阅读说明：本技术 用于致动器的行进指状物锁 (Travel finger lock for actuator ) 是由 J·T·科佩切克 于 2020-02-26 设计创作，主要内容包括：一种线性致动器锁装置(500)包括：壳体(410),所述壳体(410)具有限定轴向腔体(504)的内表面(502),所述壳体(410)包括其中所述轴向腔体具有第一横向尺寸的第一壳体部分(506)、其中所述轴向腔体具有大于所述第一横向尺寸的第二横向尺寸的第二壳体部分(508)以及从所述第一壳体部分到所述第二壳体部分的面(510)；活塞(414),所述活塞(414)被配置成用于在所述轴向腔体内的轴向移动；锁指状物(540),所述锁指状物(540)附连到所述活塞并且远离所述活塞延伸,其中指状物端部(544)被配置成在延伸时接触所述面(510)并且在缩回时配合在所述第一壳体部分内；以及套筒(550),所述套筒(550)被配置成在其中准许所述锁指状物延伸的位置与被配置成接触并缩回所述锁指状物的位置之间移动。(A linear actuator lock arrangement (500) comprising: a housing (410), the housing (410) having an inner surface (502) defining an axial cavity (504), the housing (410) including a first housing portion (506) in which the axial cavity has a first transverse dimension, a second housing portion (508) in which the axial cavity has a second transverse dimension greater than the first transverse dimension, and a face (510) from the first housing portion to the second housing portion; a piston (414), the piston (414) configured for axial movement within the axial cavity; a lock finger (540) attached to the piston and extending away from the piston, wherein a finger end (544) is configured to contact the face (510) when extended and fit within the first housing portion when retracted; and a sleeve (550), the sleeve (550) configured to move between a position in which the lock finger is permitted to extend and a position configured to contact and retract the lock finger.)

1. A linear actuator lock device comprising:

a housing having an inner surface defining an axial cavity, the housing comprising:

a first housing portion, wherein the axial cavity has a first transverse dimension;

a second housing portion, wherein the axial cavity has a second transverse dimension that is greater than the first transverse dimension; and

a face defined by the inner surface from the first housing portion to the second housing portion;

a piston having a first piston end and a second piston end axially opposite the first piston end, wherein the piston is configured for axial movement within the axial cavity between a first piston position and a second piston position;

a lock finger attached to the first piston end at a first finger end and extending away from the piston to a second finger end, wherein the second finger end is configured to contact the face in an extended configuration and fit within the first housing portion in a retracted configuration; and

a sleeve disposed within the second housing portion and configured to move axially within the second housing portion between a first sleeve position in which the lock fingers are permitted to extend to the extended configuration and a second sleeve position configured to contact the lock fingers and urge the lock fingers to the retracted configuration.

2. The device of claim 1, wherein the second finger end is configured to axially contact the face and axially contact the piston in the extended configuration.

3. The device of claim 1 or 2, wherein the lock finger is configured to prevent movement of the piston toward the second piston position in the extended configuration and to permit movement of the piston toward the second piston position in the retracted configuration.

4. The device of any one of claims 1 to 3, further comprising a biasing member configured to bias the lock finger away from the retracted configuration and towards the extended configuration.

5. The device of any one of claims 1 to 4, wherein the sleeve defines an axial bore and the first piston end is configured to extend at least partially within the axial bore in the second sleeve position.

6. The device of any one of claims 1 to 5, further comprising a first seal arranged in sealing contact with the inner surface and an outer surface of the sleeve, and a second seal arranged in sealing contact with the inner surface and the outer surface of the sleeve, wherein the inner surface, the face, the outer surface, the first seal, and the second seal define a pressure chamber.

7. The device of any one of claims 1 to 6, further comprising a biasing member configured to urge the sleeve towards the first sleeve position.

8. The device of any one of claims 1 to 7, further comprising a pressure chamber defined at least in part by the inner surface, the piston, and a piston seal arranged in sealing contact with the piston and the inner surface.

9. The apparatus of claim 8, wherein the piston is configured to be urged from the first piston position toward the second piston position by fluid pressure provided within the pressure chamber.

10. The device of claim 9, wherein the sleeve is configured to be urged from the first sleeve position toward the second sleeve position by fluid pressure provided within the pressure chamber.

11. The apparatus of any one of claims 1 to 10, wherein the housing is configured to be attached to an aircraft structure and the second piston end is configured to be attached to a movable aircraft component.

12. A method of locking a linear actuator, the method comprising:

urging axial movement of a piston away from a first piston position and toward a second piston position within an axial cavity defined by an inner surface of a housing, wherein the piston has a first piston end and a second piston end axially opposite the first piston end;

pushing an axial movement of a lock finger by the piston, the lock finger attached to a first piston end at a first finger end and extending away from the piston to a second finger end in an extended configuration;

contacting a face defined by the inner surface between a first housing portion in which the axial cavity has a first transverse dimension to a second housing portion in which the axial cavity has a second transverse dimension greater than the first transverse dimension with the second finger end;

preventing movement of the piston to the second piston position by the contact;

movement of an axially urging sleeve within said axial cavity from a first sleeve position to a second sleeve position;

contacting the lock finger through the sleeve;

urging the lock finger through the sleeve from the extended configuration to a retracted configuration in which the lock finger fits within the first housing portion; and

moving the piston to the second piston position.

13. The method of claim 12, wherein urging axial movement of the piston away from the first piston position toward the second piston position within the axial cavity defined by the inner surface of the housing further comprises applying fluid pressure to a pressure chamber defined at least in part by the inner surface, the piston, and a piston seal arranged in sealing contact with the piston and the inner surface.

14. The method of claim 12 or 13, wherein axially urging movement of the sleeve within the axial cavity from the second sleeve position to the first sleeve position further comprises urging movement of the sleeve via a spring bias.

