SYSTEM FOR DOCKING CABLES TO THE HOUSING OF AN OPTICAL SPLICE BOX

Description

[0001] The invention relates to a system for securing a cable to the container of an optical splice box, in particular for an optical fiber network. Such a box is used throughout the network, in an optical distribution frame, in a waterproof or aerial box, between the telephone exchange and the destination building.

[0002] An optical splice box, in particular for a fiber optic network, is essentially made up of an outer container, and, inside the container, a support organizer, with several cassettes each carrying several splices. The container has at least one cable entry port, framed by, inside a tubular base, and outside the container, a nut screwed onto the tubular base. The cables passing through the entry port are manually secured to securing supports secured to the bottom of the container, in the shape of a finger or T. The operation of securing a cable requires clamping the cable sheath, the carrier and the aramid or glass strands, on the securing supports, by means of metal or plastic collars, to ensure good resistance of the secured cable, to traction and compression.

[0003] The securing of the carrier is generally separate from that of the aramid strands. Since securing operations are manual, as the number of cables increases, the accessible volume at the bottom of the container reduces, and it becomes increasingly difficult to secure a cable.

[0004] Document US 5,793,921 A discloses the preamble of claim 1.

[0005] Document US 2009 / 087158 A1 discloses a device for constraining fiber optic cables.

[0006] An aim of the invention is to propose a cable securing system in an optical splice box, which allows securing operations to be carried out practically without constraints linked to the available volume.

[0007] The invention relates to a cable securing system according to claim 1.

[0008] Other features are defined in the dependent claim. Brief description of the drawings

[0009] The invention is described below with reference to the accompanying drawings which represent: [ Fig. 1 ] a perspective view of an exemplary embodiment of a base for a cable lashing system according to the invention; [ Fig. 2 ] a perspective view from the outside of a mooring support according to a first embodiment useful for understanding the invention; [ Fig. 3 ] a perspective view of the interior, of the mooring support of the Fig. 2 ; [ Fig. 4 ] a perspective view from the outside of a lashing ring for the lashing bracket of the Fig. 2 ; [ Fig. 5 ] a perspective view of the interior of the lashing ring of the Fig. 4 ; [ Fig. 6 ] a perspective view of the first embodiment of a cable lashing system; [ Fig. 7 ] a perspective view of a lashing support according to a second embodiment, this one according to the invention; [ Fig. 8 ] a perspective view of the second embodiment of a cable securing system according to the invention.

[0010] According to the invention, the base 1, fixable by the nut 2 to the cable entry port in the container, has an axial passage 3 for the cables ( Fig. 1 ). The base 1 is three-dimensional, it has a cylindrical perimeter 4, not necessarily of revolution, comprising several arches 5 regularly distributed on the cylindrical perimeter 4. The average geometric axes of the arches 5 are parallel to each other and parallel to the geometric axis of the base. Each arch 5 has two lateral branches 6 separated by a longitudinal opening 7 and joined by a vertex 8. Over a part of their height close to the vertex 8, the lateral branches 6 of each arch have their external surfaces parallel. At the base of the longitudinal opening 7, the base 1 has a slot 9.

[0011] In the first embodiment not forming part of the invention, the cable securing device consists of a securing support ( Fig. 2 , Fig. 3 ) and a lashing ring ( Fig. 4, Fig. 5 ). The mooring support 10 comprises at its lower end a base 11 for bearing on the base 1 and a tab 12 intended to be inserted into the slot 9 of the base 1 to ensure the stability of the position of the mooring support on the base 1. The mooring support 10 has a lower part 13 capable of receiving a collar for fixing the sheath of a cable against its inner face 14, which is fitted with ribs 15 for retaining the sheath of the cable.

[0012] The lashing support 10 has a central part 16 comprising a belt 17 releasing a lower opening 18 capable of receiving a hoop 5 of the base 1. The belt 17 has, above the opening 18, a cutout defining a finger 19 having a certain elasticity. The finger 19 carries on its inner face, a notch 20 for snapping under the top 8 of the hoop 5.

[0013] The lashing support 10 has an upper part 21 ensuring the function of lashing the cable in cooperation with a lashing ring 22 ( Fig. 4, Fig. 5 ). On its inner face 23, the upper part 21 of the lashing support 10 has a hollow profile, and on its opposite face, it carries a cylindrical guide 24 for a screw 25 carried by the lashing ring 22.

[0014] The lashing support 10 carries at its upper end two elastic fins 26 capable of deforming when the lashing ring 22 is inserted on the upper part 21 of the lashing support 10, and then of preventing the lashing ring 22 from leaving the lashing support 10 until it is in the lashing position.

[0015] The lashing ring 22 ( Fig. 4, Fig. 5 ), is of substantially square section to allow it to be placed on the upper part 21 of the mooring support 10. On one 27 of its outer faces, it has a thread 28 allowing it to carry a screw 29. On the opposite face, it has a hollow profile 30, capable of cooperating with the hollow profile of the inner face 23 of the mooring support to ensure the mooring of the cable.

[0016] The base 1 with its hoops 5 is placed in the container of the optical splice box, at the right of a cable entry port, and it is fixed there by screwing the nut 2 outside the container. Each cable to be secured arrives through the axial passage 3 of the base 1.

[0017] The end of the cable is prepared in a conventional manner by removing the outer sheath, cutting the aramid strands and the carrier, braiding the aramid strands and terminating with a knot. The lashing device is then freely presented at the end of the cable. The inner face 14 of the lower part 13 of the lashing bracket 10 is applied against the end of the cable sheath and a clamp is placed around the cable sheath and the lower part 13 of the lashing bracket 10. The carrier and the aramid strands are arranged between the hollow profile of the inner face 23 of the upper part 21 of the lashing bracket, and the hollow profile 30 of the lashing ring 22. The optical fiber of the cable is not introduced into the lashing ring. The aramid strands, beyond the lashing ring 22, are looped around the fins 26.

