MXPA06008744A - Re-enterable splice enclosure - Google Patents

Abstract

A re-enterable enclosure for a splice between cables, comprises two cover members (1, 3) with internal walls that are configured to form a cavity (7, 9) for enclosing the cable splice when the cover members (1, 3) are engaged with each other in a closed position. At least one of the cover members also has internal walls (15, 17) that are configured to define containment spaces which at least partly surround the cavity (7, 9). In use, those containment spaces may contain sealant material (27). At least one internal wall in one cover member can telescope into a containment space in the other cover member so that, if sealant material is contained therein, it will be compressed when the cover members are engaged with each other in the closed position. By changing the containment spaces that are used to contain sealant material (27), different levels of protection against humidity can be provided for the cable splice in the cavity.

Description

Declarations upder Rule 4.17: For two-letter cades and other abbreviations. rfr to the "Guid- - a to the applicant's entitlement to effel for the benefit of eleven Notes on Codes and Abbreviations" appearing at the beginning of the patent (Rule 4.17 (ü)) for all designations of a regular issue to the PCT Gazette. a to? ie applicant 's entitlement to claim the priority of the earlier application (Rule 4.17 (iü)) for all designations Published: RE-ENTRABLE SPLICE BOX FIELD OF THE INVENTION The present invention relates to a box for the connection between cables, the box is of the type that can be reopened, re-entrable, which allows access to the cable splice when required and, preferably, that be subsequently resealed. The cable could be, for example, a telecommunications cable, an electric power cable or a fiber optic cable. The cable splice could be, for example, a splice extending in the longitudinal direction (ie, a splice between cables extending, generally, from the opposite directions) or the so-called splice? twisted threads ", or butt joint splice (ie, a splice between cables that extends, generally, from" the same direction).

BACKGROUND OF THE INVENTION A cable splice will, in general, require protection against the effects of the environment in which it is located and, more specifically, will require protection against mechanical impact and moisture entry. Often, protection of the cables against elongation or deformation will also be required. Many different boxes REF. 174893 provide different levels of protection for cable splices that are already available, which include so-called re-tradable boxes that can be reopened to allow access to the splice whenever required. Frequently, the known re-insertion boxes can be reopened, which defines a cavity around the splice and contains a sealing material. The housing provides protection for the splice against mechanical impact and, in combination with the sealing material, protects the cavity to a required level against moisture ingress while allowing access to the splice when the housing is reopened. In some cases, the cavity is completely filled with sealing material (see for example, the junction boxes described in U.S. Patent No. 6, 169,250 and, in other cases, the sealing material is pre-formed to through molding in particular shapes for use in cable bushings that are located at the ends of the housing (see, for example, the junction boxes described in WO 02/063736).

SUMMARY OF THE INVENTION The present invention is directed to providing a re-engageable junction box that is capable of providing adequate protection for cable splicing against mechanical impact and moisture ingress without requiring the cavity surrounding the splice to be filled with some suitable sealing material 5. and without requiring that the sealing material be preconfigured in comparatively complex forms for use in cable bushings. Accordingly, the invention is also directed to provide a re-engageable junction box that is capable of providing adequate protection for the cable splice against mechanical impact and moisture ingress, while using a comparatively small amount of splice material. sealed and while it is comparatively simple to assemble. The present invention provides a reclosable box-re-5 for a cable splice, the box comprising two cover members with internal walls that are configured to form a cavity for enclosing the cable splice when the cover members are engaged with each other. in a closed position, wherein: (i) at least one of the cover members has internal walls that are configured to define containment spaces, which are suitable for maintaining the sealing material that surrounds, at least partially, the cavity and (ii) ) at least one internal wall in a cover member can be compressed or retracted into the containment space in the other cover member, whereby any sealing material contained therein is compressed when the cover members are engaged with each other in the closed position. Advantageously, at least one of the cover members comprises protection members against them. pulls associated with the cable entry pathways within the cavity. Then, the box is capable of supplying the splice with protection against the effects of deformation or stretching of the cable in addition to what is provided, by means of the members. of cover, against mechanical impact and that provided, through the cover members, in combination with any sealing material in the containment spaces, against the entry of moisture.

