Air turbine starter with disconnector

Abstract

An air turbine starter has a housing, a turbine component positioned within the housing, a drive shaft operably coupled to the turbine component and having an inner portion. An air turbine starter output shaft extends between a first end and a second end, the output shaft movable between a first position in which the first end is coupled to an engine and a second position in which the second end is held within the inner portion and the first end is uncoupled from the engine. A decoupler assembly includes a decoupler for decoupling the output shaft from the engine.

Description

[0001] Cross-references to related applications This application claims priority and benefit to Indian Provisional Patent Application No. 202211029491, filed on May 23, 2022, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This topic generally relates to an air turbine starter, and more specifically, to a disconnector for an air turbine starter. Background Technology

[0003] An aircraft engine (e.g., a gas turbine engine) engages with an air turbine starter during normal operation. The internal components of both the gas turbine engine and the air turbine starter spin together and may both include gearboxes that allow for a gradually decreasing or increasing ratio between successive sections. A reverse drive event can occur when the engine drives the output shaft of the air turbine starter. This reverse drive event can cause the turbine rotor in the air turbine starter to over-spin. Systems and methods for preventing over-spinning of the turbine rotor in an air turbine starter are welcome in the art. Summary of the Invention

[0004] Technical Solution 1. An air turbine starter for starting an engine, the air turbine starter comprising: The housing has an airflow path extending between the inlet and the outlet; A turbine component, located within the housing, having a turbine shaft and a plurality of blades extending from the turbine shaft, wherein at least a portion of the plurality of blades extends into the airflow path; A drive shaft assembly, operably connected to the turbine component, and having an internal portion; An output shaft extending between a first end and a second end, the output shaft being movable between a first position and a second position, wherein in the first position the first end is coupled to the engine, and in the second position the second end is disposed within the internal portion and the first end is separated from the engine; and A disconnector assembly includes a retainer that connects the drive shaft assembly to the output shaft when the output shaft is in the first position, and disconnects the drive shaft assembly from the output shaft when the drive torque transmitted from the drive shaft assembly to the output shaft loads the retainer beyond a torque limit, thereby moving the output shaft to the second position.

[0005] Technical Solution 2. An air turbine starter according to any of the foregoing technical solutions, wherein the retainer is a shear pin, the shear pin extending axially through a portion of the output shaft and a portion of the drive shaft assembly, and wherein the shear pin shears when the overrun torque reaches the torque limit.

[0006] Technical Solution 3. The air turbine starter according to any of the foregoing technical solutions further includes a pin receiver positioned within the output shaft.

[0007] Technical Solution 4. The air turbine starter according to any of the foregoing technical solutions, wherein the output shaft includes a lip at the second end.

[0008] Technical Solution 5. The air turbine starter according to any of the foregoing technical solutions, the air turbine starter further includes a shaft retaining feature disposed within the internal portion, wherein the shaft retaining feature engages the lip to retain the output shaft in the second position.

[0009] Technical Solution 6. The air turbine starter according to any of the foregoing technical solutions, the air turbine starter further includes a hollow shaft disposed within the internal portion, the hollow shaft extending between a closed end and an open end, having a female thread portion defining the internal thread, and wherein the output shaft includes a male thread portion, and the male thread portion and the female thread portion form a threaded connection.

[0010] Technical Solution 7. The air turbine starter according to any of the foregoing technical solutions, the air turbine starter further includes a retainer, the retainer defining at least one engagement surface and having a through hole defining a centerline of the retainer.

[0011] Technical Solution 8. The air turbine starter according to any of the foregoing technical solutions, the air turbine starter further includes a fastener received in the through hole to secure the retainer to the hollow shaft and define the closed end.

[0012] Technical Solution 9. The air turbine starter according to any of the foregoing technical solutions, wherein the hollow shaft further includes an annular recess, and the at least one mating surface of the retainer is received within the recess.

[0013] Technical Solution 10. The air turbine starter according to any of the foregoing technical solutions, the air turbine starter further includes an annular part disposed between the annular recess and the at least one mating surface.

[0014] Technical Solution 11. The air turbine starter according to any of the foregoing technical solutions, wherein the air turbine starter further includes a wave spring, the wave spring being disposed between the base portion of the drive shaft assembly and the hollow shaft.

[0015] Technical Solution 12. The air turbine starter according to any of the foregoing technical solutions, wherein the wave spring preloads at least a portion of the annular recess of the hollow shaft against the annular object.

