Coupling system for fiber optic cable using folded tape

Patent metadata

Field	Value
Publication number	US-9581777-B2
Application number	US-201313852810-A
Country	US
Kind code	B2
Filing date	Mar 28, 2013
Priority date	Mar 28, 2013
Publication date	Feb 28, 2017
Grant date	Feb 28, 2017

Abstract

A fiber optic cable includes a tube, a stack of fiber optic ribbons twisting along a lengthwise axis through the tube, and water-blocking tape positioned at least partially around the stack, between the stack and the tube. The water-blocking tape is folded such that an elevated portion of the water-blocking tape is raised. As the stack twists along the lengthwise axis of the tube, corners of the stack interface with the elevated portion to provide intermittent frictional coupling between the stack and the tube.

First claim

What is claimed is:

1. A fiber optic cable, comprising:
a tube having an interior;
a stack of fiber optic ribbons extending through the interior of the tube, wherein the stack twists along a lengthwise axis of the tube;
water-blocking tape positioned at least partially around the stack in the interior of the tube, between the stack and the tube, wherein the water-blocking tape is folded such that an elevated portion of the water-blocking tape is raised toward a lengthwise center of the interior of the tube,
wherein, as the stack twists along the lengthwise axis of the tube, at a position along the length of the cable in which a first cross-sectional dimension of the stack is aligned with the elevated portion, the stack interfaces with the elevated portion to provide frictional coupling between the stack and the tube, and
wherein, at another position along the length of the cable in which a second cross-sectional dimension of the stack is aligned with the elevated portion, the stack has less frictional coupling with the tube.

2. The cable of claim 1 , wherein the first cross-sectional dimension includes a corner of the stack, which, when aligned with the elevated portion, compresses the water-blocking tape against the interior of the tube.

3. The cable of claim 2 , wherein the second cross-sectional dimension includes a side of the stack between corners, which, when aligned with the elevated portion, does not pin the water-blocking tape to the interior of the tube.

4. The cable of claim 3 , wherein frictional coupling of the first cross-sectional dimension to the interior of the tube by way of the elevated portion of water-blocking tape is at least twice that of the second cross-sectional dimension.

5. The cable of claim 4 , wherein frictional coupling of the first cross-sectional dimension to the interior of the tube by way of the elevated portion of water-blocking tape is at least ten times that of the second cross-sectional dimension.

6. The cable of claim 3 , wherein, for a 30 meter length, the net force to pull the stack from the tube is at least 0.05 N per optical fiber in the stack facilitated by the frictional coupling provided by the water-blocking tape.

7. The cable of claim 6 , wherein, for a 30 meter length, the net force to pull the stack from the tube is at least 0.1 N per optical fiber in the stack.

8. The cable of claim 7 , wherein, for a 30 meter length, the net force to pull the stack from the tube is less than 1.0 N per optical fiber in the stack.

9. The cable of claim 1 , wherein the water blocking tape is folded on a lateral edge of the tape.

10. The cable of claim 1 , wherein the interior of the tube is round the elevated portion covers an arc of at least 15-degrees of the interior.

11. The cable of claim 10 , wherein the interior of the tube is round the elevated portion covers an arc of at least 30-degrees of the interior.

12. The cable of claim 11 , wherein the interior of the tube is round the elevated portion covers an arc of less than 90-degrees of the interior.

13. The cable of claim 1 , wherein the interior of the tube is round and the water blocking tape has an average width that is greater than 120% of the interior perimeter of the tube.

14. The cable of claim 1 , wherein the ribbon stack has more than four corners around the exterior periphery of the ribbon stack.

15. The cable of claim 1 , wherein the fold elevates the water-blocking tape such that the elevated portion extends at least 350 micrometers from the interior of the tube toward the center of the tube when uncompressed by the ribbon stack.

16. The cable of claim 15 , wherein interaction with the first cross-sectional dimension of the stack compresses the elevated portion to less than 200 micrometers from the interior of the tube toward the center of tube.

17. A fiber optic cable, comprising:
a tube having an interior;
an optical element comprising optical fibers extending through the interior of the tube, wherein the optical element twists along a lengthwise axis of the tube;
tape positioned at least partially around the optical element in the interior of the tube, between the optical element and the tube, wherein the tape is folded such that an elevated portion of the tape is raised toward a lengthwise center of the interior of the tube,
wherein, as the optical element twists along the lengthwise axis of the tube, at a position along the length of the cable in which a first cross-sectional dimension of the optical element is aligned with the elevated portion, the optical element interfaces with the elevated portion to provide frictional coupling between the optical element and the tube, and
wherein, at another position along the length of the cable in which a second cross-sectional dimension of the optical element is aligned with the elevated portion, the optical element has less frictional coupling with the tube.

18. The cable of claim 17 , wherein, for a 30 meter length, the net force to pull the optical element from the tube is at least 0.05 N per optical fiber in the optical element facilitated by the frictional coupling provided by the tape.

19. The cable of claim 17 , wherein the interior of the tube is round the elevated portion covers an arc of at least 15-degrees of the interior.

20. A method of manufacturing a cable, comprising steps of:
positioning a water-blocking tape around a stack of fiber optic ribbons;
folding the water-blocking tape such that layers of the tape overlay and contact one another to form a fold;
twisting the stack;
extruding a tube around the stack and the folded water-blocking tape, wherein the water-blocking tape is positioned at least partially around the stack in the interior of the tube, between the stack and the tube, wherein the water-blocking tape is folded such that an elevated portion of the water-blocking tape is raised toward a lengthwise center of the interior of the tube,
wherein, as the stack twists along the lengthwise axis of the tube, at a position along the length of the cable in which a first cross-sectional dimension of the stack is aligned with the elevated portion, the stack interfaces with the elevated portion to provide frictional coupling between the stack and the tube, and
wherein, at another position along the length of the cable in which a second cross-sectional dimension of the stack is aligned with the elevated portion, the stack has less frictional coupling with the tube.

Assignees

• Corning Cable Sys Llc
• Corning Optical Communications LLC

Inventors

• Baucom James Lee
• Lail Jason Clay
• Mccollough William Welch
• Seddon David Alan

Classifications

• G02B6/448

  Ribbon cables · CPC title

• Y10T29/49908

  Joining by deforming · CPC title

• G02B6/4403 Primary

  with ribbon structure (G02B6/4429, G02B6/4439, G02B6/4479 take precedence) · CPC title

• G02B6/4494

  Physics · mapped topic

• G02B6/449

  Twisting · CPC title