FR2520515A1 - DEVICE FOR CONNECTING TWO OPTICAL FIBER SHEATHING ASSEMBLIES AND MEANS FOR SUPPORTING AND FITTING FIBERS INCLUDED IN THE DEVICE - Google Patents

Abstract

THE INVENTION CONCERNS THE CONNECTION OF TWO COVERS 1 OF OPTICAL FIBERS 2 IN WHICH THE FIBERS ARE DISTRIBUTED AROUND A CYLINDER OR A TABLECLOTH. THE CONNECTION DEVICE INCLUDES A BOX 5 WHICH IS SOLIDARITY WITH THE SHELLS OF THE ASSEMBLIES AND WHICH IS EMPLOYED WITH A MATERIAL M, SUCH AS AN ELASTOMERIC GEL, FULLY COATING THE SUPPORT AND ENDING MEANS 3 OF THE ENDS OF THE FIBERS TWO TO TWO . EXTERNAL STRESSES APPLIED TO THE BOX AND ASSEMBLIES ARE ABSORBED BY THE GEL AND DO NOT DISTURB THE BONDS OF THE OPTICAL FIBERS. THE SUPPORT MEANS INCLUDE TWO SLOTTED HALF-SUPPORTS 3A, 3B, ALIGNMENT CYLINDERS 33 OF THE HALF-SUPPORTS AND MEANS, SUCH AS A FLEXIBLE PLATE IN U 36, TO PUSH ONE AGAINST THE OTHER HALF-SUPPORTS SUPPORTS AND JOINT FIBERS. A SECOND BOX MAY BE PROVIDED TO PROTECT THE FIRST BOX 5 AND IN PARTICULAR SEVERAL FIRST BOXES WHEN THE TWO SETS ARE COMPOSITE CABLES OR TABLECLOTHS CONTAINING EACH OF THE ELEMENTARY SUB-CABLES OR SUB-CABLES.

Description

DEVICE FOR CONNECTING TWO SHEATHED OPTICAL FIBER ASSEMBLIES
AND MEANS FOR SUPPORTING AND FILLING UP FIBERS INCLUDED IN THE DEVICE
The present invention relates generally to the connection of two sets of optical fiber sheaths such as cylindrical cables in which the fibers are distributed circularly, or such as ribbons or plies in which the fibers are coplanar.

The means for supporting and abutting the fibers two by two of the two assemblies may comprise a flat support having a large grooved face or a cylindrical support having peripheral longitudinal grooves, each groove containing two abutted fibers.

In known connection devices, the support forming the splice of the fibers of the two assemblies is protected against any external attack by first protective means. These protective means generally consist of assembling a large number of parts, some of which external constitute a housing surrounding the splice and secured, for example by wrapping, sheaths of the assemblies and of which other internal ones extend the splice and are attached to the bearing elements of the assemblies in order to stiffen the assembly. These internal parts are in direct mechanical contact on the one hand with the support of the ends of the fibers and on the other hand with the load-bearing elements of the two assemblies. Although elastic joints are sometimes introduced between two internal parts, none remains not less than external mechanical stresses, such as pulls, shear vibrations and bending, applied to the assemblies during their installation or repair on site in particular, are transmitted to the support of the optical fibers. The support generally being the assembly of two half-supports grooved, the stresses received then cause misalignment of the axes of the ends of the fibers at the junction of the half-supports which are one of the essential causes of the attenuation of the optical signals conveyed in the fibers
The main object of the present invention is therefore to completely isolate the splice, or support and abutment means, of the fibers of two assemblies with respect to the protection means, or shoemaker, surrounding the splice and also with respect to the means carrying the fibers in the two sets.

 To this end, a device for connecting two sets sheathed with optical fibers comprising means for supporting and abutting the ends of fibers two by two of the two sets and first protection means which surround said support and abutment means and of which the ends are integral with the sheaths of the two assemblies, is characterized in that the support and abutment means are embedded in a coating material inside the first protection means. The coating material is for example a slowly polymerizing elastomer gel, which completely fills the interior of the first protective means and which is poured for example by means of a syringe inserted into an appropriate hole of the first protective means. of fibers between the support means and the sheathed ends of the assemblies being loose before introduction of the elastomeric gel, the mechanical stresses transmitted by the assemblies or by the protective means are thus absorbed by the elastomeric gel. No part included in the support and abutment means is in direct contact with the internal walls of the first protection means as well as with the sheaths and load-bearing elements of the assemblies.

