WO2004008212A1

WO2004008212A1 - Optical fibre connector assembly tool

Info

Publication number: WO2004008212A1
Application number: PCT/GB2003/002673
Authority: WO
Inventors: Jan Watte; Luiz Neves Mendes; Johan Geens; Peter Eyckmans; Jan Vandenbroeck; Thomas T De Boer
Original assignee: Tyco Electronics Raychem BVBA; Tyco Electronics UK Ltd
Current assignee: Commscope Connectivity Belgium BVBA; Tyco Electronics UK Ltd
Priority date: 2002-07-16
Filing date: 2003-06-20
Publication date: 2004-01-22
Anticipated expiration: 2005-01-16

Abstract

A tool (48) for holding and manipulating at least part of an optical fibre connector, the tool comprising a shank (61) having holding means (62) at a first end thereof opposite to a second end thereof (40), by which holding means an optical fibre connector or part thereof may be held, and a sleeve (53) at least partly surrounding the shank, wherein the sleeve is retractable with respect to the shank between an extended position in which the sleeve extends along at least part of the shank at least as far as the holding means thereby to protect a connector or connector part held by the tool in use, and a retracted position in which the holding means is more exposed thereby to facilitate the attachment or removal of the connector or part thereof to, or from, the holding means.

Description

Optical Fibre Connector Assembly Tool

The present invention relates to the formation of optical fibre mechanical splices, and particularly relates to a tool and a kit for facilitating the quick and reliable assembly of an optical fibre connector.

There is a need to provide mechanical optical fibre splices which can be formed quickly and reliably by installation technicians. A problem encountered by technicians is that the need to form low-loss optical connections and to avoid the damage or stressing of the optical fibres can make the connection process difficult, time-consuming and inherently unreliable. The present invention seeks to provide a solution to this problem.

According to a first aspect, the invention provides a tool for holding and manipulating at least part of an optical fibre connector, the tool comprising a shank having holding means at a first end thereof opposite a second end thereof, by which holding means an optical fibre connector or part thereof may be held, and a sleeve at least partly surrounding the shank, wherein the sleeve is retractable with respect to the shank between an extended position in which the sleeve extends along at least part of the shank at least as far as the holding means thereby to protect a connector or connector part held by the tool in use, and a retracted position in which the holding means is more exposed thereby to facilitate the attachment or removal of the connector or part thereof to, or from, the holding means.

The invention has the advantage that because the tool includes a sleeve at least partly surrounding the shank which can extend at least as far as the holding means, an optical fibre connector (or a connector par) held and manipulated by the tool may be protected by the sleeve. Even more advantageously, however, because the sleeve is retractable, the attachment of the connector (or connector part) to the tool, or its removal from the tool, is facilitated.

Preferably, in its extended position, the sleeve extends along at least part of the shank and beyond the holding means.

Preferably, when the sleeve is in its retracted position, the holding means is exposed. Preferably the sleeve is slidable along the shank continuously between its intended and retracted positions.

Preferably the tool is arrange to facilitate a protected and reliable attachment of an optical fibre connector part held by the tool, to a connector body of an optical fibre connector.

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Accordingly, a second aspect of the invention provides a kit comprising a tool according to the first aspect of the invention, and a support for an optical fibre connector body, wherein the sleeve of the tool is arranged to fit with the support such that an optical fibre connector part held by the tool in use may be attached to a connector body held by the support, by retraction of the sleeve with respect to the shank of the tool.

Preferably the sleeve of the tool is substantially rigid. Advantageously the sleeve may be formed from metal (e.g. steel) or a plastics material, for example.

The sleeve preferably forms a sliding fit around at least part of the shank of the tool, preferably between its extended and retracted positions. More preferably, the sleeve is biased to adopt its extended position by means of a resiliently compressible component of the tool. In order to adopt its retracted position, the sleeve preferably must be urged against the resilience of the resiliently compressible component. Consequently, in its relaxed state the sleeve preferably adopts its extended position.

The resiliently compressible component preferably comprises a spring, more preferably a helical spring, advantageously located around the shank of the tool.

Preferably the tool includes a handle, and more preferably the handle is located at the second end of the shank (i.e. at the opposite end to the holding means).

