Patent Grant
11156119
The present subject matter relates generally to a feedback sensor for determining a position of one ring relative to another.
A gas turbine engine generally includes a fan and a core arranged in mechanical communication with one another. Additionally, the core of the gas turbine engine general includes, in serial flow order, a compressor section, a combustion section, a turbine section, and an exhaust section. In operation, air flows through an inlet of the compressor section where one or more axial compressors progressively compress the air until it reaches the combustion section. Fuel is mixed with the compressed air and burned within the combustion section to provide combustion gases. The combustion gases are routed from the combustion section to the turbine section. The flow of combustion gasses through the combustion section drives the combustion section and is then routed through the exhaust section, e.g., to atmosphere. In particular configurations, the turbine section is mechanically coupled to the compressor section by one or more shafts extending along an axial direction of the gas turbine engine.
The fan includes a plurality of blades having a radius larger than the core of the gas turbine engine; the fan and plurality of blades being driven by or rotatable with the one or more shafts. For certain gas turbine engines, the fan is a variable pitch fan such that the plurality of blades are each rotatable about a respective pitch axis by a pitch change mechanism. The pitch change mechanism may rotate each of the plurality of blades about their respective pitch axes by changing its angular position relative to the plurality of blades and the one or more shafts.
It can be beneficial, in certain embodiments, to include a feedback sensor, to measure a position of the pitch change mechanism relative to the plurality of blades to measure the pitch of the plurality of blades. Typically, the pitch change mechanism is positioned at least partially within or adjacent to the one or more shafts. Accordingly, in order to measure a position of the pitch change mechanism relative to the plurality of blades and the one or more shafts, the one or more shafts must include elongated slots or openings to provide a sensor with a line of sight to the pitch change mechanism. However, such a configuration may weaken the one or more shafts or require additional bolstering of the one or more shafts to accommodate the elongated slots or openings. Alternatively, a sensor may be placed within the one or more shafts, the sensor connected to a controller of the gas turbine engine using, e.g., a wireless communication network. However, such a configuration can be unreliable.
Accordingly, a sensor capable of measuring a position of the pitch change mechanism relative to the one or more shafts without requiring an elongated slot or opening would be useful. More specifically, a sensor capable of measuring a position of the pitch change mechanism relative to the one or more shafts through the one or more shafts would be particularly useful.
Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.
In one exemplary embodiment of the present disclosure, a feedback sensor system is provided. The feedback sensor system includes a first ring rotatable about an axial direction. The first ring includes a surface having one or more first ring features. The feedback sensor system also includes a second ring rotatable about the axial direction. The second ring includes a surface having one or more second ring features. The feedback sensor system also includes a sensor directed at the surface of the first ring for sensing a parameter influenced by the one or more first ring features and the one or more second ring features to determine a position of the first ring relative to the second ring.
In another exemplary aspect of the present disclosure, a method is provided for determining a position of a first ring relative to a second ring in a gas turbine engine. The first ring includes a surface having one or more first ring features and the second ring includes a surface having one or more second ring features. The method includes directing a sensor towards the surface of the first ring, sensing with the sensor a parameter influenced by the one or more first ring features and the one or more second ring features, and determining a position of the first ring relative to the second ring based on the parameter sensed with the sensor.
In yet another exemplary embodiment of the present disclosure, a gas turbine engine defining an axial direction is provided. The gas turbine engine includes a turbine section mechanically coupled to a compressor section through a shaft, and a fan driven by the shaft. The fan includes a plurality of fan blades. The gas turbine engine also includes an actuation member in mechanical communication with the plurality of fan blades for changing a pitch of the plurality of fan blades. The gas turbine engine also includes a feedback sensor system. The feedback sensor system includes a first ring rotatable with the shaft of the gas turbine engine. The first ring includes a surface having one or more first ring features. The feedback sensor also includes a second ring rotatable with the actuation member of the gas turbine engine. The second ring includes a surface having one or more second ring features. The feedback sensor also includes a sensor directed at the surface of the first ring for sensing a parameter influenced by the one or more first ring features and the one or more second ring features to determine a position of the first ring relative to the second ring.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:
Reference will now be made in detail to present embodiments of the invention, one or more examples of which are illustrated in the accompanying drawings. The detailed description uses numerical and letter designations to refer to features in the drawings. Like or similar designations in the drawings and description have been used to refer to like or similar parts of the invention. As used herein, the terms “first”, “second”, and “third” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components.
