Cycled fiber lock for cross-functional totally dry optical fiber loose tube cable

• US 6,253,012 B1
• Filed: 02/10/1999
• Issued: 06/26/2001
• Est. Priority Date: 11/12/1998
• Status: Expired due to Term

• Current Assignee: Nexans Incorporated (Nokia Corporation)
• Original Assignee: Alcatel SA (Nokia Corporation)
• Inventors: Rosko, John C., Keller, Leslie P., Keller, David A.
• Primary Examiner(s): NGO, HUNG NHAT
• Application Number:
  US09/247,899
• Time in Patent Office: 867 Days
• Field of Search: 385/102-109, 385/112, 385/113
• US Class Current: 385/109
• CPC Class Codes: G02B 6/4436 Heat resistant
• CPC Class Codes: G02B 6/44384 the means comprising water blocking or hydrophobic materials G02B6/4439, G02B6/4479 take precedence

Abstract

A cable includes an optical fiber, a buffer tube having the optical fiber arranged therein, and a thermoset material for connecting the optical fiber to the buffer tube. The thermoset material will not melt or appreciably soften and will maintain basic elastomeric flexibility in a temperature range of −40 to 70 degrees Celsius. The thermoset material may be a flame-retardant silicone elastomer, base and curing agent, as well as a liquid rubber molded compound, which is not flame-retardant. The thermoset material allows for fiber helix movement as the cable expands and contracts from −40 to +70 degrees Celsius, and is cyclically placed for connecting the optical fiber to the buffer tube at intervals of about every ½ meter, as well as at intervals of about every 10 meters. The cable is an indoor/outdoor flame retardant cable also having a fiberglass yarn matrix and a jacket, wherein either the buffer tube, the fiberglass yarn matrix, the jacket, or a combination thereof, is made from an optimal blend of polyvinylidene fluoride (PVDF) and flame retardant polyvinyl chloride (FRPVC). The indoor/outdoor flame retardant cable may have trace amounts of water swellable powder particles sprinkled on the optical fiber arranged inside the buffer tube.

Claims

1. A cable comprising:

an optical fiber;

a buffer tube having the optical fiber arranged therein;

a thermoset material for frictionally-connecting the optical fiber to the buffer tube,

wherein the thermoset material is liquid rubber—

rubber molded compound, which is not flame-retardant, but is applied about every 0.5-30 meters.

2. A cable according to claim 1, wherein the thermoset material will not melt or appreciably soften or harden in a temperature range of −

40 to +85 degrees Celsius.

3. A cable according to claim 1, wherein the thermoset material will maintain basic elastomeric flexibility in a temperature range of −

40 to +70 degrees Celsius.

4. A cable according to claim 1, wherein the thermoset material is a flame-retardant silicone elastomer, base and curing agent that is easily removed from the fiber after drying.

5. A cable according to claim 1, wherein the thermoset material allows for fiber helix movement as the cable expands and contracts in a temperature range from −

40 to +70 degrees Celsius.

6. A cable according to claim 1, wherein the thermoset material is cyclically placed for connecting the optical fiber to the buffer tube at intervals.

7. A cable comprising:

an optical fiber;

a buffer tube having the optical fiber arranged therein;

a thermoset material for frictionally-connecting the optical fiber to the buffer tube,

wherein the low viscosity elastomer includes a 2-part mix of low viscosity material for dripping on the optical fiber.

8. A cable according to claim 7, wherein the thermoset material will melt or appreciably soften or harden in a temperature range of −

40 to +85 degrees Celsius.

9. A cable according to claim 7, wherein the thermoset material will maintain basic elastomeric flexibility in a temperature range of −

40 to +70 degree Celsius.

10. A cable according to claim 7, wherein the thermoset material is a flame-retardant silicone elastomer, base and curing agent that is easily removed from the fiber after drying.

11. A cable according to claim 7, wherein the thermoset material allows for fiber helix movement as the cable expands and contracts in a temperature range from −

40 to +70 degrees Celsius.

12. A cable according to claim 7, wherein the thermoset material is cyclically placed for connecting the optical fiber to the buffer tube at intervals.

13. A cable comprising:

an optical fiber;

a buffer tube having the optical fiber arranged therein;

a thermoset material for frictionally-connecting the optical fiber to the buffer tube,

wherein the thermoset material is cyclically placed for connecting the optical fiber to the buffer tube at intervals of about every 0.5-30 meters.

14. A cable according to claim 13, wherein the thermoset material will not melt or appreciably soften or harden in a temperature range of −

40 to +85 degrees Celsius.