The holding means of the tool may generally comprise any means suitable for holding an optical fibre connector part. Preferably, however, the holding means comprises one or more elongate holding members (preferably a plurality of elongate holding members). Preferably the elongate holding members are arranged to interlock (preferably via an axial sliding fit) with elongate members of a connector part which the tool is specifically arranged to hold and manipulate.

Accordingly, the kit according to the invention preferably includes one or more optical fibre connector parts which the tool (and more especially the holding means) is specifically arranged to hold and manipulate. Preferably, the or each connector part is a holder/ferrule assembly as described and illustrated herein.

As mentioned above, the sleeve of the tool preferably is arranged to fit with a support for an optical fibre connector body such that an optical fibre connector part held by the tool may be attached to a connector body held by the support, by retraction of the sleeve with respect to the shank of the tool. Preferably such attachment is carried out by moving the shank, and therefore the holding means, of the tool towards the connector body held by the support while the sleeve (which has been fitted to the support) remains substantially motionless relative to the connector body and the support but is retracted with respect to the shank. Consequently the connector part held by the tool is attached to the connector body held by the support in a controlled and protected manner within the sleeve of the tool.

Preferably an end of the sleeve which extends at least as far as the holding means (when the sleeve is in its extended position) is arranged to fit with the support. Preferably the fit is a mating fit. More preferably the end of the sleeve has a generally flared shape. Preferably a corresponding part of the support is generally frusto-conical in shape, such that the (female) flared end of the sleeve is arranged to form a mating fit with the (male) frusto- conical part of the support.

Advantageously the connector part held by the tool may be securely attached to the connector body held by the support by means of a bayonet-style attachment (or the like). Consequently, once the connector part has formed an initial attachment to the connector body (e.g. by simple axial insertion), the shank of the tool preferably is twisted (i.e. rotated about its axis) thereby to secure the connector part to the connector body.

Preferably the sleeve of the tool includes an open slot extending along at least part of its length from the end of the sleeve (which is preferably flared) in order to allow an optical fibre extending from a connector part held by the tool to extend out of the sleeve. Preferably the shank includes a corresponding slot for the same purpose.

Other preferred and optional features of the invention are described below and in the dependent claims.

The invention will now be described, by way of example, with reference to the accompanying drawings, of which:

Figure 1 shows a cross-sectional view of an embodiment of a ferrule of a connector according to the invention;

Figure 2 shows schematic top and side views of embodiments of ferrules of a connector according to the invention, illustrating an external profile of the ferrules intended to ensure that the ferrules may be received in a connector body of the connector in only a pre-set orientation about the axis of the ferrule;

Figure 3 shows various component parts of an embodiment of a connector body of a connector according to the invention;

Figure 4 shows the component parts of a holder/ferrule assembly according to the invention; Figure 5 shows how a holder/ferrule assembly is attached to the connector body using a tool and kit according to the invention;

Figure 6 shows two views of an assembled embodiment of a connector according to the invention;

Figure 7 shows a further view of the connector shown in Figure 4; and Figure 8 shows further views of the tool according to the invention shown in Figure

5.

Figure 1 shows an axial cross-sectional view of an embodiment of a ferrule 1 of a connector according to the invention. The ferrule, which is formed from a deformable material, preferably metal, more preferably a metal alloy, for example phosphor bronze

(preferably nickel plated to prevent corrosion) is generally cylindrical and has an axial bore 3 extending throughout its entire length. (The axis of the ferrule is indicated by the line A- A) The bore 3 has a relatively wide diameter section 3' (e.g. of 1mm diameter) for example for accommodating the buffer jacket of an optical fibre, and a relatively narrow diameter section 3" (e.g. of 0.3 mm diameter) for example for forming a snug fit around an end section of the optical fibre from which the buffer jacket has been stripped. Between the sections 3' and 3" is a frusto-conical transition section 4 of the bore. The narrow diameter section 3" of the axial bore extends from a front end 5 of the ferrule 1, and the wide diameter section 3 ' extends from a rear end 7 of the ferrule 1.

At the rear end 7 of the ferrule the circumferential external surface 8 of the ferrule includes a pair of diametrically-opposed projections 9, the purpose of which will be explained below. Towards the front end 5 of the ferrule the circumferential external surface includes a circumferential N-groove 11 which may be used, for example, in an optical fibre cleaving tool for positioning the ferrule with respect to a cleaving mechanism when the ferrule is fixed to an optical fibre extending through the ferrule.

