No-back brake having limited authority damper

Abstract

To provide an improved no-back brake configured to eliminate, minimize, or otherwise reduce chattering.SOLUTION: A main brake assembly (172) is configured to be connected to an actuator and a second portion of a ball ramp mechanism. A limited authority damper assembly is arranged in between a drag brake assembly (170) and the main brake assembly (172). The limited authority damper assembly (174) includes: an outer spacing ring (186) configured to be connected to a drive shaft (162) of the actuator; an inner damping ring connected to the outer spacing ring (186) and the drag brake assembly (170); and a first spring (230) arranged between the outer spacing ring (186) and the inner damping ring (198).SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001]

[0001] Embodiments of the present disclosure relate generally to no-back brake actuators used in conjunction with aircraft control surfaces. [Background technology]

[0002]

[0002] No-back brakes are used in high-lift flap and slat systems on aircraft to maintain wing surfaces in a commanded position. A typical no-back brake includes a drag brake assembly, a main brake assembly, and a ball ramp mechanism. The drag brake assembly and the main brake assembly are typically separated by a spacer configured to transmit axial forces.

[0003]

[0003] No-back brakes are used in conjunction with certain actuators to protect against backdrive during certain load-bearing operations. However, known no-back brakes are susceptible to chattering under such operating conditions. Chattering can cause shudder, audible noise, and relatively large torque oscillations, reducing performance and increasing maintenance costs. Summary of the Invention

[0004]

[0004] There is a need for an improved no-back brake configured to eliminate, minimize, or otherwise reduce chatter. In consideration of these needs, certain embodiments of the present disclosure provide a no-back brake system for an actuator. The no-back brake system includes a ball ramp mechanism. A drag brake assembly is configured to be coupled to a first portion of the ball ramp mechanism. A main brake assembly is configured to be coupled to the actuator and to a second portion of the ball ramp mechanism. A limited authority damper assembly is disposed between the drag brake assembly and the main brake assembly. The limited authority damper assembly includes an outer spacing ring configured to be coupled to a drive shaft of the actuator, an inner damping ring coupled to the outer spacing ring and the drag brake assembly, and a first spring disposed between the outer spacing ring and the inner damping ring.

[0005] In at least one embodiment, the limited authority damper assembly further includes a second spring disposed between the outer spacing ring and the main brake assembly.

[0006]

[0006] The actuator may be a geared rotary actuator configured to control movement of one or more control surfaces of the aircraft.

[0007] In at least one embodiment, the drag brake assembly includes a first plurality of stators and a first plurality of rotors, and the main brake assembly includes a second plurality of stators and a second plurality of rotors.

[0008]

[0008] In at least one embodiment, an outer spacing ring is configured to extend circumferentially around the drive shaft. In at least one embodiment, the outer spacing ring includes a collar and an extension wall extending away from an outer rim of the collar toward the drag brake assembly. An inner damping ring is connected to the extension wall. The inner damping ring is inboard from the extension wall. The inner damping ring is spaced from the drive shaft and configured to extend circumferentially around the drive shaft. The collar can be axially offset from the inner damping ring by a space. A first spring can be disposed within the space.

[0009] In at least one embodiment, a drag brake assembly includes at least one stator having a channel and at least one rotor, wherein a portion of an inner damping ring passes through the channel and abuts the at least one rotor.

[0010] In at least one embodiment, the limited authority damper assembly further includes a retaining ring that secures the inner damping ring to the outer spacing ring.

[0011] Certain embodiments of the present disclosure provide an actuator configured to control movement of one or more control surfaces of an aircraft, the actuator including a drive shaft and a no-back brake system coupled to the drive shaft, as described herein.

[0012]

[0012] Certain embodiments of the present disclosure provide an aircraft including one or more control surfaces and an actuator configured to control movement of the one or more control surfaces as described herein. [Brief description of the drawings]

[0013] [Figure 1]

[0013] An oblique front view of an aircraft according to one embodiment of the present disclosure is shown. [Diagram 2]

[0014] FIG. 1 shows a schematic diagram of a drive system for a wing control surface according to one embodiment of the present disclosure. [Diagram 3]

[0015] FIG. 2 illustrates a perspective interior view of a portion of a wing according to one embodiment of the present disclosure. [Figure 4]

[0016] FIG. 1 illustrates a perspective view of a no-back brake system coupled to a drive shaft of an actuator according to one embodiment of the present disclosure. [Diagram 5]

