Rotor blade stowing system

• US 5,868,351 A
• Filed: 05/23/1996
• Issued: 02/09/1999
• Est. Priority Date: 05/23/1996
• Status: Expired due to Term

• Current Assignee: Bell Helicopter Michigan Inc (Textron Inc)
• Original Assignee: Bell Helicopter Textron Incorporated (Textron Inc)
• Inventors: Baskin, Charles L., Stamps, Frank B., Zierer, Joe J., Covington, Cecil E., Shimek, Glenn
• Primary Examiner(s): Grant, William
• Application Number:
  US08/653,731
• Time in Patent Office: 992 Days
• Field of Search: 244/6, 244/7 R, 244/7 C, 244/12.4, 244/48, 244/49, 244/56, 244/66, 416/142 R, 416/142 A, 416/142 B, 416/143, 416/153, 416/141 R, 416/141 A
• US Class Current: 244/7.00R
• CPC Class Codes: B64C 27/50 Blades foldable to facilitate stowage of aircraft
• CPC Class Codes: B64C 29/0033 the propellers being tiltable relative to the fuselage

Abstract

Rotor blade stowing system for stowing rotor blades that conserves storage space without adding significant weight or cost to the aircraft. The system includes a rotary actuator disposed on a blade grip member. A rotor blade is pivotally connected to the blade grip member. The rotary actuator is operably coupled to a blade pivoting cam and a locking cam. The system includes a cam follower linkage which has a first end which includes a blade pivoting cam follower and a locking cam follower and a second end. The blade pivoting cam follower follows the blade pivoting cam. The locking cam follower follows the locking cam. The second end of the cam follower linkage is coupled to the blade grip member. The system includes a shaft rotatably coupled to the blade grip member, a locking linkage bell crank operably coupled to the shaft, a delay cam coupled to the blade grip member, and a locking linkage idler operably coupled to the locking linkage bell crank. The locking linkage idler includes a delay cam follower that follows the delay cam. The system includes a locking linkage which has a first end coupled to the locking cam and a second end coupled to the locking linkage idler.

Claims

1. A rotor blade stowing system for stowing a rotor blade comprising:

a rotary actuator for pivoting a rotor blade between folded and deployed positions, said blade being pivotally connected to a blade grip member, said rotary actuator being disposed on said blade, said rotary actuator being operably coupled to a blade pivoting cam and a locking cam, said blade pivoting cam having a shoulder portion, said locking cam having a detent;

a cam follower linkage having a first end and a second end, said first end of said cam follower linkage having a blade pivoting cam follower and a locking cam follower, said blade pivoting cam follower on said first end of said cam follower linkage following said blade pivoting cam, said locking cam follower on said first end of said cam follower linkage following said locking cam, said second end of said cam follower linkage being coupled to said blade grip member;

a locking linkage having a first end and a second end, said first end of said locking linkage being coupled to said locking cam;

a shaft rotatably coupled to said blade grip member;

a locking linkage bell crank operably coupled to said shaft;

a locking linkage idler operably coupled to said locking linkage bell crank and said second end of said locking linkage, said locking linkage idler having a delay cam follower;

a shaft support housing; and

a delay cam coupled to said shaft support housing with said shaft extending through said delay cam, said delay cam including an arcuate portion such that said delay cam follower of said locking linkage idler can follow said arcuate portion of said delay cam without causing rotation of said shaft.

2. The system of claim 1 further comprising a pitch angle locking assembly operably coupled thereto.

3. The system of claim 2 wherein said pitch angle locking assembly comprises a pitch angle locking bell crank operably coupled to said shaft, said pitch angle locking bell crank being operably coupled to a pitch angle locking pin through a pitch angle locking pin linkage.

4. The system of claim 3, wherein said pitch angle locking pin is slidably supported by a bracket coupled to said blade grip member.

5. The system of claim 3 wherein said pitch angle locking pin is received into an opening in a drive hub of a rotor assembly so as to prevent any variation in the pitch angle of said blade.

6. The system of claim 1 further comprising a blade locking assembly operably coupled thereto.

7. The system of claim 6 wherein said blade locking assembly comprises a blade locking bell crank operably coupled to said shaft, said blade locking bell crank being operably coupled to a blade locking pin through a blade locking assembly idler.

