WO2000049697A1

WO2000049697A1 - Device for protecting splices

Info

Publication number: WO2000049697A1
Application number: PCT/FR2000/000383
Authority: WO
Inventors: Jean-Louis Delatouche
Original assignee: Corning Cable Systems S.A.
Priority date: 1999-02-17
Filing date: 2000-02-16
Publication date: 2000-08-24
Also published as: CA2349680A1; CN1348622A; FR2789816A1; FR2789816B1; BR0007044A; AU2678200A

Abstract

The invention concerns a device for protecting splices, characterised in that it comprises two substantially semi-cylindrical identical half-shells respectively delimited on either side by two longitudinal bearing surfaces (4) whereby they are urged to press against each other, so as to define at their inside part a groove (10) for receiving cables, at the splices and ensure longitudinal tightness of the device around the splices and, two sealing washers having a diameter corresponding to the receiving groove (10) cross-section provided with a series of median orifices (23) for passing theretrough the cables to be connected thereby ensuring transverse tightness around the splices.

Description

“Splice protection device” The subject of the present invention is a device for protecting splices, in particular splices of telephone cables. Such devices are conventionally installed at the junction of cables to protect the wire connections from chemical attack from the outside environment as well as from the mechanical stresses to which they may be subjected. These protection devices can be used for cables installed in underground pipes, in the ground, in the air or on the facade of buildings.

They must meet a certain number of requirements, in particular to be impermeable to gases and water both in immersion (use in underground pipes) and against water runoff (aerial or facade use) and have sufficient mechanical strength to allow exerting, within certain limits, tensile, bending or twisting forces on the cables. It is, moreover, essential that these devices are chemically neutral with respect to possible aggressions from the environments of use (chemical neutrality with respect to a basic medium (pH13) and an acidic medium (pH1 ), or vis-à-vis exposure to UV rays or vis-à-vis hydrocarbons, for a limited period).

To meet these requirements, protection devices in the form of sleeves are conventionally provided consisting of two essentially semi-cylindrical half-shells made of synthetic material and closed at their ends by flanges or plugs shaped to the diameter of the cables. To seal between the half-shells, provision is made to insert a seal made of synthetic material or putty between them; the assembly thus formed is generally blocked around the cables by an elastic closure member applied to the external face of the half-shells.

To complete the sealing of the protection device thus formed, it has already been proposed to garnish the half-shells, at their internal part, of a polymeric sealing material which can, advantageously, be in the form of a gel in which the cables are embedded.

A protection device of this type is, by way of example, described in publication WO-93/14547.

Such devices are entirely satisfactory from the point of view of their resistance to the stresses to which they may be subjected, but have the drawback of requiring the adoption of a planar and non-voluminous splicing plane and in addition of being particularly expensive taking into account the number of elements constituting them and especially the cost of the sealing material which is, as a general rule, constituted by a particularly expensive resin. The object of the present invention is to remedy these drawbacks by proposing a device for protection of splices, in particular splices of telephone cables, inexpensive and quick to install, while being sufficiently resistant to external aggressions both chemical and mechanical. According to the invention, this device is characterized in that it comprises, on the one hand, two identical half-shells essentially semi-cylindrical respectively delimited on either side by two longitudinal bearing faces by which they come s' apply one against the other, so as to define at their internal part, a cable receiving channel, at the level of the splices, and to ensure the longitudinal sealing of the device around the splices and, on the other hand, two closing washers with a diameter corresponding to the cross-section of the reception channel fitted with a series of median orifices allowing the passage of the cables to be connected and ensuring the transverse sealing of the device around the splices.

In accordance with the invention, the closing washers consist of hollow parts, generally made of plastic, which are filled with a polymer material, in particular a gel or an elastomer of polyurethane type capable of to be pierced by the cables to be connected and flush with the outside, on the one hand, at the level of the orifices for the passage of these cables and, on the other hand, at the level of at least one peripheral annular recess.

In addition, the half-shells are equipped at their internal part, at the respective ends of the receiving channel, with essentially semi-circular transverse moldings allowing the positioning of the closing washers and cooperating with the peripheral annular recesses thereof so as to move and deform the polymeric sealing material and seal the device at this level.

According to another characteristic of the invention, one of the bearing faces of the half-shells or first bearing face comprises over substantially its entire length a groove filled with a sealing material, in particular of a putty, while the other bearing face or second bearing face is equipped with a corresponding rib, also over essentially its entire length, the rib of one of the half-shells cooperating with the groove of the other half-shell so as to displace and deform the sealing material and to ensure the longitudinal sealing of the device around the splices.

