Forming of cable splice closures

• US 4,654,474 A
• Filed: 07/08/1985
• Issued: 03/31/1987
• Est. Priority Date: 06/19/1985
• Status: Expired due to Term

• Current Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Original Assignee: Northern Telecom Limited (Nortel Networks Corporation)
• Inventors: Scott, James R., D'Aoust, Ronald R., Charlebois, Leonard J.
• Primary Examiner(s): Grimley, Arthur T.
• Assistant Examiner(s): NIMMO, MORRIS
• Application Number:
  US06/752,745
• Time in Patent Office: 631 Days
• Field of Search: 174/84 R, 174/88 R, 174/78, 174/72 R, 156/49
• US Class Current: 174/88.00R
• CPC Class Codes: H02G 1/145 Moulds
• CPC Class Codes: H02G 15/117 for multiconductor cables
• CPC Class Codes: H02G 15/196 having lapped insulation

Abstract

Forming an encapsulated splice region between cable ends in which the splices formed by connecting conductors together are laid onto the jacket of a cable and are sealed from one another. A layer of resilient tape is wrapped around the cable and over the sealing material to seat it tightly onto conductors leading to the splices. A molded encapsulation is then formed around the splice region and the resilient tape, still in resilient condition holds the tight seal onto the conductors and prevents moisture from within the cables from reaching the splices.

Claims

1. A method of forming an encapsulated splice region joining two cable ends comprising:

removing core surrounding material from end regions of two cables to provide end portions of core surroundng material and cable core regions projecting axially a certain distance beyond said end portions;

turning the conductors of said core regions so that they extend radially outwards from the cables;

locating the cable end portions and the end portions of core surrounding material close together and substantially in axial alignment with the conductors projecting from between the end portions;

connecting shields of the two cables together with a rigid axially extending grounding means and enclosing the grounding means within a seal;

surrounding the seal and the end portions of core surrounding material with a layer of stiffening material with conductor ends projecting radially beyond the stiffening material;

with the conductor ends electrically connected together to form splices from one cable to the other, individually enclosing each splice within a compressible deforamble sealing material which extends over the stiffening layer and onto the outer surface of each cable at each end of the stiffening layer and with the splices located radially outwards of the core surrounding material;

applying a layer of a resilient tape material around the deformable sealing material in a position over a portion of the conductors as they extend from their splices axially along the end portions of core surrounding material, the resilient tape material being longitudinally stretched as it is being applied to radially compress the compressibly deformable sealing material into intimate sealing contact with each conductor; and

forming a plastic molding encapsulation around the deformable sealing material and resilient tape material, and over cable portions at each axial end of the deformable sealing material, the encapsulation formed at a temperature insufficient to cause the resilient tape material to relax from its stretched condition.

2. A method according to claim 1, wherein the compressible deformable sealing material is formed by first and second layers of wrapped tape of the material, the first layer applied over the stiffening layer by overlapped wrappings of the tape, the splices then being placed in spaced positions upon the first layer, and the second layer being formed as overlapped tape wrappings over the first layer.

3. A method according to claim 2, wherein the deformable sealing material is a heat softenable material and the method comprises using the heat of molding of the encapsulation to soften the deformable sealing material to cause it to merge into an integral whole by the influence of heat obtained while encapsulating.

4. A method according to claim 1, comprising forming the seal surrounding the grounding means from overlapped wrappings of a heat softenable material around the cable end regions under the grounding means and further wrappings of heat softenable material over the grounding means.

5. A method according to claim 1, comprising locating a rigid elongate support means between the cables, the rigid support means displaced circumferentially around the cables from the grounding means and covered with a seal.

6. A method according to claim 5, comprising locating all the splices along an axial length of the two cables which is spanned by the grounding means and support means.

7. A method according to claim 3, wherein the core surrounding material has a softening temperature above that of the layers of deformable sealing material and the method comprises providing insufficient heat to cause bonding of the molding to the core surrounding material.

8. An assembly of two telecommunications cables disposed end-to-end with conductors of each cable core electrically connected each to one conductor of the other cable to form a conductor splice and in which:

shields of the two cables are connected together with a rigid axially extending grounding means which is enclosed within a seal;

a layer of stiffening material surrounds the seal and end portions of core surrounding material with conductors projecting radially beyond the stiffening material and having axially extending parts outside the end portion of at least one of the cables to dispose the splices radially outwards of core surrounding material with each splice individually closed within and sealed from other splices by a sealing material and with axially extending parts of the conductors enclosed within and sealed by said sealing material, said sealing material being compressibly deformable;

a layer of resilient tape material is wrapped around the sealing material in a position radially outward of a portion of the axially extending parts of the conductors, the resilient tape material being in a stretched resilient condition circumferentially of the sealing material to apply a radially inwards compressive force upon the sealing material and hold it positively in sealing contact with said conductor parts; and

a surrounding molded plastic encapsulation extends from the core surrounding material of one cable to the core surrounding material of the other.

9. An assembly according to claim 8, wherein the sealing material surrounding the splieces is merged into an integral whole.

10. An assembly according to claim 8, wherein the seal surrounding the grounding means is an integral whole.

11. An assembly according to claim 8, provided with a rigid elongate support means extending between the cables and spaced circumferentially around the cables from the grounding means, the support means also being covered by a seal.

12. An assembly according to claim 11, wherein all of the splices are located along an axial length of the cables which is spanned by the grounding means and support means.

13. An assembly according to claim 10, wherein the encapsulation and core surrounding material of the cables are unbonded.