15. The method of any of claims 12 to 14, further comprising:

axially urging movement of the sleeve within the axial cavity from the second sleeve position to the first sleeve position;

urging the piston away from the second piston position to the first piston position;

passing the second finger end out of the first housing portion, past the face, and into the second housing portion; and

extending the lock finger away from the piston from the retracted configuration to the extended configuration.

16. The method of claim 15, wherein extending the lock finger away from the piston from the retracted configuration to the extended configuration further comprises extending the lock finger away from the piston from the retracted configuration to the extended configuration with a biasing member.

17. The method of claim 15 or 16, wherein axially urging the sleeve to move within the axial cavity from the second sleeve position to the first sleeve position further comprises applying fluid pressure to a pressure chamber defined by the inner surface, an outer surface of the sleeve, a first seal arranged in sealing contact with the inner surface and the outer surface of the sleeve, and a second seal arranged in sealing contact with the inner surface and the outer surface of the sleeve.

18. The method of any of claims 15 to 17, wherein axially urging movement of the sleeve from the second sleeve position to the first sleeve position within the axial cavity further comprises urging movement of the sleeve by a biasing member configured to axially urge movement of the sleeve from the second sleeve position to the first sleeve position.

19. The method of any of claims 12 to 18, wherein preventing movement of the piston to the second piston position by the contact further comprises:

contacting a second face defined by the piston with the second finger end; and

transmitting the axial force of the piston to the housing through the second finger end.

20. A thrust reverser actuator system comprising:

a fuselage structure;

a thrust reverser cover configured to move relative to the fuselage structure;

a linear actuator configured to move the thrust reverser cowl relative to the fuselage structure and comprising:

a housing having an inner surface defining an axial cavity, the housing comprising:

a first housing portion, wherein the axial cavity has a first transverse dimension;

a second housing portion, wherein the axial cavity has a second transverse dimension that is greater than the first transverse dimension; and

a face defined by the inner surface from the first housing portion to the second housing portion;

a piston having a first piston end and a second piston end axially opposite the first piston end, wherein the piston is configured for axial movement within the axial cavity between a first piston position and a second piston position; and

a lock device, the lock device comprising:

a lock finger attached to the first piston end at a first finger end and extending away from the piston to a second finger end, wherein the second finger end is configured to contact the face in an extended configuration and fit within the first housing portion in a retracted configuration; and

a sleeve disposed within the second housing portion and configured to move axially within the second housing portion between a first sleeve position in which the lock fingers are permitted to extend to the extended configuration and a second sleeve position configured to contact the lock fingers and urge the lock fingers to the retracted configuration.

21. The system of claim 20, wherein the lock finger is configured to prevent movement of the piston toward the second piston position in the extended configuration and to permit movement of the piston toward the second piston position in the retracted configuration.

22. The system of claim 20 or 21, further comprising a pressure chamber defined at least in part by the inner surface, the piston, and a piston seal arranged in sealing contact with the piston and the inner surface, wherein the piston is configured to be urged from the first piston position toward the second piston position by fluid pressure provided within the pressure chamber.

Technical Field

The present description relates to an aircraft engine thrust reverser lock.

Background

Contemporary aircraft engines may include thrust reversal actuation systems to help reduce aircraft speed during landing. Typical thrust reversers include a movable transition cowl (transcowl) that, when in an activated position, reverses at least a portion of the airflow through the engine.

Accidental or unintentional activation and deployment of thrust reversers at inappropriate times can be dangerous or fatal. Accidental deployment of ground crew while performing maintenance on the engine may result in injury or death. Accidental activation during flight can result in catastrophic airspeed loss or fuselage failure. Mechanical faults (e.g., hydraulic losses) may also allow the reverser to move out of the stowed position at an inappropriate time.

To prevent accidental or unintentional thrust reverser deployment, a locking mechanism is used. The lock must first be disengaged before the thrust reverser can be moved from its stowed position. Some current reverser lock designs implement rotating jaws to engage the probe. Such designs can be heavy and mechanically complex, which increases the weight and maintenance requirements of the aircraft on which they are installed.

Disclosure of Invention

Generally, this document describes an aircraft engine thrust reverser lock.

In a first aspect, a linear actuator lock device includes: a housing having an inner surface defining an axial cavity, the housing comprising a first housing portion wherein the axial cavity has a first transverse dimension, a second housing portion wherein the axial cavity has a second transverse dimension greater than the first transverse dimension, and a face defined by the inner surface from the first housing portion to the second housing portion; a piston having a first piston end and a second piston end axially opposite the first piston end, wherein the piston is configured for axial movement within the axial cavity between a first piston position and a second piston position; a lock finger attached to the first piston end at a first finger end and extending away from the piston to a second finger end, wherein the second finger end is configured to contact the face in an extended configuration and fit within the first housing portion in a retracted configuration; and a sleeve disposed within the second housing portion and configured to move axially within the second housing portion between a first sleeve position in which the lock finger is permitted to extend to the extended configuration and a second sleeve position configured to contact the lock finger and urge the lock finger to the retracted configuration.

In a second aspect according to aspect 1, the second finger end is configured to axially contact the face and axially contact the piston in the extended configuration.

In a third aspect according to any one of aspects 1 to 2, the lock finger is configured to prevent movement of the piston towards the second piston position in the extended configuration and to permit movement of the piston towards the second piston position in the retracted configuration.

In a fourth aspect according to any one of aspects 1 to 3, the device further comprises a biasing member configured to bias the lock finger away from the retracted configuration and towards the extended configuration.

In a fifth aspect according to any one of aspects 1 to 4, the sleeve defines an axial bore and the first piston end is configured to extend at least partially within the axial bore in the second sleeve position.

