Borescope comprising fluid supply system

• US 20050281520A1
• Filed: 06/16/2004
• Published: 12/22/2005
• Est. Priority Date: 06/16/2004
• Status: Active Grant

• Current Assignee: GE Inspection Technologies LP (General Electric Company)
• Original Assignee: GE Inspection Technologies LP (General Electric Company)
• Inventors: Lia, Raymond A., Karpen, Thomas W., Krauter, Allan I., Kehoskie, Michael P., Morse, Bradford, Von Felten, Kenneth
• Granted Patent: US 7,422,559 B2
• Time in Patent Office: Days
• US Class Current: 385/117
• CPC Class Codes: G01N 21/954 Inspecting the inner surface of hollow bodies, e.g. bores
• CPC Class Codes: G02B 23/2492 Arrangements for use in a hostile environment, e.g. a very hot, cold or radioactive environment

Abstract

A borescope device having an insertion tube, a camera head assembly, and a fluid supply system. The camera assembly includes through holes allowing fluid escape. The fluid supply system is controllable to force fluid through the through holes. The fluid supply system may be actuated to cool the camera head assembly.

Claims

1. A borescope comprising:

an insertion tube having a distal end;

at least one of an electrical conductor, a fiber optic bundle, and an articulation cable disposed within said insertion tube;

a camera head assembly disposed at said distal end of said insertion tube, said camera assembly having formed therein at least one fluid outlet opening;

a solid state image sensor disposed in said camera head assembly;

a lens disposed in said camera head assembly focusing an image onto said solid state image sensor; and

a fluid supply system supplying fluid to said camera assembly through said insertion tube, wherein said fluid escapes said camera assembly through said at least one fluid outlet opening.

2. The borescope or claim 1, further comprising a check valve disposed at said fluid outlet opening.

3. The borescope of claim 1, wherein said insertion tube includes a multi-layer insulating layer assembly.

4. The borescope of claim 1, wherein said insertion tube includes a wall of multi-layer construction, wherein one of said layers comprises porous fiberglass having a thermal conductivity of less than 0.50 BTU-in/(hr-ft²-F°

).

5. The borescope of claim 1, wherein said insertion tube includes a layer having a plurality of micropores formed throughout a length thereof.

6. The borescope of claim 1, wherein said insertion tube includes a polytetrafluoroethylene layer having a plurality of micropores formed throughout a length thereof, said micropores being formed with progressively higher density from a proximal end of said insertion tube to a distal end of said insertion tube.

7. The borescope of claim 1, wherein said borescope further includes a hand piece having a fluid input point, and wherein said hand piece is pressure sealed in such manner that fluid entering said fluid input point is forced though said insertion tube toward said camera head assembly.

8. The borescope of claim 1, wherein said borescope further includes a hand piece having a fluid input point, and wherein said fluid supply system includes a conduit extending from said fluid input point and terminating at a position within said insertion tube.

9. The borescope of claim 1, wherein said borescope further includes a hand piece having a fluid input point, and wherein said fluid supply system includes a conduit extending from said fluid input point through said insertion tube to said camera head assembly.

10. The borescope of claim 1, wherein said fluid delivered by said fluid supply system is a mixture of oxygen and nitrogen.

11. The borescope of claim 1, wherein said fluid delivered by said fluid supply system is carbon dioxide.

12. The borescope of claim 1, wherein said fluid delivered by said fluid supply system is a chlorofluorocarbon, which changes state at or before said camera head assembly

13. The borescope of claim 1, wherein said camera head assembly includes a metal canister housing camera component and a sleeve disposed about said canister, and wherein said at least one fluid exit hole is formed in said canister.

14. The borescope of claim 1, wherein said borescope further includes a bimetallic valve disposed at said fluid outlet opening.

15. A method for cooling a borescope camera assembly having a metal canister encasing electrical components of said camera assembly, said method comprising the steps of:

forming through holes in said canister; and

disposing a sleeve about said canister, said sleeve being configured in a coordinated manner with said canister so that air flowing outward from said through holes is directed to flow along an outer surface of said canister and;

forcing fluid into said canister in such manner that said fluid flows out of said through holes.

16. The method of claim 15, wherein said disposing step includes the step of disposing a sleeve about said canister.

17. The method of claim 15, wherein said forcing step includes the step of forcing a mixture of oxygen and nitrogen into said canister.

18. A borescope camera head assembly comprising:

a metal canister;

a sleeve disposed about said canister;

an image sensor and electrical circuitry disposed within said canister;

a plurality of through holes formed in a wall of said canister, wherein said sleeve and said canister are complimentarily formed with said canister so that fluid flowing out of said canister is directed along a surface of said canister.

19. The borescope of claim 18, wherein said sleeve is configured to be detachably attachable to said canister.

20. The borescope of claim 18, wherein said assembly further includes a lens disposed within said canister.

21. The borescope of claim 18, wherein said camera head assembly includes a head assembly to insertion tube interface, wherein a cooling fluid delivery conduit is received at said interface, and sealant is formed about said conduit so that cooling fluid losses external to said camera head assembly are reduced.

