Eccentrically adjusted rotating scissor pitch control link

Patent metadata

Field	Value
Publication number	US-11560224-B2
Application number	US-202016738623-A
Country	US
Kind code	B2
Filing date	Jan 9, 2020
Priority date	Jan 9, 2020
Publication date	Jan 24, 2023
Grant date	Jan 24, 2023

Abstract

An adjustable control link for transferring rotor shaft rotation to a rotating swashplate, the adjustable control link includes an elongate element rotatable with the rotor shaft, the elongate element having a first end. A structure has an opening and a second end. At least one cam component is disposed within the opening and is rotatable relative to the structure about a central axis of the opening. A pin is configured to couple the elongate element to the at least one cam component. The pin is eccentrically rotatable about the central axis to move the first end of the elongate element relative to the second end of the structure.

First claim

What is claimed is:

1. An adjustable control link for transferring rotor shaft rotation to a rotating swashplate, the control link comprising:
an elongate element rotatable with the rotor shaft, the elongate element having a first end;
a structure having an opening and a second end;
at least one cam component disposed within the opening and rotatable relative to the structure about a central axis of the opening;
a pin configured to couple the elongate element to the at least one cam component, wherein the pin is eccentrically rotatable about the central axis to move the first end of the elongate element relative to the second end of the structure, wherein the rotation of the cam component is configured to move the elongate element eccentrically relative to the structure.

2. The adjustable control link of claim 1 , wherein the pin is mounted to the at least one cam component at a position offset from the central axis.

3. The adjustable control link of claim 2 , wherein the pin is radially offset from the central axis.

4. The adjustable control link of claim 2 , wherein the pin is laterally offset from the central axis.

5. The adjustable control link of claim 1 , wherein the structure further comprises:
a first sidewall;
a second sidewall; and
a body extending between the first sidewall and the second sidewall;
wherein the opening is disposed in the first and second sidewalls and the pin extends between the first and second sidewalls so as to dispose the elongate element therebetween.

6. The adjustable control link of claim 5 , wherein the first sidewall and the second sidewall converge at the second end of the structure.

7. The adjustable control link of claim 5 , wherein a mating element is defined at an end of at least one of the first sidewall and the second sidewall, the at least one cam component being mounted to the mating element.

8. The adjustable control link of claim 1 , wherein the at least one cam component includes a flange and at least one primary engagement feature is formed at a periphery of the flange.

9. The adjustable control link of claim 8 , wherein further comprising a locking mechanism selectively mounted to the at least one cam component to restrict rotation of the at least one cam component about the central axis.

10. The adjustable control link of claim 1 , wherein the structure includes at least one marking and the at least one cam component includes an indicator movable into alignment with the at least one marking to indicate an angle of the elongate member relative to the structure.

11. A rotor control system for use with a rotor and an airframe comprising:
a rotor shaft rotatable about a rotor axis;
a rotating swashplate;
at least one primary pitch control link associated with the rotor shaft;
at least one secondary pitch control link coupled to rotating swashplate to control a position of the at least one primary pitch control link, wherein the at least one secondary pitch control link includes a scissor control link adjustable to control a length of the secondary pitch control link;
wherein the scissor control link further comprises:
at least one elongate element coupled to the at least one primary pitch control link, the elongate element having a first end;
a structure having an opening and a second end;
at least one cam component disposed within the opening and rotatable relative to the structure about a central axis of the opening; and
a pin configured to couple the elongate element to the at least one cam component, wherein the pin is eccentrically rotatable about the central axis to move the first end of the elongate element relative to the second end of the structure, and wherein the rotation of the cam component is configured to move the elongate element eccentrically relative to the structure.

12. The rotor control system of claim 11 , wherein the scissor control link transmits rotation of the rotor shaft to the rotating swashplate.

13. The rotor control system of claim 11 , wherein the scissor control link is adjustable to control an angle between the at least one secondary pitch control link and the at least one elongate element.

14. The rotor control system of claim 13 , wherein the pin is mounted to the at least one cam component at a position offset from the central axis.

15. The rotor control system of claim 13 , wherein the structure further comprises:
a first sidewall;
a second sidewall; and
a body extending between the first sidewall and the second sidewall.

16. The rotor control system of claim 15 , wherein the first sidewall and the second sidewall converge at a first end of the structure.

17. The rotor control system of claim 15 , wherein a mating element is defined at an end of at least one of the first sidewall and the second sidewall, the at least one cam component being mounted to the mating element.

18. An aircraft comprising a rotor, an airframe and the rotor control system of claim 11 , wherein the rotor control system is configured for use with the rotor and the airframe.

19. The aircraft of claim 18 , further comprising a second rotor coaxial with the rotor, wherein the rotor and the second rotor rotate in opposite directions about the rotor axis.

Assignees

• Lockheed Corp

Inventors

• Cox John C

Classifications

• B64C27/10

  arranged coaxially · CPC title

• B64C27/605 Primary

  including swash plate, spider or cam mechanisms · CPC title

• B64C27/80

  for differential adjustment of blade pitch between two or more lifting rotors · CPC title