US3870434A - Gear arrangement for variable pitch fan - Google Patents

Gear arrangement for variable pitch fan Download PDF

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Publication number
US3870434A
US3870434A US427377A US42737773A US3870434A US 3870434 A US3870434 A US 3870434A US 427377 A US427377 A US 427377A US 42737773 A US42737773 A US 42737773A US 3870434 A US3870434 A US 3870434A
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US
United States
Prior art keywords
teeth
spaced apart
sector gears
bevel gear
blades
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US427377A
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English (en)
Inventor
Elmir Edward Paulson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
General Electric Co
Original Assignee
General Electric Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by General Electric Co filed Critical General Electric Co
Priority to US427377A priority Critical patent/US3870434A/en
Priority to DE19742459843 priority patent/DE2459843A1/de
Priority to FR7441949A priority patent/FR2255488B3/fr
Priority to JP49145870A priority patent/JPS5095613A/ja
Priority to BE151754A priority patent/BE823650A/xx
Application granted granted Critical
Publication of US3870434A publication Critical patent/US3870434A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D7/00—Rotors with blades adjustable in operation; Control thereof
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/26—Rotors specially for elastic fluids
    • F04D29/32—Rotors specially for elastic fluids for axial flow pumps
    • F04D29/321—Rotors specially for elastic fluids for axial flow pumps for axial flow compressors
    • F04D29/322—Blade mountings
    • F04D29/323—Blade mountings adjustable
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2220/00—Application
    • F05D2220/30—Application in turbines
    • F05D2220/36—Application in turbines specially adapted for the fan of turbofan engines
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2260/00—Function
    • F05D2260/70—Adjusting of angle of incidence or attack of rotating blades
    • F05D2260/74—Adjusting of angle of incidence or attack of rotating blades by turning around an axis perpendicular the rotor centre line
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2260/00—Function
    • F05D2260/70—Adjusting of angle of incidence or attack of rotating blades
    • F05D2260/76—Adjusting of angle of incidence or attack of rotating blades the adjusting mechanism using auxiliary power sources
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T50/00—Aeronautics or air transport
    • Y02T50/60—Efficient propulsion technologies, e.g. for aircraft