[0017] FIG. 1 illustrates a perspective cross-sectional view of a no-back brake system coupled to a drive shaft of an actuator. [Figure 6]

[0018] 6 shows a cross-sectional view of the no-back brake system coupled to the drive shaft of the actuator taken along line 6-6 of FIG. 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014]

[0019] The above summary, as well as the following detailed description of certain embodiments, will be better understood when read in conjunction with the accompanying drawings. It is to be understood that, in this specification, an element or step described in the singular following the term "a" or "an" does not necessarily exclude a plurality of elements or steps. Furthermore, references to "one embodiment" are not intended to be interpreted as excluding the existence of additional embodiments that incorporate features described herein. Furthermore, embodiments that "comprising" or "having" one or more elements having a particular condition may include additional elements that do not have such conditions (unless expressly stated otherwise).

[0015]

[0020] Several embodiments of the present disclosure provide a no-back braking system that includes a preloaded, limiting force damper configured to reduce undesirable dynamic interactions such as chatter.

[0016]

[0021] FIG. 1 illustrates a perspective front view of an aircraft 100 according to one embodiment of the disclosure. The aircraft 100 includes a propulsion system 102 including, for example, an engine 104. Optionally, the propulsion system 102 may include more engines 104 than shown. The engines 104 are supported by a wing 106 of the aircraft 100. In other embodiments, the engines 104 may be supported by a fuselage 108 and / or a tail section 110. The tail section 110 may also support a horizontal stabilizer 112 and a vertical stabilizer 114. The fuselage 108 of the aircraft 100 defines an interior cabin 120, which may include a flight deck or cockpit, one or more work sections (e.g., a galley, a crew baggage area, etc.), one or more passenger sections (e.g., first class, business class, and economy class), one or more lavatories, etc. FIG. 1 illustrates an example of the aircraft 100. It is to be understood that aircraft 100 may be sized, shaped, and configured differently than that shown in FIG.

[0017]

[0022] 2 shows a schematic diagram of a drive system 140 for a control surface of a wing 106 according to one embodiment of the disclosure. The control surface includes a flap 142 coupled to a body 144 of the wing 106. The drive system 140 is configured to control the movement of the flap 142 relative to the wing 106. Optionally, the drive system 140 may be used to control the movement of other control surfaces on other portions of the aircraft.

[0018]

[0023] The drive system 140 includes one or more actuators 150 configured to control the movement of the one or more flaps 142. In at least one embodiment, the actuators 150 are geared rotary actuators. As described herein, the actuators 150 include a no-back braking system configured to maintain a commanded position of the flaps 142, slats, etc.

[0019]

[0024] FIG. 3 illustrates a perspective interior view of a portion of a wing 106 according to one embodiment of the present disclosure. An actuator 150, such as a geared rotary actuator, is fixed to a portion of the body 144 of the wing 106. The actuator 150 is coupled to the flap 142 via one or more linkages 152. As described herein, the actuator 150 includes a no-back brake system coupled to a drive shaft. It should be understood that the arrangement shown in FIG. 3 is merely an example. The actuator 150 may be coupled to the flap 142 via a different linkage than is shown. Additionally, the body 144 and the flap 142 may be sized and shaped differently than is shown.

[0020]

[0025] Figure 4 shows a perspective view of a no-back braking system 160 coupled to a drive shaft 162 of an actuator 150 according to one embodiment of the present disclosure. Figure 5 shows a perspective cross-sectional view of a no-back braking system 160 coupled to a drive shaft 162 of an actuator 150. Figure 6 shows a cross-sectional view of a no-back braking system 160 coupled to a drive shaft 162 of an actuator 150 through line 6-6 of Figure 4.

[0021]

[0026] 4-6, in at least one embodiment, the actuator 150 is a geared rotary actuator. A drive shaft 162 includes a peripheral wall 164 that defines a central passageway 166 having an open end 168.

[0022]

[0027] The no-back brake system 160 is fixed about the drive shaft 162. The no-back brake system 160 includes a drag brake assembly 170 separated from a main brake assembly 172 by a limited authority damper assembly 174. The drag brake assembly 170 is proximate an open end 168 of the drive shaft 162, while the main brake assembly 172 is distal from the open end 168. The limited authority damper assembly 174 is disposed between the drag brake assembly 170 and the main brake assembly 172.

