GB2171220A

GB2171220A - Optical fibre cable terminator

Info

Publication number: GB2171220A
Application number: GB08603676A
Authority: GB
Inventors: Roger Graham Smith; Peter Christian Shann
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-02-15
Filing date: 1986-02-14
Publication date: 1986-08-20
Also published as: GB8503902D0; GB8603676D0

Abstract

A terminal device, for an optical cable having a fibre optic core 8 within a protective sleeving, comprises a tubular member 12 adapted to receive, surround and support an end part of the core 8, a hollow member 1 for locating said tubular member 12, in a manner such that a space 2 which surrounds said tubular member 12 is left between said hollow member and said tubular member and a resilient plugging component 4 which seals the hollow member 1 and is penetrable by tubular members adapted as aforesaid. The tubular member 12 may be of stainless steel and the plugging component 4 may be of foamed polyethylene. <IMAGE>

Description

SPECIFICATION Accessories for optical cables The present invention relates to accessories for optical cables and has as an object the provision of such accessories in a new and improved form.

By the present invention, there is provided a terminal device for an optical cable having a fibre optic core within a protective sleeving, said device comprising a tubular member adapted to receive, surround and support and end part of the core, a hollow member for locating said tubular member in a manner such that a space which surrounds said tubular member is left between said hollow member and said tubular member and a resilient plugging component which seals the hollow member and is penetrable by tubular members adapted as aforesaid.

In a first arrangement, the tubular member terminates within the hollow member and the plugging component is positioned between the terminating end of the tubular member and an open end of the hollow member, and is constituted and arranged to move within the hollow member so that it is penetrated by the tubular member and then travels over the tubular member.

In a second arrangement, the tubular member terminates beyond the hollow member and the plugging component is located further beyond the hollow member.

A device in accordance with the first arrangement may take the form of a plug which may be fitted to the end of an optical cable. A device in accordance with the second arrangement may take the form of a socket. The socket may be constituted to be secured to the end of a further optical cable of indefinite length so that, together with a device of the first arrangement, it may be used for connecting two lengths of the cable together. Alternatively the socket may be constituted to be mounted upon equipment designed to provide or receive the optical energy, e.g. a laser, or an optical energy distributor having a plurality of outputs arranged to be fed simultaneously or otherwise with energy derived from a laser.

For best results, it is found that the tubular member is preferably formed of stainless steel.

The penetration of the plugging component removes foreign matter, particularly dust, from the end of the fibre optic core and thus contributes to the performance of apparatus using or supplying the optical energy. Contamination of the end of a core can cause difficulties, especially at such working sites as mines or quarries.

The following description of preferred embodiments of the invention, in which description reference is made to the accompanying drawing, is given in order to illustrate the invention. In the drawing: Figure 1 shows a plug in longitudinal cross-section, Figure 2 shows a socket in longitudinal crosssection, and Figure 3 is a longitudinal cross-section of the plug of Figure 1 engaged with the socket of Figure 2.

The plug of Figure 1 has a body part 1 of circular cross-section formed with a wide open-ended cavity 2 extending inwardly from end 3. Within the mouth of the cavity is a disc 4 of foamed polyethylene retained in position by an internally-projecting ridge 5.

A bore 6 extends from the opposite end 7 of the body part to communicate with cavity 2. This bore receives the end of an optical cable in the form of a core 8 of glass-fibre or other optically conductive material and a protective sheath 9. Sheath 9 has been removed from position 10 to the end 11 of the core.

Fitted within the plug is a stainless steel tube 12 which extends from a side recess 13 formed in body part 1 as far as end 11. Epoxy resin or other cementing material introduced into recess 13 secures core 8 in position. The sheathed part of the cable may be secured by an adhesive, or by crimping a narrow projecting part 1a of body part 1, if necessary with local heating.

The socket of Figure 2 has an end cap 14 formed with a cable entry 15 for an optical cable having a core 8a within a sheath 8b. Entry 15 has its entering cable secured by crimping or by an adhesive as with part la of the plug. Core 8b extends through an aperture 16 and thence through a stainless steel tube 17 to terminate, with the tube at 18.

Tube 17 is fitted at its entry end with a washertype cap 19, formed of an epoxy resin, against which bears a coil spring 20 surrounding core 8b.

Surrounding the end part of tube 17 in a slidable manner is a further tube 21, also of stainless steel, widened at both ends as shown. A housing 22 is held surrounding the tubes 17 and 21 by a flange 23 extending from end cap 14. This housing terminates in an end recess 24 in which is positioned a disc 25 of the same composition as disc 24.

When end 3 of the plug is pushed over the housing 22, disc 4 is pressed by disc 25 against the end of tube 12 and the discs are penetrated thereby.

The end of core 8 is wiped by the penetration and thereby freed from dust or other foreign matter.

After being penetrated, disc 4 is pushed by the end 27 of housing 22 into contact with the end 28 of cavity 2. Tube 12 enters tube 21 to bring the ends of cores 8 and 8b into contact or into close enough proximity to form an optical connection - see Figure 3.

The plug and socket are held in operative relationship by engagement of the ridge 5 of the plug, and internal ridges 29 and 30 of flange 23.

For simplicity of illustration, the fibre optic core is shown in the drawings as consisting of a single strand. The same principles apply to a core consisting of a bundle of strands positioned together with or without twisting. Further, the plug and socket may, when required, be provided with a plurality of the tubular and hollow members for use with cables having a plurality of optic cores.

It will be appreciated that the foregoing description of a plug and a mating socket is given by way of example only and that various departures may be made from the constructions described without departing from the ambit of the invention. For example, the plug and/or socket may be arranged for connection to hardclad fibres without removal of the cladding.

Claims

1. A terminal device for an optical cable having a fibre optic core within a protective sleeving, said device comprising a tubular member adapted to receive surround and support an end part of the core, a hollow member for locating said tubular member in a manner such that a space which surrounds said tubular member is left between said hollow member and said tubular member and a resilient plugging component which seals the hollow member and is penetrable by tubular members adapted as aforesaid.

2. A device according to claim 1 in which the tubular member terminates within the hollow member and the plugging component is positioned between the terminating end of the tubular member and an open end of the hollow member, and is constituted and arranged to be moved within the hollow member so that it is penetrated by the tubular member and then travels over the tubular member

3. A device according to claim 1 in which the tubular member terminates beyond the hollow member and the plugging component is located further beyond the hollow member.

4. A device according to any one of claims 1 to 3 in which the tubular member is formed of stainless steel.

5. A device according to any one of ciaims 1 to 4 in which the plugging component is formed of a foamed polymeric material.

6. A device according to claim 6 in which the polymeric material is polyethylene.

7. A terminal device substantially as hereinbefore described and illustrated by reference to the accompanying drawing.