[0016] Technical Solution 13. A disconnector assembly for disconnecting an output shaft from an engine, comprising: transmission shaft; A hollow shaft having a threaded interior and being at least partially disposed within the drive shaft; An output shaft extending between a first end and a second end, the second end including a threaded exterior operably coupled to the threaded interior of the hollow shaft, the output shaft being axially movable between a first position and a second position; and A retainer that selectively and operably connects the output shaft to the inside of the thread; Specifically, when the driving torque is transmitted from the drive shaft to the output shaft, the retainer is not loaded; when the overrun torque is transmitted below the torque limit, the retainer is loaded; and when the overrun torque reaches the torque limit, the retainer separates the second end of the output shaft from the engine, and the output shaft moves from the first position to the second position.

[0017] Technical Solution 14. The disconnector assembly according to any of the foregoing technical solutions, wherein the retainer is a shear pin, the shear pin extending axially through a portion of the output shaft and a portion of the drive shaft assembly, and wherein the shear pin shears when the overrun torque reaches the torque limit.

[0018] Technical Solution 15. The air turbine starter according to any of the foregoing technical solutions, wherein the output shaft includes a lip at the second end.

[0019] Technical Solution 16. The disconnector assembly according to any of the foregoing technical solutions, the disconnector assembly further includes a shaft retaining feature disposed within the thread, wherein the shaft retaining feature engages the lip to secure the output shaft in the second position.

[0020] Technical Solution 17. The disconnector assembly according to any of the foregoing technical solutions, the disconnector assembly further includes a retainer defining a closed end inside the thread and having at least one engagement surface.

[0021] Technical Solution 18. The disconnector assembly according to any of the foregoing technical solutions, wherein the hollow shaft further includes an annular recess, and the at least one mating surface is received within the annular recess.

[0022] Technical Solution 19. The disconnector assembly according to any of the foregoing technical solutions, the disconnector assembly further includes an annular part disposed between the annular recess and the at least one mating surface.

[0023] Technical Solution 20. The disconnector assembly according to any of the foregoing technical solutions, the disconnector assembly further includes a wave spring disposed at the base portion of the drive shaft assembly to space the hollow shaft from the base portion, and wherein the wave spring preloads at least a portion of the annular recess against the annulus. Attached Figure Description

[0024] In the attached diagram: Figure 1 This is a schematic diagram of a gas turbine engine with an air turbine starter, based on the various aspects described herein.

[0025] Figure 2 This is a cross-sectional view of an air turbine starter according to an aspect of the present disclosure described herein, with the disconnector in a first position.

[0026] Figure 3 For the purposes of this disclosure as described herein, a holder with a [missing information] Figure 2 A magnified view of the disconnector.

[0027] Figure 4 For purposes of this disclosure as described herein, from Figure 3 Perspective view of the retainer.

[0028] Figure 5 For the purposes of this disclosure as described herein, in a second position Figure 2 A cross-sectional view of the disconnector.

[0029] Figure 6 This is a flowchart of a method for operating an air turbine starter according to aspects of the present disclosure described herein. Detailed Implementation

[0030] This disclosure relates to a drive mechanism that generates powered motion in the form of a rotating shaft coupled to a rotating device. A non-limiting example of the drive mechanism may include an air turbine starter that rotatably drives various gears to start a gas turbine engine. The starter has various applications, including starting a gas turbine engine and generating electrical power when the gas turbine engine is in operation. While the exemplary embodiments described herein relate to applications of a gas turbine engine and a starter, embodiments of this disclosure can be applied to any implementation of a drive mechanism that generates rotational motion at a drive output and provides rotational motion to another rotating device.

[0031] The term "exemplary" may be used herein to mean "serving as an example, illustration, or illustration." Any implementation described herein as "exemplary" should not be construed as a preferred or advantageous implementation over others. Furthermore, unless explicitly stated otherwise, all embodiments described herein should be considered exemplary.

[0032] As used in this article, the terms "first," "second," and "third" are used interchangeably to distinguish one component from another and are not intended to indicate the location or importance of an independent component.

[0033] The terms “front” and “rear” are used in this text to refer to relative positions within a gas turbine engine or vehicle, and to the normal operating posture of the gas turbine engine or vehicle. For example, regarding a gas turbine engine, “front” refers to the position closer to the engine inlet, while “rear” refers to the position closer to the engine nozzle or exhaust port.

[0034] As used herein, the term "upstream" can be used to refer to a location opposite to the direction of fluid flow, while the term "downstream" refers to a location in the same direction as the fluid flow. The terms "front" or "front part" mean in front of something, while "back" or "rear part" means behind something. For example, when used in relation to fluid flow, front / front part can mean upstream, while back / rear part can mean downstream.

[0035] Additionally, as used herein, the term "radial" or "radially" refers to a direction away from a common center. For example, in the context of a turbine engine, radial refers to the direction along a ray that extends between the engine's central longitudinal axis and the outer circumference of the engine.

