1. A thrust reverser control system, comprising:
a power drive unit operable to supply a drive force;
at least two drive mechanisms each coupled to receive the drive force from the power drive unit; and
at least two actuator assemblies, each actuator assembly coupled to at least one of the drive mechanisms and including:
an actuator coupled to receive the drive force from one of the drive mechanisms, the actuator having at least one end that rotates in response to the drive force and configured to move, upon receipt of the drive force, between a stowed position and a deployed position, the actuator
a torque limiter assembly mounted to the end of the actuator and configured to limit torque in the actuator assembly upon a torque magnitude being reached in at least the actuator while allowing continued rotation of the at least one end of the actuator.
2. The system of claim 1, wherein the actuator comprises:
a rotationally mounted actuator shaft configured to rotate, upon receipt of the drive force, in a stow direction and a deploy direction; and
an extension tube mounted on the actuator shaft and coupled to the torque limiter assembly, the extension tube configured to translate between the stowed position and the deployed position in response to actuator shaft rotation in the stow direction and the deploy direction, respectively.
3. The system of claim 2, further comprising:
a rod end assembly selectively moveably coupled to the torque limiter assembly, the rod end assembly configured to selectively rotate relative to the extension tube, and adapted to couple to a thrust reverser moveable component.
4. The system of claim 3, wherein the torque limiter assembly at least partially decouples the extension tube in the rod end assembly upon the torque magnitude being reached in the extension tube, to thereby limit torque applied to the actuator assembly.
5. The system of claim 2, wherein the extension tube is further configured to rotate in substantial synchronism with the actuator shaft when the torque limiter assembly limits the applied torque.
6. (canceled).
7. The system of claim 2, wherein:
the actuator shaft comprises a ball screw; and
the extension tube comprises a ball nut mounted on the ball screw, the ball nut configured to translate between the stowed position and the deployed position in response to ball screw rotation in the stow direction and the deploy direction, respectively.
8. The system of claim 3, wherein the torque limiter assembly comprises:
at least two roller pins, each roller pin having an outer surface and moveably mounted in a groove formed in the rod end assembly; and
at least two substantially resilient cantilever arms each having a fixed end and a free end, each cantilever arm fixed end fixedly coupled to the actuator and each cantilever arm free end in contact with the outer surface of one of the roller pins, to thereby apply a radial load thereon.
9. The system of claim 8, wherein:
the grooves formed in the rod end assembly each have a substantially equivalent groove depth; and
the torque magnitude at which the torque limiter assembly limits torque applied to the actuator assembly is based, at least in pan, on groove depth.
10. The system of claim 8, wherein the torque magnitude at which the torque limiter assembly limits torque applied to the actuator assembly is based, at least in part, on the radial load applied by each cantilever arm on each roller pin.
11. The system of claim 8, wherein each of the roller pins rolls out of one groove and into an adjacent groove when the torque magnitude is reached, to thereby at least partially decouple the actuator from the rod end assembly.
12. The actuator assembly of claim 3, further comprising:
a thrust bearing assembly coupled between the actuator and the torque limiter assembly.
13. The actuator of claim 12, wherein the thrust bearing assembly comprises:
a bearing groove formed in at least one of the actuator and the rod end assembly; and
a plurality of ball bearings disposed within the bearing groove and in moveable contact with the actuator and the rod end assembly,
wherein the bearing groove and ball bearings are configured to transmit an axial force between the actuator and the rod end assembly and, when the torque magnitude is reached, whereby relative rotation between the actuator and the rod end assembly is allowed.
14. A thrust reverser actuator assembly, comprising:
an actuator adapted to receive a drive force, the actuator having at least one end that rotates in response to the drive force and configured, in response to receipt of the drive force, to move between a stowed position and a deployed position; and
a torque limiter assembly mounted to the end of the actuator and configured to limit torque applied to the actuator assembly upon a torque magnitude being reached in at least the actuator while allowing continued rotation of the at least one end of the actuator.
15. The actuator assembly of claim 14, wherein the actuator comprises:
a rotationally mounted actuator shaft configured to rotate, upon receipt of the drive force, in a stow direction and a deploy direction; and
an extension tube mounted on the actuator shaft and coupled to the torque limiter assembly, the extension tube configured to translate between the stowed position and the deployed position in response to actuator shaft rotation in the stow direction and the deploy direction, respectively.
16. The actuator assembly of claim 15, further comprising:
a rod end assembly coupled to the torque limiter assembly, the rod end assembly configured to selectively rotate relative to the extension tube and the torque limiter assembly, and adapted to couple to a thrust reverser moveable component.
17. The actuator assembly of claim 16, wherein the torque limiter assembly at least partially decouples the extension tube from the rod end assembly upon the torque magnitude being reached in the extension tube, to thereby limit torque applied to the actuator assembly.
18. The actuator assembly of claim 15, wherein the extension tube is further configured to rotate in substantial synchronism with the actuator shaft when the torque limiter assembly limits the applied torque.
