MXPA97004238A - Splice enclosure for enterra telecommunication cables - Google Patents

Abstract

The present invention relates to an environmentally sealed splice enclosure (20) for buried telecommunication cables (32) and splices (33), includes a base (22a and b) having gates (31a and b) for receiving the cables of telecommunications (32) through them. A cover (25) is received on the base (22) to form a cavity (50) inside the splice enclosure (20). The cavity (50) is filled with a gel sealer (45 and 47). A dome (55) on the end of the lid (25) opposite the base (22) accommodates the volumetric and pressure changes inside the enclosure (2).

Description

SPLICE ENCLOSURE FOR BURIED TELECOMMUNICATION CABLES Reference to Related Requests This application is a partial continuation of the United States of America Patent Application Serial Number 60 / 005,072 filed October 6, 1995, now Background of the Invention The present invention relates to splice enclosures, and more particularly to an environmentally sealed splice enclosure for telecommunication cables that achieves a reliable and durable environmental seal after an easy installation that does not require the use of heat. The invention is particularly suitable for use with buried cables, service wires, and their associated splices, including situations where it may be desirable to be able to enter the enclosure to regain access to the splices. Protecting the environment from telecommunication splices is an old problem. In essence, the challenge has been to isolate the splice from any material that could degrade its quality, including these materials oxygen, water, salts, and so on. From a theoretical point of view, this is not so difficult: simply build a fortress around the splice enough to keep all these pollutants out. However, from a commercial point of view, there is a continuing need for splice sites that are extremely easy to use, extremely effective in excluding contaminants, and extremely economical. In recent years, significant advances have been made through the use of gel sealants. The adhesive properties of these gels easily seal the gels to the substrates to be protected, and preclude the access of contaminants to them. The elasticity of the gels allows them to conform to even very complex geometrical requirements, and because the gels do not harden over time, they can accommodate later configuration changes if a prior provision is made for the same. Gels have proven to be particularly useful and valuable where it may be necessary to re-enter electrical contacts and / or splices subsequently. This technology has therefore significantly improved performance, while also significantly reducing costs and complexity. However, there is still room for important improvements. For example, more and more services are being installed below, instead of above, the ground. In the telecommunications industry, splices for these cables must be protected very reliably, and yet, in the interest of the economy, protection must be provided in a fast, convenient, and economical manner. Therefore, an enclosure to contain and protect these splices should be as close to self-installation as possible. It should also be versatile, since the number of splices that will be accommodated can vary significantly (typically from maybe four connections to as many as twelve or more). Changes in environmental conditions (mainly temperature and hydrostatic pressure by immersion) must also be accommodated. An easy re-entry should also be provided in case it is needed subsequently. Accordingly, there remains a need for better methods and apparatus for environmental sealing of telecommunication cable splices in underground environments, and particularly for providing reliable cold-sealed enclosures for burying splices.