Definitions

  • a variable pitch fan having a plurality of circumferentially spaced apart variable pitch fan blades journalled for rotation about their longitudinal axes in a hub member, further includes a plurality of sector gears drivably connected to the rotor blades and simultaneously actuated by a unison bevel gear wherein each sector gear operates to apply its highest torque to the blades during the cruise mode of engine operation when the inherent turning moments from the centrifugal forces operating on the blades are at their peak.
  • This arrangement relates to a gear arrangement for a variable pitch fan and, more particularly, to sector gear arrangement for simultaneously varying the pitch of a plurality of spaced apart variable pitch fan blades journalled in a hub member.
  • variable pitch fan During normal operation of a variable pitch fan, the individual fan blades incur a high dynamic turning moment due to the high centrifugal forces which operate to rotate the blades about their longitudinal center axes such that the major surfaces of each airfoil vane tend to become aligned normal to the center axis of rotation and thus block the airflow through the fan blades. Additional information regarding the inherent turning moments of variable pitch fan blades may be found in U.S. Pat. No. 2,844,303 dated July 22, 1958.
  • the gear arrangement of this invention is provided for a turbomachine of the type having a plurality of spaced apart variable pitch blades journalled in a rotatable hub member.
  • the gear arrangement includes a plurality of spaced apart sector gears in respective driving engagement with the blades wherein each gear has a plurality of teeth spaced apart at varying distances along the length of a conical surface of revolution.
  • a unison bevel gear also having a plurality of circumferentially spaced apart teeth for simultaneously engaging the teeth of the sector gears.
  • FIG. 1 is a partial cross-sectional view of the gear arrangement and variable pitch fan of this invention.
  • FIG. 2 is a partial perspective view of the gear arrangement and variable pitch fan of FIG. 1.
  • FIG. 3 is a partial perspective view of the cruise mode of operation for the gear arrangement and variable pitch fan of FIG. 1.
  • FIG. 4 is a partial perspective view of the transition mode of operation for the gear arrangement and variable pitch fan of FIG. 1.
  • FIG. 5 is a partial perspective view of the reverse mode of operation for the gear arrangement and variable pitch fan of FIG. 1.
  • FIG. 6 is a partial perspective view of an alternate embodiment of the gear arrangement and variable pitch fan of FIG. 1.
  • variable pitch fan 10 which is suitable for attachment to the forward end of a gas turbine engine (not shown).
  • the variable pitch fan 10 includes a plurality of circumferentially spaced apart variable pitch fan blades 12 disposed about an inner fairing 14 which extends forwardly of the variable pitch blades 12 and defines an upstream spinner 16.
  • a static bypass duct 11 is provided between the inner fairing l4 and an outer spaced apart cowling 13.
  • the gas turbine engine may be of a conventional type having a compressor section, a combustion section (not shown), and a turbine section (not shown) arranged in serial flow relation on either a single shaft or a dual shaft (not shown).
  • the variable pitch fan blades 12, together with the inner fairing 14 and the spinner 16, are all interconnected for rotation about a longitudinal engine center axis A by a rotating frame structure (also not shown) as is well known in the gas turbine art.
  • the outline of only the forward end of the compressor is illustrated at 18 and defines a compressor inlet 20 communicating with a plurality of rotatable compressor blades 22 interspaced between a plurality of stator vanes 24 which may be of the variable type.
  • the compressor is thus charged by a portion of the airflow emanating from the fan and the variation of blade pitch not only varies bypass ratio but in effect provides a variable first compressor stage.
  • a plurality of circumferentially spaced apart stator vanes 24 may be mounted between the inner fairing 14 and the outer cowling 13 aft of the variable pitch fan blading 12 and ahead of the compressor inlet 20.
  • the pitch of the fan blading 12 may be varied to reverse the airflow along the duct 11 and thus provide reverse thrust to aerodynamically brake a landing aircraft.
  • Each variable pitch fan blade 12 includes an airfoil vane portion 26 extending radially outward from a platform 28 which overhangs an inwardly directed root section 30.
  • Each root section 30 preferably includes a plurality of radially inwardly directed, spaced apart, tangs 32 which are maintained in pinned interspaced relation with a second plurality of tangs 34 extending radially outward from a root shaft 35.
  • the interspaced tangs 32 and 34 are maintained in pinned relation by a longitudinally extending pin 36 which extends through a plurality of coaxially spaced apart holes in the tangs 32, 34.
  • variable pitch fan blades The pinning of variable pitch fan blades has been found to be advantageous from a vibrational point of view and such pinned blades appear to survive under conditions which would ordinarily promote the rapid failure of fixed root blades.
  • pinning variable pitch fan blades provides an easy means for removing and replacing the fan blades. It should also be appreciated that small clearances may be provided between the pin receiving holes and the pins 36 so as to permit some rigid body motion through the rolling or slipping together of contacting surfaces. Also, by changing the pin clearances, considerable control may be had over the resonant characteristics without having to redesign the airfoil vane section 26.
  • the variable pitch fan blades have been described in a preferred embodiment with pinned roots, it will be readily apparent that the variable pitch fan blades could also be retained by conventional dovetail roots.
  • each variable pitch fan blade 12 is thickened at its inner radial end to form a circumferential flange 37 which engages a plurality of circumferentially spaced apart anti-friction bearings 38.
  • the rotating structure includes a reinforced cylindrical support or hub section 40 which has a plurality of circumferentially spaced apart radial bores 42 therethrough, each one of which receives a root shaft 35 from a variable pitch fan blade 12.
  • the radial bores 42 each include an overlapping circumferential flange portion 44 aligned in substantially opposing relation to a corresponding circumferential flange 37 so as to maintain the anti-frictionbearings 38 therebetween. In this manner, each blade is maintained for rotation about its center axis B at the high centrifugal load forces which are incurred during highspeed operation of the fan 10.