Such a device can receive a large number of cables; it is essentially distinguished by the presence at its central part of a closed volume receiving the splices which is closed off by sealing zones filled with polymer gel or putty and is thus sufficiently protected against external aggressions. The quantity of sealing material required in accordance with the invention is much lower than that used in the devices of the prior art in which the internal part of the protective sleeve is entirely filled with such a material.

It should also be noted that the sealant ensuring the longitudinal seal is significantly less expensive than the polymer gel ensuring the transverse seal. According to the invention, the support faces generally have a width of the order of 4 to 10 mm.

In the particular case of the connection of telecommunication cables, the semi-cylindrical shells can advantageously be constituted by ^" elements of polypropylene or other synthetic material having a width of 5 to 10 cm for a length of 20 to 60 cm. The depth of the grooves is on average of the order of 4 to β mm while the height of the ribs is of the order of 2 to 3 mm.

According to the invention, when the two half-shells are applied one against the other by their bearing face, the ribs, penetrating into the grooves located opposite move and deform the sealing material, in particular the putty, which allows to guarantee and maintain permanent contact between it and the ribs and therefore to obtain a barrier ensuring the longitudinal tightness of the closed volume present in the internal part of the sleeve vis-à-vis liquids and gases. According to another characteristic of the invention, the bearing faces of the semi-cylindrical half-shells are fitted, along their external edge, with alternately male and female snap-in connecting members, intended to cooperate in pairs to block the device around cables at the touch of a button.

It is of course necessary that when the half-shells are positioned opposite each side of the cables each male member cooperates with a female member and vice versa. According to another characteristic of the invention, the bearing faces are each equipped with at least one hooking ring.

This ring allows the attachment and in particular the suspension of the device for example on a facade. The essential characteristic of the device which is the subject of the invention is however linked to the nature of the means used to guarantee the transverse tightness around the splices and in particular to the prior filling in the factory of the closing washers with a material d '' sealing in the form of a flexible gel essentially incompressible with high elongation characteristics. This gel undergoes, in fact, a first displacement and deformation constraint during its drilling by the cables to be connected which are passed through it before making the splices and thus tends to be evacuated towards the exterior at the level of the peripheral annular recesses.

It then undergoes a second constraint of the same type when, after the splices have been made, the device is closed following the application of the two half-shells against each other by their respective bearing faces: in fact, the transverse moldings then penetrate into the annular recesses located opposite so as to repel the sealing gel; this makes it possible to guarantee and maintain permanent contact between it and the transverse moldings, and consequently, to obtain a barrier ensuring transverse sealing of the closed volume present in the internal part of the device vis-à-vis liquids and gases.

This barrier is all the more effective the greater the rate of deformation of the polymer sealing gel, therefore the contact forces between this material and the cables, on the one hand, and the transverse moldings, on the other. hand, are important.

According to a preferred characteristic of the invention, each of the closing washers is constituted by the association of two identical half-washers arranged head to tail and preferably assembled to one another by snap-fastening members.

It should be noted that the two half-washers can, if necessary, be pre-assembled in the factory. According to another particularly advantageous characteristic of the invention, each closing half-washer is constituted by a circular plate pierced with the median orifices allowing the passage of the cables to be connected and the internal face of which is equipped with a peripheral flange and is extended by flexible strips extending radially ment from the peripheral flange between orifi ^¬ these median. In accordance with this configuration, the two half-shells have the shape of cylinders, one of the lateral faces of which is immediately adjacent to the peripheral flange is made of gel and are assembled at the level of these gel faces.

It should be noted that during this assembly, the gel also undergoes a prior displacement and deformation stress of the same type as those to which it is subjected during its drilling by the cables to be connected and when the half-shells are closed.

According to the invention, the flange of each half-washer can advantageously have a width of the order of 1 to 2 cm, which makes it possible to guarantee the presence of a sufficient mass of gel inside the hollow washers.

According to the invention, it is advantageous to subdivide the median orifices into a central orifice surrounded by a series of peripheral orifices uniformly distributed over one. circle and respectively separated by a flexible strip; these strips then constitute radial partitions delimiting compartments which can each receive one of the cables to be connected which can thus be perfectly embedded in the gel.

According to another characteristic of the invention, the median orifices consist of baleen having a star-shaped configuration.

This characteristic makes it possible to ensure optimum maintenance of the gel inside the device and, consequently, to guarantee maximum contact between the gel and the cables to be connected.

According to another characteristic of the invention, the peripheral flange comprises a main annular part secured to the internal face of the circular plate and an auxiliary annular part separated from the main annular part by a peripheral annular recess of determined width and fixed to it. here by the. flexible strips which have a recess at the level of this recess. According to another characteristic of the invention, the half-shells are equipped at each end of the receiving channel with four parallel transverse moldings regularly spaced apart, namely on the one hand, two internal moldings capable of penetrating into the peripheral annular recesses of the half -closing washers to ensure transverse sealing of the device and, on the other hand, two external moldings having the function of guaranteeing the positioning of these closing half-washers around the splices.