 Second protection means which surround the first protection means and the ends of which are integral with the sheaths of the two assemblies can be provided for protection against any external attack, such as shock or humidity. The rigidity of the connection of these second protective means to the sheaths of the sets of optical fibers can be obtained by means, such as two rings with female cone, which enclose and deform a flexible biconical male ring and crushes it against the sheath of the respective set.

 The invention also applies to the connection of two composite assemblies sheathed with optical fibers such as two cylindrical cables containing a plurality of cylindrical supporting sub-cables or such as two ribbons formed by the wrapping of superimposed sub-ribbons of coplanar fibers.

 According to the invention, when the support and abutment means comprise two identical elongated half-supports, parallelepipedic or cylindrical, hollowed out with first longitudinal grooves in which the ends of the optical fibers abutted two by two of the two sets as well as two second longitudinal grooves, two cylinders, and flexible fasteners pressing the two cylinders in the second grooves to align the first grooves, it is necessary to provide means making integral the half-supports which must be fixed to them, and therefore completely isolating the assembly of this splice from the connection device housing and from the sheathed ends of the assemblies. The main function of these means is to push the transverse edges of the half-supports against each other at the ends of the fibers view to end these two by two. They may include a longitudinal piece having two bent ends which are applied by their own opposite flexions against the transverse edges remote from the half-supports.

Other advantages of the invention will appear more clearly on reading the following description of several preferred embodiments with reference to the corresponding appended drawings, in which
- Fig. 1 is a perspective view of the stripped end of a known fiber optic cable provided with a grooved rod
- Fig. 2 is a perspective view of the stripped end of a known optical fiber cable provided with tubes each containing an optical fiber, distributed around the cable rod
- Fig. 3 is a longitudinal side view partially in section of the means for supporting and abutting the ends of two sets of optical fibers, provided with two half-supports;
- Fig. 4 is a sectional view along the line IV-IV of FIG. 3, corresponding to the junction plane of the half-supports; ;
- Fig. 5 is a top view of the support and abutment means of FIG. 3
- Fig. 6 is a sectional view on a large scale of a v-groove of a half-support receiving a fiber or an alignment cylinder
- Fig. 7 is a sectional view on a large scale of an edge groove of a half-support receiving a fiber or an alignment cylinder
- Fig. 8 is an exploded view of first means of protection of a connection device containing a splice according to FIGS.

3 to 5;
- Fig. 9 is a sectional view along line IX-IX of the
Fig. 8, after closing of the housing of the first protection means;
- Fig. 10 is a longitudinal view partially in section of other first protective means containing a splice according to FIGS. 3 to 5;
- Fig. it is a sectional view along line XI-XI of the
Fig. 10
- Fig. 12 is a longitudinal half-section of second protection means which may contain first protection means according to FIG. 8 or 10;
- Fig. 13 is a schematic sectional view of a composite cable comprising several supporting sub-cables such as that shown in the
Fig. 1 or 2 ; and
- Fig. 14 is a schematic longitudinal view partially in section of second means for protecting the splices of the pairs of sub-cables of two composite cables.

 For a better understanding of the invention, reference is made hereinafter, by way of nonlimiting example, to the connection of two sets of optical fibers such as two cylindrical cables. In a cylindrical cable, the optical fibers are initially distributed at the periphery of a rod with axial symmetry and are to be applied on a flat grooved support in view of their abutting two by two with the fibers of the other cable.

 Figs. 1 and 2 briefly recall two cylindrical structures of known fiber optic cables, although others may be used.

 According to FIG. 1, the cable 1 is composed of a structure with axial symmetry, such as a cylindrical rod 10, and a peripheral sheath 11, generally composite, the outer envelope of which is constituted by a wrapping. The rod 10 is for example made of plastic. It contains in its center a carrier element 12, generally rigid, which may consist of a steel wire or of several stranded steel wires, or alternatively of several non-metallic elements such as glass fibers. The periphery of the rod 10 is hollowed out with axial parallel grooves 13, or general grooves, here ten in number, which are equally distributed and which each contain an optical fiber 2.