  • each of the sector gears 46 includes a plurality of circumferentially spaced apart teeth 52 extending from the outer periphery thereof for engagement with a second plurality of circumferentially spaced apart teeth 50 disposed around the periphery of a unison bevel gear 48.
  • the unison bevel gear 48 may be controlled by conventional means to rotate about the longitudinal engine axis A independently of fan rotation.
  • each airfoil vane 26 tend to'become aligned normal to the engine center axis A of fan rotation and thus block the airflow through the static bypass duct 11.
  • the individual sector gears of this invention have been specially designed to provide a high actuating torque at the normal cruise position of the variable pitch fan blades where the inherent turning moment is greatest, thus eliminating the need for any type of counterbalance weights.
  • FIG. 2 it can be seen that the teeth 52 of the sector gear 46 evolve in a spiraling helix about a conical surface of revolution shown generally by the phantom line 54 around the blade longitudinal axis B.
  • the teeth 52 are of shorter longitudinal length than the teeth 50 of the unison bevel gear 48 and thus engage the bevel gear at varying radial distances from the engine center axis A with changes in blade pitch.
  • the teeth 52 evolve a full 360 about the conical surface 54 in view of the limited range of variation of blade pitch required for normal engine operation. However, for other applications it would be possible to evolve the teeth 52 through a full 360 or more depending upon the amount of variation in blade pitch desired.
  • FIG. 3 in conjunction with the solid line airfoil vane 26 of FIG. 2, there is shown the cruise position for the variable pitch fan blades 12 wherein the inherent turning moments due to the high centrifugal forces operating on the blades are at their peak.
  • the teeth 52 which are engaged with the teeth 50 of the unison bevel gear 48 during the cruise position are at the outer end of the helical spiral, and hence apply the greatest turning moment to the root shaft 35 due to their increased diametral distance from the longitudinal blade axis B.
  • the increased diametral distance of the teeth 52 engaged with the teeth 50 of the unison bevel gear 48 there can be seen to be no interference between the non-engaged teeth 52 of adjacent sector gears 46.
  • the angle at which the teeth 50 of the unison bevel gear 48 would intersect the engine center axis A must coincide with the angle at which the conical surface of revolution 54 intersects the engine center axis A.
  • the teeth 50 and 52 may be straight, tapered, or angled, depending upon the configuration desired.
  • FIG. 4 in conjunction with the phantom line airfoil vane section 56 of FIG. 2, there is shown the position assumed by the variable pitch fan blades 12 at the instant of transition from a forward mode of propulsion to a reverse mode of propulsion.
  • the individual sector gears 46 have been rotated in a clockwise direction as viewed from the top of the variable pitch fan blades 12 and the teeth 52 engaged by the teeth 50 of the bevel gear 48 have moved radially and diametrically inward along the conical surface of revolution indicated by the phantom line 54.
  • the clockwise direction of rotation has only been arbitrarily established for purposes of illustration and that a counterclockwise direction of rotation would be equally suited for purposes of this invention.
  • the magnitude of the torque applied to the sector gears 46 by the bevel gear 48 has also correspondingly decreased due to the shortening of the effective moment arms between the bevel gear and the blade longitudinal axis B.
  • the major surfaces of the airfoil vanes 26 are also aligned normal to the engine center axis A (flat pitch) and hence the effects of the inherent turning moments which normally operate to rotate the blades about their longitudinal center axis B is negligible. Referring particularly to FIG. 4, it can be seen that the outer ends of the teeth 52 which initially engaged the unison bevel gear 48 during the cruise position do not interfere with the adjacent sector gears during blade rotation, but instead overlap the adjacen sector gears in a non-interfering manner.
  • FIG. 5 in conjunction with the phantom line airfoil vane section 58 of FIG. 2, there is shown the position assumed by the variable pitch fan blades 12 during the reverse thrust mode of operation when the direction of airflow through the bypass duct 11 is reversed.
  • the teeth 52 which engage the teeth 50 of the unison bevel gear 48 have been rotated to their radial and diametral inner limit while the non-engaged portions of the teeth 52 overlap adjacent sector gears 46 in a non-interfering manner.
  • the torque applied to the sector gears 52 is at its minimum which is entirely satisfactory due to the reduction in the inherent dynamic turning moment which operates on the blades during reverse pitch.
  • a gear arrangement comprising:
  • each gear has a plurality of teeth spaced apart at varying distances along the length of a conical surface of revolution
  • a unison bevel gear having a plurality of circumferentially spaced apart teeth in simultaneous driving engagement with the teeth of the sector gears.
  • an actuating gear arrangement comprising: I
  • each gear has a plurality of teeth spaced apart at varying distances along the length of a conical surface of revolution
  • a unison bevel gear disposed for rotation about the longitudinal engine center axis and having a plurality circumferentially spaced apart teeth disposed about the outer periphery thereof for simultaneous driving engagement with the teeth of the sector gears.
  • each sector gear which engage the teeth of the unison gear are at the outer end of the helical spiral during the cruise mode of engine operation so as to apply the greatest torque to the blade roots gears in a non-interfering manner.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
US427377A 1973-12-21 1973-12-21 Gear arrangement for variable pitch fan Expired - Lifetime US3870434A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US427377A US3870434A (en) 1973-12-21 1973-12-21 Gear arrangement for variable pitch fan
DE19742459843 DE2459843A1 (de) 1973-12-21 1974-12-18 Getriebeanordnung fuer geblaese mit variabler steigung
FR7441949A FR2255488B3 (enrdf_load_stackoverflow) 1973-12-21 1974-12-19
JP49145870A JPS5095613A (enrdf_load_stackoverflow) 1973-12-21 1974-12-20
BE151754A BE823650A (fr) 1973-12-21 1974-12-20 Agencement de pignons pour une soufflante a pas variable