Referring now to the drawings, wherein identical numerals indicate the same elements throughout the figures,
The exemplary core turbine engine 16 depicted generally includes a substantially tubular outer casing 18 that defines an annular inlet 20. The outer casing 18 encases, in serial flow relationship, a compressor section including a booster or low pressure (LP) compressor 22 and a high pressure (HP) compressor 24; a combustion section 26; a turbine section including a high pressure (HP) turbine 28 and a low pressure (LP) turbine 30; and a jet exhaust nozzle section 32. A high pressure (HP) shaft or spool 34 drivingly connects the HP turbine 28 to the HP compressor 24. A low pressure (LP) shaft or spool 36 drivingly connects the LP turbine 30 to the LP compressor 22.
For the embodiment depicted, the fan section 14 includes a variable pitch fan 38 having a plurality of fan blades 40 coupled to a disk 42 in a spaced apart manner. As depicted, the fan blades 40 extend outwardly from disk 42 generally along the radial direction R. The fan blades 40 and disk 42 are together rotatable about the longitudinal axis 12 in the circumferential direction by LP shaft 36 across a power gear box 44. The power gear box 44 includes a plurality of gears for stepping down the rotational speed of the LP shaft 36 to a more efficient rotational fan speed. Additionally, each fan blade 40 is rotatable relative to the disk 42 about a pitch axis P by virtue of the fan blades 40 being operatively coupled to a suitable actuation member 46. The actuation member 46 is configured to collectively vary the pitch of the fan blades 40 in unison. Further, for the embodiment depicted, the actuation member 46 is also rotatable about the longitudinal axis 12 in the circumferential direction. The actuation member 46 varies the pitch of each fan blade 40 in part by changing its angular position relative to the plurality of blades 40 and LP shaft 36. For example, during operation, at least a portion of the actuation member 46 may temporarily speed up or slow down relative to the plurality of blades 40 and LP shaft 36 to change its angular position relative to the plurality of fan blades 40 and LP shaft 36 and vary the pitch of each of the plurality of blades 40.
Referring still to the exemplary embodiment of
During operation of the turbofan engine 10, a volume of air 58 enters the turbofan 10 through an associated inlet 60 of the nacelle 50 and/or fan section 14. As the volume of air 58 passes across the fan blades 40, a first portion of the air 58 as indicated by arrows 62 is directed or routed into the bypass airflow passage 56 and a second portion of the air 58 as indicated by arrow 64 is directed or routed into the LP compressor 22. The ratio between the first portion of air 62 and the second portion of air 64 is commonly known as a bypass ratio. The pressure of the second portion of air 64 is then increased as it is routed through the high pressure (HP) compressor 24 and into the combustion section 26, where it is mixed with fuel and burned to provide combustion gases 66.
The combustion gases 66 are routed through the HP turbine 28 where a portion of thermal and/or kinetic energy from the combustion gases 66 is extracted via sequential stages of HP turbine stator vanes 68 that are coupled to the outer casing 18 and HP turbine rotor blades 70 that are coupled to the HP shaft or spool 34, thus causing the HP shaft or spool 34 to rotate, thereby supporting operation of the HP compressor 24. The combustion gases 66 are then routed through the LP turbine 30 where a second portion of thermal and kinetic energy is extracted from the combustion gases 66 via sequential stages of LP turbine stator vanes 72 that are coupled to the outer casing 18 and LP turbine rotor blades 74 that are coupled to the LP shaft or spool 36, thus causing the LP shaft or spool 36 to rotate, thereby supporting operation of the LP compressor 22 and/or rotation of the fan 38.
The combustion gases 66 are subsequently routed through the jet exhaust nozzle section 32 of the core turbine engine 16 to provide propulsive thrust. Simultaneously, the pressure of the first portion of air 62 is substantially increased as the first portion of air 62 is routed through the bypass airflow passage 56 before it is exhausted from a fan nozzle exhaust section 76 of the turbofan 10 also providing propulsive thrust. The HP turbine 28, the LP turbine 30, and the jet exhaust nozzle section 32 at least partially define a hot gas path 78 for routing the combustion gases 66 through the core turbine engine 16.
Although not depicted, the operation of the turbofan engine 10 may be monitored by several sensors, such as pressure and/or temperature sensors, detecting various conditions of, e.g., the compressor section, the turbine section, combustion section 26, and/or the ambient environment. Additionally, as will be discussed in greater detail below, the turbofan engine 10 may additionally include a feedback sensor system 100 (see
It should be appreciated, that as used herein, the term “processor” refers not only to integrated circuits referred to in the art as being included in a computer, but also refers to a controller, a microcontroller, a microcomputer, a programmable logic controller (PLC), an application specific integrated circuit, and other programmable circuits. Additionally, the memory device(s) may generally comprise memory element(s) including, but not limited to, computer readable medium (e.g., random access memory (RAM)), computer readable non-volatile medium (e.g., a flash memory), a floppy disk, a compact disc-read only memory (CD-ROM), a magneto-optical disk (MOD), a digital versatile disc (DVD), and/or other suitable memory elements. The memory devices may include software or other control instructions that, when executed by the processor, performs desired functions.