The characteristics of the device which is the subject of the invention will be described in more detail with reference to the accompanying drawings, in which:

- Figure 1 is a perspective view of a half-shell, - Figures 2 is a bottom view of the half-shell shown in Figure 1,

FIG. 3 is a section through a half-shell by a transverse plane shown diagrammatically by the axis III-III (FIG. 2),

FIG. 4 is a detail showing the cooperation of the ribs and grooves fitted to the bearing faces,

FIG. 5 is a bottom view of a closing half-washer before filling it with gel,

- Figure 6 is a sectional view of the half-washer shown in Figure 5, along the axis VI-VI, - Figure 7 is a sectional view of the half-washer shown in Figure 5, according to l 'axis VII-VII,

- Figure 8 is a side view of two half-washers placed side by side.

According to Figure 1, the splice protection device consists of two half-shells 1, the strictly identical, having a central portion 2 essentially semi-cylindrical delimited on either side by longitudinal bearing faces 3 , 4.

The two half-shells 1, l 'are applied one against the other by their bearing faces 3, 4, so that the semi-cylindrical middle parts 2 define between them, at their internal part, a receive channel 10 δ

cables at the splices not ^" shown (figure 2).

According to Figures 2 and 3, a first bearing face 3 has a groove 5 which extends essentially over its entire length. The second bearing face 4 is, for its part, equipped with a rib 6 corresponding to the groove 5 and also extending over substantially its entire length.

As shown in Figure 4, when the two half-shells 1, l ', are positioned facing each other around the cables at the splices, the groove 5 of one of the half-shells cooperates with the rib 6 of the other the half-shell and vice versa.

According to Figure 4, the groove 5 of each half-shell is filled with a sealing material A in particular with a putty put in place by casting.

The introduction of a rib β in the mass of material A, in the position shown in Figure 4, causes a displacement and a deformation of this mass A, thus ensuring the longitudinal seal between the two half-shells 1 , the, around the splice not shown.

Furthermore and according to Figure 1, the bearing faces 3, 4 of the half-shells 1, l 'are equipped along their edges with snap-fit connecting members 20, 21 alternately male and female which cooperate in pairs to block the half-shells 1, the around the cables by simple pressure.

The half-shells are, moreover, provided on their bearing face 3, 4 with hooking rings 22 allowing them to be fixed in particular on a facade.

According to Figure 2, the half-shells 1, l 'are equipped, at their internal part at their respective ends, with four transversely moldings 8, 9 regularly spaced, namely two internal moldings 8χ, 9 and two moldings external 82, 92; these moldings have the function of cooperating with hollow closing washers 11 shown in FIGS. 5 to 8 to ensure lateral sealing of the device in a manner which will be described in more detail later in this presentation.

According to FIG. 8, each closing washer 11 is constituted by the association of two identical half-washers 12, 13 arranged head to tail and fixed to one another by snap-fastening members 14, 14 '.

In a manner not shown in the figures, the entire internal volume of the half-washers 12, 13 is filled with a polymeric sealing material in the form of an essentially incompressible gel having high elongation characteristics. .

According to FIGS. 5 to 8, each closing half-washer 12, 13 is constituted by a circular plate 15 the internal face of which is surrounded by a peripheral flange 16 and which is extended by flexible strips 24 (six in number in the example shown in the figures) independent of each other; these strips 24 extend radially from the peripheral flange 16 so as to subdivide the internal volume of the half-washers 12, 13 into six radial compartments of the same dimensions.

The flange is further subdivided into a main annular part 17 integral with the internal face of the plate 15 and an auxiliary annular part 18 separated from the main annular part 17 by a peripheral annular recess 19 of determined width, and fixed to that -ci by the flexible strips 24 which have a recess 25 at this recess (Figure 7).

According to FIG. 5, the circular plate 15 is pierced with median orifices 23 which allow the passage of the cables to be connected, not shown. These orifices 23 consist of baleen having a star-shaped configuration and are distributed in a central orifice surrounded by six peripheral orifices respectively located in one of the compartments delimited by the radial lamellae 24. This configuration is not, well understood, in no way limiting the invention.

In view of the above, each half-washer 12, 13 is in the form of a rem- gel ply, one of the lateral faces of which is immediately adjacent to the peripheral flange 16 is made of gel; the latter is also flush with the outside at the middle orifices 23 of the circular plate 15 and at the peripheral recess 19.

