GB2305024A

GB2305024A - A connector for establishing continuity of two ducts for telephone cables

Info

Publication number: GB2305024A
Application number: GB9617647A
Authority: GB
Inventors: Jean-Luc Campion; Alain Pecot
Original assignee: France Telecom SA
Current assignee: Orange SA
Priority date: 1995-08-25
Filing date: 1996-08-23
Publication date: 1997-03-26
Anticipated expiration: 2016-08-23
Also published as: GB9617647D0; FR2738084B1; DE19632476B4; GB2305024B; FR2738084A1; DE19632476A1

Description

1 Telephone Cable Duct Connector 2305024 The present invention relates to

a connector for establishing continuity between two ducts for telephone cables.

The current telephone network is making increasingly frequent use of fibre optic cables of considerable length between two connecting splices and the dependability and efficiency of which, combined with a substantial reduction in the bulk needed to place them, are such that fibre optic cables will henceforth and wherever possible replace the copper cables of the existing network.

This replacement has the advantage of making it possible to use existing civil engineering works containing copper cables of the previous generation, works which represent a major investment in the construction and establishment of such a network.

For conventional copper cables which are heavy and bulky, the crosssections of the underground ducts which accommodate them are of shorter length and are separated from one another by sunken chambers, the cables being connected within the chambers to appropriate connection or distribution boxes.

When it is desired to use the same ducts when replacing copper cables by fibre optic cables, after having removed the copper cables, or even using the available space within these ducts alongside the former cables which remain in place, then it is necessary to provide suitable connections at right-angles to the separating chambers to ensure the continuity of the sections of ducts which open out into each of these chambers. The fibre optic cable should be capable of being placed in position with no discontinuity, finihennore ensuring a mechanical protection of the fibre optic cable, which is naturally fragile and which, without special precautions, might be subjected to stresses prejudicial to their crossing each of these separating chambers.

The object of the present invention is to provide a connection of the above type which is easy to position, has a low friction coefficient in order not to impede the passage of the fibre optic cable through the connection and which provides satisfactory sealing tightness from one section of duct to another, through each separating chamber.

2 In accordance with the present invention there is provided a connector for use in establishing continuity between two telephone cable ducts by means of an interconnecting conduit, each of the ducts passing through an associated support to terminate at and be communicable with the inside of an intermediate chamber containing the conduit, the connector being in the form of a connecting socket having; a male portion engagable within the end of one of the ducts and a female portion adapted to be disposed in the chamber and applied against one of the support wherein; the male portion is adapted so that when engaged with said duct it is anchored therein and the female portion has an wdal seating into which an end part of the interconnecting conduit is received, and there is provided means to fix the end part of the interconnecting conduit in the seating.

The male portion can be anchored into a duct by use of an interference fit. The outside portion of the male part can have a grooved or notched surface which is co-operable with the inside wall of the duct.

The male portion may have an inside a)dal passage with a conical profile. An end of the wdal passage may be chamfered.

In the seating of the female portion there may be provided a split ring for reception of an end of the interconnecting conduit so that the end abuts a transverse shoulder at the bottom of the seating in the socket. The inside surface of the ring can have profiling in the form of anchoring notches for contact with the interconnecting conduit.

A seal may be fitted into the inner lateral wall of the seating and contactable with the outer surface of the interconnecting conduit.

If a split ring is not used then the female portion may be provided with a cylindrical skirt having profiling on its inner surface and a diameter that is substantially equal to that of the outer diameter of the interconnecting conduit. In this case the female portion comprises at least one apdal slot to give the female portion a relative elasticity in the transverse direction 3 and a collar surrounding the outside of the cylindrical skirt to hold it clamped against the interconnecting conduit. One or more seals may be interposed between the skirt and conduit. A nipple may be provided on the outside surface of the skirt contactable with the collar for maintaining the collar in a fixed position.

Further characteristic features of a connector for establishing continuity between telephone cable ducts, established according to the invention, will become further apparent from the ensuing description of a plurality of embodiments given by way of non-limitative indication, reference being made to the appended drawings, in which:

- Fig. I diagrammatically shows a conventional cable network comprising separating chambers into which emerge the opposing ends of a number of ducts two of which are selected for illustrative purposes only to be connected by a connector according to the present invention, - Fig. 2 is a perspective view of a separating chamber on a larger scale, - Fig. 3 is a cross-sectional view on an even larger scale through a connector in accordance with a first embodiment of the invention, - Figs. 4a, 4b and 4c illustrate another embodiment of the connector of the present invention and illustrating how the various parts of this connector are fitted, and Figs. 5a, 5b, 5c are views similar to Figs. 4a, 4b, 4c respectively but which relate to a further embodiment of the present invention.