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US427377A US3870434A (en) 1973-12-21 1973-12-21 Gear arrangement for variable pitch fan

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Publication Number Publication Date
US3870434A true US3870434A (en) 1975-03-11

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US427377A Expired - Lifetime US3870434A (en) 1973-12-21 1973-12-21 Gear arrangement for variable pitch fan

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US (1) US3870434A (enrdf_load_stackoverflow)
JP (1) JPS5095613A (enrdf_load_stackoverflow)
BE (1) BE823650A (enrdf_load_stackoverflow)
DE (1) DE2459843A1 (enrdf_load_stackoverflow)
FR (1) FR2255488B3 (enrdf_load_stackoverflow)

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4047840A (en) * 1975-05-29 1977-09-13 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Impact absorbing blade mounts for variable pitch blades
US4968217A (en) * 1989-09-06 1990-11-06 Rolls-Royce Plc Variable pitch arrangement for a gas turbine engine
US5022825A (en) * 1988-10-07 1991-06-11 United Technologies Corporation Pitch retention member
US5022824A (en) * 1988-10-07 1991-06-11 United Technologies Corporation Pinned airfoil propeller blade
US5129787A (en) * 1991-02-13 1992-07-14 United Technologies Corporation Lightweight propulsor blade with internal spars and rigid base members
US5205714A (en) * 1990-07-30 1993-04-27 General Electric Company Aircraft fan blade damping apparatus
WO2002055845A1 (en) 2001-01-11 2002-07-18 Paolo Pietricola A turbine engine
US20120055137A1 (en) * 2009-02-27 2012-03-08 Snecma Fan blades with cyclic setting
CN103043199A (zh) * 2013-01-17 2013-04-17 苏州船用动力系统股份有限公司 轮缘式差动端面齿调距推进装置
US20170102006A1 (en) * 2015-10-07 2017-04-13 General Electric Company Engine having variable pitch outlet guide vanes
EP3392460A1 (en) * 2017-04-21 2018-10-24 United Technologies Corporation Variable pitch fan blade system and method for adjusting the incidence angle
US20180328195A1 (en) * 2017-05-09 2018-11-15 Rolls-Royce Deutschland Ltd & Co Kg Rotor device of a turbomachine
US10494937B2 (en) * 2016-08-23 2019-12-03 MTU Aero Engines AG Inner ring for an annular guide vane assembly of a turbomachine
EP3597896A1 (en) * 2018-07-18 2020-01-22 United Technologies Corporation Boundary layer ingesting fan
US10801339B2 (en) 2017-07-11 2020-10-13 General Electric Company Aircraft gas turbine engine variable fan blade mechanism
US11073160B2 (en) 2016-09-08 2021-07-27 The United States Of America As Represented By The Secretary Of The Army Adaptable articulating axial-flow compressor/turbine rotor blade
US11125097B2 (en) * 2018-06-28 2021-09-21 MTU Aero Engines AG Segmented ring for installation in a turbomachine

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3507036A1 (de) * 1984-03-02 1985-09-12 General Electric Co., Schenectady, N.Y. Luftsteuerungseinrichtung fuer ein gasturbinentriebwerk

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US32733A (en) * 1861-07-02 Gearing for driving machinery
US1802648A (en) * 1925-12-31 1931-04-28 American Propeller Company Propeller
US2460559A (en) * 1943-10-09 1949-02-01 Wildhaber Ernest Blade pitch adjustment
US2697365A (en) * 1950-06-16 1954-12-21 Earl C Williams Power transmission equipment
US2711105A (en) * 1951-06-02 1955-06-21 Williams Earl Charles Power transmission
US2844303A (en) * 1952-08-27 1958-07-22 Nordisk Ventilator Axial blowers or fans
US3018668A (en) * 1960-09-19 1962-01-30 Bruce S Berquist Varying speed ratio gearing
US3601499A (en) * 1968-06-22 1971-08-24 Rolls Royce Gear drive for variable pitch aerofoil assembly
US3687569A (en) * 1971-03-19 1972-08-29 Gen Electric Rotor with variable angle blades