Furthermore and as shown in FIG. 8, the width e of the auxiliary annular part 18 of the flange 16 is equal to half of the width E of the main annular part 17 thereof; consequently, after assembly of the two half-washers 12, 13 by means of the snap-fastening members 14, 14 ′, a closing washer 11 is obtained comprising three annular parts of the same dimensions separated by two peripheral annular recesses 19 filled with gel. According to Figures 2 and 8, after closing the two half-shells 1, I N these recesses 19 cooperate with the internal semicircular transverse moldings 8] _, 9χ to ensure the transverse tightness of the device.

This cooperation can largely be assimilated to the cooperation of the ribs 6 with the putty A filling the grooves 5 shown in FIG. 4: in fact, the internal transverse moldings 8, 9 penetrate into the gel filling the peripheral annular recesses 19 of the washers 11 in causing displacement and deformation of this gel.

The external transverse moldings 8 ₂ , 9 ₂ make it possible to guarantee correct positioning of the closing washers 11 around the splice.

Claims

1 °) Device for protecting splices, in particular telephone cable splices, characterized in that - it comprises, on the one hand, two half-shells (1, identical INs essentially semi-cylindrical respectively delimited on the part and d 'other by two longitudinal bearing faces (3, 4) by which they are applied one against the other, so as to define at their internal part, a cable receiving channel (10), at the level splices and to ensure the longitudinal sealing of the device around the splices and, on the other hand, two closing washers (11) of diameter corresponding to the section of the receiving channel (10) equipped with a series of median orifices (23) allowing the passage of the cables to be connected and ensuring the transverse sealing of the device around the splices, - the closing washers (11) are constituted by hollow parts filled with a material of polymer seal, in particular of a gel liable to be pierced by the cables to be connected and flush with the outside, on the one hand, at the passage openings (23) of these cables and, on the other hand part, at at least one peripheral annular recess (19), and - the half-shells (1, l ') are fitted at their internal part, at the respective ends of the receiving channel (10), with moldings transverse essentially semicircular (8, 9) allowing the positioning of the closing washers (11) and cooperating with the peripheral annular recesses (19) thereof so as to displace and deform the polymeric sealing material and to ensure the transverse sealing of the device at this level.

2) Device according to claim 1, characterized in that one of the bearing faces (3) of the half-shells (1, l ') or first bearing face comprises on essentially the totali- tee of its length a groove (5) filled with a sealing material (A), in particular a putty, while the other bearing face (4) or second bearing face is equipped with a corresponding rib (6), also over substantially its entire length, the rib (6) of one of the half-shells (1, IN cooperating with the groove (5) of the other half-shell so as to move and deform the sealing material (A) and ensure the longitudinal sealing of the device around the splices.

3 °) Device according to any one of claims 1 and 2, characterized in that each of the closing washers (11) is constituted by the association of two identical half-washers (12, 13) arranged head to tail.

4 °) Device according to claim 3, characterized in that the two closing half-rings (12, 13) are fixed to each other by snap-fastening members (14, 14 ').

5 °) Device according to any one of claims 3 and 4, characterized in that each closing half-washer (12, 13) is constituted by a circular plate (15) pierced with the median orifices (23) allowing the passage of cables to be connected and the internal face of which is equipped with a peripheral flange (16) and is extended by flexible strips (24) extending radially from the peripheral flange (16) between the median orifices (23) .

6 °) Device according to any one of claims 1 to 5, characterized in that the median orifices (23) consist of baleen having a star-shaped configuration. 7 °) Device according to any one of claims 5 and 6, characterized in that the peripheral flange (16) comprises a main annular part (17) integral with the internal face of the circular plate (15) and an auxiliary annular part (18) separated from the main annular part (17) by a peripheral annular recess (19) of determined width and fixed to the latter by flexible strips (24) which have a recess (25) at this recess.

8 °) Device according to claim 7, characterized in that the half-shells (1, IN are equipped at each end of the receiving channel (10) with four parallel transverse moldings (8, 9) regularly spaced, namely on the one hand, two internal moldings (8] _, 9χ) capable of penetrating into the peripheral annular recesses (19) of the closing half-washers (12, 13) to ensure the transverse sealing of the device and, on the other hand share, two external moldings (8 ₂ - 9 ₂ ) having the function of guaranteeing the positioning of these closing half-washers (12, 13) around the splices.

9 °) Device according to any one of claims 1 to 8, characterized in that the bearing faces (3, 4) of the semi-cylindrical half-shells are equipped along their external edges with snap-fit connecting members ( 20, 21) alternately male and female intended to cooperate in pairs to block the positive ^¬ around the cables by simple pressure.

10 °) Device according to any one of claims 1 to 9, characterized in that the bearing faces (3, 4) are each equipped with at least one hooking ring (22).