15. A cable according to claim 13, wherein the thermoset material will maintain basic elastomeric flexibility in a temperature range of −

40 to +70 degrees Celsius.

16. A cable according to claim 13, wherein the thermoset material is a flame-retardant silicone elastomer, base and curing agent that is easily removed from the fiber after drying.

17. A cable according to claim 13, wherein the thermoset material allows for fiber helix movement as the cable expands and contracts in a temperature range from −

40 to +70 degrees Celsius.

18. A cable according to claim 13, wherein the thermoset material is cyclically placed for connecting the optical fiber to the buffer tube at intervals.

19. A cable comprising:

an optical fiber;

a buffer tube having the optical fiber arranged therein;

a thermoset material for frictionally-connecting the optical fiber to the buffer tube,

wherein the buffer tube is marked with indicia to indicate the locations of the thermoset material.

20. A cable according to claim 19, wherein the thermoset material will not melt or appreciably soften or harden in a temperature range of −

40 to +85 degrees Celsius.

21. A cable according to claim 19, wherein the thermoset material will maintain basic elastomeric flexibility in a temperature range of −

40 to +70 degrees Celsius.

22. A cable according to claim 19, wherein the thermoset material is a flame-retardant silicone elastomer, base and curing agent that is easily removed from the fiber after drying.

23. A cable according to claim 19, wherein the thermoset material allows for fiber helix movement as the cable expands and contracts in a temperature range from −

40 to +70 degrees Celsius.

24. A cable according to claim 19, wherein the thermoset material is cyclically placed for connecting the optical fiber to the buffer tube at intervals.

25. A cable comprising:

an optical fiber;

a buffer tube having the optical fiber arranged therein;

a thermoset material for frictionally-connecting the optical fiber to the buffer tube,

wherein the cable includes trace amounts of water swellable powder particles electrostatically sprinkled on the optical fiber arranged inside the buffer tube.

26. A cable according to claim 25, wherein the trace amounts of water swellable powder particles are less than 50 microns in diameter.

27. A cable according to claim 25, wherein the trace amounts of water swellable powder particles are applied on the optical fiber with about 0.10-1.0 grams per meter.

28. A cable according to claim 25, wherein the trace amounts of water swellable powder particles are less than 50 microns in diameter, and are applied on the optical fiber with about 0.10-1.0 grams per meter.

29. A cable according to claim 25, wherein the water swellable powder is made from a copolymer blend of polyacrylate and polyalcohol resins.

30. A cable according to claim 25, wherein the thermoset material will not melt or appreciably soften or harden in a temperature range of −

40 to +85 degrees Celsius.

31. A cable according to claim 25, wherein the thermoset material will maintain basic elastomeric flexibility in a temperature range of −

40 to +70 degrees Celsius.

32. A cable according to claim 25, wherein the thermoset material is a flame-retardant silicone elastomer, base and curing agent that is easily removed from the fiber after drying.

33. A cable according to claim 25, wherein the thermoset material allows for fiber helix movement as the cable expands and contracts in a temperature range from −

40 to +70 degrees Celsius.

34. A cable according to claim 25, wherein the thermoset material is cyclically placed for connecting the optical fiber to the buffer tube at intervals.

35. An indoor/outdoor flame-retardant cable, comprising:

an optical fiber;

a buffer tube having the optical fiber arranged therein;

a fiberglass yarn matrix having fiberglass yarns and being arranged about the buffer tube;

a jacket being arranged about the fiberglass yarn matrix;

either the jacket, the buffer tube, the fiberglass yarn matrix, or a combination thereof, is made from an optimal blend of flame retardant polyvinyl chloride (FRPVC) and polyvinylidene fluoride (PVDF) in a range of 30-60% of PVDF and 70-40% FRPVC; and

a plurality of cycled fiber locks, each made from a thermoset material for frictionally-connecting the optical fiber to the buffer tube.

36. An indoor/outdoor flame-retardant cable according to claim 35, wherein the thermoset material will not melt or appreciably soften or harden in a temperature range of −

40 to +70 degrees Celsius.

37. An indoor/outdoor flame-retardant cable according to claim 35, wherein the thermoset material will maintain basic elastomeric flexibility in a temperature range of −

40 to +70 degrees Celsius.

38. An indoor/outdoor flame-retardant cable according to claim 35, wherein the thermoset material is a flame-retardant silicone elastomer, base and curing agent.

39. An indoor/outdoor flame-retardant cable according to claim 35, wherein the thermoset material is Liquid Rubber—

Rubber Molded Compound (PMC-121/40, Parts A and B), which is not flame-retardant, but is applied about every 30 meters.