[0023]

[0028] Drag brake assembly 170 includes a number of stators 176 splined to a ground path to the actuator housing and a number of rotors 180 splined to drive shaft 162. Drag brake assembly 170 may also include a ball ramp plate 178. Stators 176 and rotors 180 extend circumferentially around drive shaft 162.

[0024]

[0029] The main brake assembly 172 includes a number of stators 182 splined to a ground path to the actuator housing and a number of rotors 184 coupled to the drive shaft 162. The stators 182 and rotors 184 extend circumferentially around the drive shaft 162.

[0025]

[0030] The limited authority damper assembly 174 includes an outer spacing ring 186 attached to the drive shaft 162 at a splined interface 188. The outer spacing ring 186 extends circumferentially around the drive shaft 162. The outer spacing ring 186 includes an annular collar 190 that extends radially away from the drive shaft 162. An annular extending wall 192 extends away from an outer rim 194 of the annular collar 190 toward the drag brake assembly 170. The outer spacing ring 186 may be formed of a metal, such as steel or aluminum. The outer spacing ring 186 acts as a parallel load path used to limit the torque that the limited authority damper assembly 174 can transmit between the drag brake assembly 170 and the main brake assembly 172.

[0026]

[0031] An inner damping ring 198 is connected to an inner edge 200 of the extension wall 192, such as via a splined interface 201. The inner damping ring 198 is inboard (i.e., closer to the drive shaft 162) from the extension wall 192 and extends circumferentially around but is spaced from the drive shaft 162. The inner damping ring 198 may be formed of a metal, such as steel or aluminum.

[0027]

[0032] The inner damping ring 198 has a first surface 204 opposite a second surface 206. The first surface 204 abuts or is close (e.g., within an inch) to a portion of the drag brake assembly 170. In at least one embodiment, the inner stator 176' of the drag brake assembly 170 includes a channel 177. The first surface 204 of the inner damping ring 198 passes through the channel 177 and abuts an inner rotor 180' of the drag brake assembly 170. In at least one embodiment, the first surface 204 of the inner damping ring 198 interacts with the rotor 180' via a friction surface (e.g., a friction coating).

[0028]

[0033] The collar 190 of the outer spacing ring 186 is axially offset from the inner damping ring 198 by a space 250. This allows for a designated axial movement of the inner damping ring 198, such as before the load path of the outer spacing ring 186 is engaged.

[0029]

[0034] An inner retaining ring 210 may be used to secure the inner damping ring 198 to the outer spacing ring 186. Optionally, the limited authority damper assembly 174 may not include the retaining ring 210.

[0030]

[0035] An annular first spring 230, such as an annular Belleville spring or resilient washer, is disposed between the second surface 206 of the inner damping ring 198 and the collar 190 of the outer spacing ring 186. For example, the first spring 230 is disposed within the space 250. The first spring 230 provides damping and has a specified preload. The preloaded first spring 230 is selected to provide a desired amount of torque authority and also provides a parallel load path when the applied axial load is below a predetermined design point. Optionally, the first spring 230 may not be preloaded. Additionally, two or more springs 230 may be used.

[0031]

[0036] An annular second spring 232 (e.g., an adjustment spring), such as an annular Belleville spring or a resilient washer, is disposed between the collar 190 of the outer spacing ring 186 and the main brake assembly 172. The second spring 232 provides damping of the brake section and may have a specified preload. Optionally, the second spring 232 may not be preloaded. In at least one embodiment, the second spring 232 is between the limited authority damper assembly 174 and the main brake assembly 172. An additional spring 233 (such as another adjustment spring) may be disposed on the opposite side of the second spring 232.

[0032]

[0037] Optionally, the second spring 232 may be or may otherwise include an arrangement of two or more annular springs mounted in similar or different orientations, such as stacked in series, stacked in parallel, or in a graduated configuration. Optionally, the system may include a second spring 232. Optionally, the spring 233 may be or may otherwise include an arrangement of two or more annular springs mounted in similar or different orientations, such as stacked in series, stacked in parallel, or in a graduated configuration. Optionally, the system may not include a spring 233.

[0033]

[0038] A ball ramp mechanism 260 is disposed between a flange 262 of the drive shaft 162 and the drag brake assembly 170. The ball ramp mechanism 260 is configured to actuate the main brake assembly 172 when an external load is applied. The main brake assembly 172 acts to hold the moveable structure in place. The drag brake assembly 170 engages the main brake assembly 172, allowing relative movement within the ball ramp mechanism 260.