Brief Description of the Figures. By way of example only, the junction boxes according to the invention will be described with reference to the accompanying figures, in which: - Figure 1 is a perspective view of a -box of. example splice -in an open condition, showing-the. inside of the members of -cover; Figure 2 is a front view of the junction box of Figure 1 in the direction of arrow II; - "Figure 3 is an enlarged view of one end of one of the cover members of Figure 1. Figure 4 is similar to Figure 1 although it shows another example splice box with sealing material contained in the members. Figure 5 shows a longitudinal cross-section taken along line 5-5 of the junction box of Figure 4 in a closed condition, Figure 6 shows the junction box of Figure 4 in a condition open and ready to be closed around a cable splice; Figure 7 is similar to Figure 1 and shows the sealing material contained in the cover members; Figure 8 is a cross-sectional view of the splice box Figure 7 in the direction of arrow 8-8, Figure 9 is a front view of an enlarged scale of part of the junction box illustrating a modified hinge, and Figure 10 is a perspective view of yet another junction box in a condition n open, showing the interior of the cover members.

Detailed Description of the Invention Figure 1 shows two elongated members - of cover 1, 3 which are used, in the manner to be described below, to form a cylindrical protection box for a longitudinal cable splice (not shown). The cover members 1, 3 are molded components, which are formed from a suitable plastic material, for example, polypropylene or polyamide and are bonded together along their inner longitudinal edges 2 by a joint 5. As shown in FIG. illustrated, the joint 5 is integrally molded with the cover members 1, 3 and comprises a region of reduced thickness that defines the axis of flexion of the joint. This type of joint is well known and is often referred to as a "direct" joint. Both of the cover members 1, 3 include internal walls (described in more detail below) that define the central cavity regions 7, 9, respectively. When the cover members 1, 3 are folded together around the joint 5 and are clutched together to close the junction box, the cavity regions 7, 9 together form a central enclosed cavity for the containment of the cable splice that will be protected. To hold the cover members 1, 3 together in the closed position, the engagement tongues 11 protrude upwardly from the interior of the outer longitudinal edge 10 of the upper cover member 1, so that they will slide towards the latching space 10a behind the outer longitudinal order 10 of the lower cover member 3 and they will engage in the respective recesses 12. Furthermore, in order to reduce the possibility of any relative movement between the cover members • '!, - 3, - once these are found. in the closed position, the lower cover member 3 is provided with the bolts 13 which engage in the openings 14 in the upper cover member 1. In this way, the stress placed on the joint 5 when the junction box is find in use, it is limited and the risk of the latching tabs 11 being disengaged inadvertently from the holes 12. The region of. cavity 7 in the upper cover member 1 is defined between the side walls 15 and the double end walls .17 that rise from the inner surface of the cover member. The side walls 15 are located slightly inside the inner and outer longitudinal edges 2, 10 of the cover member, and extend parallel to. the same. The end double walls 17 extend between the ends of the side walls 15 and are located at a distance from the respective ends 19 of the cover member 1, whereby a space 20 is created at each end of the cover member. Top deck; each of these spaces 20 is intended to be used, when the junction box is in use, to accommodate a respective vertical structure for protection against cable pulls 21 formed at the corresponding end of the lower cover member 3. The protective structures against pulls 21 will be described later. The space 17A between the two walls of each end double wall 17 provides a containment space for the sealing material, as will also be described below. The cavity region 9 in the lower cover member 3 is defined between the side walls 22 and the end walls 23 that rise from the inner surface of the cover member. The side walls 22 are also slightly located on the inside of the inner longitudinal edge 2 of the cover member and the inner wall 10B of the latching space 10A, and extend parallel thereto. The end walls 23 extend between the ends of the side walls 22 and each is located at a distance from the respective pull-protection structure 21. In this way, the spaces that are formed around the region of cavity 9, on the outside of the side and end walls 22, 23, provide the containment spaces for the sealing material, as will be described below. The side walls 15 and the double end wall 17 of the cavity region 7 in the upper cover member 1 are raised above the level of the outer edge of the cover member and are located, so that when the cover members 1 , 3 are folded-together towards the closed position, the walls 15, -17 will be retracted into the containment space around the cavity region 9 in the lower cover member 3.. The guides or cable entry ways to the junction box are further defined by the semicircular recesses 25B in the end walls of the cover member 1 and the end wall 17 of the cavity region 