19. The actuator assembly of claim 15, wherein:
the actuator shaft comprises a ball screw; and
the extension tube comprises a ball nut mounted on the ball screw, the ball nut configured to translate between the stowed position and the deployed position in response to ball screw rotation in the stow direction and the deploy direction, respectively.
20. The actuator assembly of claim 16, wherein the torque limiter assembly comprises:
at least two roller pins, each roller pin having an outer surface and moveably mounted in a groove formed in the rod end assembly; and
at least two substantially resilient cantilever arms each having a fixed end and a free end, each cantilever arm fixed end fixedly coupled to the actuator and each cantilever arm free end in contact with the outer surface of one of the roller pins, to thereby apply a radial load thereon.
21. The actuator assembly of claim 20, wherein:
the grooves formed in the rod end assembly each have a substantially equivalent groove depth; and
the torque magnitude at which the torque limiter assembly limits torque applied to the actuator assembly is based, at least in part, on groove depth.
22. The actuator assembly of claim 20, wherein the torque magnitude at which the torque limiter assembly limits torque applied to the actuator assembly is based, at least in part, on the radial load applied by each cantilever arm on each roller pin.
23. The actuator assembly of claim 20, wherein each of the roller pins rolls out of one groove and into an adjacent groove when the torque magnitude is reached, to thereby at least partially decouple the actuator from the rod end assembly.
24. The actuator assembly of claim 16, further comprising:
a thrust bearing assembly coupled between the actuator and the torque limiter assembly assembly.
25. The actuator assembly of claim 15, wherein the thrust bearing assembly comprises:
a bearing groove formed in at least one of the actuator and the rod end assembly; and
a plurality of ball bearings disposed within the bearing groove and in moveable contact with the actuator and the rod end assembly,
wherein the bearing groove and ball bearings are configured to transmit an axial force between the actuator and the rod end assembly and, when the torque magnitude is reached, whereby relative rotation between the actuator and the rod end assembly is allowed.
26. A torque limiter assembly configured to limit torque transmission between an aircraft thrust reverser actuator and a rod end assembly, the torque limiter assembly comprising:
at least two roller pins, each roller pin having an outer surface and moveably mounted in a groove formed in the rod end assembly; and
at least two substantially resilient cantilever arms each having a fixed end and a fee end, each cantilever arm fixed end configured to fixedly couple to the actuator and each cantilever arm free end in contact with the outer surface of one of the roller pins, to thereby apply a predetermined radial load thereon.
27. The torque limiter assembly of claim 26,
the grooves formed in the rod end assembly each have a substantially equivalent groove depth; and
the torque magnitude at which the torque limiter assembly limits torque transmission is based, at least in part, on groove depth.
28. The torque limiter assembly of claim 26, wherein the torque magnitude at which the torque limiter assembly limits torque transmission is based, at least in part, on the radial load applied by each cantilever arm on each roller pin
29. limiter assembly of claim 26, wherein each of the roller pins is configured to roll out of one groove and into an adjacent groove when the torque magnitude is reached, to thereby at least partially decouple the actuator from the rod end assembly.
30. A rod end assembly for coupling to a thrust reverser moveable component, comprising:
a main body having an outer peripheral surface;
two or more pin grooves formed in, and evenly spaced around, the main body outer peripheral surface; and
a bearing groove formed in, and circumscribing, the main body outer peripheral surface, the bearing groove adapted to receive a plurality of ball bearings therein.
31. In a thrust reverser actuator assembly having at least an actuator adapted to translate, a method of limiting torque in the actuator assembly, comprising:
sensing a torque magnitude applied to at least the actuator; and
limiting torque applied to the actuator assembly when at least a predetermined torque magnitude is reached in the actuator.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A lithographic projection apparatus, comprising:
a movable table;
a projection system configured to project a patterned beam onto a target portion of a substrate, the projection system comprising a final optical element having a bottom surface; and
a liquid supply system configured to at least partly fill a space between the projection system and the table with a liquid to form a liquid reservoir between the bottom surface and the table, the liquid supply system comprising an inlet to provide liquid to the space, and an overflow opening to accept liquid from the liquid reservoir only when the liquid exceeds a certain level above the bottom surface and to remove the liquid that exceeds the level.
2. The apparatus of claim 1, wherein the overflow opening is arranged above the inlet.
3. The apparatus of claim 1, further comprising a barrier configured to bound the liquid, the overflow opening positioned at a side of the barrier opposite to a side of the barrier that faces the table.
4. The apparatus of claim 3, wherein the overflow opening is arranged such that the liquid only flows into the overflow opening when the liquid flows over the top of the barrier.
5. The apparatus of claim 3, wherein the barrier comprises, in the side of the barrier that faces the table, an outlet to remove liquid from the space.
6. The apparatus of claim 1, further comprising a gas tight member configured to seal a space above the liquid.
7. The apparatus of claim 1, further comprising:
a liquid confinement structure extending along at least a part of the boundary of the space between the projection system and the table; and
a passage between at least part of the liquid confinement structure and the projection system, the overflow opening arranged to remove liquid at the end of at least part of the passage.