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US32733A (en) * 1861-07-02 Gearing for driving machinery
US1802648A (en) * 1925-12-31 1931-04-28 American Propeller Company Propeller
US2460559A (en) * 1943-10-09 1949-02-01 Wildhaber Ernest Blade pitch adjustment
US2697365A (en) * 1950-06-16 1954-12-21 Earl C Williams Power transmission equipment
US2711105A (en) * 1951-06-02 1955-06-21 Williams Earl Charles Power transmission
US2844303A (en) * 1952-08-27 1958-07-22 Nordisk Ventilator Axial blowers or fans
US3018668A (en) * 1960-09-19 1962-01-30 Bruce S Berquist Varying speed ratio gearing
US3601499A (en) * 1968-06-22 1971-08-24 Rolls Royce Gear drive for variable pitch aerofoil assembly
US3687569A (en) * 1971-03-19 1972-08-29 Gen Electric Rotor with variable angle blades

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4047840A (en) * 1975-05-29 1977-09-13 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Impact absorbing blade mounts for variable pitch blades
US5022825A (en) * 1988-10-07 1991-06-11 United Technologies Corporation Pitch retention member
US5022824A (en) * 1988-10-07 1991-06-11 United Technologies Corporation Pinned airfoil propeller blade
US4968217A (en) * 1989-09-06 1990-11-06 Rolls-Royce Plc Variable pitch arrangement for a gas turbine engine
US5205714A (en) * 1990-07-30 1993-04-27 General Electric Company Aircraft fan blade damping apparatus
US5129787A (en) * 1991-02-13 1992-07-14 United Technologies Corporation Lightweight propulsor blade with internal spars and rigid base members
WO2002055845A1 (en) 2001-01-11 2002-07-18 Paolo Pietricola A turbine engine
US20040042897A1 (en) * 2001-01-11 2004-03-04 Paolo Pietricola Turbine engine
US6991426B2 (en) 2001-01-11 2006-01-31 Paolo Pietricola Variable pitch fan
US9200594B2 (en) * 2009-02-27 2015-12-01 Snecma Gas turbine engine having fan blades of adjustable pitch with cyclic setting
US20120055137A1 (en) * 2009-02-27 2012-03-08 Snecma Fan blades with cyclic setting
CN103043199A (zh) * 2013-01-17 2013-04-17 苏州船用动力系统股份有限公司 轮缘式差动端面齿调距推进装置
CN103043199B (zh) * 2013-01-17 2015-05-13 苏州船用动力系统股份有限公司 轮缘式差动端面齿调距推进装置
US20170102006A1 (en) * 2015-10-07 2017-04-13 General Electric Company Engine having variable pitch outlet guide vanes
US11585354B2 (en) 2015-10-07 2023-02-21 General Electric Company Engine having variable pitch outlet guide vanes
US11391298B2 (en) * 2015-10-07 2022-07-19 General Electric Company Engine having variable pitch outlet guide vanes
US10494937B2 (en) * 2016-08-23 2019-12-03 MTU Aero Engines AG Inner ring for an annular guide vane assembly of a turbomachine
US11073160B2 (en) 2016-09-08 2021-07-27 The United States Of America As Represented By The Secretary Of The Army Adaptable articulating axial-flow compressor/turbine rotor blade
EP3392460A1 (en) * 2017-04-21 2018-10-24 United Technologies Corporation Variable pitch fan blade system and method for adjusting the incidence angle
US10738624B2 (en) * 2017-05-09 2020-08-11 Rolls-Royce Deutschland Ltd & Co Kg Rotor device of a turbomachine
US20180328195A1 (en) * 2017-05-09 2018-11-15 Rolls-Royce Deutschland Ltd & Co Kg Rotor device of a turbomachine
US10801339B2 (en) 2017-07-11 2020-10-13 General Electric Company Aircraft gas turbine engine variable fan blade mechanism
US11125097B2 (en) * 2018-06-28 2021-09-21 MTU Aero Engines AG Segmented ring for installation in a turbomachine
EP3597896A1 (en) * 2018-07-18 2020-01-22 United Technologies Corporation Boundary layer ingesting fan

Also Published As

Publication number Publication date
DE2459843A1 (de) 1975-06-26
FR2255488A1 (enrdf_load_stackoverflow) 1975-07-18
FR2255488B3 (enrdf_load_stackoverflow) 1977-09-16
JPS5095613A (enrdf_load_stackoverflow) 1975-07-30
BE823650A (fr) 1975-04-16

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