8. The system of claim 7 further comprising an over center mechanism that prevents said blade locking pin from inadvertently disengaging said blade.

9. The system of claim 7 wherein said blade locking pin releasably engages said blade such that a longitudinal axis of said blade locking pin is disposed in an angular relation with respect to a longitudinal axis of said blade grip member when said blade locking pin engages said blade.

10. The system of claim 1 wherein said shaft support housing is made of aluminum.

11. The system of claim 1 wherein said second end of said cam follower linkage is coupled to said blade grip member by a latch support housing that is coupled to said blade grip member.

12. The system of claim 11 wherein said latch support housing is made of titanium.

13. The system of claim 11 wherein said latch support housing comprises a first blade positioning member having a surface engageable with said blade when said blade is in a deployed position for positioning said blade at a desired deployment.

14. The system of claim 13 wherein said latch support housing further comprises a first blade contact member disposed between said first blade positioning member and said blade when said blade is in a deployed position such that said first blade contact member contacts said blade.

15. The system of claim 1 wherein said system further comprises an additional delay cam, said additional delay cam having an arcuate portion and being coupled to said blade grip member such that an additional delay cam follower on said locking linkage idler can follow said arcuate portion of said additional delay cam without causing rotation of said shaft.

16. The system of claim 1 wherein said locking linkage idler is operably coupled to said locking linkage bell crank by a bolt, said locking linkage idler rotating about the longitudinal axis of said bolt, said arcuate portion of said delay cam being contained in a circle centered on said longitudinal axis of said bolt.

17. The system of claim 16 wherein said longitudinal axis of said bolt is generally parallel to the longitudinal axis of said shaft.

18. The system of claim 1 further comprising an electronic sensor coupled to said delay cam follower of said locking linkage idler.

19. The system of claim 1 further comprising an additional blade pivoting cam, said additional blade pivoting cam having a shoulder portion and being operably coupled to said rotary actuator, said cam follower linkage that follows said additional blade pivoting cam, said locking cam being disposed between said blade pivoting cam and said additional blade pivoting cam.

20. The system of claim 1 further comprising an additional locking cam, said additional locking cam having a detent and being operably coupled to said rotary actuator, said cam follower linkage further comprising an additional locking cam follower on said first end of said cam follower linkage that follows said additional locking cam, said blade pivoting cam being disposed between said locking cam and said additional locking cam.

21. The system of claim 1 further comprising an adjustment element coupled to said locking linkage idler to adjust the relative position of said delay cam follower of said locking linkage idler with respect to said locking linkage bell crank.

22. The system of claim 1 wherein said rotary actuator comprises a drive motor operably coupled to a system of planetary gears, said system of planetary gears being operably coupled to said blade pivoting cam and said locking cam.

23. The system of claim 1 wherein said rotary actuator is disposed within a blade pivot pin which allows said blade to pivot about a longitudinal axis of said blade pivot pin, said rotary actuator being operably coupled to said blade pivoting cam and said locking cam so as to pivot said blade between deployed and folded positions.

24. The system of claim 1 wherein said blade has an advancing side and a following side, said advancing side of said blade advancing in the direction said blade pivots when said blade is being folded from a deployed position to a folded position, said following side of said blade following said advancing side of said blade when said blade is being folded from a deployed position to a folded position.

25. The system of claim 24 wherein said advancing side of said blade has coupled thereto a hinging portion of a fairing that covers said blade grip member, said hinging portion of said fairing being piano hinged with said fairing so as to allow for the opening of said hinging portion of said fairing to allow said blade to fold.

26. The system of claim 25 wherein said following side of said blade has coupled thereto an opening portion of a fairing that covers said blade grip member, said opening portion of said fairing being releasably mated with said fairing so as to allow for the opening of said opening portion of said fairing to allow said blade to fold.