22. An insertion tube remote viewing device comprising:

an insertion tube having a wall and carrying at least one of an articulation cable, a fiber bundle, and an electrical conductor, wherein said wall is of a multilayer stacked construction;

a fluid supply system; and

a camera head assembly disposed at a distal end of said insertion tube, wherein said multilayer wall is devoid of a sealing layer and includes a microporous layer having micropores formed therein, and wherein fluid delivered by said fluid supply system escapes from said micropores of said microporous layer.

23. The device of claim 22, wherein said multilayer insertion tube wall further includes a non-sealing abrasion resistant wire braid layer disposed about said microporous layer.

24. The device of claim 22, wherein said multilayer insertion tube wall further includes a nonsealing monocoil, wherein said microporous layer is disposed about said monocoil.

25. The device of claim 22, wherein said microporous layer has a melting point of at least 500°

(degrees) Fahrenheit.

26. The device of claim 22, wherein said microporous layer consists of polytetrafluoroethylene.

27. The device of claim 22, wherein said micropores are formed with progressively higher density throughout a length of said insertion tube from a proximal end of said insertion tube to a distal end thereof.

28. An insertion tube remote viewing device comprising:

an insertion tube having a wall and carrying at least one of an articulation cable, a fiber bundle, and a wire bundle, wherein said wall is of a multilayer stacked up construction;

a fluid supply system; and

a camera head assembly disposed at a distal end of said insertion tube, wherein said multilayer wall of said insertion tube is devoid of material having a melting temperature lower than about 400°

(degrees) Fahrenheit and wherein said insertion tube remote viewing device is configured to receive fluid from said fluid supply system.

29. The insertion tube remote viewing device of claim 28, wherein said multilayer wall includes a layer selected from the group consisting of nonporous polytetrafluoroethylene, meta-phenelyneisophthalamide, and poly-paraphenylene terephthalamide.

30. The insertion tube remote viewing device of claim 28, wherein said multilayer wall includes a layer of nonporous polytetrafluoroethylene.

31. The insertion tube remote viewing device of claim 28, wherein said multilayer wall includes a layer selected from the group consisting of nonporous polytetrafluoroethylene, meta-phenelyneisophthalamide, and poly-paraphenylene terephthalamide, and wherein said multilayer further includes a layer of porous fiberglass having a thermal conductivity of less than 0.50 BTU-in/(hr-ft²-F°

).

32. An insertion tube remote viewing device comprising:

an insertion tube having a wall and carrying at least one of an articulation cable, a fiber bundle, and a wire bundle, wherein said wall is of a multilayer stacked up construction;

a camera head assembly disposed at a distal end of said insertion tube;

a solid state image sensor disposed in said camera head assembly;

an image processing circuit that processes image signals of said solid state image sensor, wherein said multilayer insertion tube includes at least one layer having a thermal conductivity of less than 0.50 BTU-in/(hr-ft²-F°

), and wherein said insertion tube remote viewing device is configured to receive fluid from a fluid supply system.

33. The insertion tube remote viewing device of claim 32, wherein said multilayer insertion tube comprises a layer of porous fiberglass having a thermal conductivity of less than 0.50 BTU-in/(hr-ft²-F°

), and a nonporous layer of material layered adjacent to said porous fiberglass layer.

34. The insertion tube remote viewing device of claim 32, wherein said multilayer insertion tube comprises a layer of porous fiberglass having a thermal conductivity of less than 0.50 BTU-in/(hr-ft²-F°

), and a layer of nonporous material layered adjacent said porous fiberglass layer said nonporous material selected from the group consisting of polytetrafluoroethylene, meta-phenelyneisophthalamide, and poly-paraphenylene terephthalamide.

35. An insertion tube remote viewing device comprising:

an insertion tube having a wall and carrying at least one of an articulation cable, a fiber bundle, and an electrical conductor;

a camera head assembly disposed at a distal end of said insertion tube, said camera head assembly having a head portion and including a solid state image sensor, said solid state image sensor being disposed in said head portion of said camera head assembly;

a thermal sensor producing a temperature-indicating signal disposed to sense a temperature of said camera head assembly;

circuitry receiving said temperature-indicating signal produced by said thermal sensor and processing said temperature indicating signal to output a fluid control signal for sending to a fluid supply system, wherein said insertion tube remote viewing device is configured to receive fluid from a fluid supply system.

36. The insertion tube remote viewing device of claim 35, wherein said thermal sensor is provided by a thermistor.

37. The insertion tube remote viewing device of claim 35, wherein said thermal sensor is provided by said solid state image sensor.

38. The insertion tube remote viewing device of claim 35, wherein said circuitry includes an image processing circuit which processes frames of image data in said processing of said output fluid control signal.

39. The insertion tube remote viewing device of claim 35, wherein said fluid flow control signal adjusts at least one of a pressure and a temperature of fluid supplied by said fluid supply system.

40. The insertion tube remote viewing device of claim 35, wherein said fluid supply system includes a fluid supply, and wherein said insertion tube remote viewing device is configured so that said fluid supply receives said fluid flow control signal.

41. The insertion tube remote viewing device of claim 35, wherein said circuitry in processing said output signal monitors a temperature signal produced by a thermistor.