[0036] All directional references (e.g., radial, axial, proximal, distal, up, down, upward, downward, left, right, lateral, front, back, top, bottom, above, below, vertical, horizontal, clockwise, counterclockwise, upstream, downstream, forward, backward, etc.) are used for identification purposes only to aid the reader in understanding this disclosure and do not impose limitations, particularly regarding the location, orientation, or use of aspects of this disclosure described herein. Connecting references (e.g., attachment, connection, link, and linkage) are to be interpreted broadly and may include intermediate structural elements between collections of elements and relative movement between elements, unless otherwise indicated. In this regard, connecting references do not necessarily imply that two elements are directly connected and in a fixed relationship with each other. Exemplary figures are for illustrative purposes only, and the dimensions, positions, order, and relative sizes reflected in the accompanying figures are subject to change.

[0037] The singular forms “a,” “one,” and “the” include plural references unless the context clearly indicates otherwise. Furthermore, as used herein, the terms “group” or “set” can refer to any number of elements, including only one element.

[0038] The approximate language used herein and throughout the specification and claims is applied to modify any quantitative expression that can be permissibly changed without causing a change in the essential function it relates to. Therefore, values ​​modified by one or more terms such as "about," "approximately," "substantially," and "roughly" are not limited to the specified precise values. In at least some instances, approximate language may correspond to the precision of an instrument used to measure a value, or the precision of a method or machine used to construct or manufacture a component and / or system. For example, approximate language may refer to a margin of 1, 2, 4, 5, 10, 15, or 20% with respect to a single value, a range of values(s), and / or the endpoints defining the range of values(s). Scope limitations are combined and / or interchanged herein and throughout the specification and claims, and such scopes are identified and include all subscopes contained therein, unless otherwise indicated by context or language. For example, all scopes disclosed herein include endpoints, and endpoints can be independently combined with each other.

[0039] The term "proximal" as used herein is not restrictive, but rather a descriptive term used to locate the part described herein. Furthermore, the term "proximal" means a part that is closer or closer to the description than a subsequent part. For example, "the first hole proximal to the wall" means that the first hole is closer to the wall, for example, closer to the wall than the second hole.

[0040] Reference Figure 1The diagram illustrates a gas turbine engine 10, which includes a compressor section 12, a combustion section 14, and a turbine section 16. An intake 18, defined by a fan 20, supplies air to the compressor section 12 of the engine 10. The intake 18 and the compressor section 12 are collectively referred to as the 'cold section' 22 of the gas turbine engine 10, which is located upstream of the combustion section 14. The compressor section 12 supplies high-pressure air to the combustion section 14. The high-pressure air is mixed with fuel and burned in a combustion chamber (not shown) in the combustion section 14 to form hot and pressurized combustion gases. The hot and pressurized combustion gases pass through the turbine section 16 before exiting the gas turbine engine 10. As the pressurized gases pass through the high-pressure turbine (not shown) and low-pressure turbine (not shown) of the turbine section 16, the turbine extracts rotational energy from the gas flow passing through the gas turbine engine 10. The compressor section 12 and the turbine section 16 may be shaft-connected to each other to power the compressor section 12. The low-pressure turbine can be powered by a fan 20 connected to the air inlet 18 via a shaft.

[0041] The gas turbine engine 10 may be a turbofan engine commonly used in modern commercial and military aviation, or it may be one of a variety of other known gas turbine engines, such as a turboprop engine or a turboshaft engine. The gas turbine engine 10 may also have an afterburner that burns an additional amount of fuel downstream of the turbine section 16 to increase the velocity of the exhaust gases and thereby increase thrust.

[0042] A starter motor or air turbine starter 100 may be drivenly coupled to the gas turbine engine 10 via an accessory gearbox (AGB) 102, also referred to as a transmission housing, schematically shown as being mounted on the gas turbine engine 10. A horizontal driveshaft 104 may extend from the AGB 102 to the transmission gearbox 106. The AGB 102 may be coupled to a turbine shaft within the gas turbine engine 10, or via a radial driveshaft (not shown) extending from the transmission gearbox 106 into the gas turbine engine 10.

[0043] Now refer to Figure 2 The air turbine starter 100 is shown in more detail below. The air turbine starter 100 may include a turbine housing 108 defining an inlet 110 and an outlet 112. A flow path 114 may extend between the inlet 110 and the outlet 112 for conveying a gas flow from the inlet 110 to the outlet 112. A turbine component 116 may include a turbine shaft 118 and a plurality of blades 120 extending from the turbine shaft 118. The turbine shaft 118 may be journal-connected within the turbine housing 108. The plurality of blades 120 may be disposed within the flow path 114 for rotatably extracting mechanical power from the gas flow along the flow path 114.