Figure 1 does not show an important aspect of the ferrule 1, namely a part of the circumferential external surface of the ferrule which causes the ferrule to be receivable in a connector body of a connector according to the invention in only a single pre-set orientation about the axis of the ferrule. However, this feature is shown in Figure 4, and comprises a cut-away flat surface part 15 of the circumferential external surface 8 extending from the front end 5 of the ferrule. Figure 2 shows schematic top and side views of two ferrules 1 according to the invention having optical fibres 13 extending therethrough. It can be seen that both ferrules 1 (which are identical to each other) have such a cut-away flat surface part 15 of their circumferential external surface 8 which is at a fixed orientation with respect to a cleaved non-perpendicular end face 17 of the respective optical fibre 13 extending through the ferrule. This was achieved as follows.

An end section of an optical fibre 13 had its buffer jacket stripped to expose the primary coating, and the end of the fibre was threaded through the axial bore 3 of a ferrule 1 from the rear end 7 until the buffer jacket of the fibre abutted the transition section 4 of the bore. A sufficient length of the buffer jacket of the optical fibre 13 was stripped to ensure that a significant length of the stripped fibre extended from the front end 5 of the ferrule 1. The ferrule 1 (containing the fibre 13) was then inserted into a crimping and cleaving tool which is the subject of a co-pending UK patent application of the present applicant. The tool was used firstly to crimp a rear section for the ferrule 1 (i.e. a section through which the relatively wide portion 3' of the axial bore extends) around the optical fibre 13 so that the ferrule was fixed in place on the fibre. Then the tool was used to cleave a portion of the optical fibre extending from the front end 5 of the ferrule, such that a non-perpendicular end face 17 of the fibre was produced. The cut- ay flat surface part 15 of the ferrule 1 was used in the tool to orient the ferrule (about its axis) with respect to the cleaving mechanism of the tool, such that the non-perpendicular cleaved end face 17 of the fibre has a pre-set orientation with respect to the fiat surface part 15 of the ferrule 1. Because the ferrule is firmly crimped in place on the fibre, this pre-set orientation is a fixed orientation.

Figure 3 shows the various component parts of an embodiment of a connector body 19 of a connector according to the invention. The connector body 19 has a hollow, generally cylindrical shape and preferably is formed from polymer and/or metal, preferably PPS (polyphenylene sulphide) containing a glass filler. The connector body 19 has an elongate aperture 21 extending axially throughout its entire length between opposite open ends 23 and 25. Each open end 23, 25 is arranged to receive a respective ferrule 1 in a single pre-set orientation about the axis of the ferrule, with respect to the connector body.

This is achieved by each of two opposite end sections of the aperture which are intended to receive respective ferrules 1 having a cross-sectional shape corresponding to the external circumferential shape of a front portion of a ferrule 1, with a flat surface part (not shown) corresponding to the flat surface part 15 of the ferrule and arranged at a position (around the axis of the connector body 19) so as to achieve a desired orientation of its respective ferrule 1. Preferably, the two ferrules 1 received by the connector body 19 are substantially identical to each other, and therefore the flat surface parts of the aperture 21 preferably are situated on diametrically opposite sides of the aperture 1 from each other, in order to provide a relative orientation between the two ferrules as shown in the "Top view" of Figure 2. That is, the two opposing ferrules 1, when received in the aperture 21 of the connector body 19 preferably are arranged such that their front ends 5 face each other and their orientations about their axes (which are coaxial with the aperture 21) are diametrically opposed. In this way, if the non-perpendicular cleaved end faces 17 of the optical fibres (to which the ferrules 1 are fixed) have been formed in an identical way, such that their orientations relative to their respective ferrules are identical, then mere insertion of the two ferrules in the connector body 19 results in a correct opposing orientation of the two end faces 17 (as shown in Figure 2), so that an intimate contact between the two end faces over substantially their entire surfaces is possible. At a central region 27 of the connector body 19 (i.e. central along the axis of the connector body between the two open ends 23 and 25 of the aperture 21) the aperture 21 narrows at frusto-conical transition regions 29 to provide a narrow central region of the aperture 21. This narrow region of the aperture 21 is arranged to accommodate the end sections of the optical fibres 13 extending from the front ends 5 of the ferrules, and in particular is arranged to accommodate and provide support for the intimate contact between the end faces 17 of the two optical fibres. Preferably this narrow region of the aperture 21 is sufficiently narrow to prevent any significant buckling of the fibres in this region.