7. Next, with reference to Figure 3, which is an enlarged view of one end of the lower cover member 3, it can be seen that each pull protection structure 21 comprises three separate walls 25, located in parallel to the adjacent end 19 of the cover member inferior.3. The. aredes 25 contain the cable holes 25A which are displaced from each other to define a convolute cable entry path within the junction box. The cable entry ways - to the junction box are ... additionally defined - by the semicircular recesses 25b in the end walls of the cover member 3 and the. end wall 23 of the cavity region 9. Associated with the recesses 25b on the end walls 23 are the optional surfaces 26 which guide the cable into the cavity region 9 and provide - additional protection against jerks , if required. The junction box, which comprises the cover members 1, 3, can be used without the addition of some sealing material (ie, in the manner shown 'in Figure -1 and in Figure 3) to In order to provide a basic level of protection against 'moisture' for a longitudinal splice between two cables, in addition to the 'protection against mechanical impact and the' stretching or deformation of the cable. The cable splice is first prepared, and subsequently, the cables are placed on the lower cover member 3 with the splice by itself located in the cavity region 9 and the cables extending away from the opposite ends of the spider member. cover along the paths defined by the holes 25a in the pull-out protection structures 21, and the recesses 25B in the walls 19, 17 and 23. Next, the upper cover member 1 is folded on the lower cover member 3, around the joint 5, and is hooked in the closed position. Now, the cable splice is protected against mechanical impact and, up to a basic level, against moisture through the cover members 1, 3 although it can nevertheless be easily accessed by unhooking the upper cover member and move it to the open position. The convoluted pathways of. Cable that are defined through holes 25A provide protection against cable pulls, and guarantee the integrity of the splice. With reference to Figure 4, if the cable splice required a higher level of protection against moisture, the sealing material 27 would be provided in the containment spaces at the ends of the cavity regions 7, 9. To ensure, in the case of the cavity region 9, that the sealing material 27 is retained within the containment spaces at the ends of the cavity (and that it does not enter the containment spaces on the sides), the walls 23 of the member The lower cover 3 would be extended outward at each end in order to provide the barriers or protections 23A. As a consequence, the recesses 15A are cut in the upper parts of the pairs 15 of the upper cover member 1 to accommodate the upper parts ^ of the protections 23A when the junction box is closed. Then, the cable splice is prepared and the cables are placed on the lower cover member 3 as described above and as illustrated in Figure 6, which shows the box of Figure 4 during the process of being used for protect the longitudinal splice between the two cables 28. The cables are shown comprising two pairs of wires 28A (although this is not essential) and are located on the lower cover member 3, so that the connections 28B between the individual wires 28A of a cable and the connections of another cable 'are located within the cavity region 9 with the cables 28 extending from the opposite ends thereof, along the defined paths through the holes 25A in the protective structures against pulls 21, and recesses 25B on walls 19 and 23. Next, the junction box is closed as described above, whereby, the upper parts is of the protections 23A in the lower cover member 3 are located in the respective recesses 15A in the upper cover member 1. At the same time, the double walls 17 at the ends of the cavity region 7 (with the sealing material 27 between them) will be retracted within the sealing material 27 at the ends of the cavity region 9 as illustrated in Figure 5, which shows a longitudinal-central cross section of the junction box from which the cables have been omitted for reasons of clarity. As a result, the sealing material 27 at both ends of the inner cavity of the junction box is compressed and brought into effective sealing contact with the cables and the adjacent surfaces of the members. cover. Depending on their nature, the sealing material could also tend to flow out of the containment spaces and along the outside of the cables to a limited extent, thereby increasing the sealing effect. Now, the cable splice is protected to a higher level against moisture and, in the same way as before, against the mechanical impact and the stretching or deformation of the cable, although it can still be quickly accessed simply by unhooking the limb from the cable. top cable and move it to the open position. The sealing material 27 for the box of Figure 4 could be provided in the form of pre-configured pieces of gel which are located in the containment spaces of the ends of the cavity regions 7, 9. Alternately, the sealing material could be provided in liquid form, in such case, it is poured into the containment spaces, and is cured at this site until it has a gel-like consistency before use. Any tendency for the material, sealing liquid to spread out of the containment spaces through the adjacent recesses 25A, 25B may be limiting. by using a high sealing