In a sixth aspect according to any one of aspects 1 to 5, the device further comprises a first seal arranged in sealing contact with the inner surface and an outer surface of the sleeve, and a second seal arranged in sealing contact with the inner surface and the outer surface of the sleeve, wherein the inner surface, the face, the outer surface, the first seal and the second seal define a pressure chamber.

In a seventh aspect according to any one of aspects 1 to 6, the device further comprises a biasing member configured to urge the sleeve towards the first sleeve position.

In an eighth aspect according to any one of aspects 1 to 7, the device further comprises a pressure chamber at least partially defined by the inner surface, the piston, and a piston seal arranged in sealing contact with the piston and the inner surface.

In a ninth aspect according to aspect 8, the piston is configured to be urged from the first piston position toward the second piston position by fluid pressure provided within the pressure chamber.

In a tenth aspect according to aspect 9, the sleeve is configured to be urged from the first sleeve position towards the second sleeve position by fluid pressure provided within the pressure chamber.

In an eleventh aspect according to any one of aspects 1 to 10, the housing is configured to be attached to an aircraft structure and the second piston end is configured to be attached to a movable aircraft component.

In a twelfth aspect, a method of locking a linear actuator, the method comprising: urging axial movement of a piston away from a first piston position and toward a second piston position within an axial cavity defined by an inner surface of a housing, wherein the piston has a first piston end and a second piston end axially opposite the first piston end; pushing an axial movement of a lock finger by the piston, the lock finger attached to a first piston end at a first finger end and extending away from the piston to a second finger end in an extended configuration; contacting, by the second finger end, a face defined by the inner surface between a first housing portion in which the axial cavity has a first transverse dimension to a second housing portion in which the axial cavity has a second transverse dimension that is greater than the first transverse dimension; preventing movement of the piston to the second piston position by the contact; movement of an axially urging sleeve within said axial cavity from a first sleeve position to a second sleeve position; contacting the lock finger through the sleeve; urging the lock finger through the sleeve from the extended configuration to a retracted configuration in which the lock finger fits within the first housing portion; and moving the piston to the second piston position.

In a thirteenth aspect according to aspect 12, urging axial movement of the piston away from the first piston position toward the second piston position within the axial cavity defined by the inner surface of the housing further comprises applying fluid pressure to a pressure chamber defined at least in part by the inner surface, the piston, and a piston seal arranged in sealing contact with the piston and the inner surface.

In a fourteenth aspect according to aspects 12 or 13, axially urging movement of the sleeve within the axial cavity from the second sleeve position to the first sleeve position further comprises urging movement of the sleeve by a spring bias.

In a fifteenth aspect according to any one of aspects 12 to 14, the method further comprises: axially urging movement of the sleeve within the axial cavity from the second sleeve position to the first sleeve position; urging the piston away from the second piston position to the first piston position; passing the second finger end out of the first housing portion, past the face, and into the second housing portion; and extending the lock finger away from the piston from the retracted configuration to the extended configuration.

In a sixteenth aspect according to aspect 15, extending the lock finger away from the piston from the retracted configuration to the extended configuration further comprises extending the lock finger away from the piston from the retracted configuration to the extended configuration with a biasing member.

In a seventeenth aspect according to aspects 15 or 16, axially urging movement of the sleeve from the second sleeve position to the first sleeve position within the axial cavity further comprises applying fluid pressure to a pressure chamber defined by the inner surface, an outer surface of the sleeve, a first seal arranged in sealing contact with the inner surface and the outer surface of the sleeve, and a second seal arranged in sealing contact with the inner surface and the outer surface of the sleeve.

In an eighteenth aspect according to any one of aspects 15 to 17, axially urging movement of the sleeve within the axial cavity from the second sleeve position to the first sleeve position further comprises urging movement of the sleeve by a biasing member configured to axially urge movement of the sleeve from the second sleeve position to the first sleeve position.

In a nineteenth aspect according to any one of aspects 12 to 18, preventing movement of the piston to the second piston position by the contact further comprises: contacting a second face defined by the piston with the second finger end; and transmitting the axial force of the piston to the housing through the second finger end.

In a twentieth aspect, a thrust reverser actuator system includes a body structure, a thrust reverser cowl configured to move relative to the body structure, a linear actuator configured to move the thrust reverser cowl relative to the body structure, and a lock device, and includes: a housing having an inner surface defining an axial cavity, the housing comprising a first housing portion wherein the axial cavity has a first transverse dimension, a second housing portion wherein the axial cavity has a second transverse dimension greater than the first transverse dimension, and a face defined by the inner surface from the first housing portion to the second housing portion; a piston having a first piston end and a second piston end axially opposite the first piston end, wherein the piston is configured for axial movement within the axial cavity between a first piston position and a second piston position. The lock device includes: a lock finger attached to the first piston end at a first finger end and extending away from the piston to a second finger end, wherein the second finger end is configured to contact the face in an extended configuration and fit within the first housing portion in a retracted configuration; and a sleeve disposed within the second housing portion and configured to move axially within the second housing portion between a first sleeve position in which the lock finger is permitted to extend to the extended configuration and a second sleeve position configured to contact the lock finger and urge the lock finger to the retracted configuration.

In a twenty-first aspect according to aspect 20, the lock finger is configured to prevent movement of the piston toward the second piston position in the extended configuration and to permit movement of the piston toward the second piston position in the retracted configuration.

In a twenty-second aspect according to aspects 20 or 21, the system further comprises a pressure chamber at least partially defined by the inner surface, the piston, and a piston seal arranged in sealing contact with the piston and the inner surface, wherein the piston is configured to be urged from the first piston position towards the second piston position by fluid pressure provided within the pressure chamber.