In Fig. 1, reference numeral 2 diagrammaticaUy designates a portion of a telephone cable network comprising in particular successive separating chambers 3. Between these chambers, the cables 4 are housed in ducts 5 which open out into the separating chambers.

In conventional networks, the cables 4 are generafly made from copper and the portions of duct 5 between the separating chambers are of relatively short length. On the inside of each chamber, the cables which open out from the ducts are connected by splices acconnnodated injunction boxes (not shown).

In 'he currently employed practice, it is recommended to replace the conventional copper cables with fibre optic cables such as 6, which are generaffy unwound in considerable 4 lengths from coils 7, these fibre optic cables being introduced by suitable techniques into the portions of ducts 5 instead of or alongside existing copper cables already housed within these ducts.

However, with many types of fibre optic cables, their length can be substantially greater than that of the conventional copper cables and it is not necessary to make connecting splices in each separating chamber 3.

On the other hand, it is appropriate for these cables to be capable of passing through these chambers without any discontinuity, the passage from the end of one duct portion 5 to another in each chamber being performed by means of connecting tubes 8 the structure and positioning of which correspond to the present invention.

On a larger scale, Fig. 2 illustrates a separating charnber 3 with a connecting tube 8 disposed between the ends of two duct portions 5 which open out into the chamber substantially one opposite the other, making it possible to ensure continuity of these portions for the positioning of one or a plurality of fibre optic cables in particular.

Inside the chamber, it is advantageous to provide support members 9 for the tube 8 in order to avoid possible flexion or torsion stresses being applied to the fibre optic cables which pass through it.

On an even larger scale, Fig. 3 shows an embodiment of a connector according to the present invention for connection between the end of one duct portion 5 which opens out into the wall of a separating chamber 3 in the manner referred to hereinabove and the corresponding end of a connecting tube S.

In this first example, the connection is made by means of a socket 10 comprising a male part I I which engages axially into an end 12 of the duct 5, which is flush with the wall of the chamber 3, being held by a support member or mask 13, diagrammatically shown and of which the detail of the embodiment is not directly a factor which is important to the present invention.

The male part I I of the socket 10 has on the outside a diameter which is substantially equal to that of the end 12 of the duct 5 and is engaged into this latter with force. Advantageously, the outer surface of the part I I has notches 14 facilitating anchoring of the male part 11 of the socket in the duct, which can be in the form of a small-pitch screw thread or an appropriate arrangement of teeth.

Alternatively part 11 of the socket 10 could be glued against the inside surface of the end 12. Production of the connector by injection moulding of a suitable plastics material such as polyvinylchloride (PVC) which permits production with a low prime cost. Gluing is capable of being very easily performed against the duct since this is also conventionally made of PVC.

The anchoring of the socket 10 to the duct 5 thus provided allows satisfactory mechanical holding of the connector which by itself it produces at least partial sealing of the joint of the connector 10 and the duct 5. Preferably, a sealing-tight gasket 15 in the form of a flat or ring-shaped washer, is mounted between the end 12 of the duct 5 and a shoulder 16 of the socket 10 from which the male part 11 extends.

This same male part of the socket comprises an axial passage 17 through which the fibre optic cable (not shown) can pass. Advantageously this passage is of conical form. At the end of the socket the passage 17 has a rounded chamfer 18 to facilitate insertion of the cable 6 and to avoid any risk of a hooking engagement of the cable 6 on the socket before it reaches the connecting tube 8.

The socket 10 flirthermore, comprises a female part 19 defining an interior seating 20 which receives a seal in the form of 0-ring 21 disposed in an inner wall of the seating. On an opposite part the seating 20 has a cross-sectional widening 22 in which an anchoring ring 23 is fitted.

The ring 23 has an axial slot 24 and on its inner surface is provided with notches or teeth 25 for engaging the outer surface of the connecting tube 8 when the latter is pushed into the seating 20 of the socket until an end 26 of the tube 8 comes in contact with the bottom 27 of the seating. The elasticity of the ring 23 is provided by its axial slot 24 ensuring the necessary separation to allow penetration by the tube 8 allowing the notches 25 to become suitably anchored with the surface of the tube and subsequendy preventing any possibility of this latter being torn out.

6 In the another embodiment shown in Figs. 4a to 4c, in which identical reference numerals have been used to designate the same parts, the socket 10 again comprises a female part 19 defining an inner seating 20 but within which there is no interior ring as in the previous example.

In this case, the female part 19 takes the form of a cylindrical skirt 28, the inside diameter of which is substantially equal to the outside diameter of the connecting tube 8. This skin advantageously comprises notches 28a on its interior surface and has a slot 29 giving it the necessary elasticity to accommodate forced penetration by the end 26 of the connecting tube 8 until the latter abuts the end 27 of the seating 20. A tight seal between the tube 8 and the female part 19 is once again provided by the gasket in the form of the 0-ring 2 1.