 The lc cable according to Fig. 2 also comprises a cylindrical rod 10c in which is coated a carrier element 12c, such as a generally flexible steel wire, and a peripheral island sheath. Inside the island sheath, the cable la comprises tubes 13c, here six in number, which are equally distributed and twisted around the rod 10c. Each tube 13c contains an optical fiber 2c.

 Referring to Figs. 3 to 5, we describe the splicing of the ends of the optical fibers 2a, 2b of two sets such as sheets 1a and 1b on a flat support which come directly from two ribbons of known co-planar optical fibers or else indirectly from two structures a axial symmetry, such as two cylindrical cables 1 (Fig. 1) or the (Fig. 2), by means of a sheet preparation device in accordance with French patent application 81-20171 filed on October 27, 1981 or with patent application filed today on behalf of the current applicants.

 The essential component of the splice or support and abutment means consists of two parallelepipedal half-supports 3a and 3b. These two half-supports are identical and come from the same flat support which has been sawn or broken according to a breaking point corresponding to the transverse edge edges 30 of the half-supports 3a, 3b.

 One of the large faces of each half-support 3a, 3b is hollowed out with first grooves 31a, 31b which are longitudinal, parallel and equidistant. Each groove 31a, 31b is suitable for receiving an optical fiber 2a, 2b from the respective sheet 1a, 1b.

 In each of the large longitudinal sides of the half-supports 3a, 3b is provided a wide groove 32a, 32b which is intended to receive half of an alignment cylinder 33. When the two alignment cylinders 33 are each applied to the bottom two grooves 31a and 31b, they align two by two the first grooves 31a and 31b in order to join the ends of the fibers 2a and 2b that they contain. This alignment is carried out after fixing in particular by bonding the fibers in the small grooves and simultaneous rectification of their ends and the edges 30 by means of a plane front rectification machine as described in French patent application 81-23721 filed on 18 December 1981.

 As shown in Fig. 6, the grooves 30 and 31 may have a vee or blunt vee profile, flat or convex aoetes. The dimensions of the profile of the grooves 30 and 31 are such that the fibers 2 and the cylinders 33 respectively exceed the large grooved face and the longitudinal sides of the half-supports 3a, 3b. The grooves are made in the initial support 3 before separation into the two half-supports 3a, 3b by any suitable known means such as molding, machining or chemical etching.

 Preferably, the support 3 is made of thermoplastic or thermosetting material, or of chemical polymerization. It is obtained by molding.

In practice, it has been found that the grooves 31 and 32 do not need to have a very precise profile, but only two parallel rectilinear edges A1, A2 on the sides of the groove, as shown in FIG. 7. This type of profile is obtained for example by means of three passes P1 to P3 of a tool with a convex working end in the support 3, before separation into two half-supports 3a, 3b. First two passes
P1 and P2 overlap substantially in the middle of the groove to be formed and provide a groove which has a width greater than the diameter of the fiber or of the alignment cylinder and a depth substantially equal to one third of this diameter. A third pass P3 at double depth and in the middle of the groove then forms two parallel edges A1 and
A2 having very good qualities whatever the geometric errors of the tool used. The edges A1 and A2 are at mid-depth in the groove 31 or 32. The fiber 2 or the cylinder 33 will come to rest precisely on the two edges A1 and A2.

 According to another embodiment, the small grooves 31a, 31b are separated by longitudinal partitions 34a, 34b which protrude above and in the middle of the large grooved faces of the half-supports, over part of the length of the half-supports, as shown in Figs. 4 and 5. These partitions can also be obtained by molding or machining.

They contribute to the establishment and positioning of the fibers while possibly leaving room for the application of preseurs which hold the fibers during their bonding in the grooves 31a, 31b.

 The two alignment cylinders 33 are applied in the grooves 32a and 32b of the half-supports by elastic means such as two flexible transverse fasteners or clips 35a, 35b. The fastener 35a, 35b of each half-support 3a, 3b is U-shaped and has two vertical parallel sides 350, preferably bent in S, which enclose the opposite peripheries of the two cylinders 33, and a flat 351 which connects the two sides 351 and which is underlying the large non-grooved face of the respective half-support. This assembly is rigorously free of play and extremely precise, taking into account the quality of the surfaces.