material, viscosity with a short curing time .. With reference to Figure 7, if the cable splice. would still require a higher level of protection against moisture, additional sealing material 29 could also be provided in the containment spaces along the sides of the cavity region 9 before - the spliced cables are placed 'on the lower cover member 3 as described above. In this case, the barrier or protection 23A and the associated recesses 15A-of-Figure 4 are not required and can be omitted. Then, the junction box is closed as described above, by means of which, the side walls 15 of the cavity region 7 as well as the double end walls 17 (with the sealed 27 between them) will be retracted within the sealing material 29, 27, respectively, on the sides and ends of the cavity region 9 as illustrated in the cross-sectional views of Figures 5 and 8 As a result, the interior cavity. of the junction box is surrounded by the compressed sealing material and the junction box is still protected up to a higher level against moisture (and, in the same way as before, against the mechanical impact and the stretching or deformation of the cable) although it can still be easily accessed simply by unhooking the upper cover member and moving it to the open position. As described previously, the sealing material 27, 29 for the box of Figure 7 could be provided in the form of pre-configured pieces of gel which are located in the containment spaces at the ends of the cavity region. 7, and at the ends and sides of the cavity region 9. Alternatively, the sealing material could be provided in liquid form, in which case, it is poured into the containment spaces and cured in this way. place until you get a gel-like consistency before use. A particular advantage of the junction boxes comprising the cover members 1, 3 as described above, is that a type of box can be used to provide various levels of protection against moisture simply by the inclusion of a sealing material in the proper locations within the cover members. Instead, the junction box illustrated in Figure 4 can be used to provide three different levels of protection that are illustrated in Figures 1, 4 and 7 despite the fact that the 23A protections are not required in each case . For each level of moisture protection, effective protection is also provided for the splicing against impact - mechanical and cable stretching. The junction boxes are simple-built, and use, in comparative form, some components, so that they are easy to assemble in the field, even in difficult or inaccessible locations. The modification required to change the level of protection (ie, the addition of sealing material) can be easily performed by the manufacturer or the installer, in particular, when a liquid sealing material is used because there is no need of dispensing pieces of gel that are preformed in a particular configuration. The maximum amount of sealing material (Figure 7) needs to be used only when absolutely necessary and is still smaller than that used, for example, in re-attachable splice boxes in which the totality of the splice cavity is filled with sealing material. Accordingly, the costs of the splice boxes comprising the cover members 1, 3 as described above, may be lower than those in which the entire splice cavity is filled with sealing material. In addition, it 'made that the cavity regions 7, 9 are empty allows' what a larger number of joints are accommodated within the single box; in addition, better environmental conditions are provided in which the long-term splice (s) is located; and simplifies access to the junction (-s) in case the box is reopened. Because only one sealing material is used in the junction boxes shown in Figures 4 and 7 of the figures, there are no sealing problems associated with the interconnections between the different sealing materials (e.g. sealing materials 27, 29 in Figure 7 or at the junction between the sealing materials 27 in the upper and lower cover members 1, 3). In addition, the particular construction of the junction box (which, as described, causes the end double walls 17 in the upper cover member 1 and the sealing material 27 contained therein to retract within the sealing material. 27 in the lower cover member 3 when the box is closed) ensures that the cables 28 are completely surrounded by the sealing material 27 in the immediately outer region of the central cavity 7, 9 of the box. Therefore, the possibility of air spaces around the cables in these locations would be eliminated, which could happen if the sealing material 27 in the upper cover member 1 were simply in face-to-face contact with the material. of sealing 27 in the lower cover member and which, if present, would allow the moisture to penetrate the central cavity 7, 9. Preferably, the sealing material 27, 29 has sufficient long-term elasticity to ensure, once that it has been compressed by the closing of the cover members 1, 3, that the effective seal is maintained until the junction box is reopened. Advantageously, the sealing material allows the junction box to be then resealed (and if required, opened and resealed once more on several occasions) and continues to provide the same level of protection for the cable splice. A suitable sealing material is disclosed in our co-pending United States Patent Application Serial No. 10 / 770,095, filed on February 02, 2004, entitled "MICROSPHERE-FILLED