[0044] The drive housing 122 may define at least a portion of the gearbox 124. A gear train 126 may be disposed within the gearbox 124 and drivenly coupled to the turbine shaft 118. The gear train 126 may include a ring gear 128 and may also include any gear assembly, including, for example, but not limited to, planetary gear assemblies or pinion assemblies. The turbine shaft 118 may be rotatably mounted to the gear train 126, thereby allowing mechanical power to be transmitted from the turbine component 116 to the gear train 126. The turbine shaft 118 may be supported by a pair of turbine bearings 130.

[0045] The bracket component 131 is drivably coupled to the gear train 126. The disconnector housing 132 may define a drive shaft assembly 135 and includes a drive shaft 134 rotatably mounted to the bracket component 131. An aperture 136 in the bracket component 131 may receive the drive shaft 134. The bracket component 131 may be supported by a bracket bearing 138. The housing interior 140 may contain oil to provide lubrication and cooling to the mechanical parts contained therein, such as the gear train 126, the ring gear 128, and the bearings 130, 138.

[0046] Clutch 142 may be mounted on bracket assembly 131. Disconnector housing 132 is coupled to clutch 142 and is additionally supported by drive bearing 143. Disconnector housing 132 is driven by bracket assembly 131, which in turn is driven by gear train 126, which is in turn driven by turbine assembly 116. Clutch 142 may be any type of shaft coupling portion forming rotor 144, rotor 144 including turbine assembly 116, bracket assembly 131, and disconnector housing 132. Shaft coupling portion may be achieved by any known coupling method, including but not limited to gears, splines, clutch mechanisms, or combinations thereof.

[0047] The output shaft 156 may extend between a first end 164 and a second end 166. During normal operation, the output shaft 156 is in a first position 168, wherein the first end 164 is coupled to the engine 10. By way of a non-limiting example, the output shaft 156 may include a male threaded portion 158 at the second end 166. Furthermore, the output shaft 156 may have a hollow portion 165 that defines a lip 167 at the second end 166.

[0048] Hollow shaft 160 may be disposed within drive shaft assembly 135. Hollow shaft 160 defines an internal portion 154 and extends between a closed end 174 and an open end 176. A second end 166 of output shaft 156 may be received in hollow shaft 160 at open end 176. Output shaft 156 is rotatably disposed (e.g., via threaded connection) within hollow shaft 160 at second end 166. Hollow shaft 152 may be rotatably coupled to drive assembly 135 via spline connection 163. Disconnector housing 132, hollow shaft 152, and output shaft 156 are all rotatable about a single axis of rotation defining a centerline (CL).

[0049] The disconnector assembly 150 may be disposed within at least a portion of the disconnector housing 132. The disconnector assembly 150 may include a threaded interior 152, a portion of the output shaft 156 at the second end 166, and a retainer 170 (see [link to original document]). Figure 3 The internal thread 152 may define at least a portion of the internal portion 154 of the hollow shaft 160. The male threaded portion 158 of the output shaft 156 may be received in the open end 176 of the hollow shaft 160. The internal thread 152 (which is the female threaded portion 162) may be threadedly connected to the male threaded portion 158. The internal thread 152, together with the second end of the output shaft 156 and the retainer 170, may define the disconnector assembly 150.

[0050] The turbine housing 108 and drive housing 122 can be formed by any known materials and methods, including but not limited to die casting of high-strength and lightweight metals such as aluminum, stainless steel, iron, or titanium. The turbine housing 108 and drive housing 122 defining the starter 100 can be formed to a thickness sufficient to provide adequate mechanical rigidity without adding unnecessary weight to the overall assembly (and therefore, the aircraft).

[0051] The rotor 144 can be constructed from any known materials and by any known methods, including but not limited to the extrusion or machining of high-strength metal alloys (such as those containing aluminum, iron, nickel, chromium, titanium, tungsten, vanadium, or molybdenum). The diameters of the turbine shaft 118 and drive shaft 134, together with any other shafts defining the rotor 144, can be fixed or varied along the length of the rotor 144. The diameters can vary to accommodate different sizes and the distance between the rotor and the stator.

[0052] During operation, air is introduced into inlet 110 and travels along airflow path 114, causing the turbine component 116 to rotate. This rotation enables the transmission of mechanical energy through rotor 144 to AGB 102, and subsequently via transmission gearbox 106 (see...). Figure 1 The transmission from the drive shaft 134 to the turbine 10 is transmitted. When the engine 10 is started, the clutch 142 can disconnect the drive shaft 134 from the bracket component 131.

[0053] In reverse drive mode, clutch 142 keeps drive shaft 134 and bracket assembly 131 engaged. A reverse drive event occurs when output shaft 156 drives drive shaft 134. In other words, turbine rotation within gas turbine engine 10 can generate opposite drive torque or reverse drive, which travels through various connections, drive gearbox 106 to horizontal drive shaft 104 to AGB 102, and ultimately via output shaft 156 to air turbine starter 100. In reverse drive events where clutch 142 and bracket assembly 131 cannot maintain the reverse sequence of driven members, it is advantageous to disengage air turbine starter 100 from AGB 102 as quickly as possible. Disconnector assembly 150 achieves a smooth and seamless disconnection from AGB docking portion 146.

