US20200023951A1 - Variable Hub-to-Hub Phasing Rotor System - Google Patents
Variable Hub-to-Hub Phasing Rotor System Download PDFInfo
- Publication number
- US20200023951A1 US20200023951A1 US15/895,589 US201815895589A US2020023951A1 US 20200023951 A1 US20200023951 A1 US 20200023951A1 US 201815895589 A US201815895589 A US 201815895589A US 2020023951 A1 US2020023951 A1 US 2020023951A1
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- US
- United States
- Prior art keywords
- rotor
- aircraft
- rotor assemblies
- phase
- phasing
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- 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.)
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C27/00—Rotorcraft; Rotors peculiar thereto
- B64C27/001—Vibration damping devices
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C11/00—Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
- B64C11/46—Arrangements of, or constructional features peculiar to, multiple propellers
- B64C11/50—Phase synchronisation between multiple propellers
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
- G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C27/00—Rotorcraft; Rotors peculiar thereto
- B64C27/001—Vibration damping devices
- B64C2027/004—Vibration damping devices using actuators, e.g. active systems
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C27/00—Rotorcraft; Rotors peculiar thereto
- B64C27/22—Compound rotorcraft, i.e. aircraft using in flight the features of both aeroplane and rotorcraft
- B64C27/30—Compound rotorcraft, i.e. aircraft using in flight the features of both aeroplane and rotorcraft with provision for reducing drag of inoperative rotor
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
- G10K2210/10—Applications
- G10K2210/123—Synchrophasors or other applications where multiple noise sources are driven with a particular phase relationship
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
- G10K2210/10—Applications
- G10K2210/128—Vehicles
- G10K2210/1281—Aircraft, e.g. spacecraft, airplane or helicopter
Definitions
- the present application relates generally to systems operably associated with aircraft rotor phasing, and more specifically, to a system configured to provide real-time rotor phasing during flight.
- Phasing is an effective method to control vibrations exerted on the aircraft during flight.
- Conventional phasing methods include the process of determining optimal offset positions of the rotor blades prior to flight, then retaining the rotor blades in the offset positions during flight.
- the pre-flight phasing process has shown to be an effective method to control vibrations during flight. Without proper phasing, vibrations on the aircraft create an uncomfortable ride, and in some cases, could cause catastrophic failure to the aircraft.
- pre-flight phasing methods have shown to be effective, it should be understood that the preset phasing is not ideal for all flight conditions.
- the aircraft performs differently than the maiden flight and/or the aircraft is required to perform under various flight conditions, e.g., bad weather conditions and/or heavier/lighter payloads.
- Conventional pre-flight phasing methods are thus limited in view of the foregoing scenarios.
- FIG. 1 is a simplified schematic of a method pursuant to a preferred embodiment of the present application
- FIG. 2 is a perspective view of a tiltrotor aircraft according to a preferred embodiment of the present application, which utilizes the method of FIG. 1 ;
- FIG. 3 is a simplified schematic of the phase angle adjustment system associated with the rotor assemblies of the tiltrotor aircraft of FIG. 2 ;
- FIGS. 4A and 4B are top views of the tiltrotor aircraft of FIG. 2 .
- the system of the present application overcomes the abovementioned problems commonly associated with conventional systems and methods to control vibrations via phasing rotor assemblies.
- the system of the present application includes a phase angle adjustment system having a phase adjustor operably associated with two or more rotor assemblies.
- the phase adjustor is configured to phase the rotor assemblies relative to each other during flight such that the rotor blades become offset at desired angles relative to each other, thereby eliminating vibrations exerted on the aircraft via the rotor assemblies.
- the vibrations are continuously monitored via phase angle adjustment system, which in turn allows real-time adjustment of the rotor assemblies during flight. Further detailed description of these features are provided below and illustrated in the accompanying drawings.
- FIG. 1 depicts a phasing process 101 in accordance with a preferred method of the present application.
- a rotor assembly 103 is operably associated with one or more sensors 105 , wherein the sensors are configured to sense vibrations exerted on the aircraft via the two or more rotor assemblies 103 .