A system of one or more computers can be configured to perform particular operations or actions by installing software, firmware, hardware, or a combination thereof on the system that in operation causes the system to perform the actions. One or more computer programs may be configured to implement particular operations or actions by including instructions that, when executed by a data processing apparatus, cause the apparatus to implement the actions.

One general aspect includes a linear actuator lock device comprising: a housing having an inner surface defining an axial cavity, the housing comprising a first housing portion wherein the axial cavity has a first transverse dimension, a second housing portion wherein the axial cavity has a second transverse dimension greater than the first transverse dimension, and a face defined by the inner surface from the first housing portion to the second housing portion; a piston having a first piston end and a second piston end axially opposite the first piston end, wherein the piston is configured for axial movement within the axial cavity between a first piston position and a second piston position; a lock finger attached to the first piston end at a first finger end and extending away from the piston to a second finger end, wherein the second finger end is configured to contact the face in an extended configuration and fit within the first housing portion in a retracted configuration; and a sleeve disposed within the second housing portion and configured to move axially within the second housing portion between a first sleeve position in which the lock finger is permitted to extend to the extended configuration and a second sleeve position configured to contact the lock finger and urge the lock finger to the retracted configuration. Other embodiments of this aspect include corresponding computer systems, apparatus, and computer programs recorded on one or more computer storage devices, each configured to implement the actions of the methods.

Implementations may include one or more of the following features. The device, wherein the second finger end may be configured to axially contact the face and axially contact the piston in the extended configuration. The device, wherein the lock finger may be configured to prevent movement of the piston toward the second piston position in the extended configuration and to permit movement of the piston toward the second piston position in the retracted configuration. The device may further comprise a biasing member configured to bias the lock finger away from the retracted configuration and towards the extended configuration. The sleeve may define an axial bore, and the first piston end may be configured to extend at least partially within the axial bore in the second sleeve position. The apparatus may include a first seal arranged in sealing contact with the inner surface and an outer surface of the sleeve, and a second seal arranged in sealing contact with the inner surface and the outer surface of the sleeve, wherein the inner surface, the face, the outer surface, the first seal, and the second seal define a pressure chamber. The device may include a biasing member configured to urge the sleeve towards the first sleeve position. The device may include a pressure chamber at least partially defined by the inner surface, the piston, and a piston seal disposed in sealing contact with the piston and the inner surface. The device, wherein the piston may be configured to be urged from the first piston position towards the second piston position by fluid pressure provided within the pressure chamber. The device, wherein the sleeve may be configured to be urged from the first sleeve position towards the second sleeve position by fluid pressure provided within the pressure chamber. The apparatus, wherein the housing may be configured to be attached to an aircraft structure and the second piston end is configured to be attached to a movable aircraft component. Implementations of the described technology may include hardware, methods or processes, or computer software on a computer-accessible medium.

Another general aspect includes a method of locking a linear actuator, the method comprising: urging axial movement of a piston away from a first piston position and toward a second piston position within an axial cavity defined by an inner surface of a housing, wherein the piston has a first piston end and a second piston end axially opposite the first piston end; pushing an axial movement of a lock finger by the piston, the lock finger attached to a first piston end at a first finger end and extending away from the piston to a second finger end in an extended configuration; contacting a face defined by the inner surface between a first housing portion in which the axial cavity has a first transverse dimension to a second housing portion in which the axial cavity has a second transverse dimension greater than the first transverse dimension with the second finger end; preventing movement of the piston to the second piston position by the contact; movement of an axially urging sleeve within said axial cavity from a first sleeve position to a second sleeve position; contacting the lock finger through the sleeve; urging the lock finger through the sleeve from the extended configuration to a retracted configuration in which the lock finger fits within the first housing portion; and moving the piston to the second piston position. Other embodiments of this aspect include corresponding computer systems, apparatus, and computer programs recorded on one or more computer storage devices, each configured to implement the actions of the methods.

Implementations may include one or more of the following features. The method, wherein urging axial movement of the piston away from the first piston position toward the second piston position within the axial cavity defined by the inner surface of the housing may further comprise applying fluid pressure to a pressure chamber defined at least in part by the inner surface, the piston, and a piston seal arranged in sealing contact with the piston and the inner surface. The method wherein axially urging movement of the sleeve within the axial cavity from the second sleeve position to the first sleeve position may further comprise urging movement of the sleeve by a spring bias. The method may further comprise: axially urging movement of the sleeve within the axial cavity from the second sleeve position to the first sleeve position; urging the piston away from the second piston position to the first piston position; passing the second finger end out of the first housing portion, past the face, and into the second housing portion; and extending the lock finger away from the piston from the retracted configuration to the extended configuration. The method, wherein extending the lock finger away from the piston from the retracted configuration to the extended configuration may include extending the lock finger away from the piston from the retracted configuration to the extended configuration with a biasing member. The method wherein axially urging the sleeve to move within the axial cavity from the second sleeve position to the first sleeve position may comprise applying fluid pressure to a pressure chamber defined by the inner surface, an outer surface of the sleeve, a first seal arranged in sealing contact with the inner surface and the outer surface of the sleeve, and a second seal arranged in sealing contact with the inner surface and the outer surface of the sleeve. The method wherein axially urging movement of the sleeve within the axial cavity from the second sleeve position to the first sleeve position may comprise urging movement of the sleeve by a biasing member configured to axially urge movement of the sleeve from the second sleeve position to the first sleeve position. The method, wherein preventing movement of the piston to the second piston position by the contact may comprise: contacting a second face defined by the piston with the second finger end; and transmitting the axial force of the piston to the housing through the second finger end. Implementations of the described technology may include hardware, methods or processes, or computer software on a computer-accessible medium.