[0054] Figure 3 For connection to AGB docking unit 146, in the first position 168, from Figure 2 An enlarged view of the disconnector assembly 150. Under normal operating conditions, normal drive torque (T) is transferred from the output shaft 156 in the first position 168 to AGB102.

[0055] The disconnector assembly 150 may also include a retainer 170. By a non-limiting example, the retainer 170 may be a shear pin 172. The shear pin 172 may extend through the hollow shaft 160 into the output shaft 156. The shear pin 172 has a yield strength based on the material of the shear pin 172 and a cross-sectional area that determines the amount of shear force, for example, by a torque applied to the output shaft 156, which can be applied at the mating portion of the hollow shaft 160 and the output shaft 156. The shear force that the shear pin 172 can withstand may be referred to as its threshold strength.

[0056] Shear pin 172 may have a threshold strength that is greater than that under normal operating conditions (e.g., Figure 3 The intensity occurring under torque T) is less than that under reverse drive (e.g., Figure 5 Torque T in o The strength occurring during reverse drive. The overrun torque (To) during reverse drive is greater than the torque (T) under normal operating conditions. The threshold strength is related to the overrun torque (To) or the reverse drive torque, such that the shear pin 172 remains intact during normal operation and cuts off during a reverse drive event exceeding the predetermined overrun torque (To).

[0057] A pin receiver 148 may be disposed within the output shaft 156. The pin receiver 148 may have a generally "I" shape and be disposed within the output shaft, wherein the elongated "I" portion is aligned with the center line (CL). The end of the "I", together with the elongated "I" portion and the inner wall 157 of the output shaft 156, may define a holding region 159 for at least a portion of the shear pin 172 during a reverse drive event.

[0058] The retainer 178 may define a closed end 174 of the hollow shaft 160, and more specifically, a threaded interior 152. By a non-limiting example, the shaft retaining feature may be a retaining clip 180, which may be secured to the retainer 178. The retaining clip 180 may be annular and include at least one protrusion 182. The hollow shaft 152 may terminate in an annular recess 184. At least a portion of the retainer 178 may be received in the annular recess 184. A circular annulus 185 may be disposed between the annular recess 184 and the retainer 178 to further define the closed end 174.

[0059] Drive shaft assembly 135 may terminate at a base portion 186, spaced from threaded interior 152. A wave spring 188 may be positioned between the base portion 186 and the hollow shaft 160 to axially space the base portion 186 and the hollow shaft 160. The wave spring 188 may be preloaded to secure at least a portion of the hollow shaft 160 against an annular recess 184 and a retainer 178. In other words, the annular recess 185 provides a mating portion between the hollow shaft 160 and the retainer 178. Thus, the wave spring 188 axially aligns the hollow shaft 160 within drive shaft assembly 135, while the annular recess 185 axially and radially aligns the entire hollow shaft 160 via the retainer 178. The base portion 186 may include a recess 190 for receiving at least a portion of the retainer 178. Fasteners (via a non-limiting example, bolt 192) can connect retaining clip 180 to retainer 178 at recess 184 and retainer 178 to drive shaft 134. Nut 194 can be positioned in drive shaft 134 to receive bolt 192 along centerline (CL). Wave spring 188, ring 185, and retainer 178 together provide alignment of output shaft 156 and AGB mating portion 146. Furthermore, this arrangement, together with spline connection 163, provides movement and versatility within disconnector housing 132 to address vibrations during connection, operation, and reverse drive events in which disconnection is necessary.

[0060] Go to Figure 4The image shows an enlarged perspective view of the retainer 178. The retainer 178 defines at least one layer (via non-limiting examples, a first layer 196a, a second layer 196b, and a third layer 196c). A through-hole 195 may be positioned in the center of the retainer 178 and aligned along a centerline (CL) during assembly. At least one layer may unfold from the through-hole 195 to define the retainer 178 having an annular shape. In other words, the retainer may be shaped like a layered cake on its sides. At least one layer 196 may define at least one mating surface 198 (via non-limiting examples, a first mating surface 198a, a second mating surface 198b, and a third mating surface 198c).

[0061] Reference Figure 3 and Figure 4 A first layer 196a may be received in an annular recess 184, and a first engagement surface 198a may be configured to engage with an annulus 185. A second layer 196b may be received in a driveshaft assembly 135, and a second engagement surface 198b may be configured to engage with a base portion 186 of the driveshaft assembly 135. A third layer 196c may be received in a recess 190, and a third engagement surface 198c may be configured to engage with at least a portion of the driveshaft assembly 135. The plurality of engagement surfaces 198 enable the retainer to maintain alignment of the driveshaft assembly 135, the hollow shaft 160, and the output shaft 156.