- the sensed vibrations are relayed to a control system 107 that includes the necessary hardware, software, algorithms and the like to determine the required phasing of the rotor blades of the rotor assemblies relative to each other so as to minimize the vibrations.
- the control system 107 then commands a phase adjustor 109 , which in turn adjusts the angle orientation of the rotor blades relative to each other. This process is continuously repeated during flight such that optimal flight conditions are achieved.
- tiltrotor aircraft 201 includes rotor assemblies 213 a and 213 b that are carried by wings 215 a and 215 b, and are disposed at end portions 216 a and 216 b of wings 215 a and 215 b, respectively.
- Tilt rotor assemblies 213 a and 213 b include nacelles 220 a and 220 b, which carry the engines and transmissions of tilt rotor aircraft 201 , as well as, rotor proprotors 219 a and 219 b on forward ends 221 a and 221 b of tilt rotor assemblies 213 a and 213 b, respectively.
- Tilt rotor assemblies 213 a and 213 b move or rotate relative to wing members 215 a and 215 b between a helicopter mode in which tilt rotor assemblies 213 a and 213 b are tilted upward, such that tilt rotor aircraft 201 flies like a conventional helicopter; and an airplane mode in which tilt rotor assemblies 213 a and 213 b are tilted forward, such that tilt rotor aircraft 201 flies like a conventional propeller driven aircraft.
- the features discussed herein could also be incorporated with any type of aircraft having two or more rotor assemblies that rotate relative to each other and exert vibrations on a fuselage.
- the aircraft could include two rotor assemblies that are not adapted to pivot like a tiltrotor aircraft, but nonetheless include two or more rotor blades that rotate relative to each other, resulting in vibrations on the aircraft.
- FIG. 3 is a top cutout view of a rotor phase angle control system 300 utilized by aircraft 201 and incorporates the features of process 101 .
- the rotor phase angle control system 300 is shown operably associated with one or more of the features of aircraft 201 .
- FIG. 3 is shown without all the features of aircraft 201 .
- system 300 includes the phase adjustor 109 that is driven by the aircraft engine 301 via an input drive shaft 303 .
- the phase adjustor 109 is configured to receive the input shaft 303 and transfer the rotational movement thereof to drive the rotor assemblies 213 a, 213 b via respective output drive shafts 305 , 307 the extend through respective wings 215 a, 215 b of aircraft 201 .
- phase adjustor 203 is configured to selectively control the rotational movement of shafts 305 , 307 .
- phase adjustor 203 is adapted to adjustably offset the rotational movement output shafts 305 , 307 relative to each other, which in turn offsets the blade positions of the rotors of the rotor assemblies 213 a, 213 b relative to each other.
- phase adjustor 203 is a clutch configured to perform these features. Specifically, the clutch is configured to connect and disconnect the output shafts 305 , 307 for a predetermined time, thereby allowing the offset of the rotor blades to occur.
- phase adjustor 203 can include other devices substantially similar in function.
- FIGS. 4A and 4B are top views of aircraft 201 that illustrate the foregoing discussed method of phasing the two rotor assemblies relative to each other.
- the longitudinal lengths of the rotor blades 219 a, 219 b are aligned with each other along axis A, thus the rotor assemblies are considered to be in-phase with each other.
- the control system commands the phase adjustor to offset the rotor blades at a predetermined angle relative to each other, thereby rendering the rotor blades offset from each other and the rotor assemblies out-of-phase with each other.
- the aircraft 201 utilizes the system and methods discussed above.
Abstract
Description
- The present application relates generally to systems operably associated with aircraft rotor phasing, and more specifically, to a system configured to provide real-time rotor phasing during flight.
- The process of phasing two or more rotor blade assemblies relative to each other is well known in the art. Phasing is an effective method to control vibrations exerted on the aircraft during flight. Conventional phasing methods include the process of determining optimal offset positions of the rotor blades prior to flight, then retaining the rotor blades in the offset positions during flight. The pre-flight phasing process has shown to be an effective method to control vibrations during flight. Without proper phasing, vibrations on the aircraft create an uncomfortable ride, and in some cases, could cause catastrophic failure to the aircraft.
