Pressure sensitive work indicator

• US 7,649,469 B2
• Filed: 05/30/2007
• Issued: 01/19/2010
• Est. Priority Date: 05/30/2007
• Status: Expired due to Fees

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Smith, Eric M., Marsh, Joseph C.
• Primary Examiner(s): TWEEL JR, JOHN ALEXANDER
• Application Number:
  US11/755,615
• Publication Number:
  US 20080297343A1
• Time in Patent Office: 965 Days
• Field of Search: 340/665, 737/61, 737/62, 411/13
• US Class Current: 340/665
• CPC Class Codes: F16B 2200/95 with markings, colours, indicators or the like
• CPC Class Codes: F16B 31/02 for indicating the attainment of a particular tensile load or limiting tensile load apparatus for, or method of, determining value of torque or twisting moment for tightening a nut or other member similarly stressed G01L5/24
• CPC Class Codes: F16B 31/028 with a load-indicating washer or washer assembly
• CPC Class Codes: G01L 1/247 using distributed sensing elements, e.g. microcapsules along a single optical fibre G01L1/242
• CPC Class Codes: G01L 5/24 for determining value of torque or twisting moment for tightening a nut or other member which is similarly stressed

Abstract

Systems and methods for indicating applied manipulation pressure are disclosed. In one embodiment, a method for indicating applied manipulation pressure includes affixing a pressure sensitive material to a coupling component. The pressure sensitive material is capable of displaying visual indications that correspond to different levels of applied manipulation force. A manipulation force is applied to the component. Subsequently, the pressure sensitive material displays the visual indications. In a specific implementation, the method also includes stopping the application of manipulation force when one of the visual indications is displayed.

Claims

1. A method for indicating applied pressure, comprising:

affixing a pressure sensitive material to a coupling component, wherein the pressure sensitive material is configured to display a color of a first intensity that corresponds to a first threshold of a manipulation force, and display the color of a second intensity that corresponds to a second threshold of the manipulation force;

applying the manipulation force to the coupling component;

identifying the manipulation force as reaching the first threshold when the first intensity is displayed by the pressure sensitive material; and

identifying the manipulation force as reaching the second threshold when the second intensity is displayed by the pressure sensitive material.

2. The method of claim 1, further comprising stopping the manipulation force application when the first intensity or the second intensity is displayed by the pressure sensitive material.

3. The method of claim 1, wherein affixing the pressure sensitive material to the coupling component includes affixing the pressure sensitive material to a fluidic fitting, and applying the manipulation force includes applying the manipulation force to the fluidic fitting.

4. The method of claim 1, wherein the second intensity is greater than the first intensity, and wherein the second threshold of the manipulation force is greater in magnitude than the first threshold of the manipulation force.

5. The method of claim 1, wherein affixing the pressure sensitive material includes affixing a pressure sensitive material that includes first microcapsules that burst at the first threshold of the manipulation force to provide the color of the first intensity, and second microcapsules that burst at the second threshold of the manipulation force to provide the color of the second intensity.

6. The method of claim 1, wherein the coupling component is configured to receive a maximum manipulation force, and wherein the first threshold corresponds to a maximum manipulation force for tightening the coupling component to a terminal position, and the second threshold exceeds the maximum manipulation force for tightening the coupling component to the terminal position.

7. The method of claim 1, wherein applying the manipulation force includes applying torque pressure to the coupling component.

8. The method of claim 7, wherein the coupling component is configured to receive a maximum torque pressure, and wherein the first threshold corresponds to the maximum torque pressure for tightening the coupling component to a terminal position, and the second threshold exceeds the maximum torque pressure for tightening the coupling component to the terminal position.

9. The method of claim 1, wherein affixing the pressure sensitive material to the coupling component includes affixing a pressure sensitive material to a fastener, and wherein applying the manipulation force includes applying the manipulation force to the fastener.

10. The method of claim 1, further comprising selecting a pressure sensitive material configured to at least display the second intensity when the manipulation force is substantially equal to a force desired for proper installation of the component.

11. The method of claim 1, wherein the pressure sensitive material includes one of an oxygen-sensitive material and a microcapsule-embedded material.

12. A method for indicating applied pressure for a coupling component, comprising:

selecting a pressure sensitive paint for the coupling component, wherein the pressure sensitive paint is configured to display a first luminescence level when the component receives a first torque pressure, and display a second luminescence level when the coupling component receives a second torque pressure;

applying the pressure sensitive paint to the coupling component;

applying a torque pressure to the coupling component; and

identifying the applied torque pressure as reaching the first torque pressure when the first luminescence level is displayed by the pressure sensitive paint;

identifying the applied torque pressure as reaching the second torque pressure when the second luminescence level is displayed by the pressure sensitive paint,

wherein the second luminescence level is greater than the first luminescence level.

13. The method of claim 12, wherein the coupling component is a fluidic fitting component.

14. The method of claim 12, wherein the first torque pressure corresponds to a desired torque pressure, and the second torque pressure corresponds to an excessive torque pressure.

15. The method of claim 14, further comprising terminating the torque pressure when the first luminescence level or the second luminescence level is displayed.

16. The method of claim 12, wherein selecting a pressure sensitive paint includes selecting a pressure sensitive paint that includes oxygen-sensitive luminescent dye particles.

17. A system, comprising:

a coupling component configured to fluidly couple a first coupling component to a second coupling component; and

a pressure sensitive paint applied to an outer surface of the coupling component and configured to display a first luminescence level when a first threshold of the manipulation force is applied to the component, and display a second luminescence level when a second threshold of the manipulation force is applied to the component, and wherein the second threshold of the manipulation force is greater in magnitude than the first threshold of the manipulation force, wherein the first and second luminescence levels are produced by oxygen-sensitive luminescent dye particles.

18. The system of claim 17, wherein the first threshold or the second threshold of the manipulation force is substantially equal to a force desired for proper installation of the coupling component.

19. The system of claim 17, further comprising a sensor-equipped computer to detect the at least one luminescence level.

20. The system of claim 17, wherein the second threshold of the manipulation force exceeds a force desired for proper installation of the coupling component.