[0034]

[0039] As described herein, the no-back braking system 160 for the actuator 150 includes a drag brake assembly 170 configured to be coupled to a portion of the ball ramp mechanism 260. The main brake assembly 172 is also configured to be coupled to the drive shaft 162 of the actuator 150. The limited authority damper assembly 174 is disposed between the drag brake assembly 170 and the main brake assembly 172. The limited authority damper assembly 174 includes an outer spacing ring 186 configured to be coupled to the drive shaft 162 of the actuator 150. The inner damping ring 198 is coupled to the outer spacing ring 186 and the drag brake assembly 170. The first spring 230 is disposed between the outer spacing ring 186 and the inner damping ring 198. In at least one embodiment, a second spring 232 is disposed between the outer spacing ring 186 and the main brake assembly 172.

[0035]

[0040] In operation, the parallel load path provided by the outer spacing ring 186 and first spring 230 allows the limited authority damper assembly 174 to provide damping without potential unlocking of the drag and main brake sections. The damper torque may be used as a design point based on the needs of the system, the spring constant, etc.

[0036]

[0041] The limited authority damper assembly 174 creates an interaction between the main brake assembly 172 and the drag brake assembly 170. The outer spacing ring 186 is configured to provide a separate load path, thereby limiting the authority of the limited authority damper assembly 174 or limiting the torque developed by the limited authority damper assembly 174. The first spring 230, the second spring 232 (and spring 233), and the spline connection provide characteristic design points that can be tuned for a particular application.

[0037]

[0042] When an opposing load is applied, the limited authority damper assembly 174 is not engaged. In contrast, during load assist, relative rotation is included within the ball ramp mechanism 260 because the output load is applied to the actuator 150. This relative rotation creates axial motion, engaging the inner damping ring 198 and the main brake assembly 172. The axial motion stops when the holding torque of the main brake assembly 172 equals the output load, thereby creating an equilibrium condition. As the output load increases, the springs 232 and 233 compress based on the axial force balance equation. When the output load reaches a predetermined point, the outer spacing ring 186 engages and transmits the remaining axial force. The damping force of the inner damping ring 198 may be limited to the force provided by the first spring 230 before the outer spacing ring 186 engages.

[0038]

[0043] The limited authority damper assembly 174 operates to stabilize an undesirable dynamic interaction in the no-back brakes known as chatter. This chatter is characterized by large torque oscillations, vibrations, and a loud audible noise on the driveline system. The limited authority damper assembly 174 has been found to significantly reduce chatter. The limited authority damper assembly 174 also reduces performance and safety analysis issues.

[0039]

[0044] Furthermore, the present disclosure includes embodiments according to the following clauses.

[0040]

[0045] Article 1. 1. A no-back braking system for an actuator, comprising: Ball ramp mechanism, a drag brake assembly configured to be coupled to a first portion of the ball ramp mechanism; a main brake assembly configured to be coupled to an actuator and to a second portion of the ball ramp mechanism; and a limited authority damper assembly disposed between the drag brake assembly and the main brake assembly, the limited authority damper assembly comprising: an outer spacing ring configured to be coupled to a drive shaft of the actuator; an inner damping ring coupled to the outer spacing ring and to the drag brake assembly; and A no-back braking system comprising a first spring disposed between the outer spacing ring and the inner damping ring.

[0041]

[0046] Article 2. 2. The no-back braking system of claim 1, wherein the limited authority damper assembly further comprises a second spring disposed between the outer spacing ring and the main brake assembly.

[0042]

[0047] Article 3. 3. The no-back braking system of claim 1 or 2, wherein the actuator is a geared rotary actuator configured to control movement of one or more control surfaces of an aircraft.

[0043]

[0048] Article 4. 4. The no-back brake system of any one of clauses 1 to 3, wherein the drag brake assembly comprises a first plurality of stators and a first plurality of rotors, and the main brake assembly comprises a second plurality of stators and a second plurality of rotors.

[0044]

[0049] Article 5. 5. The no-back braking system of any one of clauses 1 to 4, wherein the outer spacing ring is configured to extend circumferentially around the drive shaft.

[0045]

[0050] Article 6. The outer spacing ring comprises: Color, and 6. The no-back braking system of any one of clauses 1 to 5, comprising an extending wall extending away from the outer rim of the collar towards the drag brake assembly.