Another general aspect includes a thrust reverser actuator system comprising a fuselage structure, a thrust reverser cowl configured to move relative to the fuselage structure, a linear actuator configured to move the thrust reverser cowl relative to the fuselage structure, and a lock device, and comprising: a housing having an inner surface defining an axial cavity, the housing comprising a first housing portion wherein the axial cavity has a first transverse dimension, a second housing portion wherein the axial cavity has a second transverse dimension greater than the first transverse dimension, and a face defined by the inner surface from the first housing portion to the second housing portion; a piston having a first piston end and a second piston end axially opposite the first piston end, wherein the piston is configured for axial movement within the axial cavity between a first piston position and a second piston position. The lock device includes: a lock finger attached to the first piston end at a first finger end and extending away from the piston to a second finger end, wherein the second finger end is configured to contact the face in an extended configuration and fit within the first housing portion in a retracted configuration; and a sleeve disposed within the second housing portion and configured to move axially within the second housing portion between a first sleeve position in which the lock finger is permitted to extend to the extended configuration and a second sleeve position configured to contact the lock finger and urge the lock finger to the retracted configuration. Other embodiments of this aspect include corresponding computer systems, apparatus, and computer programs recorded on one or more computer storage devices, each configured to implement the actions of the methods.

Implementations may include one or more of the following features. The system, wherein the lock finger may be configured to prevent movement of the piston toward the second piston position in the extended configuration and to permit movement of the piston toward the second piston position in the retracted configuration. The system may include a pressure chamber defined at least in part by the inner surface, the piston, and a piston seal arranged in sealing contact with the piston and the inner surface, wherein the piston may be configured to be urged from the first piston position toward the second piston position by fluid pressure provided within the pressure chamber. The system may also include hardware, methods or processes, or computer software on a computer-accessible medium.

The systems and techniques described here may provide one or more of the following advantages. First, the system may provide a lock mechanism with a short lock loading path. Second, the system is less prone to fatigue from flexing. Third, the lock fingers are not limited by the size of the deflection requirements. Fourth, the lock load does not use the lock fingers as the primary load path.

The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features and advantages will be apparent from the description and drawings, and from the claims.

Drawings

FIG. 1 is a schematic view of an exemplary turbofan jet engine with a portion of the outer nacelle cut away for clarity.

FIG. 2 is a schematic illustration of the engine of FIG. 1 with an exemplary thrust reverser.

FIG. 3 is a schematic illustration of the engine of FIG. 1 with an alternative exemplary thrust reverser.

FIG. 4 is a perspective view of an exemplary linear hydraulic actuator.

Fig. 5-9 are cross-sectional views of an exemplary linear lock assembly.

Fig. 10 and 11 are cross-sectional views of another exemplary linear lock assembly.

FIG. 12 is a flow chart of an example process of locking a linear actuator.

Detailed Description

This document describes systems and techniques for reversing aircraft turbine engine airflow. A thrust reverser with at least one movable element movable to and from a reversing position may be used to change the direction of the bypass airflow. In the reverse position, the movable element may be configured to reverse at least a portion of the bypass airflow.

The locking mechanism engages the thrust reverser to prevent inadvertent activation or inadvertent deployment (e.g., during flight, during ground maintenance operations). The following paragraphs describe a mechanism that provides such locking in an assembly that is relatively light and less complex than prior designs.

FIG. 1 illustrates an example turbofan jet engine assembly 10 having a turbine engine 12, a fan assembly 13, and a nacelle 14 (e.g., airframe structure). Portions of the nacelle 14 have been cut away for clarity. A nacelle 14 surrounds the turbine engine 12 and defines an annular airflow path or annular bypass duct 16 through the jet engine assembly 10 to define a generally forward-to-aft bypass airflow path as schematically shown by arrow 18. The flow of combustion gases is schematically indicated by arrows 19.

A thrust reverser with at least one movable element movable to and from a reversing position may be used to change the direction of the bypass airflow. In the reverse position, the movable element may be configured to reverse at least a portion of the bypass airflow. There are a number of ways to achieve reverse thrust on turbofan jet engine assemblies. Fig. 2 schematically illustrates one example of a thrust reverser 20 that may be used in the turbofan jet engine assembly 10. The thrust reverser 20 includes a movable element 22. The movable element 22 has been shown as a shroud portion that is axially movable relative to a forward portion of the nacelle 14. Hydraulic actuator 24 may be coupled to movable member 22 to move movable member 22 into and out of the reverse position. In the reverse position, as illustrated, the movable element 22 limits an annular bypass area between the movable element 22 and the turbine engine 12, which also opens a portion 26 between the movable element 22 and a forward portion of the nacelle 14 so that the airflow path may be reversed as illustrated by arrow 28. An optional deflector or flap (also referred to as a blocker door) 29 may be included to help direct the airflow path between the movable element 22 and the forward portion of the nacelle 14.

Fig. 3 schematically shows an alternative example of a thrust reverser 30. The thrust reverser 30 includes a movable element 32. The movable element 32 has been shown as a deflector, which may be built into a part of the nacelle 14. A hydraulic actuator 34 may be coupled to the movable member 32 to move the movable member 32 into and out of the reverse position. In the reverse position, shown in phantom and indicated at 36, the movable element 32 rotates the air outwardly and forwardly to reverse its direction, as shown by arrow 38. An optional deflector, blocker door or flap 39 may be included to help direct the airflow path outwardly.

In both illustrative examples, the thrust reverser changes the direction of thrust. Both thrust reverser 20 and thrust reverser 30 have been described as hydraulically operated systems, and the hydraulic actuators have been schematically shown. In some embodiments, thrust reverser 20 and/or thrust reverser 30 may be powered by other fluids (e.g., pneumatic), by electromechanical actuators, or by any other suitable power source or actuator type.

Fig. 4 is a perspective view of an exemplary linear hydraulic actuator 400. In some examples, hydraulic actuator 400 may be hydraulic actuator 24 of fig. 2 or hydraulic actuator 34 of fig. 3.

