`other axial end thereof.
`6. Apparatus according to claim 3, wherein said ex
`ternal ring is supported elastically at one axial end
`thereof and is sealed relative to the ?rst chamber by
`seal means adjacent the other axial end thereof.
`7. Apparatus according to claim 1, wherein said actu
`ating means includes: a rotatable actuating shaft ex
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`5
`tending through a bypass duct of said engine in a radial
`direction with respect to said centerline, an actuating
`lever movable with said actuating shaft and an interme
`diate lever pivotally connected to both said actuating
`lever and said internal ring.
`8. Apparatus according to claim 3, wherein said actu
`ating means includes: a rotatable actuating shaft ex
`tending through a bypass duct of said engine in a radial
`direction with respect to said centerline, an actuating
`lever movable with said actuating shaft and an interme
`diate lever pivotally connected to both said actuating
`lever and said internal ring.
`9. Apparatus according to claim 5, wherein said actu
`ating means includes: a rotatable actuating shaft ex
`tending through a bypass duct of said engine in a radial
`direction with respect to said centerline, an actuating
`lever movable with said actuating shaft and an interme
`diate lever pivotally connected to both said actuating
`lever and said internal ring.
`10. Apparatus according to claim 7, wherein said ac
`tuating and intermediate levers are connected to one
`another by a ?rst spherical bearing, and wherein said
`intermediate lever and said internal ring are connected
`to one another by a second spherical bearing.
`11. Apparatus according to claim 8, wherein said ac
`tuating and intermediate levers are connected to one
`another by a ?rst spherical bearing, and wherein said
`intermediate lever and said internal ring are connected
`to one another by a second spherical bearing.
`12. Apparatus according to claim 9, wherein said ac
`tuating and intermediate levers are connected to one
`another by a first spherical bearing, and wherein said
`intermediate lever and said internal ring are connected
`to one another by a second spherical bearing.
`13. Aapparatus according to claim 1, wherein said
`actuating means includes: a plurality of circumferen
`tially spaced guide slots in said internal ring which are
`inclined in accordance with the direction of movement
`of said internal ring, and rollers mounted on said exter
`nal ring and engageable in said guide slots for ac
`comodating and guiding movement of said internal ring
`with respect to said external ring over a predetermined
`path.
`14. Apparatus according to claim 7, wherein said ac
`tuating means includes: a plurality of circumferentially
`spaced guide slots in said internal ring which are in
`clined in accordance with the direction of movement of
`said internal ring, and rollers mounted on said external
`ring and engageable in said guide slots for accommo
`dating and guiding movement of said internal ring with
`respect to said external ring over a predetermined path.
`15. Apparatus according to claim 8, wherein said ac
`tuating means includes: a plurality of circumferentially
`spaced guide slots in said internal ring which are in
`clined in accordance with the direction of movement of
`said internal ring. and rollers mounted on said external
`ring and engageable in said guide slots for accommo
`dating and guiding movement of said internal ring with
`respect to said external ring over a predetermined path.
`16. Apparatus according to claim 10, wherein said
`actuating means includes: a plurality of circumferen
`tially spaced guide slots in said internal ring which are
`inclined in accordance with the direction of movement
`of said internal ring. and rollers mounted on said exter
`nal ring and engageable in said guide slots for accom
`modating and guiding movement of said internal ring
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`with respect to said external ring over a predetermined
`path.
`17. Apparatus according to claim 11, wherein said
`actuating means includes: a plurality of circumferen
`tially spaced guide slots in said internal ring which are
`inclined in accordance with the direction of movement
`of said internal ring, and rollers mounted on said exter
`nal ring and engageable in said guide slots for accom
`modating and guiding movement of said internal ring
`with respect to said external ring over a predetermined
`path.
`18. Apparatus according to claim 13, wherein said
`rollers are adjustable by means of eccentric pins inter
`connecting them with the external ring.
`19. Apparatus according to claim 15, wherein said
`rollers are adjustable by means of eccentric pins inter
`connecting them with the external ring.
`20. Apparatus according to claim 17, wherein said
`rollers are adjustable by means of eccentric pins inter
`connecting them with the external ring.
`21. Apparatus according to claim 1, wherein said ac
`tuating means includes guide slots in one of said inter
`nal and external rings and rollers mounted in the other
`of said internal and external rings for engagement in
`said guide slots to forcibly guide relative movement of
`said external and internal rings.
`22. Apparatus according to claim 2], wherein said
`guide slots are con?gured to assure movement of said
`internal ring simultaneously in axial and circumferen
`tial directions with respect to an engine centerline.
`23. Apparatus according to claim 21, wherein each
`of said chambers are annular chambers which extend
`around said longitudinal centerline of the engine which
`center line forms the axes of rotation for the compres
`sor wheels, and wherein each of said rings are annular
`rings which extend about said centerline.