For formation of a fibre splice, the connector body 19 is openable to expose the narrow central region of the aperture 21 so that the end faces 17 of the optical fibres being spliced together may be observed as the ferrules 1 are inserted into the connector body (to ensure that the splicing operation is successful and the fibres are not damaged). The connector body 19 is openable in this region by means of a removable part 2 of the connector body. The connector body 19 may subsequently be permanently closed by fitting the part 2 to the main part of the connector body and sliding closure sleeves 31 over the exterior of the connector body from respective opposite ends 23, 25 of the connector body until the two sleeves 31 overlap the part 2 and are permanently retained in place between a central projection 6 on the exterior of the part 2 and respective projections 35 on the exterior of the main part of the connector body 19. The sleeves 31 slide into place along the main part of the connector body 19 with inwardly directed lips 33 sliding within a longitudinal channel 37 provided on the exterior of the connector body.

Figure 4 shows the component parts of a holder/ferrule assembly 40 according to the invention which is used to insert a ferrule 1 into the connector body 19 and to retain the ferrule in place in the connector body throughout the working lifetime of the optical fibre connector. The assembly 40 comprises a ferrule 1, a spring 41 (which performs the function of a resiliently compressible member) and a holder 39. In order to begin assembling the optical fibre connector and to form the mechanical splice, a ferrule 1 which has been fixed onto an optical fibre 13 (and the fibre subsequently cleaved as described above) is inserted into a holder 39 such that the optical fibre 13 extends completely through the holder 39, with the fibre 13 extending through the helical spring 41, and the spring 41 located between the rear end 7 of the ferrule and a rear retaining wall 44 of the holder (see figure 6). The ferrule 1 is received in the holder 39 via an open front end 45 of the holder in such a way that the pair of diametrically opposed projections 9 at the rear end 7 of the ferrule extend into respective side openings 46 of the holder 39.

The rear end 47 of the holder 39 includes a plurality of external elongate members 49 by which the holder 39, and consequently the entire assembly 40, is arranged to be held and manipulated by an assembly tool 48 according to the invention, as shown in Figure 5. Figure 5(a) shows the connector body 19 held by a support 50, which itself is arranged to be retained in a splice tray (or the like) by means of retaining lugs 52. As illustrated in Figure 5(a), one holder/ferrule assembly 40 has already been attached to one end of the connector body 19, and a second holder/ferrule assembly is to be attached to the opposite end of the connector body such that the ferrule 1 is received in the connector body.

Views (a) and (b) of Figure 5 illustrate the process of attachment of the second holder/ferrule assembly to the connector body by means of the assembly tool 48. The tool 48 comprises a handle 51 from which a central elongate shank and a surrounding protective elongate sleeve 53 extend. The end of the central shank of the tool 48 (not shown in detail) opposite to the end attached to the handle 51 has elongate holding members which are arranged to interlock (via an axial sliding fit) with the elongate members 48 of the holder 39 of the assembly 40, so that the assembly 40 may be held and manipulated by means of the tool. The elongate protective sleeve 53 has an open slot 54 extending along at least part of its length from a flared open end 55 of the sleeve, in order to allow the optical fibre 13 extending from the rear end 47 of the holder 39 to extend out of the sleeve 53, as shown in views (b) and (c) of Figure 5. The protective sleeve 53 is retractable with respect to the central shank of the tool, in a direction towards the handle 51. Between the handle 51 and the sleeve 53 is a helical spring 56 which, in its relaxed state, causes the sleeve to adopt an extended position away from the handle 51 such that it surrounds and extends beyond the ferrule/holder assembly 40 held by the shank of the tool. In particular, the tool is arranged such that when the sleeve 53 is in its fully extended position the sleeve extends beyond, and therefore protects, the exposed cleaved optical fibre 13 extending from the front end 5 of the ferrule 1 of the assembly 40. In this way, the cleaved optical fibre end section is protected from damage during manipulation of the assembly prior to its insertion in the connector body 19. The flared (female) open end 55 of the protective sleeve 53 of the tool 48 is arranged to form a mating fit with a corresponding (male) frusto-conical part 57 of the support 50, the part 57 partially surrounding an open end of the connector body 19 located on the support.