Hydraulic actuator 400 includes a housing 410 having an axial length represented by arrow 412. Hydraulic actuator 400 is configured as a linear actuator in which piston rod 414 may be axially extended and retracted relative to housing 410.

The hydraulic actuator 400 includes a mounting portion 420, the mounting portion 420 configured for attachment to an aircraft or fuselage structure, such as the example nacelle 14. Hydraulic actuator 400 also includes a mounting portion 422, mounting portion 422 being configured for attachment to an aircraft structure, such as the example movable element 22. In use, axial movement of the piston rod 414 causes movement of the movable element 22 relative to the nacelle 14.

As will be discussed in the description of fig. 5-9, the housing 410 defines one or more tubular cavities that form part of a pressure chamber that can be pressurized to perform the shifting and locking operations of the hydraulic actuator. The hydraulic actuator 400 also includes a linear lock assembly 500 configured to selectively prevent and allow axial movement of the piston rod 414. The remainder of this specification discusses linear lock assembly 500 in more detail.

Fig. 5-9 are cross-sectional side views of an exemplary linear lock assembly 500 apparatus in various operating configurations. Fig. 5 shows the linear lock assembly in a locked configuration. The views of fig. 5-9 show a portion of the housing 410 and a portion of the piston rod 414.

The housing 414 has an inner surface 502 that defines an axial cavity 504. Housing 410 includes a housing portion 506 and a housing portion 508. Along the interior of the housing portion 506, the axial cavity 504 has a first transverse dimension (e.g., diameter, cross-sectional area). Along the interior of the housing portion 508, the axial cavity 504 has a second transverse dimension (e.g., has a relatively larger diameter or cross-sectional area) that is greater than the first transverse dimension. At the junction where housing portion 506 meets housing portion 508, a face 510 is defined by the radial transition of inner surface 502 from the relatively smaller internal cavity dimension of housing portion 506 to the relatively larger internal cavity dimension of housing portion 508.

The piston rod 414 has a piston end 520 and a piston end 522 axially opposite the piston end 520. The piston rod 414 is configured for axial movement within the axial cavity 504 along an axial direction represented by arrow 524 between a first piston position (e.g., as shown in fig. 5, 6, and 9) and a second piston position (e.g., as shown in fig. 7-8). The piston seal assembly 526 provides a fluid seal between the piston rod 414 and the inner surface 502 of the housing portion 506. The piston seal assembly 526, piston rod 414, and inner surface 502 define a portion of a pressure chamber 530 on one side of the seal assembly 526 and a portion of a pressure chamber 532 on an axially opposite side of the seal assembly 526. In operation, piston rod 414 may be extended by applying pressurized fluid (e.g., hydraulic fluid) to pressure chamber 530 and may be retracted by applying pressurized fluid to pressure chamber 532.

Each of a set of lock fingers 540 is attached to the piston end 520 at a finger end 542 and extends away from the piston rod 414 to a finger end 544. Finger ends 544 are configured to contact face 510 when lock finger 540 is in the extended configuration (e.g., as shown in fig. 5 and 9) and to fit within housing portion 506 when lock finger 540 is in the retracted configuration (e.g., as shown in fig. 6-8).

The lock finger 540 is configured to be biased toward the locked configuration. In some embodiments, the finger end 542 may be fixed to the piston end 520, and the lock finger 540 may be formed of a compliant (e.g., spring) material that may bend and allow the finger end 544 to move between the extended and retracted positions. In some embodiments, the lock finger 540 may be substantially rigid, and the finger end 542 may be configured to pivot or articulate at the piston end 520, and the spring or other compliant material may be configured to bias the finger end 544 toward the extended position.

A sleeve 550 is disposed within the second housing portion and is configured to move axially within the housing portion 508 between a first sleeve position (e.g., as shown in fig. 5, 8, and 9) in which the lock fingers 540 are permitted to extend to the extended configuration and a second sleeve position configured to contact the lock fingers 540 and urge the lock fingers 540 to the retracted configuration (e.g., as shown in fig. 6 and 7).

Sleeve 550 includes a seal assembly 552 and a seal assembly 554. The inner surface 502, the outer surface 551 of the sleeve 550, the seal assembly 552, and the seal assembly 554 define a pressure chamber 556. A compliant member 558 (e.g., a spring) is configured to bias the sleeve 550 toward the second sleeve position. In use, the sleeve 550 is moved from the second sleeve position to the first sleeve position by applying fluid pressure to the pressure chamber 556 through the port 559.

With reference to fig. 5-9, an example operating cycle of the linear lock assembly 500 will be described. In fig. 5, the piston rod 414 is shown in the retracted configuration and the linear lock assembly 500 is shown in the locked configuration. In the locked configuration, the piston rod 414 is prevented from extending by the finger end 544. If an attempt is made to extend the piston rod 414 with the lock fingers 540 in the extended locked configuration, the finger ends 544 make interfering contact with the face 510. The extendable movement of the piston rod 414 is prevented in at least one of two different ways.

In one example, an axially forward side of one or more of the finger ends 544 may contact the face 510, and an axially face portion 546 of the plunger may contact an axially rearward side of the finger ends 544. Thus, the force acting on the piston rod 414 is transferred through the axial face portion 546 to the finger end 544 to the face 510 of the housing 410. Such mechanical interference substantially prevents further extension of the piston rod 414.

In another example, the force acting on the piston rod 414 may be transferred through the finger end 542, along the lock finger 540, to the finger end 544, and then to the face 510 of the housing 410. Such mechanical interference substantially prevents further extension of the piston rod 414.