[0046]

[0051] Article 7. 7. The no-back braking system of claim 6, wherein the inner damping ring is connected to the extending wall.

[0047]

[0052] Article 8. 8. The no-back braking system of clause 6 or 7, wherein the inner damping ring is inboard from the extending wall, the inner damping ring being spaced from the drive shaft and configured to extend circumferentially around the drive shaft.

[0048]

[0053] Article 9. 9. The no-back braking system of any one of clauses 6 to 8, wherein the collar is axially offset from the inner damping ring by a space.

[0049]

[0054] Article 10. 10. The no-back braking system of claim 9, wherein the first spring is disposed within the space.

[0050]

[0055] Article 11. The drag brake assembly includes: one or more stators having channels; and One or more rotors; 11. The no-back braking system of any one of clauses 1 to 10, wherein a portion of the inner damping ring passes through the channel and abuts the one or more rotors.

[0051]

[0056] Article 12. 12. The no-back braking system of any one of clauses 1 to 11, wherein the limited authority damper assembly further comprises a retaining ring securing the inner damping ring to the outer spacing ring.

[0052]

[0057] Article 13. 1. An actuator configured to control movement of one or more control surfaces of an aircraft, comprising: Drive shaft, and a no-back brake system coupled to the drive shaft, the no-back brake system comprising: Ball ramp mechanism, a drag brake assembly coupled to a first portion of the ball ramp mechanism; a main brake assembly coupled to the actuator and to a second portion of the ball ramp mechanism; and a limited authority damper assembly disposed between the drag brake assembly and the main brake assembly, the limited authority damper assembly comprising: an outer spacing ring coupled to the drive shaft of the actuator, the outer spacing ring extending circumferentially around the drive shaft; an inner damping ring coupled to the outer spacing ring and to the drag brake assembly; and An actuator comprising a first spring disposed between the outer spacing ring and the inner damping ring.

[0053]

[0058] Article 14. Clause 14. The actuator of clause 13, wherein the limited authority damper assembly further comprises a second spring disposed between the outer spacing ring and the main brake assembly.

[0054]

[0059] Article 15. 15. The actuator of clause 13 or 14, wherein the actuator is a geared rotary actuator.

[0055]

[0060] Article 16. The outer spacing ring comprises: a collar axially offset from the inner damping ring by a space, the first spring being disposed within the space; and an extending wall extending away from an outer rim of the collar toward the drag brake assembly; 16. The actuator of any one of clauses 13 to 15, wherein the inner damping ring is connected to the extension wall, the inner damping ring is inboard from the extension wall, the inner damping ring is spaced from the drive shaft and extends circumferentially around the drive shaft.

[0056]

[0061] Article 17. The drag brake assembly includes: one or more stators having channels; and One or more rotors; 17. The actuator of any one of clauses 13 to 16, wherein a portion of the inner damping ring passes through the channel and abuts the one or more rotors.

[0057]

[0062] Article 18. 18. The actuator of any one of clauses 13 to 17, wherein the limited authority damper assembly further comprises a retaining ring securing the inner damping ring to the outer spacing ring.

[0058]

[0063] Article 19. one or more control surfaces; and an actuator configured to control movement of the one or more control surfaces, the actuator comprising: Drive shaft, and a no-back brake system coupled to the drive shaft, the no-back brake system comprising: Ball ramp mechanism, a drag brake assembly coupled to a first portion of the ball ramp mechanism, the drag brake assembly including at least one stator having a channel and at least one rotor; a main brake assembly coupled to the actuator and to a second portion of the ball ramp mechanism; and a limited authority damper assembly disposed between the drag brake assembly and the main brake assembly, the limited authority damper assembly comprising: an outer spacing ring coupled to the drive shaft of the actuator, the outer spacing ring extending circumferentially around the drive shaft; an inner damping ring coupled to the outer spacing ring and to the drag brake assembly, a portion of the inner damping ring passing through the channel and abutting the one or more rotors; a first spring disposed between the outer spacing ring and the inner damping ring; and a second spring disposed between the outer spacing ring and the main brake assembly.

[0059]

[0064] Article 20. The outer spacing ring comprises: a collar axially offset from the inner damping ring by a space, the first spring being disposed within the space; and an extending wall extending away from an outer rim of the collar toward the drag brake assembly; 20. The aircraft described in clause 19, wherein the inner damping ring is connected to the extension wall, the inner damping ring is inboard from the extension wall, the inner damping ring is spaced from the drive shaft and extends circumferentially around the drive shaft.