This mating fit is illustrated in view (b) of Figure 5. View (c) shows the subsequent operation whereby the handle 51 of the tool 48 is pushed forwards towards the connector body 19 as indicated by arrow A. This motion of the handle causes the central shank of the ool, and hence the ferrule/holder assembly 40 held by the shank, to move towards the

\ connector body 19 within the protective sleeve 53. The protective sleeve 53 of the tool remains motionless relative to the connector body 19 and the support 50, but it is retracted (by compression of the helical spring 56) relative to the shank and the handle 51 of the tool, as indicated by arrow B. Consequently the ferrule 1 and the cleaved end 17 of the optical fibre 13 to which the ferrule is fixed are inserted in a controlled and protected manner into the connector body 19.

As described above, each holder 39 includes a resiliently compressible member (as shown, a spring 41) situated between the respective ferrule 1, and the rear retaining wall of the holder. When a ferrule 1 is inserted into the connector body 19, its holder 39 is pushed onto the connector body initially without twisting the holder 39 relative to the connector body. The first of the two ferrule/holder assemblies 40 to be pushed onto the connector body 19 (i.e. the assembly 40 already attached to the connector body, as shown in Figure 5) is immediately secured to the connector body 19 by twisting the tool 48 (and hence the holder 39 of the assembly 40) with respect to the connector body 19 so that slots 43 of the holder 39 interlock with lugs 42 in a bayonet-style attachment. When the holder 39 is twisted with respect to he connector body 19 it is also twisted with respect to the ferrule 1 which it holds, because the ferrule has been inserted into the connector body and is unable to rotate due to its keyed orientation in the connector body (i.e. due to the corresponding flat surface parts of the ferrule 1 and the connector body 19). This twisting motion of the holder 39 with respect to its ferrule 1 causes the projections 9 at the rear end of the ferrule to dig into the material of the holder 39 (which preferably is formed from a plastics material, more preferably PBT, i.e. polybutylene teraphthalate) so that the ferrule is locked in position axially with respect to the holder.

Because the length of cleaved optical fibre 13 extending beyond the front end 5 of its respective ferrule 1 will vary slightly from fibre to fibre (due to cleavage tolerances) the distances by which the ferrules must extend into the connector body in order to form a non- stressed splice between contacting cleaved end faces of the optical fibres will vary from splice to splice. Consequently, when the second of the two ferrule/holder assemblies is attached to the connector body (i.e. after the first ferrule/holder assembly has already been secured to the connector body by a bayonet -style attachment), before the second assembly is twisted with respect to the connector body to secure the bayonet attachment, the resiliently compressible spring member 41 of the assembly will accommodate any so-called "fibre repel" between the fibres to be spliced. Fibre repel may occur due to cleavage tolerances, and results from the combined length of exposed fibre between the two ferrules being too great. This is accommodated by the resiliently compressible spring member 41 of the second assembly 40 compressing to allow the ferrule 1 of the second assembly to move rearwardly away from the opposite ferrule, so that a good splicing contact between the two optical fibres may be achieved. The resilience of the spring member 41 ensures, however, that there is a good contact between the cleaved end faces of the fibres.

Once a good splicing contact between the fibres, without significant buckling of the fibres, has been achieved, the second holder is twisted relative to the connector body 19 to secure a bayonet-style attachment between the holder and the connector body by means of slots 43 and lugs 42. The connector body is then closed by means of the part 2 and the closure sleeves 31 as described above, and the splicing of the fibres is complete.

Figure 6 shows cross-sectional and exterior plan views of the connector body 19 of Figures 3 and 5 with two ferrules 1 received therein, but with the central region 27 still exposed. Each ferrule 1 is retained in place within the connector body 19 by means of a respective holder 39 that is attached to the respective open end 23,25 of the connector body behind the ferrule 1. As described above, each holder 39 is attached to the connector body 19 by means of a bayonet-style attachment, with lugs 42 on the connector body 19 received in corresponding slots 43 of the holder. A completed, fully closed, connector according to the invention is illustrated in Figure 7.

Figure 8(a) shows in detail the main components of the assembly tool 48 according to the invention, namely the handle 51, shank 61, helical spring 56 and sleeve 53. The shank 61 is arranged to be secured to the handle 51 by connection tabs 66 at the second end of the shank. At the opposite, first end of the shank 61 are shown the elongate holding members 62 by which the tool holds the assembly 40. The shank 61 also includes an open slot 64 which, together with the slot 54 of the sleeve allows an optical fibre extending from the rear end of an assembly 40 held by the tool, to extend out of the tool. Views (b) and (c) of Figure 8 show the assembled tool with the sleeve fully retracted, thereby exposing the holding members 62. In view (c) and assembly 40 is held by the tool.