Referring now to fig. 6, the piston rod 414 is shown in the retracted configuration and the linear lock assembly 500 is shown in the unlocked configuration. In the unlocked configuration, the lock fingers 540 are retracted (as represented by arrow 602) such that the finger ends 544 fit within the axial cavity 504 of the housing portion 506.

The lock finger 540 is moved from the locked configuration (e.g., shown in fig. 5) to the unlocked configuration (e.g., shown in fig. 6) by the sleeve 550. Fluid pressure blocked in the pressure chamber 556 is allowed to flow out of the port 559. With the fluid barrier removed, the compliant member 558 urges axial movement (represented by arrow 604) of the sleeve 550 from a locked position (e.g., as shown in fig. 5) to an unlocked position (e.g., as shown in fig. 6). As the sleeve 550 moves, the sleeve 550 contacts the lock fingers 540 and pushes retraction of the lock fingers 540 from the extended locked configuration to the retracted unlocked configuration.

Referring now to fig. 7, the piston rod 414 is shown in an extended configuration, with the linear lock assembly 500 shown in an unlocked configuration. In operation, the piston rod 414 may be urged from the retracted position toward the extended position by applying fluid pressure to the pressure chamber 530. With the lock fingers in the retracted, unlocked configuration, the finger ends 544 fit within the axial cavity 504 of the housing portion 506 and do not mechanically contact the face 510 when the piston rod 414 is moved (as represented by arrow 702) from the retracted position (e.g., as shown in fig. 5 and 6) toward the extended position (e.g., as shown in fig. 7).

Referring now to fig. 8, the piston rod 414 is shown in an extended configuration, wherein the linear lock assembly 500 is shown in an unlocked configuration and the sleeve 550 is in a locked position. When the piston rod 414 is in the extended configuration, the finger ends 544 fit within the axial cavity 504 of the housing portion 506. The axial cavity 504 prevents the finger ends 544 from extending due to the bias of the lock fingers 540 and thus keeps the lock fingers 540 retracted regardless of the position of the sleeve 550.

In the present example, with the lock fingers 540 held in the unlocked position by the axial cavity 504, the sleeve 550 may be moved without affecting the configuration of the lock fingers 540. The sleeve 550 may be moved away (as represented by arrow 802) from an unlocked configuration (e.g., as shown in fig. 6 and 7) toward a locked configuration (e.g., as shown in fig. 5, 8, and 9).

Upon application of pressurized fluid to the pressure chamber 556 through the port 559, the sleeve 550 moves toward the locked configuration, as represented by arrow 804. When the pressure in pressure chamber 556 is sufficient to overcome the bias of compliant member 558, sleeve 550 will move to the unlocked position.

Referring now to fig. 9, the piston rod 414 is shown in a retracted configuration, wherein the linear lock assembly 500 is shown in a locked configuration and the sleeve 550 is in a locked position. In operation, the piston rod 414 may be urged from the extended position toward the retracted position by applying fluid pressure to the pressure chamber 532. With the lock fingers in the retracted, unlocked configuration, the finger ends 544 fit within the axial cavity 504 of the housing portion 506 and will remain in the unlocked configuration. As the piston rod 414 moves (as represented by arrow 902) from the extended position (e.g., as shown in fig. 7 and 8) toward the extended position (e.g., as shown in fig. 5, 6, and 9), the finger ends 544 eventually pass out of the housing portion 506 into the housing portion 508. Once the finger ends 544 have exited the housing portion 506, the axial cavity 504 will no longer hold the lock fingers 540 in the unlocked position against the bias of the lock fingers 540. Thus, the bias of the lock fingers 540 causes the lock fingers 540 to extend (as represented by arrow 904) to a locked configuration.

Fig. 10 and 11 are cross-sectional views of another exemplary linear lock assembly 1000. The linear lock assembly 1000 is a modification of the exemplary linear lock assembly 500 of fig. 5-9, including an override assembly 1010. Generally, the override assembly 1010 is a mechanism that provides a way to manually disengage (e.g., unlock) the linear lock assembly 1000.

The override assembly 1010 includes a cam assembly 1020 and a sensor 1030. The cam assembly includes a shaft 1022 that extends through the housing 410 from a head 1024 to a cam 1026. The head 1024 is configured to be grasped or engaged by a tool or an operator's hand and rotated. For example, the head 1024 may be knurled to form a manual knob. In another example, the head 1024 may include a hex socket that may be engaged by a hex wrench. In another example, the head 1024 may include an octagonal structure (e.g., a bolt head) that may be engaged by a socket wrench. The cam 1026 is arranged to contact an axial face 1028 of the sleeve 550.

In use, the head 1024 can be rotated (as represented by arrow 1052) to cause the cam 1026 to rotate from a disengaged configuration (e.g., non-manual or mechanical override) as shown in fig. 10 to an engaged configuration (e.g., manual or mechanical override) as shown in fig. 11. The cam 1026 is asymmetric, and as the shaft 1022 rotates, the cam 1026 axially extends while contacting the axial face 1028. Rotation and extension of the cam 1026 urges axial movement (as represented by arrow 1054) of the sleeve 550 away from the locked configuration (e.g., as shown in fig. 10) toward the locked configuration (e.g., as shown in fig. 11). As described in the previous paragraph, movement of the sleeve 550 causes the sleeve 550 to contact the lock fingers 540 and urge the lock fingers 540 to move (as represented by arrows 1056) from the extended and locked position (e.g., shown in fig. 10) toward the retracted and unlocked position (e.g., shown in fig. 11).

The sensor 1030 is configured to detect the position of the cam assembly 1020, and thus the position of the locking sleeve. A torsion spring 1025 is provided to urge the cam 1026 against the locking sleeve 550. Torsion spring 1025 is configured to provide a force less than sufficient to override locking spring 558. This arrangement ensures that the sensor 1030 indicates the state of the lock (locked or unlocked) under all operating conditions, including fluid operation and manual override.

