Rotating shaft damping with electro-rheological fluid

Patent metadata

Field	Value
Publication number	US-9841077-B2
Application number	US-201414307715-A
Country	US
Kind code	B2
Filing date	Jun 18, 2014
Priority date	Jun 18, 2014
Publication date	Dec 12, 2017
Grant date	Dec 12, 2017

Abstract

Some examples of rotating shaft damping with electro-rheological fluid can be implemented as a method. At least a portion of a circumferential surface area of a portion of a rotorcraft rotating shaft is surrounded with multiple hollow members. Each hollow member includes an electro-rheological fluid having a viscosity that changes based on an electric field applied to the electro-rheological fluid. A vibration of the rotorcraft rotating shaft is controlled by changing the viscosity of the electro-rheological fluid in response to the electric field applied to the electro-rheological fluid.

First claim

The invention claimed is:

1. A method of damping vibrations in a rotorcraft rotating shaft, the method comprising:
surrounding at least a portion of a circumferential surface area of a portion of a rotorcraft rotating shaft with a plurality of hollow members, each hollow member including an electro-rheological fluid having a viscosity that changes based on an electric field applied to the electro-rheological fluid;
controlling a vibration of the rotorcraft rotating shaft by changing the viscosity of the electro-rheological fluid in response to the electric field applied to the electro-rheological fluid; and
controlling the vibration of the rotorcraft rotating shaft by controlling a stiffness of an electromagnetic bearing positioned between the rotorcraft rotating shaft and the plurality of follow members.

2. The method of claim 1 , wherein the plurality of hollow members include two substantially U-shaped hollow members.

3. The method of claim 2 , wherein the two U-shaped hollow members surround all of the circumferential surface area of the portion of the rotorcraft rotating shaft.

4. The method of claim 1 , wherein each hollow member is an elastomeric member.

5. The method of claim 1 , wherein controlling the vibration of the rotorcraft rotating shaft comprises:
monitoring the vibration of the rotorcraft rotating shaft;
determining a quantity of damping to counter the vibration; and
applying a quantity of the electric field to the electro-rheological fluid, the quantity of the electric field to change the viscosity of the electro-rheological fluid to provide the determined quantity of damping.

6. The method of claim 5 , further comprising positioning a network of wires in the electro-rheological fluid, wherein applying the quantity of the electric field to the electro-rheological fluid comprises applying the quantity of the electric field to the network of wires.

7. The method of claim 1 , wherein controlling the vibration of the rotorcraft rotating shaft comprises:
determining that the vibration of the rotorcraft rotating shaft is greater than an upper vibrational limit; and
increasing the electric field applied to the electro-rheological fluid, wherein the electric field increases the viscosity of the electro-rheological fluid to counter the vibration.

8. The method of claim 7 , further comprising:
determining that the vibration of the rotating shaft is less than the upper vibrational limit; and
decreasing the electric field applied to the electro-rheological fluid, wherein the electric field decreases the viscosity of the electro-rheological fluid.

9. A radial damper assembly comprising:
a ring-shaped outer housing;
a plurality of hollow members positioned within the outer housing to surround at least a portion of a circumferential surface area of a portion of a rotorcraft rotating shaft, each hollow member including an electro-rheological fluid having a viscosity that changes based on an electric field applied to the electro-rheological fluid;
a network of wires arranged in columns or rows of alternating polarity that are positioned in and distributed throughout the electro-rheological fluid; and
an electromagnetic bearing having a variable stiffness positioned between the plurality of hollow members and the rotorcraft rotating shaft.

10. The assembly of claim 9 , wherein the plurality of hollow members include two substantially U-shaped hollow members.

11. The assembly of claim 10 , wherein the two U-shaped hollow members surround all of the circumferential surface area of the portion of the rotorcraft rotating shaft.

12. The assembly of claim 9 , wherein each hollow member is an elastomeric member.

13. The assembly of claim 9 , further comprising an inner race positioned between the plurality of hollow members and the rotorcraft rotating shaft.

14. A radial damper system comprising:
a radial damper assembly comprising a plurality of hollow members surrounding at least a portion of a circumferential surface area of a portion of a rotorcraft rotating shaft, each hollow member including an electro-rheological fluid having a viscosity that changes based on an electric field applied to the electro-rheological fluid;
an electromagnetic bearing positioned between the plurality of hollow members and the portion of the rotorcraft rotating shaft, the electromagnetic bearing having a variable stiffness; and
a vibration control system to control a vibration of the rotating shaft by changing at least one of the viscosity of the electro-rheological fluid in response to the electric field applied to the electro-rheological fluid or the stiffness of the electromagnetic bearing.

15. The system of claim 14 , wherein the vibration control system comprises:
a vibration monitoring system to monitor the vibration of the rotorcraft rotating shaft; and
an electric field generation system to apply a quantity of electric field to the electro-rheological fluid, the quantity of the electric field to change the viscosity of the electro-rheological fluid to damp the vibration.

16. The system of claim 14 , wherein the plurality of hollow members include two substantially U-shaped elastomeric hollow members which surround all of the circumferential surface area of the portion of the rotorcraft rotating shaft.

17. The assembly of claim 9 , wherein the network of wires positioned in the electro-rheological fluid comprises at least one of straight wires, crooked wires, or a matrix arrangement of wires.

18. The system of claim 14 , further comprising a network of wires positioned in and distributed throughout the electro-rheological fluid.

19. A radial damper assembly comprising:
a ring-shaped outer housing; and
a plurality of hollow members positioned within the outer housing to surround at least a portion of a circumferential surface area of a portion of a rotorcraft rotating shaft, each hollow member including an electro-rheological fluid having a viscosity that changes based on an electric field applied to the electro-rheological fluid;
a network of wires positioned in the electro-rheological fluid;
a bearing positioned between the plurality of hollow members and the rotorcraft rotating shaft, wherein the bearing is an electromagnetic bearing having a variable stiffness.

20. The assembly of claim 19 , wherein the plurality of hollow members include two substantially U-shaped hollow members that surround all of the circumferential surface area of the portion of the rotorcraft rotating shaft.

21. The assembly of claim 19 , wherein each hollow member is an elastomeric member.

22. The assembly of claim 19 , further comprising an inner race positioned between the plurality of hollow members and the rotorcraft rotating shaft.

Assignees

• Bell Helicopter Textron Inc

Inventors

• Modrezejewski Brian S M
• Spears Steven

Classifications

• F16F13/30

  comprising means for varying fluid viscosity, e.g. of magnetic or electrorheological fluids · CPC title

• F16F2222/12

  Fluid damping · CPC title

• B64C27/12

  Rotor drives · CPC title

• F16C27/00

  Elastic or yielding bearings or bearing supports, for exclusively rotary movement (shock-damping bearings for watches or clocks G04B31/02) · CPC title

• F16F13/1427

  characterised by features of flexible walls of equilibration chambers; decoupling or self-tuning means · CPC title