SUMMARY OF THE INVENTION Briefly, the present invention meets the foregoing needs, and is proposed, with a new improved environmentally sealed splice enclosure for buried telecommunication cables (including copper wire cables, coaxial cables, fiber optic cables, etc.), achieve a reliable and long-lasting environmental seal without the use of heat or toxic chemicals. The enclosure is easily assembled from only three pieces: a two-part base and a lid. Essentially, after these splices are completed, the two halves of the bases are instantly clamped together around two wires, the splices are configured around the upper surfaces of the complementary gel plugs of the base, and the cover snaps instantly On the base. Then the enclosure is placed in its underground location (buried directly, or inside another enclosure), and the work is finished. To achieve this convenience, the present invention includes a pair of gates on the base that are sized to closely fit the wires to be passed through them. In the preferred embodiment, the gates are partially closed by flexible tabs or fingers which produce an opening effect to accommodate different sizes of cables. Each base portion also includes a fastener for coupling and retaining the cables, the fasteners having fingers between which the cables are received, and tips on the fingers in such a way that they can slide one over the other to interdigitate as the halves are brought together from the base. Above the gates are two complementary gel portions that seal around the cables to form a block to moisture when the base sections are snapped together. The complementary lid contains a third portion of gel, whose volume, when added to the two gel portions of the base, fills the cavity defined by the assembled lid and base. The splices themselves are thus completely engulfed in the gel between the lid portion and the base portions. To accommodate the internal and external volumetric and pressure changes for the essentially closed cavity of the splice chamber, the upper part of the lid, opposite the base, a flexible dome bladder. The dome is initially (before assembly) concave outward, and then subsequently bulges upward or outward according to the additional volume engulfed in the cavity resulting from the cables and splices enclosed therein. Subsequently, the dome will also flex in response to changes in sealant pressure, such as resulting from thermal expansion and contraction. A main feature of the present invention is that the dome is formed of a suitable plastic material that relaxes in a substantially non-elastic manner over time, to return the pressure of the sealant inside the cavity of the enclosure to the ambient pressure, and to accommodate and balance changes in environmental pressure. This several advantages. For example, significant differences in the volume of cables and splices can be easily accommodated without the need to expel excess gel, or the need to maintain a pressure or energy storage device, or a constant pressure, regardless of significant volume variations. Instead, sealing to the environment is based on the adhesive properties of the gel rather than on the compression of the gel. Another advantage, which results from relying on the adhesion of the gel, is that it is not necessary to guarantee the operation of a pressure or energy storage device over a period of years. Instead, the present invention engulfs the cables and splices in a sufficient amount of gel, provides compensation for the volumetric and pressure variations described above, and ensures that the gel remains substantially at ambient pressure over time, so as to achieve a reliable long-term environmental seal. Accordingly, it is an object of the present invention to provide new and improved methods and apparatus for splicing enclosures sealed to the environment for all types of telecommunication cables.; these methods and apparatuses that provide and utilize an environmentally sealed splice enclosure for buried telecommunications cables, the enclosure including a base having gate elements that define at least one inlet gate to receive at least one telecommunications cable through of the same, a cover that has at least one wall and that can be received on the base opposite the gate element to complement the base in order to form with it a cavity inside the splice enclosure, dimensioning the base, the gate element, and the lid, such that the cavity is substantially isolated from the outside of the enclosure when the inlet gate element is blocked by one or more cables passing through it, filling a previously determined volume of sealant substantially the cavity, and an element of volumetric adjustment and pressure in the room to automatically compensate the variations i) in the volume of the cables and fittings installed in the enclosure to ensure that the sealant continues to substantially fill the cavity, and ii) in the sealant pressure resulting from the expansion and thermal contraction thereof, and the pressure changes external, to ensure that the sealant continues to substantially fill the cavity, substantially at ambient pressure, to achieve a reliable and durable environment seal for cables and splices within it; wherein the volumetric and pressure accommodating element can be a flexible bladder that relaxes substantially in a non-elastic manner, - wherein the bladder can be a dome in the splice enclosure; wherein the dome may be integral with a lid wall; which may include a protective ring having an outer rim, the ring projecting outwardly from the outside of the cap substantially opposite the base, and wherein the dome is substantially in and below the rim of the protective ring to protect the dome at least during the assembly of the cover on the base, - wherein the protective ring may be substantially circular, - wherein the dome may be concave outwards before the assembly of the cover on the base; wherein the sealant may be a suitable gel for sealing to the environment telecommunications connections; wherein each portion of the base and the cover can include a respective complementary portion of the gel, between which portions of gel cables and fittings can be accommodated when the enclosure is assembled around it, to effect a block of environmental water, to protect these joints; which may include at least one fastener on the base in the gate member for engaging and retaining cables passing therethrough, the fastener having a plurality of fingers configured to interdigitate with another fastener by becoming closely opposed to it, and an element of flexion to facilitate the reception of a cable between the fingers by providing the fingers with an elastic fold away from each other; which may include an element to expel substantially all of the air and / or moisture from the cavity during the assembly of the lid on the base; and to realize the above objects and purposes in an economical, non-complicated, durable, versatile, and reliable method, and apparatus, economical to manufacture, and easily adapted for the widest possible utilization in the environment-sealed buried cables, wires service, and its associated splices. These and other objects and advantages of the invention will become clearer from the following description, the accompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS Figures la and Ib are top and bottom perspective views of an assembled enclosure in accordance with the present invention. Figure 2 is a bottom view of the enclosure of the Figure 1. Figure 3 is a cross-sectional view of the enclosure, taken generally on line 3-3 of Figure 2. Figure 4a is a view partially broken away in parts of the enclosure. Figure 4b is a view completely separated in parts of the enclosure. Figure 5a illustrates the dome in the enclosure lid before assembly. Figure 5b illustrates the dome in the lid of the enclosure after assembly, showing the flexure to accommodate the volumes of material therein. Figure 6 is a top plan view of a base portion. Figure 7 is an elevated view of the base portion of Figure 6, taken on line of sight 7-7 of Figure 6. Figure 8 is an elevated view of the base portion of Figure 6, taken on line of sight 8-8 of Figure 6. Figure 9 is a bottom view of the base portion shown in Figure 6. Figure 10 is a plan view of the lid. Figure 11 is an elevated view of the lid. Figure 12 is a partially part separated view showing a preferred configuration for the splices. Figure 13a is a perspective view of the fastener.