Fig. 12 is a flow diagram of an example process 1200 of locking a linear actuator. In some embodiments, the process 1200 may be used with the example linear lock assembly 400 of fig. 4-9 or the example linear lock assembly 1000 of fig. 10 and 11.

At 1210, axial movement of the piston is facilitated within an axial cavity defined by an inner surface of the housing. The piston has a first piston end and a second piston end axially opposite the first piston end. The piston is urged away from the first piston position and toward the second piston position. For example, as shown in fig. 7, the piston rod 414 is pushed in the direction of arrow 702.

In some embodiments, urging axial movement of the piston away from a first piston position toward a second piston position within the axial cavity defined by the inner surface of the housing further may include applying fluid pressure to a pressure chamber defined at least in part by the inner surface, the piston, and a piston seal arranged in sealing contact with the piston and the inner surface. For example, pressurized fluid may be applied to the pressure chamber 530 to urge extension of the piston rod 414 relative to the housing 410 (e.g., in the direction of arrow 702 of fig. 7).

At 1220, the axial movement of the lock fingers is pushed by the piston. The lock finger is attached to the first piston end at a first finger end and extends away from the piston to a second finger end in the extended configuration. For example, the lock finger 540 is attached to the piston end 520 at the finger end 542 and extends away from the piston rod 414 to the finger end 544. When the piston rod 414 moves axially, the lock finger 540 moves with the piston rod 414.

At 1230, the second finger end contacts a face defined by the inner surface between a first housing portion in which the axial cavity has a first transverse dimension to a second housing portion in which the axial cavity has a second transverse dimension that is greater than the first transverse dimension. For example, inner surface 502 defines an axial face 510 at the transition between housing portion 506 and housing portion 508. As the piston rod 414 and lock finger 540 move, the finger end 544 contacts the face 510.

At 1240, the contact prevents movement of the piston to the second piston position. For example, referring to fig. 5, the piston rod 414 will not extend due to contact between the finger ends 544 and the face 510. This contact provides mechanical interference that prevents extension of the piston rod 414 relative to the housing 410.

In some embodiments, preventing movement of the piston to the second piston position by the contact may further comprise: contacting a second face defined by the piston with the second finger end; and transmitting the axial force of the piston to the housing through the second finger end. For example, the moving force of the piston rod 414 may be transferred from the axial face portion 546 to the face 510 through the finger end 544.

At 1250, axial movement of the push sleeve within the axial cavity from the first sleeve position to the second sleeve position is facilitated. For example, the sleeve 550 moves in the direction indicated by arrow 604 from the example position shown in fig. 5 to the example position shown in fig. 6.

In some embodiments, the movement of the axial push sleeve from the first sleeve position to the second sleeve position within the axial cavity may include applying fluid pressure to the pressure chamber. For example, the sleeve 550 may be moved from the example position shown in fig. 5 to the example position shown in fig. 6 in the direction indicated by arrow 604 by fluid pressure applied to the pressure chamber 530. In some embodiments, the sleeve may be axially movable by a bias provided by a spring or other such compliant member (such as compliant member 558).

At 1260, the sleeve contacts the lock fingers. For example, as shown in fig. 6, the sleeve 550 is in contact with the lock fingers 540.

At 1270, the sleeve pushes the lock fingers from the extended configuration to a retracted configuration in which the lock fingers fit within the first housing portion. For example, as shown in fig. 6-8, the lock finger 540 has been retracted to fit within the cavity 504.

At 1280, the piston is moved to a second piston position. For example, as shown in fig. 7, with the lock fingers 540 in the retracted position, the piston rod 414 may extend in the direction of arrow 702.

In some implementations, the process 1200 may include: axially urging movement of the sleeve within the axial cavity from the second sleeve position to the first sleeve position; urging the piston away from the second piston position to the first piston position; passing the second finger end out of the first housing portion, past the face, and into the second housing portion; and extending the lock finger away from the piston from the retracted configuration to the extended configuration. For example, the piston rod 414 may be retracted from the example position shown in fig. 8 toward the example position shown in fig. 9 (e.g., in the direction of arrow 902). When the finger end 544 exits the housing portion 506, it may extend (e.g., snap) into the extended locking configuration shown in fig. 9.

In some embodiments, extending the lock finger away from the piston from the retracted configuration to the extended configuration may include extending the lock finger away from the piston from the retracted configuration to the extended configuration with a biasing member. For example, the lock finger 540 may include an extended spring (not shown) configured to urge the finger end 544 away from the piston rod 414. In another example, the lock fingers themselves may be made of a spring material and may be configured to urge the finger ends 544 away from the extension of the piston rod 414.

In some embodiments, axially urging the sleeve to move within the axial cavity from the second sleeve position to the first sleeve position may include applying fluid pressure to a pressure chamber defined by the inner surface, an outer surface of the sleeve, a first seal arranged in sealing contact with the inner surface and the outer surface of the sleeve, and a second seal arranged in sealing contact with the inner surface and the outer surface of the sleeve. For example, pressurized fluid may be applied to the pressure chamber 556 to move the sleeve 550 in the direction of arrow 802 of fig. 8.

In some embodiments, axially urging movement of the sleeve from the second sleeve position to the first sleeve position within the axial cavity may include urging movement of the sleeve by a biasing member configured to axially urge movement of the sleeve from the second sleeve position to the first sleeve position. For example, the compliant member 558 may be configured to bias the sleeve 550 toward the locked position.

Although several embodiments have been described in detail above, other modifications are possible. For example, the logic flows depicted in the figures do not require the particular order shown, or sequential order, to achieve desirable results. In addition, other steps may be provided, or steps may be eliminated, from the described flows, and other components may be added to, or removed from, the described systems. Accordingly, other implementations are within the scope of the following claims.