Armored fiber optic assemblies and methods of forming fiber optic assemblies
View Patent ↗Cables have dielectric armor with an armor profile that resembles conventional metal armored cable. The dielectric armor provides additional crush and impact resistance for the optical fibers and/or fiber optic assembly therein. The armored cables recover substantially from deformation caused by crush loads. Additionally, the armored fiber optic assemblies can have any suitable flame and/or smoke rating for meeting the requirements of the intended space.
1. An armored fiber optic assembly, comprising:
a fiber optic assembly having at least one optical fiber; and
a dielectric armor surrounding the fiber optic assembly, the dielectric armor having an armor profile with an outside diameter, wherein
when the dielectric armor is subjected to a crush load along a crush direction that reduces a crush dimension of the assembly from the outside diameter to less than 62 percent of the outside diameter, the cable assembly recovers when the crush load is released so that the crush dimension increases to at least 70 percent of the outside diameter.
2. The armored fiber optic assembly of claim 1 , wherein the at least one optical fiber comprises at least twelve optical fibers.
3. The armored fiber optic assembly of claim 1 , wherein when the dielectric armor is subjected to a crush load along a crush direction that reduces the crush dimension of the assembly from the outside diameter to less than 62 percent of the outside diameter, the cable assembly recovers so that the crush dimension increases to at least 74 percent of the outside diameter.
4. The armored fiber optic assembly of claim 1 , wherein the crush load is at least 8000 Newtons.
5. The armored fiber optic assembly of claim 1 , wherein the armored fiber optic assembly has a median separation in the range of about 0.1-1.5 millimeters between the fiber optic assembly and an interior of the dielectric armor.
6. The armored fiber optic assembly of claim 1 , wherein the dielectric armor comprises an inner layer and an outer layer.
7. The armored fiber optic assembly of claim 6 , wherein the inner layer has a continuous annular cross-section.
8. The armored fiber optic assembly of claim 6 , wherein the inner layer comprises a PVC.
9. The armored fiber optic assembly of claim 6 , wherein the armored fiber optic assembly satisfies ICEA S-83-596-2001.
10. The armored fiber optic assembly of claim 6 , wherein after the crush load is released, the at least one optical fiber has a delta attenuation due to the crush load of less than 0.4 decibels at 1550 nanometers.
11. The armored fiber optic assembly of claim 6 , wherein the armor profile has a pitch P between about 5 millimeters and about 30 millimeters and a groove length that is between about 20 percent and 80 percent of the pitch P.
12. The armored fiber optic assembly of claim 6 , wherein the at least one optical fiber comprises at least twelve optical fibers.
13. The armored fiber optic assembly of claim 6 , wherein the at least one optical fiber comprises at least twenty-four optical fibers.
14. The armored fiber optic assembly of claim 6 , wherein the inner layer has a modulus of elasticity of about 1200 MPa or greater.
15. The armored fiber optic assembly of claim 6 , wherein the dielectric armor has an outside diameter in the range of 8-15 millimeters.
16. The armored fiber optic assembly of claim 15 , wherein the inner layer is a PVC and the outer layer is a PVC.
17. The armored fiber optic assembly of claim 1 , wherein the armor profile has a pitch P between 5 millimeters and 30 millimeters and a groove length that is between 20 percent and 80 percent of the pitch P.
18. The armored fiber optic assembly of claim 17 , wherein the dielectric armor comprises an inner layer with a Shore D hardness and an outer layer with a Shore D hardness that is lower than that of the inner layer.
19. An armored fiber optic assembly, comprising:
a fiber optic assembly having at least one optical fiber; and
a dielectric armor surrounding the fiber optic assembly, the dielectric armor having an armor profile with an outside diameter, wherein
when the dielectric armor is subjected to a crush load along a crush direction that reduces a crush dimension of the assembly from the outside diameter to less than 58 percent of the outside diameter, the cable assembly recovers when the crush load is released so that the crush dimension increases to at least 70 percent of the outside diameter.
20. The armored fiber optic assembly of claim 19 , wherein when the dielectric armor is subjected to a crush load along a crush direction that reduces the crush dimension of the assembly from the outside diameter to less than 58 percent of the outside diameter, the cable assembly recovers so that the crush dimension increases to at least 72 percent of the outside diameter.
21. The armored fiber optic assembly of claim 19 , wherein the armored fiber optic assembly has a median separation in the range of about 0.1-1.5 millimeters between the fiber optic assembly and an interior of the dielectric armor.
22. The armored fiber optic assembly of claim 19 , wherein the dielectric armor comprises an inner layer with a Shore D hardness and an outer layer with a Shore D hardness that is lower than that of the inner layer.
23. The armored fiber optic assembly of claim 22 , wherein the inner layer has a continuous annular cross-section.
24. The armored fiber optic assembly of claim 23 , wherein the dielectric armor has an outside diameter in the range of 8-15 millimeters.
25. The armored fiber optic assembly of claim 1 , wherein the armor profile is an undulating shape along the length of the armor.
26. The armored fiber optic assembly of claim 19 , wherein the armor profile is an undulating shape along the length of the armor.