8. The apparatus of claim 1, further comprising a liquid confinement structure extending along at least a part of the boundary of the space between the projection system and the table and defining an aperture through which the patterned beam is projected, the aperture being between the projection system and the table; and
wherein the inlet to provide liquid to the space has an opening above the aperture, the inlet opening adjacent to an inner periphery of the liquid confinement structure.
9. The apparatus of claim 1, wherein the liquid reservoir covers a smaller area than the substrate.
10. The apparatus of claim 1, further comprising a liquid confinement structure extending along at least a part of the boundary of the space between the projection system and the table, the liquid confinement structure having the inlet to supply liquid to the space and the inlet is arranged to supply liquid to contact a surface, facing toward the table, of an optical element of the projection system, the inlet extending diagonally toward the table and having an opening between the surface of the optical element and the table.
11. The apparatus of claim 1, further comprising:
a liquid confinement structure extending along at least a part of the boundary of the space between the projection system and the table, the liquid confinement structure having a bottom surface facing the table and an upper surface above a surface, facing toward the table, of an optical element of the projection system, the overflow opening being at the upper surface; and
a passage between the optical element and at least part of the liquid confinement structure to allow movement of liquid to the overflow opening,
wherein the inlet to provide liquid has an opening that is located above the bottom surface, liquid from the inlet opening flowing to contact the surface of the optical element, flowing to below the bottom surface and flowing toward the overflow opening.
12. A lithographic projection apparatus comprising:
a movable table;
a projection system configured to project a patterned beam onto a target portion of a substrate, the projection system comprising a final optical element having a bottom surface; and
a liquid supply system configured to at least partly fill a space between the projection system and the table with a liquid to form a liquid reservoir, the liquid supply system comprising:
an inlet to provide liquid to the space, and
an overflow opening to accept liquid from the liquid reservoir only when the liquid exceeds a certain level above the bottom surface and to remove the liquid that exceeds the level, the inlet being below the certain level.
13. The apparatus of claim 12, further comprising a barrier configured to bound the liquid, the overflow opening positioned at a side of the barrier opposite to a side of the barrier that faces the table.
14. The apparatus of claim 12, further comprising:
a liquid confinement structure extending along at least a part of the boundary of the space between the projection system and the table and defining an aperture through which the patterned beam is projected, the aperture being between the projection system and the table; and
the inlet is configured to provide liquid to the space above the aperture, the inlet being adjacent to an inner periphery of the liquid confinement structure.
15. The apparatus of claim 12, further comprising:
a liquid confinement structure extending along at least a part of the boundary of the space between the projection system and the table, the liquid confinement structure having a bottom surface facing the table and an upper surface above the bottom surface of the final optical element, the overflow opening being at the upper surface; and
a passage between the final optical element and at least part of the liquid confinement structure to allow movement of liquid to the overflow opening,
wherein the liquid confinement structure comprises the inlet, the inlet having an opening that is located above the bottom surface of the liquid confinement structure, liquid from the inlet opening flowing to contact the bottom surface of the final optical element, flowing to below the bottom surface of the liquid confinement structure and flowing toward the overflow opening.
16. A lithographic projection apparatus, comprising:
a movable table;
a projection system configured to project a patterned beam onto a target portion of a substrate; and
a liquid handling system configured to at least partly fill a space between the projection system and the table with a liquid to form a liquid reservoir, the liquid handling system comprising:
an overflow opening to accept liquid from the liquid reservoir only when the liquid exceeds a certain level and to remove the liquid that exceeds the level,
a liquid confinement structure extending along at least a part of the boundary of the space between the projection system and the table and defining an aperture through which the patterned beam is projected, the aperture being between the projection system and the table, and
an inlet to provide liquid to the space above the aperture, the inlet adjacent to an inner periphery of the liquid confinement structure.
17. The apparatus of claim 16, wherein the overflow opening is positioned at a side of the liquid confinement structure opposite to a side of the liquid confinement structure that faces the table.
18. The apparatus of claim 16, wherein the inlet is below the certain level.
19. The apparatus of claim 16, further comprising a passage between an optical element of the projection system and at least part of the liquid confinement structure to allow movement of liquid to the overflow opening,
wherein the liquid confinement structure has a bottom surface facing the table and an upper surface above a surface, facing toward the table, of the optical element, the overflow opening being at the upper surface, and
wherein the inlet to provide liquid has an opening that is located above the bottom surface, liquid from the inlet opening flowing to contact the surface of the optical element, flowing to below the bottom surface and flowing toward the overflow opening.
20. A lithographic projection apparatus, comprising:
a movable table;
a projection system configured to project a patterned beam onto a target portion of a substrate; and
a liquid supply system configured to at least partly fill a space between the projection system and the table with a liquid to form a liquid reservoir, the liquid supply system comprising:
an overflow opening to accept liquid from the liquid reservoir only when the liquid exceeds a certain level and to remove the liquid that exceeds the level, and
an inlet to provide liquid to the space, wherein the overflow opening is arranged above the inlet.