SEALANT MATERIALS", and which is incorporated in the present as a reference. However, if one or more external elastic members are required, these may be located in a known manner at suitable positions on the cover members 1, 3 to apply the compressive force required in the sealing material when the box is closed. of splicing. It will be appreciated that various modifications to the construction of the cover members 1, 3 could be made without affecting the protective function of the junction box. In one modification, the single articulation 5 between the two cover members 1, 3 is replaced by two articulations 5A, 5B as illustrated in Figure 9. This modification allows the junction box to be closed by the movement of each cover member only through S0 ° relative to the adjacent joint, thereby reducing the stress placed on each joint. When a single joint 5 is employed, as shown in Figure 2, it is not essential that the joint be integrally molded with the cover members; as an alternative t, this could be a separate component in the form, for example, of a film or a tape that is an insert molded or bonded by adhesive. It is also possible to modify the shape, location and number of the hooks 11, 12 which are used to hold the cover members together in the closed position. The provision of protective structures against pulls 21 in the junction box, while convenient, will limit the size of the cable with which the junction box can be used. For use with larger diameter cables, the pull protection structures 21 may be omitted and conventional cable joints may be used instead. In alternate form, the pull-protection structures 21 can be designed to accommodate the larger diameter cables with which the junction box is intended to be used, and some additional mechanism can be provided to allow the box to be used with diameter cables smaller. Figure 10 shows, for example, a "junction box" in which each of the pull protection structures 21 is designed to accommodate a five-wire cable, and the cover member 3 is extended at each end in order to provide compartments 30 in which smaller diameter cables (eg, two pair cables) can be secured using conventional cable joints For this purpose, each compartment 30 is provided with a seat 32 that is aligned with the orifice cable 25A of the adjacent pull-protection structure 21 and provides support for the cable that enters <; the junction box. If the cable is too small to be adequately secured through the strain relief structure 21, it can be secured in the seat 32 through a cable joint (not shown) that is passed around the cable and the seat through an opening 34 in the cover member 3. With the benefit of the teachings of this patent, a person skilled in the art could apply the present invention to any wire size or any pair account. In the junction box shown in the Figure , the cover member 1 is also extended at each end to the same extent as the cover member 3, so that the compartments 30 containing the seats 32 will be closed when the cover members 1, 3 are closed • around a cable splice. In a modified version, the cable seats 32 can simply be provided as extensions of the cover member and can remain exposed when the splice box is closed. Figure 10 also shows a further modification of the junction box, in the form of 'two areas of cut or weakness 36 in the cover member 3 (one within each of the compartments 30) -which can be pierced by screws to allow the box to be secured on a flat surface, if required. * As a further alternative, the positions for the screws can be provided in the extensions of the cover member 3, so that they remain exposed and accessible when the junction box is closed. Figure 10 further illustrates that all cable holes / recesses 25A, 25B, in the walls of the containment spaces at the ends of the cavity regions 7, 9, are closed by means of the wall portions capable of be broken 25 before use of the junction box. These wall portions 26 allow the liquid sealing material to be poured into the containment spaces up to the level of the top of the walls and to be retained during curing. From here on, due. to which the wall portions 2 ^ can be broken, these will be removed by the action of placing a cable in place in the associated holes / recesses 25A, 25B-, whereby, the cable is allowed to be embedded effectively in. the sealing material. Similar portions of wall susceptible to being broken could be used in any of the other junction boxes described above with reference to the drawings. Figure 10 also shows the provision of a raised continuation 40 adjacent to the joint 5 on the middle wall of each nail 'of the pull-out protection structures 21. Each of the raised continuations 40 can be engaged in an opening respective 41 on the other side of the • joint in the cover member 1, in order to provide additional protection for the joint when the cover members 1, 3 are closed. It will be further appreciated that the box -empalme of the same general type that those illustrated in the drawings could be used to protect the so-called "twisted-wire" splice or the joint-to-top splice. (ie, a splice between the extending cables, generally, from from the same direction, rather than from the opposite directions as shown in Figure €) 'In this case, the junction box (which includes the structures of' protection against shooting 21) would require its modification to allow the cables to enter the box, generally, from the same direction, rather than from opposite directions as illustrated in the drawings. Further modifications of the cable entry ways of any of the junction boxes described above with reference to the drawings would allow protection to be provided for the junctions between the different numbers of cables, for example, a longitudinal splice between a cable which extends from one direction and two cables that extend from the other direction. It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims (23)

