Water blocked cable portion and methods of making same

• US 5,217,808 A
• Filed: 11/29/1989
• Issued: 06/08/1993
• Est. Priority Date: 11/29/1989
• Status: Expired due to Fees

• Current Assignee: Fitel USA Corporation
• Original Assignee: AT&T, Inc.
• Inventors: Cobb, Gary S.
• Primary Examiner(s): Ryan, Patrick J.
• Assistant Examiner(s): Gray, Jill M.
• Application Number:
  US07/443,300
• Time in Patent Office: 1,287 Days
• Field of Search: 428/392, 428/383, 428/375, 428/34.9, 350/96.23, 174/23 C, 174/23 R
• US Class Current: 428/392
• CPC Class Codes: G02B 6/443 Protective covering
• CPC Class Codes: G02B 6/44384 the means comprising water blocking or hydrophobic materials G02B6/4439, G02B6/4479 take precedence
• CPC Class Codes: G02B 6/4471 Terminating devices demountable connectors G02B6/3807; Cable clamps
• CPC Class Codes: G02B 6/4476 with heat-shrinkable elements
• CPC Class Codes: G02B 6/4479 Manufacturing methods of optical cables
• CPC Class Codes: Y10T 29/49865 by temperature differential [e.g., shrink fit]
• CPC Class Codes: Y10T 29/49885 with coating before or during assembling
• CPC Class Codes: Y10T 428/1328 Shrinkable or shrunk [e.g., due to heat, solvent, volatile agent, restraint removal, etc.]
• CPC Class Codes: Y10T 428/2933 Coated or with bond, impregnation or core
• CPC Class Codes: Y10T 428/2936 Wound or wrapped core or coating [i.e., spiral or helical]
• CPC Class Codes: Y10T 428/2944 Free metal in coating
• CPC Class Codes: Y10T 428/2947 Synthetic resin or polymer in plural coatings, each of different type
• CPC Class Codes: Y10T 428/2958 Metal or metal compound in coating
• CPC Class Codes: Y10T 428/2964 Artificial fiber or filament

Abstract

An optical cable portion (10), resident within a cable closure (14), is caused to receive a water blocking arrangement which is effective to prevent water, which enters an internal cable portion (24) through an unintended cut (21) in an outer jacket (18) of a cable portion (20), from entering an interior of the cable closure. A plurality of water blocking materials (30 and 32) are coaxially disposed about the outer jacket and a core tube (26) of the cable portion, respectively, and cooperate with a heat shrinkable plastic tube (34) which substantially covers the water blocking materials to prevent the movement of water from the internal cable portion past the water blocking materials.

Claims

1. A water blocked optical fiber cable portion, which comprises:

a core comprising at least one optical fiber;

a longitudinally extending tube in which said core is disposed and from which an end portion of said core extends;

a longitudinally extending inner jacket coaxially disposed about said tube and from which an end portion of the tube extends;

a longitudinally extending metallic shield coaxially disposed about said inner jacket;

means including a ground wire connected to said shield for establishing a ground connection to said shield;

a longitudinally extending outer jacket which is coaxially disposed about said metallic shield and from which an end portion of said metallic shield extends;

a water blocking material disposed about an outer surface of an end portion of said outer jacket adjacent to said end portion of said metallic shield;

a disc of plastic material disposed adjacent to said end portion of said metallic shield and having openings through which said tube and ground wire extend; and

a plastic membrane disposed about a cable end portion and in compressive engagement with said water blocking material and said disc wherein the compressive engagement of the plastic membrane is effective to provide a water blocking seal between a portion of an inner surface of said plastic membrane and an outer surface of said disc and between a portion of an inner surface of said plastic membrane and a portion of said outer surface of said outer jacket.

2. The optical fiber cable portion of claim 1, wherein said plastic membrane is a heat shrinkable plastic tube.

3. The optical fiber cable portion of claim 2, wherein said water blocking material is a water blocking tape.

4. The optical fiber cable portion of claim 1, further comprising a second water blocking material comprising a water blocking polyurethane polymer disposed about said disc adjacent to said outer jacket.

5. The optical fiber cable portion of claim 4, wherein said first water blocking material comprises a water blocking polyurethane polymer material.