[0062] Figure 5 This is an enlarged view of the disconnector assembly 150, where the first end 164 of the output shaft 156 is in the second position 199. A lip 167 at the second end 166 of the output shaft 156 engages with a protrusion 182 of the retaining clip 180 to hold the output shaft 156 in the second position 199. The output shaft 156 retracts axially into the threaded interior 152 to disconnect from the AGB mating portion 146. The second or separated position 199 is where the output shaft 156 is disengaged from the AGB mating portion 146 and subsequently from the gas turbine engine 10. The distance (d) between the end of the air turbine starter 100 and the AGB mating portion 146 is smaller than the distance for a typical output shaft for an air turbine starter. The smaller distance (d) reduces the amount of space required to connect the air turbine starter to the AGB 102 and reduces material usage, thereby reducing the overall weight of the air turbine starter 100. In addition, a smaller distance (d) will reduce the total axial envelope of the air turbine starter 100, which helps to provide more design space for other systems surrounding the AGB.

[0063] The lip 167 and the protrusion 182 can be snap-fitted together, preventing the output shaft 156 from retracting and traveling back from the threaded interior 152 toward the AGB mating part 146.

[0064] During operation, when the first end 164 is in the first position 168 and the output shaft 156 is mated with the AGB docking portion 146 (see...) Figure 3 When engaged, the overrun torque (T) of the air turbine starter 100 is below a certain level. o This will cause the shear pin 172 and output shaft 156 to be loaded. The overrun torque (T) at or above a certain level... o This will cause the shear pin 172 and the output shaft 156 to be fully loaded and meet the threshold strength of the shear pin 172. When the predetermined overrun torque level (T) is met... o When the output shaft 156 is disconnected, the shear pin 172 will shear or break to unload the output shaft 156, thereby disengaging the output shaft 156 and causing it to retract into the inner portion 154. The pin receiver 148 may hold the broken portion of the shear pin 172b during the reverse drive event to prevent movement of the shear pin portion 172b into the hollow portion 165 of the output shaft 156. The remaining portion of the shear pin 172a may remain in the holding area 159. Disconnecting the air turbine starter 100 from the gas turbine engine 10 allows the engine 10 to operate at a predetermined overrun torque (T) during the reverse drive event. o It continues to work.

[0065] Method 200 for operating air turbine starter 100 Figure 6 The flowchart is outlined in [the document]. Method 200 includes extracting mechanical power from a gas flow using a turbine component 116 at block 202, which in turn drives a gear train 126 and a clutch 142 (including a drive shaft 134). At block 204, the drive shaft 134 and the threaded interior 152 apply a force (F) to the male threaded portion 158 to rotate the output shaft 156 and to drive a torque (T) (see [the document]). Figure 3 The overrun torque is applied to AGB102. When the overrun torque is transmitted below a certain level, the clutch 142 allows overrun, and the output shaft 156, retainer 170, and female threaded portion 162 are loaded.

[0066] Exceeding torque (T) o The drag torque is caused by the drag torque from the air turbine starter 100. During normal operation, this drag torque comes from the wind resistance from the rotation of the rotor 144, the bearing 138, and the viscous shear from the lubrication in the air turbine starter 100. During a reverse drive event, the overrun torque comes from all bearings 130, 138, and 143 and is amplified by AGB 102. This increase in drag torque causes the shear pin 172 to shear.

[0067] In the reverse drive event, at box 206, when the overrun torque (T) oWhen a certain level is reached, the retainer 170 stops holding, causing the output shaft 156 to spin axially away from AGB102 until it is completely disengaged from AGB102. At frame 208, the output shaft 156 moves into the inner portion 154 and is held in a way that prevents the output shaft 156 from re-engaging to AGB102.

[0068] In addition to the embodiments and configurations shown in the accompanying drawings, many other possible embodiments and configurations are contemplated by this disclosure. Furthermore, the design and placement of various components, such as starters, AGBs, or their components, can be rearranged to enable many different series configurations.

[0069] The embodiments disclosed herein provide a disconnector for disconnecting the output shaft from the AGB and subsequently from the engine at a torque load to prevent reverse drive of the entire air turbine starter. Benefits associated with this disconnection include a reduced risk of a damaged air turbine starter spinning, a risk that could cause further damage if disconnected. By disconnecting, only the retainer needs replacement, and the output shaft is reset. This prevents more expensive replacement parts in the event of additional damage.

[0070] To the extent not described herein, various features and structures of the various embodiments may be combined or substituted with each other as needed. A feature not shown in all embodiments is not to be construed as not being shown, but is done for the sake of brevity. Therefore, various features of different embodiments may be mixed and matched as needed to form new embodiments, regardless of whether the new embodiments are clearly described. All combinations or substitutions of the features described herein are covered by this disclosure.

