Shape memory wire actuated aircraft door seal

• US 6,009,669 A
• Filed: 03/11/1999
• Issued: 01/04/2000
• Est. Priority Date: 03/11/1999
• Status: Expired due to Fees

• Current Assignee: Northrop Grumman Corporation
• Original Assignee: Northrop Grumman Corporation
• Inventors: Gerhardt, Heinrich, Palusamy, Arun Robert, Gomez, Raymond David, Jardine, Andrew Peter
• Primary Examiner(s): Stodola, Daniel P.
• Assistant Examiner(s): Cohen, Curtis A.
• Application Number:
  US09/268,510
• Time in Patent Office: 299 Days
• Field of Search: 49/309, 49/303, 49/306, 49/310, 49/312, 49/316, 49/417, 49/318, 49/319, 49/490.1
• US Class Current: 49/316
• CPC Class Codes: B64C 1/14 Windows; Doors; Hatch covers or access panels; Surrounding frame structures; Canopies; Windscreens accessories therefor, e.g. pressure sensors, water deflectors, hinges, seals, handles, latches, windscreen wipersfairings movable in conjunction with undercarriage elements B64C25/16; bomb doors B64D1/06

Abstract

An aircraft door adapted to substantially seal with a door frame. The aircraft door is provided with an edge portion which is formed to engage the door frame. The edge portion has a sealed position wherein the edge portion is engaged with the door frame. The edge portion further has an unsealed position wherein the edge portion is spaced from the door frame. The aircraft door is further provided with a substantially rigid door body and an elastic portion interposed between the door body and the edge portion. The elastic portion is selectively expandable and compressible for permitting movement of the edge portion between the sealed and unsealed positions. The aircraft door is further provided with an actuator device which mechanically couples the door body with the edge portion for selectively moving the edge portion between the sealed and unsealed positions. The actuator device comprises a shape memory metal material having a predetermined transition temperature. The actuator device assumes a contracted state when above the transition temperature and the edge portion is sized and configured to be in the unsealed position. The actuator device assumes an expanded state when below the transition temperature and the edge portion is sized and configured to be in the sealed position.

Claims

1. An aircraft door adapted to substantially seal with a door frame, the aircraft door comprising:

an edge portion formed to be engagable with the door frame, the edge portion having a sealed position wherein the edge portion is engagable with the door frame, the edge portion having an unsealed position wherein the edge portion is not engagable with the door frame;

a substantially rigid door body;

an elastic portion interposed between the door body and the edge portion, the elastic portion being selectively expandable and compressible for permitting movement of the edge portion between the sealed and unsealed portions;

an actuator device mechanically coupling the door body with a the edge portion for selectively moving the edge portion between the sealed and unsealed positions, the actuator device comprising a shape memory metal material having a predetermined transition temperature;

wherein the actuator device assuming a contracted state when above the transition temperature and the edge portion being sized and configured to be in the unsealed position; and

wherein the actuator device assuming an expanded state when below the transition temperature and the edge porting being sized and configured to be in the sealed position.

2. The aircraft door of claim 1 wherein the actuator device comprises a shape memory metal wire.

3. The aircraft door of claim 2 wherein the actuator device further comprises a heat source in thermal communication with the shape memory metal wire for selectively heating the shape memory wire above and below the transition temperature.

4. The aircraft door of claim 3 wherein the heat source comprises a thermal strip.

5. The aircraft door of claim 3 wherein the shape memory metal wire having first and second ends in thermal communication with the heat source.

6. The aircraft door of claim 5 wherein the shape memory metal wire having a wire body interposed between the first and second ends, the wire body being looped about the edge portion.

7. The aircraft door of claim 2 wherein the shape memory wire having a diameter of about 0.01 inches.

8. The aircraft door of claim 2 wherein the shape memory wire being in slidable communication with the elastic portion.

9. The aircraft door of claim 2 wherein the shape memory wire being in slidable communication with the edge portion.

10. The aircraft door of claim 1 wherein the actuator device comprises a plurality of shape memory metal wires arrayed to collectively move the edge portion between the sealed and unsealed positions.

11. The aircraft door of claim 1 wherein the actuator device being pre-strained to compress the elastic material when the actuator device is at the transition temperature.