As shown in figures 5 and 8, the resiliently compressible component (i.e. spring 56) and/or the sleeve 53 are retracted at least partly within the handle 51 when the sleeve is in its retracted position.

Claims

1. A tool for holding and manipulating at least part of an optical fibre connector, the tool comprising a shank having holding means at a first end thereof opposite to a second end thereof, by which holding means an optical fibre connector or part thereof may be held, and a sleeve at least partly surrounding the shank, wherein the sleeve is retractable with respect to the shank between an extended position in which the sleeve extends along at least part of the shank at least as far as the holding means thereby to protect a connector or connector part held by the tool in use, and a retracted position in which the holding means is more exposed thereby to facilitate the attachment or removal of the connector or part thereof to, or from, the holding means.

2. A tool according to claim 1, in which, in its extended position the sleeve extends along at least part of the shank and beyond the holding means.

3. A tool according to claim 1 or claim 2, in which, when the sleeve is in its retracted position, the holding means is exposed.

4. A tool according to any preceding claim, in which the sleeve is slidable along the shank continuously between its extended and retracted positions.

5. A tool according to any preceding claim, which is arranged to attach an optical fibre connector part held, in use, by the holding means of the tool, to a connector body of an optical fibre connector.

6. A kit comprising a tool according to any preceding claim and a support for an optical fibre connector body, wherein the sleeve of the tool is arranged to fit with the support such that an optical fibre connector part held by the tool in use may be attached to a connector body held by the support, by retraction of the sleeve with respect to the shank of the tool.

7. A tool or kit according to any preceding claim, in which the sleeve is substantially rigid.

8. A tool or kit according to any preceding claim, in which the sleeve forms a sliding fit around at least part of the shank of the tool between its extended and retracted positions.

9. A tool or kit according to any preceding claim, in which the sleeve is biased to adopt its extended position by means of a resiliently compressible component of the tool.

10. A tool or kit according to claim 9, in which, in order to adopt its retracted position, the sleeve must be urged against the resilience of the resiliently compressible component of the tool.

11. A tool or kit according to claim 9 or claim 10, in which, in a relaxed state the sleeve adopts its extended position.

12. A tool or kit according to any one of claims 9 to 11, in which the resiliently compressible component comprises a spring.

13. A tool or kit according to claim 12, in which the spring comprises a helical spring located around the shank of the tool.

14. A tool or kit according to any preceding claim, in which the tool includes a handle located at the second end of the shank.

15. A tool or kit according to any preceding claim in which the holding means of the tool comprises one or more elongate holding members.

16. A kit according to claim 6 or any claim dependent thereon, the kit further comprising one or more optical fibre connector parts which the tool is specifically arranged to hold and manipulate.

17. A kit according to claim 6 or any claim dependent thereon, in which the attachment of a connector part held by the tool, to a connector body held by the support, is arranged to be carried out by fitting the sleeve of the tool to the support, and moving the shank of the tool towards the connector body while the sleeve remains substantially motionless relative to the connector body and the support but is retracted with respect to the shank.

18. A kit according to claim 6 or any claim dependent thereon, in which an end of the sleeve of the tool which extends at least as far as the holding means when the sleeve is in its extended position, is arranged to fit with the support.

19. A kit according to claim 18, in which said end of the sleeve is generally flared and the fit with the support is a mating fit.

20. A kit according to claim 16 or any claim dependent thereon, further comprising at least one said optical fibre connector body, and in which the (or each) optical fibre connector part is arranged to be securely attached to a said connector body by means of a bayonet-style attachment.

21. A kit according to claim 20, in which once a connector part has formed an initial attachment to a connector body with the connector part still held by the tool, the shank of the tool may be twisted with respect to the connector body to form the secure bayonet-style attachment of the connector part to the connector body.

22. A tool or kit according to any preceding claim, in which the sleeve of the tool includes an open slot extending along at least part of its length arranged to allow an optical fibre extending from a connector part held by the tool in use to extend out of the sleeve.

23. A tool or kit substantially as hereinbefore described and/or as illustrated in the accompanying figures 5 and /or 8.