`24. Apparatus according to claim 23, wherein said
`actuating means includes means for moving said inter
`nal ring in both axial and circumferential directions
`with respect to said centerline.
`25. Apparatus according to claim 24, wherein said
`guide slots are con?gured to assure movement of said
`internal ring simultaneously in axial and circumferen
`tial directions with respect to an engine centerline.
`26. Apparatus according to claim 25, wherein said
`actuating means includes; a rotatable actuating shaft
`extending through a bypass duct of said engine in a ra
`dial direction with respect to said centerline, an actuat
`ing lever movable with said actuating shaft and an in
`termediate lever pivotally connected to both said actu
`ating lever and said internal ring.
`27. Apparatus according to claim 26, wherein said
`actuating and intermediate levers are connected to one
`another by a first spherical bearing, and wherein said
`intermediate lever and said internal ring are connected
`to one another by a second spherical bearing.
`28. Apparatus according to claim 21, wherein said
`guide slots are of thread-type spiral shape.
`29. Apparatus according to claim 27, wherein said
`guide slots are of thread-type spiral shape.
`30. Apparatus according to claim 13, wherein said
`guide slots are of thread-type spiral shape.
`31. Apparatus according to claim 3, wherein said
`openings are uniformly shaped around the circumfer
`ence of said external annular ring.
`32. Apparatus according to claim 24, wherein said
`openings are uniformly shaped around the circumfer
`
`GE v. UTC
`IPR2016-00952
`GE-1025.006
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`ence of said external annular ring, and wherein said
`guide slots are uniformly spaced around the circumfer
`ence of said rings.
`33. Apparatus for bleeding off compressor air in a
`turbine engine of the type having a longitudinal center
`line and compressor means. said apparatus comprising:
`a ?rst chamber communicated directly with com
`pressor air from said compressor means.
`a ?rst ring positioned in said ?rst chamber.
`a second ring positioned adjacent said ?rst ring and
`downstream of said ?rst ring with respect to air
`flow through said turbine engine,
`a plurality of openings in said second ring,
`a second chamber communicated with bypass means
`of the engine which bypass means accommodates
`air flow therein in bypassing relationship to an en
`gine combustion chamber arranged downstream of
`said compressor means,
`and ring actuating means for causing relative move
`ment between said first and second rings between
`closed positions with respective of said rings in
`blocking relationship to the openings in the other
`of said rings to prevent ?ow from said ?rst chamber
`to said second chamber and open positions with
`said rings out of blocking relationship of the open~
`ings such that air can flow from said ?rst to said
`second chamber through said openings.
`34. Apparatus according to claim 33, wherein said
`actuating means includes guide slots in one of said ?rst
`and second rings and rollers mounted in the other of
`said ?rst and second rings for engagement in said guide
`slots to forcibly guide relative movement of said second
`and first rings.
`35. Apparatus according to claim 34, wherein said
`guide slots are configured to assure relative movement
`of said first and second rings simultaneously in axial
`and circumferential directions with respect to an en
`gine centerline.
`36. Apparatus according to claim 35, further com
`prising two annular seal rings on said ?rst ring which
`sealingly engage said second ring to form a third annu
`lar chamber between said first and second rings which
`
`8
`is sealed relative to said ?rst chamber when said ?rst
`ring is in said closed positions.
`37. Apparatus according to claim 35, wherein said
`actuating means includes: a rotatable actuating shaft
`extending through a bypass duct of said engine in a ra
`dial direction with respect to said centerline, an actuat
`ing lever movable with said actuating shaft and an in
`termediate lever pivotally connected to’ both said actu
`ating lever and said first ring.
`,
`38. Apparatus according to claim 37, wherein said
`actuating means includes: a rotatable actuating shaft
`extending through a bypass duct of said engine in a ra—
`dial direction with respect to said centerline,lan actuat
`ing lever movable with said actuating shaft and an in
`termediate lever pivotally connected to both said actu
`ating lever and said first ring.
`}
`,
`39. Apparatus according to claim 35, wherein said
`engine includes three serially arranged compressors,
`and wherein said ?rst chamber communicates with the
`outlet of the middle one of said compressors.
`40. Apparatus according to claim 1, further compris
`ing annular seal rings movable with and provided on
`said internal ring which seal rings engage said external
`ring.
`41. Apparatus according to. claim 40, wherein said
`seal rings engage said external ring when said openings
`are in said open position.
`42. Apparatus according to claim 40, wherein said
`seal rings extend substantially radially with respect to
`said longitudinal center line.
`43. Apparatus according to claim 1, wherein said by
`pass means communicate said second chamber to at
`mosphere.
`44. Apparatus according to claim 1, wherein said by
`pass means is a bypass duct in said engine.
`45. Apparatus according to claim 33, wherein said
`bypass means communicate said second chamber to at
`mosphere.
`46. Apparatus according to claim 33, wherein said
`bypass means is a bypass duct in said engine.
`*
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