- Although the foregoing pre-flight phasing methods have shown to be effective, it should be understood that the preset phasing is not ideal for all flight conditions. For example, the aircraft performs differently than the maiden flight and/or the aircraft is required to perform under various flight conditions, e.g., bad weather conditions and/or heavier/lighter payloads. Conventional pre-flight phasing methods are thus limited in view of the foregoing scenarios.
- Although the foregoing developments in the field of phasing multiple rotor blade assemblies relative to each other represent great strides, many shortcomings remain.
- The novel features believed characteristic of the embodiments of the present application are set forth in the appended claims. However, the embodiments themselves, as well as a preferred mode of use, and further objectives and advantages thereof, will best be understood by reference to the following detailed description when read in conjunction with the accompanying drawings, wherein:
-
FIG. 1 is a simplified schematic of a method pursuant to a preferred embodiment of the present application; -
FIG. 2 is a perspective view of a tiltrotor aircraft according to a preferred embodiment of the present application, which utilizes the method ofFIG. 1 ; -
FIG. 3 is a simplified schematic of the phase angle adjustment system associated with the rotor assemblies of the tiltrotor aircraft ofFIG. 2 ; and -
FIGS. 4A and 4B are top views of the tiltrotor aircraft ofFIG. 2 . - While the system and method of the present application is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular embodiment disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the process of the present application as defined by the appended claims.
- Illustrative embodiments of the apparatus and method are provided below. It will of course be appreciated that in the development of any actual embodiment, numerous implementation-specific decisions will be made to achieve the developer's specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.
- The system of the present application overcomes the abovementioned problems commonly associated with conventional systems and methods to control vibrations via phasing rotor assemblies. Specifically, the system of the present application includes a phase angle adjustment system having a phase adjustor operably associated with two or more rotor assemblies. The phase adjustor is configured to phase the rotor assemblies relative to each other during flight such that the rotor blades become offset at desired angles relative to each other, thereby eliminating vibrations exerted on the aircraft via the rotor assemblies. The vibrations are continuously monitored via phase angle adjustment system, which in turn allows real-time adjustment of the rotor assemblies during flight. Further detailed description of these features are provided below and illustrated in the accompanying drawings.
- The system and method of the present application will be understood, both as to its structure and operation, from the accompanying drawings, taken in conjunction with the accompanying description. Several embodiments of the system are presented herein. It should be understood that various components, parts, and features of the different embodiments may be combined together and/or interchanged with one another, all of which are within the scope of the present application, even though not all variations and particular embodiments are shown in the drawings. It should also be understood that the mixing and matching of features, elements, and/or functions between various embodiments is expressly contemplated herein so that one of ordinary skill in the art would appreciate from this disclosure that the features, elements, and/or functions of one embodiment may be incorporated into another embodiment as appropriate, unless described otherwise.