 After rectification of the optical fibers on the joining edges 30, means are introduced to push the half-supports 3a and 3b against each other in order to reconstitute the initial support 3. The pushing means consist of a longitudinal attachment 36 symmetrical with respect to the junction plane 30. The fastener 36 comprises a flat 360 which is underlying the flat 351 of the two fasteners 35a, 35b, and two U-folded sides 361a, 361b which extend the flat 360 longitudinally. The ends hoses of the outer bent branches 362a, 362b on the sides 361a, 361b are separated and then released to be applied by their own flexions against the distant transverse edges 37a, 37b of the half-supports 3a, 3b by means of appropriate tools. antagonists exerted by the branches 362a and 362b can be increased by the addition of a plate 38 underlying the plate 360. The plate 38 comprises two transverse slots 380a and 380b into which are introduced its the lower vertices of the U-shaped sides 361a and 361b and against the distant transverse walls from which the elbows of the distant and arched branches 362a and 362b bear so as to determine shorter lever arms.

 The symmetrical positions of the cylinders 33 relative to the longitudinal axis of the half-supports 3a, 3b and the action of the elastic means such as the transverse fasteners 35a and 35b on the one hand, and the longitudinal fastener 36 on the other hand along two axes passing through the center of gravity of the half-supports 3a, 3b, that is to say the center of gravity of the junction plane 30, achieve equilibrium conditions favorable to the conservation of the shapes and therefore to the quality of the fiber connection over time.

 The support and abutment means such as - described with reference to Figs. 3 to 5 are completely independent of the protection means which enclose and protect them, as well as the ends of the cables carrying optical fibers. The protection means include a boot which protects the connection of the fibers against any external stresses. Indeed, especially on site, a cable can be subjected to stresses, pulls or vibrations of all kinds. To protect the junction 30 of the fibers against these stresses, as well as against any introduction of water or moisture, the invention provides for completely coating the splice comprising the half-supports 3a, 3b, with an "elastic" material. M which is cast in the housing and which acts as a shock and vibration absorber. The material M can be an elastomer gel of very low hardness, polymerizing slowly. A quantity of the material M is poured into the bottom of the housing, then after fitting the splice, an injection of the material M allows the housing to be completely filled.

 A.Title of nonlimiting example will be described below two embodiments of first means of protection of the connection device including a splice as shown in Figs. 3 to 5, for cables having an axially symmetrical structure, generally cylindrical, although the two sets of optical fibers may be two strips of coplanar optical fibers. In the latter case, it will suffice to replace the cylindrical parts of the housing, parts with rectangular sections at least as regards those near the stripped ends of the cables.

 A first embodiment is shown in FIG. 8. The first protection means 5 comprise a lower half-casing 5i, an upper half-casing 5s and two crimp rings 50a and 50b. The half-housings 5i, 5s are practically identical and symmetrical with respect to the longitudinal axis of the half-supports 3a, 3b. Each half-housing is composed of a hollow central elongated half-cylinder 51i, 51s whose length is at least as great as the distance separating the ends 14a, 14b of the sheaths of the cables la, lb to be connected and whose diameter is greater the overall width of the entire splice 3a - 3b. The ends of each half-cylinder 51i, 51s are terminated by two substantially semi-cylindrical end pieces 52a, 52b via frustoconical transitions. The inside diameter of the end pieces 52a, 52b is equal to or substantially less than the outside diameter of the cables la , lb. The outside diameter of the end pieces 52a, 52b is substantially smaller than the inside diameter of the rings 50a, 50b before crimping.

The closure of the housing 5 takes place in the following manner
The two rings 50a and 50b are threaded respectively on the sheaths of cables 1a, 1b before any stripping operation of the cables and development of the fibers.

The two sheathed and carrying ends of the fibers 14a and 14b are kept in alignment by means of a tool - not shown and not belonging to the object of the invention - which frees the fibers of any axial force. This tool is used in particular during the semi-automatic assembly forming the splice as shown in the
Fig. 5. On this subject, it will be noted that prior to the formation of the splice by assembling the half-supports 3a, 3b and bonding the fibers 2a, 2b in the grooves 31a, 31b, the fibers which are distributed circularly in the cables have their ends which are equally distributed coplanarly by means of the sheet preparation device described in the aforementioned patent application 81-20171 or in the patent application filed today in the name of the current applicants. With reference to the last patent application, the piece called distributor R transforming the cylindrical distribution in the cable into a coplanar distribution of the fibers is fixed to the cut end, forming a journal, of the carrier element 12a, 12b of each cable la, lb. The other end of the distributor is in front of an edge 37 of a half-support without being in contact with it. The locations of the two distributors are indicated by the braces Ra and Rb in Fig. 8. Of course, when the cables are ribbons of coplanar fibers, such web preparation devices are not used.

