Fiber optic closure with cable adapter spool

• US 5,825,961 A
• Filed: 10/31/1996
• Issued: 10/20/1998
• Est. Priority Date: 03/20/1995
• Status: Expired due to Term

• Current Assignee: 3M Company
• Original Assignee: PSI Telecommunications, Inc.
• Inventors: Smith, Donald J., Wilkins, Timothy A.
• Primary Examiner(s): Sanghavi, Hemang
• Application Number:
  US08/740,608
• Time in Patent Office: 719 Days
• Field of Search: 385/134-137, 174/72 R, 174/77 R, 174/93, 174/92
• US Class Current: 385/135
• CPC Class Codes: G02B 6/4444 Seals
• CPC Class Codes: G02B 6/4446 Cable boxes, e.g. splicing boxes with two or more multi fibre cables
• CPC Class Codes: G02B 6/4447 with divided shells G02B6/4448 takes precedence
• CPC Class Codes: G02B 6/4471 Terminating devices demountable connectors G02B6/3807; Cable clamps
• CPC Class Codes: G02B 6/4477 with means for strain-relieving to interior strengths element
• CPC Class Codes: G02B 6/44775 Cable seals e.g. feed-through cable seals integrated to the box seals G02B6/4444; pulling eyes G02B6/44465
• CPC Class Codes: H02G 15/007 Devices for relieving mechanical stress
• CPC Class Codes: H02G 15/013 Sealing means for cable inlets inlets for cables filled with, or surrounded by, gas or oil H02G15/32
• CPC Class Codes: H02G 15/113 Boxes split longitudinally in main cable direction
• CPC Class Codes: H02G 15/117 for multiconductor cables

Abstract

A fiber optic splice closure assembly has two end plate assemblies, and a closure base and a closure cover attached to the end plate assemblies. An adapter is secured within a cable entrance port in the end plate assembly to alter the end plate opening to accommodate a fiber optic cable. The adapter restrains the cable sheath against axial forces and provides a seal between the optical fiber cable, the adapter and the end plate assembly. A bracket assembly is provided to anchor the optical fiber cable strength member to the end plate assembly. The closure provides a mounting bar secured to said end plate assemblies proximate the closure base and a mounting platform secured to the mounting bar.

Claims

1. A splice closure assembly adapted for enclosing an optical fiber cable splice, which cable includes an optical fiber cable sheath, a strength member, and a plurality of optical fibers, the splice closure assembly comprising:

two end plate assemblies, at least one of which has an opening of a first diameter therein;

a closure base and a closure cover attached to said end plate assemblies;

an adapter spool secured within said opening in said end plate assembly, said adapter spool having an outer diameter matching said first diameter and having a cable entrance port having a second diameter for receiving the optical fiber cable therein;

said adapter spool further comprising;

means for contracting said outer diameter of said adapter spool to secure the optical fiber cable within said cable entrance port;

means for restraining the optical fiber cable sheath within the closure by applying radial force to the cable within said cable entrance port; and

means for distributing said radial force to the optical fiber cable.

2. A splice closure assembly according to claim 1, wherein said means for distributing said radial force comprises a high coefficient of friction tape which is as wide as said means for restraining said optical fiber cable sheath, said tape having a strip of adhesive applied longitudinally along a central portion of one side of said tape for facilitating cable wrapping and for providing a seal between succeeding layers of said tape, wherein said tape is wrapped around the optical fiber cable until the diameter of said wrapped cable is equivalent to said second diameter.

3. A splice closure assembly according to claim 1, wherein said means for restraining comprises an annular flange having a plurality of gripping teeth which extend radially inward toward the center of said cable entrance port, wherein said annular flange is integrally formed with said adapter spool and said teeth are displaced in an arcuate configuration for retaining said means for distributing said radial force to the optical fiber cable when said means for contracting is actuated, thus retaining the fiber optic cable sheath against axial loads.

4. The splice closure assembly according to claim 3, wherein said means for restraining further comprises at least two said annular flanges.

5. The splice closure assembly according to claim 1, wherein said means for restraining comprises a raised rib which extends toward the center of said cable entrance port, wherein said raised rib is integrally formed with said adapter spool and is displaced in an arcuate configuration for retaining said means for distributing said radial force to the optical fiber cable when said means for contracting is actuated, thus retaining the fiber optic cable sheath against axial loads.

6. The splice closure assembly according to claim 5, wherein said means for restraining further comprises at least two raised ribs located proximate a front end and a back end of said adapter spool.

7. A method for adapting a cable to an end plate assembly having a cable entrance port of a first diameter, the cable having a third diameter and having a sheath, the method for adapting comprising the steps of:

providing tape having a high coefficient of friction and having a narrow strip of adhesive applied to one side;

applying said adhesive side of said tape around said cable to form a seal between the cable and the tape;

providing an adapter spool capable of being expanded and contracted, the contracted adapter spool having a first diameter and one or more adapter spool cable entrance ports having a second diameter;

wrapping said tape around the cable until the diameter of said wrapped cable is equivalent to said second diameter;

wrapping said wrapped cable with a layer of mastic sealant around a strip around the longitudinal center of the neoprene tape of the wrapped cable;

placing said wrapped cable into an adapter spool cable entrance port of an expanded adapter spool;

contracting said adapter spool to exert radial force on said wrapped cable, wherein said wrapped cable is sealed and restrained within said cable entrance port of said contracted adapter spool and wherein said contracted adapter spool has a first diameter.

8. A splice closure assembly for enclosing an optical fiber cable splice, which cable includes an optical fiber cable sheath, a strength member, and a plurality of optical fibers, the splice closure assembly comprising:

an end plate assembly having an opening of a first diameter therein;

a closure cover secured to said end plate assembly;

an adapter spool secured within said opening in said end plate assembly, said adapter spool having an outer diameter matching said first diameter and having a cable entrance port having a second diameter for receiving the optical fiber cable therein;

said adapter spool further comprising;

means for contracting said adapter spool;

an annular flange having a plurality of gripping teeth which extends radially inward toward the center of said cable entrance port, wherein said annular flange is integrally formed with said adapter spool and said teeth are displaced in an arcuate configuration; and

a raised rib integrally formed with said adapter spool, wherein said rib extends toward the center of said cable entrance port and is displaced in an arcuate configuration.

9. A splice closure assembly according to claim 8, further comprising means for distributing radial force to the optical fiber cable.

10. A splice closure assembly according to claim 9, wherein said means for distributing said radial force comprises a high coefficient of friction tape which is as wide as said means for restraining said optical fiber cable sheath, said tape having a strip of adhesive applied longitudinally along a central portion of one side of said tape for facilitating cable wrapping and for providing a seal between succeeding layers of said tape, wherein said tape is wrapped around the optical fiber cable until the diameter of said wrapped cable is equivalent to said second diameter.

11. A splice closure assembly according to claim 10, wherein said annular flange and said rib are configured so as to retain said means for distributing radial force to the optical fiber cable when said means for contracting is actuated so as to retain the fiber optic cable sheath against axial loads.

12. A splice closure assembly according to claim 8, wherein when said means for contracting is actuated said annular flange and said rib operate to retain the optical fiber cable sheath against axial loads.

13. The splice closure assembly according to claim 8, further comprising at least two said annular flanges and at least two said raised ribs, wherein when said means for contracting is actuated said annular flanges and said ribs operate to retain the optical fiber cable sheath against axial loads.