Dual layer buffer tube

Patent metadata

Field	Value
Publication number	US-11592633-B2
Application number	US-202016803070-A
Country	US
Kind code	B2
Filing date	Feb 27, 2020
Priority date	Sep 5, 2019
Publication date	Feb 28, 2023
Grant date	Feb 28, 2023

Abstract

A buffer tube for an optical fiber cable provided by the present disclosure includes an optical fiber ribbon stack, a first layer, a second layer, an optical fiber cable, a central strength member, a plurality of buffer tubes, a water blocking layer, and a sheath and plurality of rip cords. The first layer is an inner layer of the buffer tube. The first layer is made of a soft material. The soft material of the first layer is one of low smoke zero halogen, thermoplastic elastomers and thermoplastic polyurethane. The second layer is an outer layer of the buffer tube. The second layer surrounds the first layer. The second layer is made of a hard material. The hard material of the second layer is one of polypropylene, polybutylene terephthalate, and nylon.

First claim

What we claim is:

1. A buffer tube for an optical fiber cable, comprising:
a first layer, wherein the first layer is an inner layer of the buffer tube, wherein the first layer is made of a soft material; and
a second layer, wherein the second layer is an outer layer of the buffer tube, wherein the second layer surrounds the first layer, wherein the second layer is made of a hard material, wherein the second layer is characterized by crush resistance of 700 Newton per 10 centimetres.

2. The buffer tube as claimed in claim 1 , wherein the soft material of the first layer is one of low smoke zero halogen, thermoplastic elastomers and thermoplastic polyurethane.

3. The buffer tube as claimed in claim 1 , wherein the hard material of the second layer is one of polypropylene, polybutylene terephthalate, and nylon.

4. The buffer tube as claimed in claim 1 , wherein the buffer tube further comprises an optical fiber ribbon stack, wherein the optical fiber ribbon stack is packed inside the buffer tube, wherein the optical fiber ribbon stack comprises a plurality of optical fiber ribbons, wherein each of the optical fiber ribbon of the optical fiber ribbon stack comprises a plurality of optical fibers.

5. The buffer tube as claimed in claim 1 , wherein the first layer is characterized by shore hardness, wherein shore hardness of the first layer is in a range of 20 shore D to 40 shore D.

6. The buffer tube as claimed in claim 1 , wherein the second layer is characterized by shore hardness, wherein shore hardness of the second layer is in a range of 40 shore D to 80 shore D.

7. The buffer tube as claimed in claim 1 , wherein the first layer of the buffer tube reduces stress on a plurality of optical fibers, wherein the first layer reduces micro bend losses on the plurality of optical fibers.

8. The buffer tube as claimed in claim 1 , wherein the first layer of the buffer tube is characterized by thickness, wherein thickness of the first layer is in a range of 0.1 millimetre to 0.4 millimetre.

9. The buffer tube as claimed in claim 1 , wherein the crush resistance of 700 Newton per 10 centimetres sustains compressive tension and stress on the optical fiber cable.

10. The buffer tube as claimed in claim 1 , wherein the second layer of the buffer tube is characterized by thickness in a range of 0.2 millimetre to 0.5 millimetre.

11. A buffer tube for an optical fiber cable, comprising:
a first layer, wherein the first layer is an inner layer of the buffer tube, wherein shore hardness of the first layer is in a range of 20 shore D to 40 shore D; and
a second layer, wherein the second layer is an outer layer of the buffer tube, wherein the second layer surrounds the first layer, wherein shore hardness of the second layer is in a range of 40 shore D to 80 shore D,
an optical fiber ribbon stack, wherein the optical fiber ribbon stack is packed inside the buffer tube, wherein the optical fiber ribbon stack comprises a plurality of optical fiber ribbons, wherein each of the optical fiber ribbons of the optical fiber ribbon stack comprises a plurality of optical fibers.

12. The buffer tube as claimed in claim 11 , wherein the first layer is made of a soft material, wherein the soft material of the first layer is one of low smoke zero halogen, thermoplastic elastomers and thermoplastic polyurethane.

13. The buffer tube as claimed in claim 11 , wherein the second layer is made of a hard material, wherein the hard material of the second layer is one of polypropylene, polybutylene terephthalate, and nylon.

14. The buffer tube as claimed in claim 11 , wherein the first layer of the buffer tube is characterized by thickness, wherein thickness of the first layer is in a range of 0.1 millimetre to 0.4 millimetre.

15. The buffer tube as claimed in claim 11 , wherein the second layer is characterized by crush resistance of 700 Newton per 10 centimetres.

16. The buffer tube as claimed in claim 11 , wherein the second layer of the buffer tube is characterized by thickness in a range of 0.2 millimetre to 0.5 millimetre.

Assignees

• Sterlite Tech Ltd

Inventors

• Kumar Sravan
• Kondapalli Hemanth
• Sahoo Kishore Chandra

Classifications

• G02B6/4403 Primary

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

• G02B6/443 Primary

  Protective covering · CPC title