[0060]

[0065] As described herein, embodiments of the present disclosure provide an improved no-back braking system configured to eliminate, minimize, or otherwise reduce chatter.

[0061]

[0066] For purposes of describing the embodiments of the present disclosure, various spatial and directional terms may be used, such as top, bottom, lower, middle, sideways, horizontal, vertical, front, etc., but it should be understood that such terms are used only with reference to the orientations shown in the drawings, and that these orientations may be flipped, rotated, or otherwise changed so that top becomes bottom, bottom becomes top, horizontal becomes vertical, and so on.

[0062]

[0067] As used herein, a structure, limitation, or element that is "configured to" perform an task or operation is structurally shaped, configured, or adapted to specifically accommodate the task or operation. For clarity and to avoid doubt, an object that is merely capable of being modified to perform an task or operation is not, as used herein, "configured / set up to" perform an task or operation.

[0063]

[0068] It should be understood that the above description is intended to be illustrative, not limiting. For example, the above-described examples (and / or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the various embodiments of the present disclosure without departing from the scope of the present disclosure. The dimensions and types of materials described herein are intended to define aspects of the various embodiments of the present disclosure, but the embodiments are by no means limiting, but are illustrative examples. Many other examples will be apparent to those skilled in the art upon review of the above description. The scope of the various embodiments of the present disclosure should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the accompanying claims and the detailed description herein, the words "including" and "in which" are used as the plain English equivalents of the words "comprising" and "wherein," respectively. Moreover, terms such as "first," "second," and "third" are used merely as labels and are not intended to impose numerical requirements on their objects. Moreover, the limitations of the following claims are not written in means-plus-function form, and are not intended to be construed under 35 U.S.C. § 112(f) unless such claim limitations expressly use the phrase "means for" followed by a statement of function lacking further structure.

[0064]

[0069] The description herein uses examples to disclose various embodiments of the disclosure, including the best mode, and to enable any person skilled in the art to practice various embodiments of the disclosure, including making and using any device or system, and practicing any incorporated methods. The patentable scope of the various examples of the disclosure 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 the examples have structural elements that do not differ from the literal language of the claims, or if the examples include equivalent structural elements that differ only insignificantly from the literal language of the claims.

Claims

1. A no-back braking system (160) for an actuator, comprising: Ball ramp mechanism (260), a drag brake assembly (170) configured to be coupled to a first portion of the ball ramp mechanism (260); a main brake assembly (172) configured to be coupled to an actuator and to a second portion of the ball ramp mechanism (260); a limited authority damper assembly (174) disposed between the drag brake assembly (170) and the main brake assembly (172), the limited authority damper assembly (174) comprising: an outer spacing ring (186) configured to be coupled to a drive shaft (162) of the actuator; an inner damping ring (198) coupled to said outer spacing ring (186) and to said drag brake assembly (170); and The no-back braking system (160) comprises a first spring (230) disposed between the outer spacing ring (186) and the inner damping ring (198).

2. 2. The no-back braking system of claim 1, wherein the limited authority damper assembly further comprises a second spring disposed between the outer spacing ring and the main brake assembly.

3. 2. The no-back braking system of claim 1, wherein the actuator is a geared rotary actuator configured to control movement of one or more control surfaces of an aircraft.

4. 2. The no-back braking system (160) of claim 1, wherein the drag brake assembly (170) comprises a first plurality of stators (176) and a first plurality of rotors (184), and the main brake assembly (172) comprises a second plurality of stators (176) and a second plurality of rotors (184).

5. The no-back braking system (160) of claim 1, wherein the outer spacing ring (186) is configured to extend circumferentially around the drive shaft (162).

6. The outer spacing ring (186) comprises: Collar (190), and The no-back braking system (160) of claim 1, comprising an extending wall (192) extending away from an outer rim of the collar (190) toward the drag brake assembly (170).

7. The no-back braking system (160) of claim 6, wherein the inner damping ring (198) is connected to the extension wall (192).

8. 7. The no-back braking system of claim 6, wherein the inner damping ring is inboard from the extension wall, the inner damping ring being spaced from the drive shaft and configured to extend circumferentially around the drive shaft.