 The lower half-casing 5i is filled approximately two-thirds full with elastomer gel M and is placed under the splice 3a - 3b so that no element of the splice, such as the longitudinal attachment 36 or the plate 38 (Fig. 3) come directly into contact with the internal wall of the half-housing 5i. The edges of the upper half-casing 5s fit into those of the lower half-casing 5i and are made integral by sliding the rings 50a and 50b respectively on the pairs of end pieces 52a and 52b. Then the rings are crimped by forming diametrically opposite beads 53 as shown in detail in FIG. 9.Two adhesive tapes - not shown - are placed overlapping on the contiguous edges of the half-housings 5i and 5s in order to achieve a sufficient seal during the introduction of the elastomer gel M. Celuici is introduced through one of two holes upper 54 which are formed in the half-cylinder 51s, by means of a syringe. The filling of the boot with the elastomer gel is finished when the gel comes out through the other hole 54.

 The crimping of the rings 50a and 50b is sufficient to ensure mechanical rigidity of the connection device for cables such as that shown in FIG. 1, which comprises a carrier element 12 having a relatively high rigidity.

 When the carrier element is flexible, such as that 12c of the cable shown in FIG. 2, the invention provides for the use of a second embodiment shown in FIG. 10. In this case, the first protection means 6 also comprise two half-housings which are hollow and nestable half-cylinders 6s and 6i, two larger crimping rings 60a and 60b which here have an internal diameter substantially equal to the diameter outer half-housings, and two pairs of half-rings 61a and 61b which are snap-fit around the ends of the sheaths of the cables la and lb respectively.

 The half-rings 61a, 61b have an external diameter which is equal to the internal diameter of the half-housings 6s, 6i and an internal diameter which is substantially less than the external diameter of the cables la, lb so that their assembly ensures a first tightening and a slight deformation of the tubes 13c (Fig. 2) each containing an optical fiber. In each lower half-ring of a pair 61a, 61b is made a longitudinal groove 62a, 62b or an axially offset hole, in which is engaged the cut end 120a, 120b of the flexible support element 12a, 12b, generally metallic, of the respective cable la, lb after passage between the fibers la, lb and folding, as shown in Figs. 10 and 11. After these operations, the half-casings 6s and 6i are filled with elastomer gel, as for the first embodiment shown in FIG. 9, and are made integral by threading the outer rings 60a and 60b and crimping them.

 The carrier elements 12 of the fibers which mainly have the function of supporting all the axial forces applied to the cables, are thus trapped between the half-housings 6s, 6i and the half-rings 61a, 61b in the connection device. This imprisonment guarantees good resistance of the connection device, especially in traction.

 The first protective means as described with reference to Figs. 8 and 9 or in Figs. 10 and 11, can then be enclosed in second means of protection against any external attack.

 When the cables to be connected each comprise only one support element such as 10-12 or 10c-12c, the second protection means are preferably those shown in FIG. 12. All the elements constituting the second protection means are cylindrical and have been threaded beforehand at the ends of the respective cables la, lb before any stripping and splicing operation.

 According to FIG. 12, the second protection means 7 comprise a sheath 70 which surrounds the entire housing 5 as illustrated, or 6 and of which each end 701a, 701b is threaded in front of a collar 702a, 702b. The assemblies at the ends of the sheath being identical, only that relating to the cable shown on the left in FIG. 12 will be described.

 A ring 711a formed of half-rings with male cone converging towards the cable la has an internal diameter substantially equal to the external diameter of the sheath of the cable la. It slides along the sheath until it stops against the end 701a of the sheath 70 under the thrust exerted by a ring with a complementary female cone 712a, when a nut 713a is screwed around the threaded end 701a. The nut 713a has a recess which contains the female cone ring 712a. The tightness of the nut assembly 713a sleeve 70 is obtained by means of two elastomer O-rings 721a which are separated by means of thin rings 9 722a and which are compressed by the end of the nut. 713a against the collar 702a.

