Submarine cable having a centrally located tube containing optical fibers

• US 5,463,711 A
• Filed: 07/29/1994
• Issued: 10/31/1995
• Est. Priority Date: 07/29/1994
• Status: Expired due to Term

• Current Assignee: AT&T Submarine Systems, Inc. (Johnson Controls International plc)
• Original Assignee: AT&T IPM Corp. (AT&T, Inc.)
• Inventors: Chu, Tek-Che
• Primary Examiner(s): FONT, FRANK G
• Application Number:
  US08/282,355
• Time in Patent Office: 459 Days
• Field of Search: 385/100, 385/101, 385/109, 385/113, 385/114, 174/70 R
• US Class Current: 385/101
• CPC Class Codes: G02B 6/4416 Heterogeneous cables
• CPC Class Codes: G02B 6/4427 Pressure resistant cables, e.g. undersea cables

Abstract

A submarine optical fiber cable adapted for use in shallow-water submarine applications having the economy of non-armored cables with the robustness of armored cables is disclosed. The optical fiber cable comprises a plurality of longitudinally extending strength members arranged in a single layer around a single longitudinally extending central tube in a substantially close fitting manner. Disposed within the central tube is at least one optical fiber. In an illustrative example of the invention, six galvanized steel strength members are arranged in a close fitting manner around a hermetically sealed central steel tube, where the tube and the strength members have substantially identical outside diameters, so as to form a strong and stable shell. Plastic water-blocking material is disposed in the interstices between the strength members and the tube. Insulated conductors are disposed in grooves formed between adjacent strength members. An longitudinally extending annular plastic jacket is disposed about the strength members.

Claims

1. An optical fiber cable, comprising:

a longitudinally extending central tube;

six cylindrically-shaped longitudinally extending steel strength members helically wound around said longitudinally extending central tube in a substantially close fitting manner, wherein said longitudinally extending central tube and each of said cylindrically-shaped longitudinally extending steel strength members have substantially identical outside diameters, so as to form a single layered shell;

at least one optical fiber disposed within said longitudinally extending central tube; and

a water-blocking material disposed in interstices between said cylindrically-shaped longitudinally extending strength members and said longitudinally extending central tube.

2. The optical fiber cable of claim 1 wherein said longitudinally extending central tube is hermetically sealed.

3. The optical fiber cable of claim 1 wherein each of said cylindrically-shaped longitudinally extending strength members comprises a metal selected from the group consisting of steel, copper, or aluminum.

4. The optical fiber cable of claim 1 wherein each of said cylindrically-shaped longitudinally extending strength members comprises galvanized improved plow steel.

5. The optical fiber cable of claim 1 further including an elastomeric material contacting and surrounding said at least one optical fiber disposed within said longitudinally central extending tube.

6. The optical fiber cable of claim 5 wherein said elastomeric material substantially fills said longitudinally extending central tube.

7. The optical fiber cable of claim 1 further including an annular jacket disposed around said cylindrically-shaped longitudinally extending strength members.

8. The optical fiber cable of claim 7 wherein said annular jacket comprises a material selected from the group consisting of medium density polyethylene, high density polyethylene, or thermosetting resins.

9. The optical fiber cable of claim 1 further including a plurality of electrical conductors disposed in grooves between adjacent ones of said cylindrically-shaped longitudinally extending strength members.

10. The optical fiber cable of claim 9 wherein said conductors are wound in a helical lay about said cylindrically-shaped longitudinally extending strength members.

11. The optical fiber cable of claim 10 wherein said electrical conductors are insulated.

12. The optical fiber cable of claim 1 wherein said at least one optical fiber is disposed within said longitudinally extending central tube in a configuration selected from the group consisting of bundles or ribbons.

13. The optical fiber cable of claim 1 wherein said at least one optical fiber is disposed within said longitudinally extending central tube in a loose arrangement.