9. The no-back braking system (160) of claim 6, wherein the collar (190) is axially offset from the inner damping ring (198) by a space (250).

10. The no-back braking system (160) of claim 9, wherein the first spring (230) is disposed within the space (250).

11. The drag brake assembly (170) comprises: one or more stators (176) having channels; and one or more rotors (184); The no-back braking system (160) of claim 1, wherein a portion of the inner damping ring (198) passes through the channel and abuts the at least one rotor (184).

12. 2. The no-back braking system (160) of claim 1, wherein the limited authority damper assembly (174) further comprises a retaining ring securing the inner damping ring (198) to the outer spacing ring (186).

13. An actuator configured to control movement of one or more control surfaces of an aircraft (100), comprising: A drive shaft (162), and a no-back brake system (160) coupled to the drive shaft (162), the no-back brake system (160) comprising: Ball ramp mechanism (260), a drag brake assembly (170) coupled to a first portion of the ball ramp mechanism (260); a main brake assembly (172) coupled to the drive shaft (162) of the actuator and to a second portion of the ball ramp mechanism (260); a limited authority damper assembly (174) disposed between the drag brake assembly (170) and the main brake assembly (172), the limited authority damper assembly (174) comprising: an outer spacing ring (186) coupled to the drive shaft (162) of the actuator, the outer spacing ring (186) extending circumferentially around the drive shaft (162); an inner damping ring (198) coupled to said outer spacing ring (186) and to said drag brake assembly (170); and An actuator comprising: a first spring (230) disposed between the outer spacing ring (186) and the inner damping ring (198).

14. 14. The actuator of claim 13, wherein the limited authority damper assembly (174) further comprises a second spring (232) disposed between the outer spacing ring (186) and the main brake assembly (172).

15. The actuator of claim 13 , wherein the actuator is a geared rotary actuator.

16. The outer spacing ring (186) comprises: a collar (190) axially offset from the inner damping ring (198) by a space (250), the first spring (230) being disposed within the space (250); and an extending wall (190) extending from an outer rim of the collar (190) away from the drag brake assembly (170); 14. The actuator of claim 13, wherein the inner damping ring (198) is connected to the extension wall (192), the inner damping ring (198) is inboard from the extension wall (192), and the inner damping ring (198) is spaced from the drive shaft and extends circumferentially around the drive shaft (162).

17. The drag brake assembly (170) comprises: one or more stators (176) having channels; and one or more rotors (184); The actuator of claim 13 , wherein a portion of the inner damping ring (198) passes through the channel and abuts the at least one rotor (184).

18. The actuator of claim 13, wherein the limited authority damper assembly (174) further comprises a retaining ring securing the inner damping ring (198) to the outer spacing ring (186).

19. one or more control surfaces; and and an actuator configured to control movement of the one or more control surfaces, the actuator comprising: A drive shaft (162), and a no-back brake system (160) coupled to the drive shaft (162), the no-back brake system (160) comprising: Ball ramp mechanism (260), a drag brake assembly (170) coupled to a first portion of the ball ramp mechanism (260), the drag brake assembly (170) including at least one stator (176) having a channel and at least one rotor (184); a main brake assembly (172) coupled to the drive shaft (162) of the actuator and to a second portion of the ball ramp mechanism (260); and a limited authority damper assembly (174) disposed between the drag brake assembly and the main brake assembly, the limited authority damper assembly (174) comprising: an outer spacing ring (186) coupled to the drive shaft (162) of the actuator, the outer spacing ring (186) extending circumferentially around the drive shaft (162); an inner damping ring (198) coupled to the outer spacing ring (186) and to the drag brake assembly (170), a portion of the inner damping ring (198) passing through the channel and abutting the one or more rotors (184); a first spring (230) disposed between the outer spacing ring (186) and the inner damping ring (198); and an outer spacing ring disposed between said outer spacing ring and said main brake assembly;

20. The outer spacing ring (186) comprises: a collar (190) axially offset from the inner damping ring (198) by a space (250), the first spring (230) being disposed within the space (250); and an extending wall (192) extending from an outer rim of the collar (190) away from the drag brake assembly (170); 20. The aircraft (100) of claim 19, wherein the inner damping ring (198) is connected to the extension wall (192), the inner damping ring (198) is inboard from the extension wall (192), and the inner damping ring (198) is spaced from and extends circumferentially around the drive shaft (162).

Images