 The mooring of the cable sheath la is obtained by means of a relatively flexible male biconical ring 730a, the internal ends of which are separated by a curvilinear recess 731a and are only carried by the sheath. This ring 730a is trapped between a female cone ring 732a which abuts against the rear of the nut 713a, and another female cone ring 733a. The rings 733a, 730a and 732a surrounding the cable sheath la are housed in the front bore of a socket 740a, which is contained in a second nut 74a, the rear end of which is flush with the sheath of the cable la. threaded of the nut 74a is screwed around the threaded rear end of the first nut 713a in order to deform the biconical ring 730a and crush it on the sheath and therefore to anchor the assembly to this sheath under the opposing thrusts of the rings with cone. female 733a and 733a. In this latter assembly, the sealing is carried out by one or more elastomer O-rings 741a which are contained in the sleeve 740a and which are pressed against the rear of the female cone ring 733a when the nut 74a is screwed.

 However, the two connection cables can be composite cables 8a, 8b which include sub-cables such as 1, each having a single supporting element 12. FIG. 13 shows for example a composite cylindrical cable 8 which comprises six supporting sub-cables which are distributed around a central carrying cable and which are surrounded by a composite sheath 80 generally with several concentric envelopes having different thicknesses and compositions. The first means for protecting the splice of each pair of corresponding sub-cables la, lb in the two composite cables 8a, 8b to be connected are carried out according to FIGS. 8 and 9 or Figs. 10 and 11 and are enclosed in a box 5 or 6. The boxes -of which only one is shown in FIG. 14 are then enclosed in a sealed box 9 and can be embedded in an elastomer gel 90 poured into the box 9 or preferably can each be enclosed in one of the fasteners of the circlip type or pliers 91 of a central bar 92 internal to the box 9. The box 9 constituting the second common protection means for the first protection means for the pairs of cables la, lb can be similar to the means 7 shown in FIG. 12. The ends 91a, 91b of the box 9 are therefore moored respectively to the sheaths 80 of the composite cables 8a and 8b.

 As already said, fall within the scope of the invention second protective means such as 9 for splicing a plurality of pairs of coplanar sub-ribbons of optical fibers which are superimposed in the sheaths of two composite ribbons.

 The means for supporting and abutting the fibers, such as parallelepipedic 3a and 3b, can be two identical cylindrical half-supports in which are formed diametrically opposite longitudinal grooves, such as 32, to receive two alignment cylinders and a plurality of small longitudinal grooves, such as 31, equally spaced on either side of the alignment grooves, such as 32, for receiving the ends of the optical fibers of the cables to be connected.

Claims (20)