[0018] The screw 29 is then poured into the thread 28 and it bears on the bottom of the guide 24, which, by reaction, makes the lashing ring 22 move back perpendicular to the longitudinal axis of the lashing support, ensuring the clamping of the carrier and the aramid strands between the hollow profile of the inner face 23 of the upper part 21 of the lashing support 10 and the hollow profile 30 of the lashing ring 22. The aramid strands, after looping around the fins 26, are brought back towards the sheath of the cable and the clamp ensures the clamping of the sheathed end of the cable and the end of the aramid strands. The lashing of the cable on the lashing support 10 is thus ensured.

[0019] The lashing device is then brought closer to the base 1. The lower part 13 of the lashing support 10 is inserted into the base 1, against a hoop 5. The belt 17 of the central part 16 of the lashing support 10 is positioned on the hoop 5 by sliding. During this sliding, the tongue 12 at the lower end of the lashing support 10 enters the slot 9 of the base. During sliding, the latching notch 20, carried by the finger 19 of the belt 17, slides on the outer contour of the top 8 of the hoop 5, pushing the finger 19 outwards.

[0020] At the end of sliding, the notch 20 ensures the snap-fastening under the top 8 of the hoop 5, and the base 11 of the mooring support comes to rest on the base 1. The cable mooring operation is then completed.

[0021] The lashing device has a reduced number of parts (a lashing bracket, a lashing ring and a screw), ensuring both the clamping of the cable carrier, the looping and clamping of the aramid strands, and the tightening of the cable and the aramid strands by a collar on the lashing bracket. Once the cable is secured on the lashing device, it is placed on the base by snapping, practically without interaction with other elements of the optical splice box. The presence of several snap locations on the base makes it possible to maintain satisfactory alignment of the cables with respect to the entry port in the event of installation of several cables in the same entry port ( Fig. 6 ).

[0022] According to the second exemplary embodiment, forming part of the invention ( Fig. 7 And Fig. 8), the lashing device consists of a lashing support 31, a crosspiece 32 and a fixing screw 33. The lashing support 31 is flat, U-shaped, each branch 34 of the U carrying at its outer edge a notch 35 for snapping onto a hoop 5 of the base 1. The lashing support 31 is sized to be snapped onto two opposite hoops 5 of the base 1. The crosspiece 32 is substantially parallel to the base 36 of the U. It has two ends 37 bent towards the base 36 of the U and guided by slots 38 in the base 36 of the U. The fixing screw 33 cooperates with a thread 39 in the base 36 of the U to bring the crosspiece 32 towards the base 36 of the U.

[0023] The securing bracket 31 carries, near the end of one of the branches 34 of the U, on the inner edge of the branch, a flap 40 for clamping the cable. The flap 40 is located in a plane distinct from the general plane of the U-shaped securing bracket so as to free the cable entry port. Indeed, this embodiment of the cable securing device for an optical splice box is more particularly oriented towards a cable of large transverse dimension relative to the entry port.

[0024] In this embodiment, the carrier and the aramid strands are clamped between the crosspiece 32 and the base of the U of the lashing support 31, and the cable and the aramid strands are clamped by a collar on the clamping flap 40. Once the cable has been secured to the lashing device, the latter is brought closer to the base and the lashing support 31 is arranged diametrically, between two opposite hoops 5 of the base 1, and lowered towards the cable entry port. The outer edges of the ends of the branches 34 of the U have oblique sides 41 which cause the tops 8 of the hoops 5 intended to receive the lashing device to move outwards.

[0025] When the latching notches 35 have passed the inner side of the top 8 of the hoops 5, the hoops 5 return to their rest position and the latching is ensured, thus completing the securing of the cable.

[0026] The advantages of the cable securing system to the container of an optical splice box according to the invention include in particular: to be able to easily handle the parts without local constraints; to prepare and put in place the cable elements (carrier and aramid strands) with two hands; to tighten these elements without external assistance in terms of equipment or personnel, with a simple screwdriver; to loop the aramid strands without constraints to secure them at the same time as the cable sheath on the mooring support with the same collar.

Claims

1. System for anchoring a cable to the container of an optical splice enclosure, having: - a plinth (1) that can be fastened to the port for entry of the cables into the container, having an axial passage (3) for the cables, having a cylindrical perimeter (4) having a plurality of arches (5), which are distributed over said cylindrical perimeter and of axis parallel to the axis of the plinth; - and at least one cable anchoring device, independent of the plinth (1), and able to be fastened to the plinth by mechanical cooperation with at least one arch (5) of the plinth (1), characterized in that the anchoring device is constituted of a flat U-shaped anchoring support (31) and a crossmember (32) substantially parallel to the base (36) of the U, this crossmember having two bent ends (37) guided by slots (38) in the anchoring support; and a screw (33) for fastening the crossmember (32) to the base (36) of the U, so as to ensure the anchoring, each of the branches (34) of the U bearing on the outside a catch (35) for snap-fastening to an arch (5) of the plinth, the anchoring support being dimensioned so as to be snap-fastened onto two diametrically opposite arches of the plinth.

2. Cable anchoring system according to Claim 1, characterized in that the anchoring support bears, near the end of one of the branches (34) of the U, on the inner edge of the branch, and in a plane that is distinct from the general plane of the U, a flap (40) for restraining the cable.