It should be appreciated, that the turbofan engine 10 depicted in
Referring now to
Additionally, an actuation member 46 is positioned inward of the disk 42 and trunnion mechanism 102 of the fan 38 along the radial direction R. The actuation member 46 rotates along with the fan 38 about the centerline 12 in a circumferential direction C (see
Accordingly, for the embodiment depicted, the pitch of each fan blade 40 in the plurality of fan blades 40 may be measured by measuring an angular position of the actuation member 46, or more particularly, the arm 106 of the actuation member 46, relative to the LP shaft 36. The feedback sensor system 100 is included to make such a measurement. More particularly, the feedback sensor system 100 is included to make such a measurement without requiring any holes, slots, opening, etc. in the LP shaft 36 that would provide a sensor with a physical line of sight to the actuation member 46. Accordingly, with such an embodiment, the LP shaft 36 need not be weakened in order to measure the position of the actuation member 46 relative to the LP shaft 36.
Referring now also to
The first and second rings 108, 110 may each be formed of rigid materials having a substantially permanent annular shape and attached within the turbofan engine 10 using any suitable attachment means. For example, one or both of the first and second rings 108, 110 may be formed integrally with a component and the turbofan engine 10, e.g., by welding, or alternatively may be attached to the component within the turbofan engine 10 using one or more suitable mechanical fasteners. Additionally, or alternatively, one or both of the first and second rings 108, 110 may be formed of one or more flexible materials and be given their “ring” or “annular” shape by attachment to the respective component.
Referring now also to
For the embodiment depicted, the one or more first ring features 116 are a plurality of first ring teeth spaced along the surface 114 of the first ring 108 and the one or more second ring features 120 are a plurality of second ring teeth spaced along the surface 118 of the second ring 110. Notably, for the embodiment depicted, each of the first ring teeth and each of the second ring teeth have substantially the same squared geometry (shape). It should be appreciated, however, that in other exemplary embodiments, the one or more first ring features 116 and the one or more second ring features 120 may have any other suitable geometry. Additionally, as used herein, terms of approximation, such as “substantially” or “about,” refer to being within a ten percent (10%) margin of error.
The first ring 108 is a continuous ring about the circumferential direction C, and the second ring 110 is also a continuous ring about the circumferential direction C. The first ring 108 defines a thickness at each of the one or more first ring features 116 that is greater than a thickness between each adjacent first ring 108 feature. Similarly, the second ring 110 defines a thickness at each of the one or more second ring features 120 that is greater than a thickness between each adjacent second ring 110 feature. As used herein, the thickness of the first and second rings 108, 110 refers to a thickness along the sensing axis 122.
The first ring 108 additionally includes a marker 124 having a geometry different than the plurality of first ring features 116. More particularly, for the embodiment depicted, the first ring 108 defines a thickness at the marker 124 that is greater than a thickness through the one or more first ring features 116. It should be understood, however, that in other embodiments, the marker 124 may have any other geometry to distinguish itself from the one or more first ring features 116. As will be discussed below, the marker 124 indicates a new revolution of the first ring 108. Additionally, the marker 124 and the one or more first ring features 116 are evenly spaced along the surface 114 of the first ring 108 about the circumferential direction C. Similarly, the one or more second ring features 120 are also evenly spaced on the surface 118 of the second ring 110 about the circumferential direction C.
Notably, the surface 118 of the second ring 110 has a different number of second ring features 120 than the surface 114 of the first ring 108 has first ring features 116. For example, in the embodiment depicted, the surface 118 of the second ring 110 has six (6) less second ring features 120 than the surface 114 of the first ring 108 has first ring features 116. It should be appreciated, however, that in other exemplary embodiments, the surface 118 of the second ring 110 may have any other suitable number of second ring features 120. For example, in other exemplary embodiments, the surface 118 of the second ring 110 may have at least four (4) less second ring features 120 than the surface 114 of the first ring 108 has first ring features 116, or at least two (2) less second ring features 120 than the surface 114 of the first ring 108 has first ring features 116. Alternatively, however, in other exemplary embodiments, the surface 118 of the second ring 110 may have more second ring features 120 than the surface 114 of the first ring 108 has first ring features 116.
For the embodiment depicted, a first ring feature 116 only overlaps directly with a second ring feature 120 in a few places along the circumferential direction C. Such is a result of the even spacing of the marker 124 and the first ring features 116 on the surface 114 of the first ring 108, the even spacing of the second ring features 120 on the surface 118 of the second ring 110, and the differing number of first ring features 116 and second ring features 120. As stated, for the embodiment depicted, the second ring 110 has six (6) less second ring features 120 than the first ring 108 has first ring features 116. Accordingly, for the embodiment depicted, the first ring features 116 and second ring features 120 overlap directly at six (6) peaks 126 along the circumferential direction C.