14. An optical fiber cable, comprising:

a longitudinally extending central tube;

six cylindrically-shaped longitudinally extending steel strength members helically wound around said longitudinally extending central tube in a substantially close fitting manner, wherein said longitudinally extending central tube and each of said cylindrically-shaped longitudinally extending steel strength members have substantially identical outside diameters, so as to form a single layered shell;

at least one optical fiber disposed within said longitudinally extending central tube; and

a plurality of electrical conductors disposed in grooves between adjacent ones of said cylindrically-shaped longitudinally extending strength members.

15. The optical fiber of claim 14, wherein said electrical conductors are insulated.

16. The optical fiber cable of claim 14 wherein said longitudinally extending central tube is hermetically sealed.

17. The optical fiber cable of claim 14 wherein each of said cylindrically-shaped longitudinally extending strength members comprises a metal selected from the group consisting of steel, copper, or aluminum.

18. The optical fiber cable of claim 14 wherein each of said cylindrically-shaped longitudinally extending strength members comprises galvanized improved plow steel.

19. The optical fiber cable of claim 14 further including an elastomeric material contacting and surrounding said at least one optical fiber disposed within said longitudinally central extending tube.

20. The optical fiber cable of claim 19 wherein said elastomeric material substantially fills said longitudinally extending central tube.

21. The optical fiber cable of claim 14 further including an annular jacket disposed around said cylindrically-shaped longitudinally extending strength members.

22. The optical fiber cable of claim 21 wherein said annular jacket comprises a material selected from the group consisting of medium density polyethylene, high density polyethylene, or thermosetting resins.

23. The optical fiber cable of claim 14 wherein said conductors are wound in a helical lay about said cylindrically-shaped longitudinally extending strength members.

24. The optical fiber cable of claim 14 wherein said at least one optical fiber is disposed within said longitudinally extending central tube in a configuration selected from the group consisting of bundles or ribbons.

25. The optical fiber cable of claim 14 wherein said at least one optical fiber is disposed within said longitudinally extending central tube in a loose arrangement.

26. The optical fiber cable of claim 14 further including a water-blocking material disposed in interstices between said cylindrically-shaped longitudinally extending strength members and said longitudinally extending central tube.

27. An optical fiber cable, comprising;

a longitudinally extending central tube;

six cylindrically-shaped longitudinally extending steel strength members helically wound around said longitudinally extending central tube in a substantially close fitting manner, wherein said longitudinally extending central tube and each of said cylindrically-shaped longitudinally extending steel strength members have substantially identical outside diameters, so as to form a single layered shell; and

at least one optical fiber disposed within said longitudinally extending central tube;

wherein said at least one optical fiber is disposed within said longitudinally extending central tube in a loose arrangement.

28. The optical fiber cable of claim 27 wherein said longitudinally extending central tube is hermetically sealed.

29. The optical fiber cable of claim 27 wherein each of said cylindrically-shaped longitudinally extending strength members comprises a metal selected from the group consisting of steel, copper, or aluminum.

30. The optical fiber cable of claim 27 wherein each of said cylindrically-shaped longitudinally extending strength members comprises galvanized improved plow steel.

31. The optical fiber cable of claim 27 further including an elastomeric material contacting and surrounding said at least one optical fiber disposed within said longitudinally central extending tube.

32. The optical fiber cable of claim 31 wherein said elastomeric material substantially fills said longitudinally extending central tube.

33. The optical fiber cable of claim 27 further including an annular jacket disposed around said cylindrically-shaped longitudinally extending strength members.

34. The optical fiber cable of claim 33 wherein said annular jacket comprises a material selected from the group consisting of medium density polyethylene, high density polyethylene, or thermosetting resins.

35. The optical fiber cable of claim 27 further including a water-blocking material disposed in interstices between said cylindrically-shaped longitudinally extending strength members and said longitudinally extending central tube.

36. The optical fiber cable of claim 27 further including a plurality of electrical conductors disposed in grooves between adjacent ones of said cylindrically-shaped longitudinally extending strength members.

37. The optical fiber cable of claim 36 wherein said conductors are wound in a helical lay about said cylindrically-shaped longitudinally extending strength members.

38. The optical fiber cable of claim 37 wherein said electrical conductors are insulated.