Dielectric ribbon optical fiber cable

• US 5,384,880 A
• Filed: 12/03/1993
• Issued: 01/24/1995
• Est. Priority Date: 12/03/1993
• Status: Expired due to Fees

• Current Assignee: Alcatel NA Cable Systems Inc (Nokia Corporation)
• Original Assignee: Alcatel NA Cable Systems Inc (Nokia Corporation)
• Inventors: Black, Kevin, Webb, George, Keller, David A., Davidson, Frank
• Primary Examiner(s): Healy, Brian
• Application Number:
  US08/162,573
• Time in Patent Office: 417 Days
• Field of Search: 385/100, 385/109, 385/110, 385/111, 385/113, 385/114, 385/115
• US Class Current: 385/109
• CPC Class Codes: G02B 6/4403 with ribbon structure G02B6/4429, G02B6/4439, G02B6/4479 take precedence
• CPC Class Codes: G02B 6/4411 Matrix structure
• CPC Class Codes: G02B 6/443 Protective covering
• CPC Class Codes: G02B 6/4431 with provision in the protective covering, e.g. weak line, for gaining access to one or more fibres, e.g. for branching or tapping break-out terminations G02B6/4471
• CPC Class Codes: G02B 6/4432 with fibre reinforcements
• CPC Class Codes: G02B 6/4433 Double reinforcement laying in straight line with optical transmission element
• CPC Class Codes: G02B 6/44384 the means comprising water blocking or hydrophobic materials G02B6/4439, G02B6/4479 take precedence

Abstract

The optical fiber cable has a plurality of centrally located optical fiber ribbons. Carrying the optical fiber ribbons is a gel-filled plastic buffer tube. An adhesive layer is applied along the outside of the buffer tube and yarns extend in a contra-helical pattern over the adhesive. The yarns are impregnated with a gel for lubricating the contact points between the yarns and a longitudinally applied mylar tape layer. The mylar tape layer is coated with a thin layer of sealant which permits application of final polyethylene outer jacket provided for additional cable protection. Embedded within the outer jacket is a pair of diametrically opposed, longitudinally extending strength members.

Claims

1. An optical fiber cable comprised of:

a single, hollow buffer tube with a first water blocking gel-like compound and at least one optical fiber disposed therein;

at least one layer of yarn adhesively bonded to an outer portion of said buffer tube;

a second water blockable gel-like compound impregnating said at least one layer of yarn;

a tape layer applied over said at least one layer of yarn and said second water blockable gel-like compound;

a sealant compound applied over said tape layer;

a plastic jacket which encapsulates said tape layer and bonds to said sealant compound; and

two longitudinally extending strength members adjacent said tape layer and at least partially embedded in said jacket approximately 180 degrees apart.

2. A cable as described in claim 1, wherein said second water blockable gel-like compound impregnating said at least one layer of yarn has a viscosity lower than that of said sealant compound applied over said tape layer.

3. A cable as described in claim 1, wherein said at least one optical fiber is a plurality of optical fibers in a protective coating forming at least one optical fiber ribbon.

4. A cable as described in claim 1, wherein said at least one optical fiber is a stack of optical fiber ribbons.

5. A cable as described in claim 4, wherein said stack is helically twisted within said buffer tube.

6. A cable as described in claim 1, wherein said at least one layer of yarn comprises two contra-helically applied layers of yarns.

7. A cable as described in claim 1, wherein said at least one layer of yarn comprises strength yarns and water swellable yarns.

8. A cable as described in claim 1, further including at least one ripcord longitudinally disposed over said at least one layer of yarns.

9. A cable as described in claim 1, wherein said tape layer is longitudinally applied over said at least one layer of yarn and said second water blockable gel-like compound.

10. A cable as described in claim 1, wherein said tape layer is non-metallic.

11. A cable as described in claim 1, wherein said tape layer is a mylar tape layer.