Kit and method for converting a conductive cable closure to a fiber optic cable closure

• US 5,793,921 A
• Filed: 10/31/1996
• Issued: 08/11/1998
• Est. Priority Date: 03/20/1995
• Status: Expired due to Fees

• Current Assignee: 3M Company
• Original Assignee: PSI Telecommunications, Inc.
• Inventors: Smith, Donald J., Wilkins, Timothy A.
• Primary Examiner(s): Bovernick, Rodney B.
• Assistant Examiner(s): Sanghavi, Hemang
• Application Number:
  US08/741,608
• Time in Patent Office: 649 Days
• Field of Search: 385/134-137, 385/54, 385/94, 385/99, 385/100, 174/77 R, 174/87, 174/92, 174/93
• 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 fiber optic closure conversion kit for converting a splice closure assembly for enclosing an electrically-conductive cable splice into a splice closure assembly for enclosing an optical fiber cable splice, which splice closure assembly is provided with two end plate assemblies, at least one of which has an opening of a first diameter, and a closure base and a closure cover, the conversion kit comprising:

a mounting bar, having thereon assembled a fiber optic splice tray platform which is separated from said mounting bar by spacers;

an adapter spool, the adapter spool having a first diameter and one or more adapter spool cable entrance ports having a second diameter;

means for securing the mounting bar directly to at least one of the end plate assemblies;

means adapted to be rigidly coupled to said end plate assembly for anchoring an optical fiber cable strength member; and

means for restraining an optical fiber cable sheath relative to said means for anchoring.

2. A fiber optic closure conversion kit as in claim 1, the kit further comprising at least one of:

one or more buffer tube guides;

one or more stabilizer lugs; and

a fiber optic splice tray for retaining optical fibers.

3. A fiber optic closure conversion kit as in claim 1, the kit further comprising:

a two-piece anchoring assembly and a hose clamp for securing together said two-piece anchoring assembly, said two piece anchoring assembly comprising;

a cantilevered member having an anchoring platform;

and

a bracing member.

4. A fiber optic closure conversion kit as set out in claim 1, the kit further comprising a length of tape for application to the optical fiber cable.

5. A fiber optic closure conversion kit as set out in claim 4, wherein the tape has a high coefficient of friction and has a narrow strip of adhesive applied to one side for application onto the optical fiber cable.

6. A fiber optic closure conversion kit as set out in claim 4, wherein the tape is a mastic sealant tape.

7. A fiber optic closure conversion kit as set out in claim 1, wherein the means for securing comprises a mounting sleeve for receiving the mounting bar.

8. A fiber optic closure conversion kit as set out in claim 7, wherein the means for securing further comprises a mounting bracket for securing the mounting sleeve to the end plate assembly.

9. A method for converting a splice closure assembly for enclosing an electrically-conductive cable splice into a splice closure assembly for enclosing an optical fiber cable splice, which splice closure assembly is provided with two end plate assemblies, at least one of which has an opening of a first diameter, a closure base and a closure cover attached to said end plate assemblies, and wherein the cable has a third diameter and includes an optical fiber cable sheath, a strength member, and a plurality of optical fibers within a plurality of fiber optic buffer tubes, the method comprising:

securing a mounting bar, having thereon assembled a fiber optic splice tray platform which is separated from said mounting bar by spacers, to each end plate assembly;

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

providing an adapter spool, the adapter spool having a first diameter and one or more adapter spool cable entrance ports having a second diameter;

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

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

providing a layer of mastic sealant around a strip around the longitudinal center of said 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;

placing said contracted adapter spool into said opening of said end plate; and

securing said end plate within the closure assembly.

10. A method for converting a splice closure assembly of claim 9, further comprising:

securing one or more buffer tube guides to said mounting bar.

11. A method for converting a splice closure assembly of claim 9, wherein the splice closure assembly further comprises a two-piece anchoring assembly and a hose clamp for securing together said two-piece anchoring assembly, said two-piece anchoring assembly comprising a cantilevered member having an anchoring platform and a bracing member, the method further comprising the steps of:

securing the fiber optic cable strength member to said anchoring platform of said cantilevered member before the step of placing said wrapped cable into said adapter spool cable entrance port;

securing said bracing member to the end plate assembly proximate the opening in said end plate assembly; and

securing the cantilevered member to said bracing member using a hose clamp after the step of securing said bracing member to the end plate assembly and after the step of placing said contracted adapter spool into said opening of said end plate.

12. A method for converting a splice closure assembly of claim 9, further comprising:

inserting one or more stabilizer lugs into through-holes of the closure base to stabilize the closure base during conversion operations.

13. An apparatus for stabilizing a closure assembly to facilitate an operator working on the closure assembly, the closure assembly having a base and a cover, the base and the cover of the closure assembly including flanged sides extending along each side of the base and the cover, the flanged sides having a plurality of corresponding through-holes, the stabilizing apparatus comprising:

an elongated stabilizer lug having a threaded first end, said threads corresponding to said through-hole of said closure assembly, said lug having a length of at least half the diameter of the closure, wherein when one of said base and said cover is resting lengthwise on a work surface said first end of said lug is threadedly engaged into said through-hole in said flanged side of said one of said base and said cover and a second end of said lug extends perpendicularly from said flanged portion of said one of said base and said cover substantially to said work surface so as to stabilize said one of said base and said cover.

14. The apparatus for stabilizing a closure assembly as in claim 13, further comprising a plurality of said stabilizer lugs installed into said through-holes wherein at least one of said lugs is installed into a through-hole on each side of said one of said base and said cover to substantially inhibit the closure base from rocking while the operator is working on the closure.

15. The apparatus for stabilizing a closure assembly as in claim 13, wherein both ends of said stabilizer lug are threaded so as to allow either end to be used in threaded engagement with a through-hole.