In this second embodiment, the connection between the socket 10 and connecting tube 8 is maintained by virtue of a collar 30 which clamps the cylindrical skirt 28 of the socket by the outside, thereby encouraging the notches 28a provided on the inside surface of the skirt to be anchored to the outer surface of the tube 8. Advantageously, the collar 30 has a groove 31 in its interior surface for engagement with a nipple 32 provided in the outer surface of the skirt in order to ensure that the collar is held in place.

In Fig. 4a, the socket 10 is shown with its male part 11 positioned in the end 12 of the duct 5 and the connecting tube 8 and the clamping collar 30 are shown remote from the socket 10.

In Fig. 4b, the tube 8 is pushed into the skirt 28 of the female part 19 until the end 26 abuts the end 27 of the seating 20, the slot 29 imparting on this skirt the elasticity needed to tolerate this engagement.

In Fig. 4c, the clamping collar 30 is placed in a position around the outside of the skirt 28 to clamp the slot 29 together and prevent disengagement of the assembly.

Figs. 5a to Sc shows a finther embodiment of the present invention.

7 In this embodiment the tube 8 has an outer surface ringed by grooves 33 and ribs 34 distributed along the length of the tube.

The sealing-tight gasket 21, fitted inside the seating 20 of the socket 10, as provided for in the embodiment shown in figures 4a-c is dispensed with and is replaced by one and preferably two ring seals 35 and 36 directly fitted into the surface of the tube 8 and positioned along with the tube 8 into the seating 20 in order to obtain the desired tight seal.

Thus, a connection is established between the ends of two ducts in a chamber provided for passage of the telephone cable network which is of simple design and offers reliability and efficiency, by ensuring a high degree of mechanical protection of that portion of the cable passing through the chamber. The connection is particularly usefid during subsequent operations within this chamber particularly during the installation or removal of other cables.

The proposed solution is simple to implement and is of limited cost. Furthermore, the sealing-tightness obtained proves satisfactory, allowing the ducts to be pressurised once they have been connected.

Of course, it goes without saying that the invention is not confined to the embodiments more particularly described hereinabove with reference to the appended drawings; on the contrary, it embraces all possible alternative ernbodiments thereof 8

Claims

PATENT CLAIMS

1. A connector for use in establishing continuity between two telephone cable ducts by means of an interconnecting conduit, each of the ducts passing through an associated support to terminate at and be communicable with the inside of an intermediate chamber containing the conduit, the connector being in the form of a connecting socket having; a male portion engagable within the end of one of the ducts and a female portion adapted to be disposed in the chamber and applied against one of the support whereem.

the male portion is adapted so that when engaged with said duct it is anchored therein and the female portion has an axial seating into which an end part of the interconnecting conduit is received, and there is provided means to fix the end part of the interconnecting conduit in the seating.

2. A connector in accordance with claim 1, wherein when the male portion is engaged with the end of one of the ducts it forms an interference fit.

3. A connector in accordance with claim 1 or 2, characterised in that the male portion of the socket comprises on the outside a grooved or notched surface co-operable with the inside wall of the end of the duct.

4. A connector in accordance with claims 1, 2 or 3, characterised in that the male portion comprises on the inside an axial passage which is preferably conical in profile.

5. A connector in accordance with claim 4, wherein an end of the axial passage at an end of the male portion enterable with one of the ducts has a chamfer.

9

6. A connector in accordance with any one of claims 1 to 5, characterised in that the seating of the female portion contains a split ring for reception of an end of the interconnecting conduit so that the end abuts a transverse shoulder provided in the bottom of the seating in the socket.

7. A connector in accordance with claim 6, characterised in that the inside surface of the split ring comprises profiling in the form of anchoring notches for contact with the interconnecting conduit.

8. A connector in accordance with any one of claims 1 to 7, characterised in that a seal is fitted into the inner lateral wall of the seating and contactable with the outer surface of the interconnecting conduit.

9. A connector in accordance with any one of claims 1 to 5, characterised in that the female portion comprises a cylindrical skirt having profiling in its inner surface and of a diameter which is substantially equal to that of the outer diameter of the interconnecting conduit, the female portion comprising at least one wdal slot to impart a relative elasticity in the transverse direction and a collar surrounding the outside of this cylindrical skirt to hold it clarnped against the interconnecting conduit with the interposition of at least one seal.

10. A connector in accordance with claim 8, characterised in that the cylindrical skirt is provided in its outer surface with a nipple contactable with the collar for maintaining the clamping collar in a fixed position.

11. A connector as substantially described herein with reference to and as illustrated in any one or more of figures 3), 4 a-c and 5 a-c of the accompanying drawings.