Moreover, the feedback sensor system 100 is configured to determine an angular position of the first ring 108 relative to the second ring 110 based on an amount of overlap of the first ring features 116 and the second ring features 120. More particularly, for the embodiment depicted the parameter sensed by the sensor 112, which is influenced by the one or more first ring features 116 and the one or more second ring features 120, is a magnetic flux. The first ring 108, or at least the first ring features 116, may therefore be formed of a ferrous material and the second ring 110, or at least the second ring features 120, may similarly be formed of a ferrous material. Thus, at the peaks 126, where a first ring 108 feature overlaps directly with a second ring 110 feature, an amount of magnetic flux sensed by the sensor 112 is relatively high. By contrast, between peaks 126, where a first ring 108 feature is positioned between adjacent second ring features 120, i.e., a valley 128, the amount of magnetic flux sensed by the sensor 112 is relatively low. Moreover, given the differing geometry of the marker 124 relative to the first ring features 116, the amount of magnetic flux sensed by the sensor 112 when the marker 124 passes under the sensor 112 is even higher than the amount of magnetic flux sensed the sensor 112 at the peaks 126. Such a configuration allows the feedback sensor system 100 to determine a full rotation of the first ring 108. Such a configuration also allows the sensor 112 to determine an angular position of the first ring 108 relative to the second ring 110 based on the sensed position of the marker 124 relative to the sensed peaks 126 and valleys 128.
It should be appreciated, however, that in other exemplary embodiments, the one or more first and second ring features 116, 120 may be magnetized in any other suitable manner. For example, in other exemplary embodiments, one or both of the first and second rings 108, 110 may be configured as electromagnets. Notably, with such a configuration, one or both of the first and second rings 108, 110 may not include features extending proud of a respective surface of the first and second rings 108, 110. For example, the first and second ring features 116, 120 may include, e.g., coils or other wire configurations having an electrical charge, such that one or both of the first and second rings 108, 110 define discrete areas having a magnetic field.
Referring now to
Notably, as previously discussed, the surface 118 of the second ring 110 includes six (6) less second ring features 120 than the surface 114 of the first ring 108 includes first ring features 116. Accordingly, the phase of sensed parameters repeats six (6) times per revolution (i.e., per 360 degrees of rotation). With such a configuration, the feedback sensor system 100 may determine relative angular positions between minus thirty degrees and plus thirty degrees, for a total range of up to sixty degrees. Notably, the actuation member 46 for the exemplary embodiment of
A feedback sensor system in accordance with the present disclosure may therefore more easily sense a position of a first ring relative to a second ring without requiring a direct line of sight to the second ring. Notably, although the exemplary feedback sensor system is depicted being used in conjunction with an actuation member, it should be appreciated that in other embodiments, the exemplary feedback sensor system may instead be used with any other nested components rotatable about the axial direction A wherein it may be difficult to provide a sensor with a direct line of sight to one of such components.
Referring now to
More particularly, for the embodiment depicted, as the second ring 110 moves along the axial direction A relative to the first ring 108, the second ring features 120 will align in a different manner with the first ring features 116. Notably, an axial cross-section of the exemplary embodiment of
The exemplary embodiment of
It should also be appreciated, however, that in still other exemplary embodiments, any other suitable means may be provided for sensing a position of a second ring 110 relative to a first ring 108. For example, in other exemplary embodiments, the parameter sensed by the sensor 112 may not be magnetic flux, and instead may be, e.g., an optical value. For example, in such an exemplary embodiment, the first and second rings 108, 110 may be formed of a transparent or semitransparent material and the one or more first ring features 116 and one or more second ring features 120 may be portions of the first and second rings 108, 110, respectively, more or less transparent than the rest of the first ring 108 and second ring 110. Moreover, in such an exemplary embodiment, a light source may also be positioned within the first ring 108 and second ring 110, and an intensity of light sensed by the sensor 112 (which may be an optical sensor 112) to determine a position of the first ring 108 relative to the second ring 110.
Referring now to
The exemplary method (200) includes at (202) directing a sensor towards the surface of the first ring, and at (204) sensing with the sensor a parameter influenced by the one or more first ring features and the one or more second ring features. For example, in certain exemplary embodiments, the parameter may be a magnetic flux. Moreover, the exemplary method (200) additionally includes at (206) determining a position of the first ring relative to the second ring based on the parameter sensed with the sensor. When the exemplary method (200) is used in conjunction with the feedback sensor system of
Further, in certain exemplary aspects of the method (200) depicted in
A method in accordance with the exemplary aspect depicted in
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
This application claims priority to, and is a divisional application of, U.S. patent application Ser. No. 14/747,114 filed Jun. 23, 2015 which is incorporated by reference in its entirety herein.
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