12. The aircraft door of claim 1 wherein the elastic portion comprises a silicone material.

13. The aircraft door of claim 12 wherein the elastic portion comprises a foam material.

14. The aircraft door of claim 1 wherein the elastic portion having a substantially zero poisson ratio.

15. The aircraft door of claim 1 wherein the edge portion comprises multiple edge segments.

16. An aircraft door adapted to substantially seal with a door frame, the aircraft door comprising:

an edge portion formed to be engagable with the door frame, the edge portion having a sealed position wherein the edge portion is engagable with a the door frame, the edge portion having an unsealed position wherein the edge portion is not engagable with the door frame;

a substantially rigid door body;

an elastic portion interposed between the door body and the edge portion, the elastic portion being selectively expandable and compressible for permitting movement of the edge portion between the sealed and unsealed positions;

an actuator device mechanically coupling the door body with the edge portion for selectively moving the edge portion between the sealed and unsealed positions, the actuator device comprising a shape memory metal wire having a predetermined transition temperature;

wherein the shape memory metal wire assuming a contracted state when above the transition temperature and the edge portion being sized and configured to be in the unsealed position; and

wherein the shape memory metal wire assuming an expanded state when below the transition temperature and the edge portion being sized and configured to be in the sealed position.

17. The aircraft door of claim 16 wherein the actuator device further comprises a heat source in thermal communication with the shape memory metal wire for selectively heating the shape memory wire above and below the transition temperature.

18. The aircraft door of claim 17 wherein the heat source comprises a thermal strip.

19. The aircraft door of claim 17 wherein the shape memory metal wire having first and second ends in thermal communication with the heat source.

20. The aircraft door of claim 19 wherein the shape memory metal wire having a wire body interposed between the first and second ends, the wire body being looped about the edge portion.

21. An aircraft door adapted to substantially seal with a door frame, the aircraft door comprising:

an edge portion formed to be engagable with the door frame, the edge portion having a sealed position wherein the edge portion is engaged with the door frame, the edge portion having an unsealed position wherein the edge portion is not engaged with the door frame;

a substantially rigid door body; and

an actuator device comprising a shape memory metal material mechanically coupling the edge portion to the door body and selectively moving the edge portion between the sealed and unsealed positions at a predetermined transition temperature of the material.

22. The aircraft door of claim 21 further comprises an elastic portion interposed between the door body and the edge portion, the elastic portion is selectively expandable and compressible for permitting movement of the edge portion between the sealed and unsealed positions.

23. The aircraft door of claim 22 wherein the elastic portion comprises a silicone material.

24. The aircraft door of claim 22 wherein the elastic portion comprises a foam material.

25. The aircraft door of claim 22 wherein the elastic portion having a substantially zero poisson ratio.

26. The aircraft door of claim 22 wherein the shape memory material is in slidable communication with the elastic portion.

27. The aircraft door of claim 22 wherein the actuator device is pre-strained to compress the elastic material when the actuator device is at the transition temperature.

28. The aircraft door of claim 21 wherein the actuator device assumes a contracted state when above the transition temperature and the edge portion is sized and configured to be in the unsealed position, the actuator device assumes an expanded state when below the transition temperature and the edge portion is sized and configured to be in the sealed position.

29. The aircraft door of claim 21 wherein the actuator device further comprises a heat source in thermal communication with the shape memory metal wire for selectively heating the shape memory wire above and below the transition temperature.

30. The aircraft door of claim 29 wherein the heat source comprises a thermal strip.

31. The aircraft door of claim 29 wherein the shape memory metal material has first and second ends in thermal communication with the heat source.

32. The aircraft door of claim 21 wherein the shape memory metal material comprises a shape memory metal wire.

33. The aircraft door of claim 32 wherein the shape memory metal wire has a wire body interposed between the first and second ends, the wire body is looped about the edge portion.

34. The aircraft door of claim 32 wherein the shape memory metal wire has a diameter of about 0.01 inches.

35. The aircraft door of claim 21 wherein the shape memory metal material is in slidable communication with the edge portion.

36. The aircraft door of claim 21 wherein the actuator device comprises a plurality of shape memory metal wires arrayed to collectively move the edge portion between the sealed and unsealed positions.

37. The aircraft door of claim 21 wherein the edge portion comprises multiple edge segments.