- Referring now to the drawings wherein like reference characters identify corresponding or similar elements throughout the several views,
FIG. 1 depicts aphasing process 101 in accordance with a preferred method of the present application. As shown, arotor assembly 103 is operably associated with one ormore sensors 105, wherein the sensors are configured to sense vibrations exerted on the aircraft via the two ormore rotor assemblies 103. The sensed vibrations are relayed to acontrol system 107 that includes the necessary hardware, software, algorithms and the like to determine the required phasing of the rotor blades of the rotor assemblies relative to each other so as to minimize the vibrations. Thecontrol system 107 then commands aphase adjustor 109, which in turn adjusts the angle orientation of the rotor blades relative to each other. This process is continuously repeated during flight such that optimal flight conditions are achieved. These features provide significant advantages, namely, the process allows for real-time monitoring and phase adjustment of the rotor assemblies during flight, thereby enabling vibration control with changes in flight conditions, e.g., changes in weather and/or payload. - Referring now to
FIG. 2 in the drawings, an oblique view of atiltrotor aircraft 201 is shown utilizing thephasing process 101 discussed above. In the exemplary embodiment,tiltrotor aircraft 201 includesrotor assemblies wings end portions wings Tilt rotor assemblies nacelles tilt rotor aircraft 201, as well as, rotor proprotors 219 a and 219 b on forward ends 221 a and 221 b oftilt rotor assemblies Tilt rotor assemblies wing members rotor assemblies tilt rotor aircraft 201 flies like a conventional helicopter; and an airplane mode in which tiltrotor assemblies tilt rotor aircraft 201 flies like a conventional propeller driven aircraft. - Although shown utilized with a tiltrotor aircraft with rotor blades that rotate on the same plane, it will be appreciated that the features discussed herein could also be incorporated with any type of aircraft having two or more rotor assemblies that rotate relative to each other and exert vibrations on a fuselage. For example, in one contemplated embodiment, the aircraft could include two rotor assemblies that are not adapted to pivot like a tiltrotor aircraft, but nonetheless include two or more rotor blades that rotate relative to each other, resulting in vibrations on the aircraft.
-
FIG. 3 is a top cutout view of a rotor phaseangle control system 300 utilized byaircraft 201 and incorporates the features ofprocess 101. As shown, the rotor phaseangle control system 300 is shown operably associated with one or more of the features ofaircraft 201. For simplicity of illustration,FIG. 3 is shown without all the features ofaircraft 201. In the preferred embodiment,system 300 includes thephase adjustor 109 that is driven by theaircraft engine 301 via aninput drive shaft 303. Thephase adjustor 109 is configured to receive theinput shaft 303 and transfer the rotational movement thereof to drive therotor assemblies output drive shafts respective wings aircraft 201. - In the contemplated embodiment, the
phase adjustor 203 is configured to selectively control the rotational movement ofshafts phase adjustor 203 is adapted to adjustably offset the rotationalmovement output shafts rotor assemblies - In the preferred embodiment,
phase adjustor 203 is a clutch configured to perform these features. Specifically, the clutch is configured to connect and disconnect theoutput shafts phase adjustor 203 can include other devices substantially similar in function. -
FIGS. 4A and 4B are top views ofaircraft 201 that illustrate the foregoing discussed method of phasing the two rotor assemblies relative to each other. InFIG. 4A , the longitudinal lengths of therotor blades FIG. 4B , the control system commands the phase adjustor to offset the rotor blades at a predetermined angle relative to each other, thereby rendering the rotor blades offset from each other and the rotor assemblies out-of-phase with each other. To achieve these features, theaircraft 201 utilizes the system and methods discussed above. - It is apparent that a system and method with significant advantages has been described and illustrated. The particular embodiments disclosed above are illustrative only, as the embodiments may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. It is therefore evident that the particular embodiments disclosed above may be altered or modified, and all such variations are considered within the scope and spirit of the application. Accordingly, the protection sought herein is as set forth in the description. Although the present embodiments are shown above, they are not limited to just these embodiments, but are amenable to various changes and modifications without departing from the spirit thereof.