[0071] This written description uses examples to illustrate the aspects of the disclosure described herein (including the best mode) and also enables those skilled in the art to practice the aspects of this disclosure (including making and using any apparatus or system and performing any incorporated methods). The patentable scope of the aspects of this disclosure is defined by the claims and may include other examples that would occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that are not different from the literal language of the claims, or if they include equivalent structural elements that are not significantly different from the literal language of the claims.

[0072] Other aspects are provided by the subject of the following clauses: An air turbine starter for starting an engine includes a housing having an airflow path extending between an inlet and an outlet; a turbine component positioned within the housing and having a turbine shaft and a plurality of blades extending from the turbine shaft, wherein at least a portion of the plurality of blades extends into the airflow path; a drive shaft assembly operatively coupled to the turbine component and having an internal portion; an output shaft extending between a first end and a second end, the output shaft being movable between a first position and a second position, in the first position being coupled to the engine, and in the second position being disposed within the internal portion and the first end being disengaged from the engine; and a disconnector assembly including a retainer that, when the output shaft is in the first position, connects the drive shaft assembly to the output shaft, and when a drive torque transmitted from the drive shaft assembly to the output shaft loads the retainer to an extent exceeding a torque limit, the retainer disconnects the drive shaft assembly from the output shaft, thereby moving the output shaft to the second position.

[0073] An air turbine starter according to any of the foregoing provisions, wherein the retainer is a shear pin that extends axially through a portion of the output shaft and a portion of the drive shaft assembly, and wherein the shear pin shears when the overrun torque reaches the torque limit.

[0074] The air turbine starter according to any of the foregoing clauses further includes a pin receiver located within the output shaft.

[0075] An air turbine starter according to any of the foregoing terms, wherein the output shaft includes a lip at the second end.

[0076] The air turbine starter according to any of the foregoing provisions further includes a shaft retaining feature disposed within the inner portion, wherein the shaft retaining feature engages the lip to retain the output shaft in the second position.

[0077] According to any of the foregoing provisions, the air turbine starter further includes a hollow shaft disposed within the inner portion, the hollow shaft extending between a closed end and an open end, having a female threaded portion defining a threaded interior, and wherein the output shaft includes a male threaded portion, and the male threaded portion and the female threaded portion form a threaded connection.

[0078] The air turbine starter according to any of the foregoing provisions further includes a retainer that defines at least one engagement surface and has a through hole defining a centerline of the retainer.

[0079] The air turbine starter according to any of the foregoing provisions further includes a fastener received within the through hole to secure the retainer to the hollow shaft and define the closed end.

[0080] According to any of the foregoing provisions, the air turbine starter, wherein the hollow shaft further includes an annular recess, and the at least one engagement surface of the retainer is received within the recess.

[0081] The air turbine starter according to any of the foregoing provisions further includes an annulus disposed between the annular recess and the at least one mating surface.

[0082] The air turbine starter according to any of the foregoing provisions further includes a wave spring disposed between the base portion of the drive shaft assembly and the hollow shaft.

[0083] According to any of the foregoing provisions, in an air turbine starter, the wave spring preloads at least a portion of the annular recess of the hollow shaft against the annulus.

[0084] A disconnector assembly for disconnecting an output shaft from an engine includes: a drive shaft; a hollow shaft having a threaded interior and at least partially disposed within the drive shaft; an output shaft extending between a first end and a second end, the second end including a threaded exterior operably coupled to the threaded interior of the hollow shaft, the output shaft being axially movable between a first position and a second position; and a retainer selectively and operably coupled to the threaded interior of the output shaft; wherein the retainer is not loaded when a drive torque is transmitted from the drive shaft to the output shaft, the retainer is loaded when an overshoot torque is transmitted below a torque limit, and when the overshoot torque reaches the torque limit, the retainer separates the second end of the output shaft from the engine, and the output shaft moves from the first position to the second position.

[0085] According to any of the foregoing provisions, the retainer is a shear pin that extends axially through a portion of the output shaft and a portion of the drive shaft assembly, and wherein the shear pin shears when the overrun torque reaches the torque limit.

[0086] An air turbine starter according to any of the foregoing terms, wherein the output shaft includes a lip at the second end.

[0087] The disconnector assembly according to any of the foregoing provisions further includes a shaft retaining feature disposed within the thread, wherein the shaft retaining feature engages the lip to secure the output shaft in the second position.

[0088] The disconnector assembly according to any of the foregoing provisions further includes a retainer that defines a closed end inside the thread and has at least one engagement surface.