Resell i cat ions  1 - Device for connecting two sheathed sets (1) of optical fibers (2) comprising means (3) for supporting and abutting the ends of the fibers two by two of the two sets and first protection means (5; 6) which surround said support and abutment means (3) and the ends of which are integral with the sheaths (11) of the two assemblies (1), characterized in that the support and abutment means (3) are embedded in a material coating (M) inside the first protection means (5; 6).  2 - Device according to claim 1, characterized in that the coating material (M) is an elastomer gel poured inside the first protective means (5; 6).  3 - Device according to claim 1 or 2, characterized in that the first protection means (5) comprise two half-boots (5i, 5s) nestable along the support and abutment means (3) and the containers embedded in said coating material (M) and two rings (50a, 50b) which are crimped around the ends (52a, 52b) of the half-housings (Si, 5s) surrounding the sheaths (11) of the two assemblies (la, lb) .  4 - Device according to claim 1 or 2 for two sets of optical fibers (1, Fig. 10) each including flexible carrier means (12c, Fig. 2), characterized in that the first protection means (6) comprise two half-housings (6i, 6s) nestable along the support and abutment means (3) and containing them embedded in said coating material (M), two small rings (61a, 61b) surrounding the sheaths (11 ) of the two assemblies (la, lb) and having housings (62a, 62b) for receiving the folded ends (120a, 120b) of the carrier means, and two large rings (60a, 60b) which are crimped around the ends of the half housings (6i, 6s) surrounding the small rings (61a, 61b).  5 - Device according to one of claims 1 to 4, characterized in that it comprises second protection means (7) which surround the first protection means (5; 6) and the ends of which are integral with the sheaths ( 11) of the two assemblies (1).  6 - Device according to claim 5, characterized in that the second protection means (7) comprise at each end a flexible ring (730a) surrounding the sheath (11) of the respective assembly (la) and means (732a , 733a) to deform the flexible ring (730a) and crush it against the sheath.  7 - Device according to claim 6, characterized in that the flexible ring (730a) has a recess (731a).  8 - Device according to claim 6 or 7, characterized in that the flexible ring (730a) is male biconical and in that the deformation means comprise two rings cone.femel; te (t32a, -7.33å) stem- casing on the male cone ends of the biconical ring (730a) and a nut (74a) - screw (713a) assembly surrounding the sheath (11) and the rings (730a, 732a, 733a) to exert antagonistic thrusts on the rings with female cone (732a, 733b).  9 - Device according to claim 8, characterized in that the nut (74a) contains elastic O-rings (741a) surrounding the sheath (11) of the respective assembly (la).  10 - Device according to one of claims 5 to 9, characterized in that the second protection means (7) comprise a sheath (70) surrounding the first protection means (5; 6) and at each end of the sheath a nut (713a) screwed onto the end (701a) of the sleeve and an assembly of two rings with male cone (71 la) and female cone (712a) contained in said nut (713a) and pushed by the latter against the end (701a) of the sheath (70).  11 - Device according to claim 10, characterized in that the second protection means comprise elastic O-rings (721a) pressed by the end of the nut (713a) against a collar (702a) of the sleeve (70).  12 - Device according to one of claims 1 to 4, wherein the two sheathed sets of optical fibers (la, lb) are two sub-assemblies included respectively in two composite assemblies (8a, 8b) including the sheaths (80) contain a plurality of sub-assemblies, characterized in that it comprises second protective means (9) in which the first protective means - (5; 6) of each pair of sub-assemblies are contained, and which have their end (91a, la, 91b) of the sheaths (80) of the two composite assemblies (8a, 8b).  13 - Device according to claim 12, characterized in that the first protection means (5; 6) are embedded in a coating material (90) filling the second protection means (9).  14 - Device according to claim 12 or 13, characterized in that the first protection means (5; 6) are embedded in flexible clips (91) fixed inside the second protection means (9).  15 - Device according to one of claims 12 to 14, characterized in that the second protection means (9) are similar to those (7) according to claims 6 to 11.  16 - Support and abutment means, in particular for the connection device according to one of claims 1 to 15, comprising two identical elongated half-supports (3a, 3b) hollowed out with first longitudinal grooves (31a, 31b) accommodating the ends of optical fibers (2a, 2b) butted two by two of two sets (la, lb) and two second longitudinal grooves (32), two cylinders (33), and flexible fasteners (35a, 35b) pressing the two cylinders (33) in the second grooves (32) for aligning the first grooves (31a, 31b) of the half-supports, characterized in that they comprise means (36) integral with the half-supports (3a, 3b) for pushing one against the other the transverse edges (30) of the half-supports (3a, 3b) at the ends of the fibers to be butted.  17 - Means according to claim 16, characterized in that the means for pushing the half-supports comprise a longitudinal piece (36) having two flexible bent ends (362a, 362b) which are applied by their own opposite flexions against the distant transverse edges (37a, 37b) of the half-supports (3a, 3b).  18 - Means according to Claim 17, characterized in that the means for pushing the half-supports comprise a longitudinal plate (38) comprising a cavity (380) against transverse walls from which the elbows of the flexible ends bear (362a, 362b) of the longitudinal part (36).  19 - Mcyens according to one of claims 16 to 18, characterized in that the sides of each groove (32, 33) of the half-supports (3) have two parallel rectilinear edges (A1, A2; Fig. 7) against which is supported by an optical fiber (2) or a cylinder (33).  20 - Means according to one of claims 16 to 19, in which the half-supports (3a, 3b) are parallelepipedic and have one of their large faces hollowed out with first grooves (31a, 31b) parallel and rectilinear containing coplanar optical fibers (2a, 2b) coming from two assemblies (la, Ib) in which the fibers have a distribution with axial symmetry, characterized in that they comprise means (Ra, Rb) integral with the carrier means (12a, 12b ) sets of optical fibers (la, lb) to transform the distribution with axial symmetry (13) of the fibers in the sets into the coplanar distribution along the first grooves (31a, 31b) of the half-supports (3a, 3b).