1. CLAIMS Having described the invention as above, the content of the following claims is claimed as property: 1. A re-entrable box for a cable splice, characterized in that it comprises: a first and a second cover member with internal walls that are configured to form a cavity enclosing the cable splice when the cover members are engaged together in a closed position, wherein: (i) at least one of the cover members has internal walls that are configured to define spaces of containment, which are suitable for maintaining the sealing material surrounding, at least partially, the cavity and (ii) at least one internal wall in a cover member can be compressed or retracted within the containment space in the another cover member, whereby the sealing material contained therein is compressed, when the cover members are clutched together in position closed 2. The junction box according to claim 1, characterized in that the internal walls are configured to define the containment spaces surrounding the cable entry pathways within the cavity, and where the cable tracks traverse the -spaces. of containment. 3. The junction box according to claim 2, characterized in that the containment spaces are defined by the internal walls in both cover members. The junction box according to claim 1, characterized in that there are internal walls configured to define the containment spaces in both cover members, and in which a containment space in a cover member can be retracted within the space of containment on the other cover member, for compressing the sealing material enclosed in both containment spaces when the cover members are clutched together in the closed position. 5. The junction box according to claim 1, characterized in that none of the containment spaces contain sealing material. The junction box according to claim 2, characterized in that the containment spaces contain sealing material. The junction box according to claim 1, characterized in that at least one of the containment spaces contains a sealing material that has been poured into the containment space and subsequently cured. 8. The junction box according to claim 1, characterized in that all containment spaces contain the same sealing material. The junction box according to claim 1, characterized in that the cavity 'enclosing the cable splice is essentially free of sealing material. 10. The junction box in accordance with. claim 2, characterized in that at least one of the cover members comprises pull-protection members associated with the cable entry ways. . 11. The junction box according to claim 1, characterized in that the cavity is of an elongated shape, and the junction box comprises cable entry paths within the cavity from opposite ends of the same. . . 12. The junction box according to claim 11, characterized in that the internal walls are configured to define transverse containment spaces at the opposite ends of the cavity. -. 13. The junction box according to claim 12, characterized in that the cable entry passages cross the transverse-containment spaces. 14. The junction box according to claim 13, characterized in that the transverse containment spaces are defined by the internal walls in both cover members. , 15. The junction box according to claim 14, characterized in that the internal walls defining the transverse containment spaces in one cover member can be retracted into the containment transverse spaces in the other cover member in order to compress the sealing material enclosed in the containment transverse spaces when the cover members are clutched together in the closed position. The junction box according to claim 12, characterized in that the internal walls in at least one of the cover members are configured to provide longitudinal containment spaces that extend along both sides of the cavity between the ends opposite of it. The junction box according to claim 16, characterized in that the internal walls "in the other cover member can be retracted within the longitudinal containment spaces in order to compress the sealing material contained therein, when the Cover members are clutched together - in the closed position. 18. The junction box according to claim 16, characterized in that none of the containment spaces is essentially free of sealing material. 19. The compliance junction box with claim 16, characterized in that the containment transverse spaces contain sealing material. 20. The junction box according to claim 19, characterized in that the longitudinal containment spaces contain sealing material. 21. The junction box according to claim 1, characterized in that the cover members are joined together at least through a joint. 22. The junction box according to claim 1, characterized in that the. Cover members can be clutched together releasably. 23. The junction box according to claim 1, characterized in that the cover members are molded components.