Claims (3)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US15/895,589 US10549849B1 (en) | 2014-02-06 | 2018-02-13 | Variable hub-to-hub phasing rotor system |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US14/174,004 US9889927B2 (en) | 2014-02-06 | 2014-02-06 | Variable hub-to-hub phasing rotor system |
US15/895,589 US10549849B1 (en) | 2014-02-06 | 2018-02-13 | Variable hub-to-hub phasing rotor system |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US14/174,004 Division US9889927B2 (en) | 2014-02-06 | 2014-02-06 | Variable hub-to-hub phasing rotor system |
Publications (2)
Publication Number | Publication Date |
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US20200023951A1 true US20200023951A1 (en) | 2020-01-23 |
US10549849B1 US10549849B1 (en) | 2020-02-04 |
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US14/174,004 Active 2036-06-09 US9889927B2 (en) | 2014-02-06 | 2014-02-06 | Variable hub-to-hub phasing rotor system |
US15/895,589 Active US10549849B1 (en) | 2014-02-06 | 2018-02-13 | Variable hub-to-hub phasing rotor system |
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US14/174,004 Active 2036-06-09 US9889927B2 (en) | 2014-02-06 | 2014-02-06 | Variable hub-to-hub phasing rotor system |
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US (2) | US9889927B2 (en) |
EP (1) | EP2905223B1 (en) |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
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US10384765B2 (en) | 2014-02-06 | 2019-08-20 | Bell Helicopter Textron Inc. | Interconnect drive system |
US10408544B2 (en) * | 2014-05-20 | 2019-09-10 | Bell Helicopter Textron Inc. | Composite top case with embedded heat pipes |
WO2016054209A1 (en) | 2014-10-01 | 2016-04-07 | Sikorsky Aircraft Corporation | Dual rotor, rotary wing aircraft |
US20170267338A1 (en) | 2014-10-01 | 2017-09-21 | Sikorsky Aircraft Corporation | Acoustic signature variation of aircraft utilizing a clutch |
US10906656B2 (en) | 2018-05-01 | 2021-02-02 | Bell Textron Inc. | Hybrid tiltrotor drive system |
US11148798B2 (en) * | 2018-06-22 | 2021-10-19 | Textron Innovations Inc. | Engine and rotatable proprotor configurations for a tiltrotor aircraft |
US10913542B2 (en) * | 2018-07-27 | 2021-02-09 | Textron Innovations Inc. | Conversion actuator and downstop striker fitting for a tiltrotor aircraft |
US10994839B2 (en) | 2018-07-31 | 2021-05-04 | Textron Innovations Inc. | System and method for rotating a rotor of a tiltrotor aircraft |
EP3626628B1 (en) | 2018-09-18 | 2021-09-01 | Bombardier Inc. | System and method for synchrophasing aircraft engines |
US10773794B2 (en) | 2019-01-10 | 2020-09-15 | Bell Textron Inc. | Dynamic rotor-phasing unit |
US11781476B2 (en) | 2019-06-25 | 2023-10-10 | Pratt & Whitney Canada Corp. | System and method for operating a multi-engine rotorcraft |
CN110901906B (en) * | 2019-12-04 | 2023-04-25 | 中国直升机设计研究所 | Ground effect rotor craft and flight mode switching method |
Family Cites Families (7)
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JPS59220622A (en) * | 1983-05-30 | 1984-12-12 | Nippon Soken Inc | Torque detector |
US5551649A (en) | 1989-10-20 | 1996-09-03 | Fokker Aircraft B.V. | Propeller blade position controller |
US5148402A (en) | 1990-12-21 | 1992-09-15 | United Technologies Corporation | Method for reducing aircraft cabin noise and vibration |
US5715162A (en) | 1992-10-13 | 1998-02-03 | United Technologies Corporation | Correlative filter for a synchrophaser |
US5453943A (en) | 1994-02-18 | 1995-09-26 | United Technologies Corporation | Adaptive synchrophaser for reducing aircraft cabin noise and vibration |
CA2683261C (en) | 2007-04-11 | 2015-06-09 | Bell Helicopter Textron Inc. | Method for suppressing vibration and acoustic signature in a tiltrotor aircraft |
US8444385B2 (en) | 2009-04-23 | 2013-05-21 | Christopher F. Yonge | Phase adjustment mechanism |
-
2014
- 2014-02-06 US US14/174,004 patent/US9889927B2/en active Active
- 2014-03-05 EP EP14157931.8A patent/EP2905223B1/en active Active
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2018
- 2018-02-13 US US15/895,589 patent/US10549849B1/en active Active
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US10549849B1 (en) | 2020-02-04 |
US9889927B2 (en) | 2018-02-13 |
US20150217863A1 (en) | 2015-08-06 |
EP2905223B1 (en) | 2015-12-30 |
EP2905223A1 (en) | 2015-08-12 |
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