27. The system of claim 1 wherein said locking cam is a dwell cam and said delay cam is a dwell cam.

28. A blade stowing mechanism for moving a rotor blade between folded and deployed positions, the mechanism comprising:

a blade tang receptacle carried by a blade grip, the blade tang receptacle for receiving a tang portion of the rotor blade;

a blade lock assembly for rigidly locking the tang portion in the blade tang receptacle;

a rotary actuator coupled between the tang portion of the rotor blade and the blade grip, the rotary actuator for pivoting the blade relative to the blade grip;

a locking cam carried by the rotary actuator and rotatable relative to the rotor blade;

a pitch lock assembly for selectively locking the rotor blade against a change in pitch angle;

a locking link bell crank pivotally carried on a shaft by the blade grip and operably coupled to the blade and pitch lock assemblies, the locking link bell crank including a delay cam follower following a delay cam;

a shaft support housing;

said delay cam being coupled to said shaft support housing with said shaft extending through said delay cam;

a blade pivoting link extending between and coupled to the locking cam and the blade grip, wherein rotation of the locking cam by the actuator causes selective rotation of the rotor blade relative to the blade grip; and

a locking link extending between and coupled to the locking cam and the delay cam, wherein rotation of the locking cam by the actuator selectively causes movement of the locking link, locking link bell crank, and actuation of the pitch lock and blade lock assemblies;

wherein rotation of the actuator in a first direction moves the locking link and locking link bell crank to lock the pitch lock assembly and unlock the blade lock assembly, further rotation of the actuator in the first direction causing the blade to disengage from the blade tang receptacle and pivot relative to the blade grip to the folded position.

29. The blade stowing mechanism according to claim 28 wherein the rotary actuator is a part of a pivot pin about which the rotor blade pivots between the folded and deployed positions.

30. The blade stowing mechanism according to claim 28 wherein the locking cam includes a detent and dwell portion to permit rotation of the actuator without movement of the blade pivoting link.

31. The blade stowing mechanism according to claim 30 further comprising a shoulder carried by the rotary actuator that selectively confines the blade pivoting link in the detent portion of the locking cam to pivot the rotor blade relative to the blade grip.

32. The blade stowing mechanism according to claim 28 wherein the delay cam is a dwell cam.

33. A blade stowing mechanism for moving a rotor blade between folded and deployed positions, the mechanism comprising:

a rotary actuator coupled between a tang portion of the rotor blade and a blade grip, the rotary actuator for pivoting the blade relative to the blade grip;

a blade lock assembly for locking the tang portion to the blade grip;

a locking cam carried by the rotary actuator and rotatable relative to the rotor blade;

a locking link bell crank pivotally carried on a shaft by the blade grip and operably coupled to the blade lock assembly, the locking link bell crank including a delay cam follower following a delay cam;

a shaft support housing;

said delay cam being coupled to said shaft support housing with said shaft extending through said delay cam;

a blade pivoting link extending between and coupled to the locking cam and the blade grip, wherein rotation of the locking cam by the actuator causes selective rotation of the rotor blade relative to the blade grip; and

a locking link extending between and coupled to the locking cam and the delay cam, wherein rotation of the locking cam by the actuator selectively causes movement of the locking link, locking link bell crank, and actuation of the blade lock assembly;

wherein rotation of the actuator in a first direction moves the locking link and locking link bell crank to lock the pitch lock assembly and unlock the blade lock assembly, further rotation of the actuator in the first direction causing the blade to disengage from and pivot relative to the blade grip to the folded position.

34. The blade stowing mechanism according to claim 33 wherein the rotary actuator is a part of a pivot pin about which the rotor blade pivots between the folded and deployed positions.

35. The blade stowing mechanism according to claim 33 wherein the locking cam includes a detent and dwell portion to permit rotation of the actuator without movement of the blade pivoting link.

36. The blade stowing mechanism according to claim 35 further comprising a shoulder carried by the rotary actuator that selectively confines the blade pivoting link in the detent portion of the locking cam to pivot the rotor blade relative to the blade grip.

37. The blade stowing mechanism according to claim 33 further comprising:

a pitch lock assembly for selectively locking the rotor blade against a change in pitch angle, the pitch lock assembly being coupled to the locking link bell crank for actuation prior to pivoting the rotor blade relative to the blade grip.

38. The blade stowing mechanism according to claim 33 further comprising:

a blade tang receptacle carried by the blade grip, the blade tang receptacle for receiving the tang portion of the rotor blade, the blade pivoting link being coupled to the blade tang receptacle.

39. The blade stowing mechanism according to claim 33 wherein the delay cam is a dwell cam.