40. An indoor/outdoor flame-retardant cable according to claim 35, wherein the thermoset material allows for fiber helix movement as the cable expands and contracts in a temperature range from −

40 to +70 degrees Celsius.

41. An indoor/outdoor flame-retardant cable according to claim 35, wherein the low viscosity elastomer includes a 2-part mix of low viscosity material for dripping on the optical fiber.

42. An indoor/outdoor flame-retardant cable according to claim 35, wherein the plurality of cycled fiber locks are cyclically placed for connecting the optical fiber to the buffer tube at intervals.

43. An indoor/outdoor flame-retardant cable according to claim 35, wherein the plurality of cycled fiber locks are cyclically placed for connecting the optical fiber to the buffer tube at intervals of about every 0.5-30 meters.

44. An indoor/outdoor flame-retardant cable according to claim 35, wherein the buffer tube is marked with indicia to indicate the locations of the thermoset material.

45. An indoor/outdoor flame-retardant cable according to claim 35, wherein the cable includes trace amounts of water swellable powder particles electrostatically sprinkled on the optical fiber arranged inside the buffer tube.

46. An indoor/outdoor flame-retardant cable according to claim 45, wherein the trace amounts of water swellable powder particles are less than 50 microns.

47. An indoor/outdoor flame-retardant cable according to claim 45, wherein the trace amounts of water swellable powder particles are applied on the optical fiber with about 0.10-1.10 grams per meter.

48. An indoor/outdoor flame-retardant cable according to claim 45, wherein the trace amounts of water swellable powder particles are less than 50 microns, and are applied on the optical fiber with about 0.10-1.0 grams per meter.

49. An indoor/outdoor flame-retardant cable according to claim 45, wherein the water swellable powder is made from a copolymer blend of polyacrylate and polyalcohol resins.

50. A cable comprising:

an optical fiber;

a buffer tube having the optical fiber arranged therein;

a thermoset material for frictionally-connecting the optical fiber to the buffer tube,

wherein the cable further comprises;

a fiberglass yarn matrix having fiberglass yarns and being arranged about the buffer tube;

a jacket being arranged about the fiberglass yarn matrix; and

either the jacket, the buffer tube, the fiberglass yarn matrix, or a combination thereof, is made from an optimal blend of flame retardant polyvinyl chloride (FRPVC) and polyvinylidene fluoride (PVDF) in a range of 30-60% of PVDF and 70-40% FRPVC.

51. A cable comprising:

an optical fiber;

a buffer tube having the optical fiber arranged therein;

a thermoset material for frictionally-connecting the optical fiber to the buffer tube,

wherein the cable further comprises;

a fiberglass yarn matrix having fiberglass yarns and being arranged about the buffer tube;

a jacket being arranged about the fiberglass yarn matrix; and

either the jacket, the buffer tube, the fiberglass yarn matrix, or a combination thereof, is made from 100% polyvinylidene fluoride (PVDF).

52. A cable comprising:

an optical fiber;

a buffer tube having the optical fiber arranged therein;

a thermoset material for frictionally-connecting the optical fiber to the buffer tube,

wherein the cable is a loose tube cable having multiple buffer tubes, each buffer tube having a respective optical fiber and a respective thermoset material for frictionally-connecting the respective optical fiber to a respective buffer tube.

53. A cable according to claim 52, wherein the cable includes a central strength member having an overcoat;

and wherein the multiple buffer tubes are arranged about the central strength member.

54. A cable according to claim 53, wherein the central strength member and the overcoat are made of a UV cured low flame and smoke generation PVDF material.

55. A cable comprising:

an optical fiber;

a buffer tube having the optical fiber arranged therein;

a thermoset material for frictionally-connecting the optical fiber to the buffer tube,

wherein the thermoset material is dry to the touch after curing and can be easily peeled off the optical fiber.

56. A cable according to claim 55, wherein the thermoset material will not melt or appreciably soften or harden in a temperature range of −

40 to +85 degrees Celsius.

57. A cable according to claim 55, wherein the thermoset material will maintain basic elastomeric flexibility in a temperature range of −

40 to +70 degrees Celsius.

58. A cable according to claim 55, wherein the thermoset material is a flame-retardant silicone elastomer, base and curing agent that is easily removed from the fiber after drying.

59. A cable according to claim 55, wherein the thermoset material allows for fiber helix movement as the cable expands and contracts in a temperature range from −

40 to +70 degrees Celsius.

60. A cable according to claim 55, wherein the thermoset material is cyclically placed for connecting the optical fiber to the buffer tube at intervals.