[0089] According to any of the foregoing provisions, the disconnector assembly, wherein the hollow shaft further includes an annular recess, and the at least one engagement surface is received within the annular recess.

[0090] The disconnector assembly according to any of the foregoing provisions further includes an annulus disposed between the annular recess and the at least one engagement surface.

[0091] The disconnector assembly according to any of the foregoing provisions further includes a wave spring disposed at the base portion of the drive shaft assembly to space the hollow shaft from the base portion, wherein the wave spring preloads at least a portion of the annular recess against the annulus.

Claims

1. An air turbine starter for starting an engine, the air turbine starter comprising: The housing has an airflow path extending between the inlet and the outlet; A turbine component, located within the housing, having a turbine shaft and a plurality of blades extending from the turbine shaft, wherein at least a portion of the plurality of blades extends into the airflow path; A drive shaft assembly, operably connected to the turbine component, and having an internal portion; An output shaft extending between a first end and a second end, the output shaft being movable between a first position and a second position, wherein in the first position the first end is coupled to the engine, and in the second position the second end is disposed within the internal portion and the first end is separated from the engine; as well as A disconnector assembly includes a retainer that, when the output shaft is in the first position, connects the drive shaft assembly to the output shaft, and when the drive torque transmitted from the drive shaft assembly to the output shaft loads the retainer beyond a torque limit, the retainer disconnects the drive shaft assembly from the output shaft, thereby moving the output shaft to the second position. The air turbine starter further includes a hollow shaft disposed within the internal portion, the hollow shaft extending between a closed end and an open end, having a female threaded portion defining the internal thread, and wherein the output shaft includes a male threaded portion, and the male threaded portion and the female threaded portion form a threaded connection. as well as The air turbine starter also includes a retainer that defines at least one engagement surface and has a through hole defining a centerline of the retainer.

2. The air turbine starter according to claim 1, wherein, The retainer is a shear pin that extends axially through a portion of the output shaft and a portion of the drive shaft assembly, wherein the shear pin shears when the overrun torque reaches the torque limit.

3. The air turbine starter according to claim 1, wherein the air turbine starter further comprises a pin receiver positioned within the output shaft.

4. The air turbine starter according to claim 1, wherein, The output shaft includes a lip at the second end.

5. The air turbine starter of claim 4, further comprising a shaft retaining feature disposed within the inner portion, wherein the shaft retaining feature engages the lip to retain the output shaft in the second position.

6. The air turbine starter of claim 1, further comprising a fastener received within the through hole to secure the retainer to the hollow shaft and define the closed end.

7. The air turbine starter according to claim 6, wherein, The hollow shaft also includes an annular recess, and the at least one engagement surface of the retainer is received within the recess.

8. The air turbine starter according to claim 7, further comprising an annular portion disposed between the annular recess and the at least one mating surface.

9. The air turbine starter according to claim 8, further comprising a wave spring disposed between the base portion of the drive shaft assembly and the hollow shaft.

10. The air turbine starter according to claim 9, wherein, The wave spring preloads at least a portion of the annular recess of the hollow shaft against the annular object.

11. A disconnector assembly for disconnecting an output shaft from an engine, comprising: transmission shaft; A hollow shaft having a threaded interior and being at least partially disposed within the drive shaft; An output shaft extending between a first end and a second end, the second end including a threaded exterior operably connected to the threaded interior of the hollow shaft, the output shaft being axially movable between a first position and a second position; as well as A retainer that selectively and operably connects the output shaft to the inside of the thread; Specifically, when the driving torque is transmitted from the drive shaft to the output shaft, the retainer is not loaded; when the overrun torque is transmitted below the torque limit, the retainer is loaded; and when the overrun torque reaches the torque limit, the retainer separates the second end of the output shaft from the engine, and the output shaft moves from the first position to the second position. as well as The disconnector assembly also includes a retainer that defines a closed end inside the thread and has at least one engagement surface.

12. The disconnector assembly of claim 11, wherein, The retainer is a shear pin that extends axially through a portion of the output shaft and a portion of the drive shaft, wherein the shear pin shears when the overrun torque reaches the torque limit.

13. The disconnector assembly of claim 12, wherein, The output shaft includes a lip at the second end.

14. The disconnector assembly of claim 13, further comprising a shaft retaining feature disposed within the thread, wherein the shaft retaining feature engages the lip to secure the output shaft in the second position.

15. The disconnector assembly of claim 11, wherein, The hollow shaft further includes an annular recess, and the at least one mating surface is received within the annular recess.

16. The disconnector assembly of claim 15, further comprising an annulus disposed between the annular recess and the at least one engagement surface.

17. The disconnector assembly of claim 16, further comprising a wave spring disposed at the base portion of the drive shaft assembly to space the hollow shaft from the base portion, wherein, The wave spring preloads at least a portion of the annular recess against the annular object.

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