Pivoting door thrust reverser for a turbofan gas turbine engine
View Patent ↗A pivot arrangement for a thrust reverser door of a gas turbine engine, the pivot fitting having a base and a shaft projecting from a main side of the base. The shaft receives a preferably curved pivot arm of the door to provide a low profile arrangement which improves performance when the doors are stowed.
1. A thrust reverser comprising:
first and second doors, each having a pair of opposed pivot arms;
a jet pipe having a pair of jet pipe arms and a radially inner mold line surface for bounding discharge of exhaust gas; and
a pair of pivot fittings inserted into corresponding recesses radially inside each jet pipe arm substantially flush with said inner mold line surface, each pivot fitting having a projection extending outwardly through an opening in the jet pipe arm, each projection received in a pivot hole in a corresponding pivot arm.
2. A thrust reverser according to claim 1 wherein each pivot fitting has a shaft projecting from a first side of a base, the shaft extending through said opening in said jet pipe arm, the base remaining on the inside of the jet pipe while the shaft projects through the opening to the outside of the jet pipe, the opening sized to allow the shaft to pass therethrough but prevent the base from passing therethrough, the shaft rotatably receiving said pivot arm of the door.
3. The thrust reverser as defined in claim 2 , wherein the shaft comprises a fastening assembly for securing an end of the pivot arm of the thrust reverser door.
4. The thrust reverser as defined in claim 2 , further comprising a plurality of threaded fasteners removably securing the base to the jet pipe.
5. The thrust reverser as defined in claim 2 , wherein the jet pipe has a recess co-operatively receiving the base.
6. The thrust reverser as defined in claim 2 , wherein the base is mounted to the jet pipe from an inside of the jet pipe.
7. The thrust reverser as defined in claim 2 , wherein the base has a second side which is substantially flush with said inner mold line surface of the jet pipe.
8. The thrust reverser as defined in claim 7 , wherein the base second side has a radius of curvature substantially the same as a radius of curvature of the jet pipe in the region where the base is mounted.
9. The thrust reverser as defined in claim 2 , further comprising a washer separating an inner side of the pivot arm from the first side of the base, the washer having a width selected to provide a desired spacing upon adjustment of the door.
10. The thrust reverser as defined in claim 1 , wherein each pivot fitting has a base mounted to the jet pipe from inside of the jet pipe.
11. The thrust reverser as defined in claim 10 , wherein each base has an inner side which is substantially flush with said inner mold line surface of the jet pipe.
12. The thrust reverser as defined in claim 11 , wherein the inner side of each base has a radius of curvature substantially the same as a radius of curvature of the jet pipe in the region where the base is mounted.
13. The thrust reverser as defined in claim 1 , wherein each pivot fitting includes fasteners extending therethrough for fastening the fitting to the jet pipe.
14. The thrust reverser as defined in claim 10 , further comprising a washer separating an inner side of the pivot arm from an outer side of the base, the washer having a width selected to provide a desired spacing upon adjustment of the door.
15. A method of pivotally connecting a thrust reverser door to a thrust reverser according to claim 1 , the method comprising the steps of:
providing said opening in one of said jet pipe arms;
providing said first door having said pivot hole;
inserting a first pivot fitting through the opening from an inside of the jet pipe so that said projection defines a pivot of the first pivot fitting extending to an outward side of the jet pipe and through the pivot hole of the first door; and
attaching the first pivot fitting to said one jet pipe arm.
16. The method as defined in claim 15 , further comprising repeating said steps to provide a second pivot connection for the second door.
17. The method as defined in claim 15 , further comprising the step of connecting a fastener to a free end of the first pivot to retain the first door to the first pivot.
18. The method as defined in claim 15 , further comprising performing said steps in substantially reverse order to disconnect the first door from the thrust reverser.
19. A thrust reverser according to claim 1 wherein:
said first and second doors form an exit nozzle having a radius of curvature; and
each door comprises a circumferentially-extending thrust deflecting portion and said pair of pivot arms are disposed on either side of the deflecting portion, the pivot arms configured to pivotally mount the door to said jet pipe, the arms extending from said thrust deflecting portion to a free end, the arms having corresponding radius of curvature following said exit nozzle curvature, with adjacent pivot arms curving around each other.
20. A thrust reverser having a first side and a second side, a pair of first side door pivots and a pair of second side door pivots, and a first side thrust-reverser door and a second side thrust-reverser door, the doors each having a pair of pivot arms extending therefrom, the first side door mounted on the first side of the thrust reverser through connection to the second side pivots, the second side door mounted on the second side of the thrust reverser through connection to the first side pivots, the first and second door pivot arms thus crossing one another when the doors are closed, wherein the pivot arms are inwardly curved and wherein at least one of the doors has pivot arms which are curved to avoid interference with the pivot arms of the other door.
21. The thrust reverser as defined in claim 20 , wherein said doors form an exit nozzle having a radius of curvature, and the pivot arm curvature substantially follows the exit nozzle radius of curvature.
22. The thrust reverser as defined in claim 20 , wherein the pivot arm curvature is configured to curve around a pivot arm of an adjacently-mounted door of the thrust reverser.
23. A thrust reverser comprising:
a pair of thrust reverser doors surrounding a jet pipe to form an exhaust nozzle having aerodynamic outer and inner mold line surfaces;
said jet pipe including a pair of side arms having radially inner surfaces defining corresponding portions of said inner mold line surface;
each door having a pair of pivot arms pivotally mounted at corresponding pivot fittings to said jet pipe arms; and
each of said pivot fittings includes a base disposed radially inside said jet pipe and substantially flush with said inner mold line surface, and a shaft extending outwardly through said jet pipe and pivotally connected to corresponding ones of said pivot arms.
24. A thrust reverser according to claim 23 wherein said pivot fitting bases are fixedly mounted to said jet pipe flush with said inner mold line surface.
25. A thrust reverser according to claim 24 wherein said pivot arms conform in curvature with said exhaust nozzle radially between said outer and inner mold line surfaces.
26. A thrust reverser according to claim 25 wherein each of said pivot fittings further comprises a bearing mounted on said shaft inside a corresponding aperture in said pivot arms, with outer and inner washers bounding said bearing on said shaft, and a bolt engages said shaft to secure in turn said outer washer, bearing, and inner washer on said shaft.
27. A thrust reverser according to claim 25 wherein adjacent pivot arms of said doors cross and overlap each other radially between said outer and inner mold line surfaces.