Forming of cable splice closures

• US 4,678,866 A
• Filed: 07/08/1985
• Issued: 07/07/1987
• Est. Priority Date: 07/08/1985
• Status: Expired due to Fees

• Current Assignee: Northern Telecom Limited (Nortel Networks Corporation)
• Original Assignee: Northern Telecom Limited (Nortel Networks Corporation)
• Inventors: Charlebois, Leonard J.
• Primary Examiner(s): NIMMO, MORRIS
• Application Number:
  US06/752,747
• Time in Patent Office: 729 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 15/196 having lapped insulation

Abstract

Forming an encapsulated splice region between cables in which conductors of one cable are electrically connected to conductors of the other cable to form splices. After electrically isolating splices from one another, a barrier layer is provided which extends axially across and beyond the splices onto the cables and then a plastic encapsulation is molded so as to enclose the barrier layer. The materials of the molding and barrier layer are such that they do not unite at any interfacial region between them. This construction makes it easier to open the splice region subsequently.

Claims

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

locating two cable end portions close together and substantially in axial alignment;

electrically connecting conductors of one cable with those of the other to form splices and sealing each individual splice within dielectric sealing material to electrically isolate it from other splices;

covering the splices by surrounding the cable end portions at each axial side of the splices with a barrier layer which extends also over the splices and between the cable end portions to enclose a region between the cable end portions; and

forming a plastic molded encapsulation extending around the cables and over the splices so as to enclose the barrier layer with the barrier layer preventing the encapsulation material from penetrating into the region between cable end portions and into regions of the splices, and the materials of the encapsulation and of the barrier layer being separate and distinct from one another at any interfacial regions of the materials.

2. A method according to claim 1, comprising sealing the splices from one another by enclosing each individual splice within a sealing material which extends around at least one of the cables;

and surrounding the sealing material with the barrier layer before forming the encapsulation.

3. A method according to claim 2, comprising forming the barrier layer by making overlapped wrappings of a tape material around the cable ends and over the splices, and applying the encapsulation material at a temperature to provide insufficient heat to cause any bonding of the molding to the jacket material.

4. A method according to claim 3, comprising providing two ends of the sealing material projecting axially beyond the barrier layer, the sealing material being a heat softenable material, the temperature of application of the encapsulation material being sufficient to soften the sealing material so as to fuse the encapsulation and sealing materials together at the two projecting ends of the sealing material and thus form a seal at each end.

5. A method according to claim 1, wherein the cables are gas pressurizable, the method comprising:

surrounding the cable ends and splices with a preformed barrier layer of substantially cylindrical configuration by locating the barrier layer in a position surrounding one of the cables before forming the splices and then moving the barrier layer axially of the cables into a final position surrounding at least one of the cables and axially at each side of the splices so as to bridge the splices and to form a chamber containing the splices; and

providing a seal between the encapsulation and jackets of the cable to enable the chamber to be pressurizable.

6. A method according to claim 5, comprising providing a plastically deformable means in a position surrounding each cable and disposing the barrier layer in its final position with its ends supported by the deformable means which axially flank the chamber.

7. An assembly of two telecommunications cables disposed with conductors of each cable electrically connected together to form splices with the splices sealed within dielectric sealing material so as to be electrically isolated from one another, a barrier layer extending over the splices, surrounding adjacent end portions of both cables axially at each side of the splices extending between the adjacent cable end portions to enclose a region between the end portions, and a molded plastic encapsulation extending over the cable end portions and enclosing the barrier layer, the encapsulation and barrier layer being separate and distinct from one another at any interfacial regions of the materials and said region between the cable end portions being free of encapsulation material.