Figure 13b is a perspective view of the fastener opposite that shown in Figure 12. Figures 14a and 14d illustrate the progressive expulsion of air between the gel portions during the assembly of the lid on the base.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, the new and improved environment sealed junction enclosure 20 for telecommunication cables will now be described, and the method for sealing to the environment cables and telecommunication splices buried in accordance with this invention. Figure 1 shows the splice enclosure 20, comprised of a two-part base 22a and 22b, and a cover 25. The base portions 22, in the preferred embodiment, are identical and are configured to be joined in a complementary fashion when They juxtapose face to face. This is facilitated by the securing bolts 27 which are received in the respective slots 28 to instantaneously hold the halves of the base 22 together. On the bottom of the halves of the base, there are pairs of empty gates 31a and b for receiving the cables 32 therethrough. The conductors inside the cables 32 are electrically and mechanically coupled in the conventional manner by the splices 33. The gates 31 are partially closed by flexible tabs or fingers 34, which produce an opening effect to accommodate different sizes of cables. Supported adjacent gates 31 are fasteners 35a and 35b having fingers 36, which form slots 37 therebetween, where cables are received. The sides of the fingers are shaped like saw teeth to hold the cables. The tips of the fingers 39 are bent slightly upwards over a pair, and slightly downwards over the mirror image pair, to be configured to complement each other for convenient interdigitation when they oppose when the base halves 22 snap into place. each. The cables 32 are easily accommodated in the slots of the fastener 37 by the provision of a flexing element 41, which allows the fingers to bend easily in an elastic manner away from each other to enlarge the slot 37. In the preferred embodiment, the bending element 41 is a hole in the back portion of the fastener which bridges the fingers on each side of a corresponding slot 37, such that the material in that region is reduced, thus allowing it to flex more easily. Each base half portion 22a or 22b has a respective gel portion 45a or 45b, and as shown, they are face to face with the wires 32 passing between them to the upper portion (lid 25) of the splice enclosure 20. The base portions of the gel 22 in this manner provide a block of water environmentally effective to protect the joints 33. The gel can be any suitable gel to seal to the environment telecommunications connections, as is known in the art. The lid of the splice chamber 25 contains a third portion of gel 47 which, in combination with the volumes of the gel base portions 45a and b, is added to a volume of gel sealant that substantially fills the cavity 50 (Figure 3) which is formed inside the lid and the base when they are joined together. Preferably, the splices 33 are formed on top of the gel base portions 45a and b, spaced apart from each other as illustrated in Figure 12, and then individually individually engulfed in the gel between the portions of gel base 45a and b and the gel cap portion 47 when the lid is assembled on the base. To accommodate variations in the volumes of the cables and splices, and variations in gel volume resulting from thermal expansion and contraction, the upper part of the lid 25 is formed as a bladder in the form of a flexible dome 55 which is integral with the top wall of the lid. The dome 55 is initially concave outward, and, depending on the volume displacement that needs to be accommodated during assembly, it will be pushed out a little from that initial shape. (It can even become convex). At least the dome 55 is made of a suitable material such as polypropylene, which relaxes in a substantially non-elastic manner, such that the pressure inside the cavity 50 is restored and maintained at external ambient pressure. Therefore, the dome 55 is a pseudo-piston for transmitting external pressure (eg, external hydrostatic pressure) to the interior of the enclosure 20, so that there is less incentive for water to leak into the enclosure. Figures 14a-14d illustrate the progressive expulsion of air from between the gel portions during the assembly of the lid on the base. As seen (Figure 14a) the upper profiles 65a and 65b of the gel base portions 45a and 45b, do not engage with the profile 67 of the gel cap portion 47. Instead, the profiles are configured to causing the gel portions 65 and 67 to make contact with one another initially in the center. Then, as the lid of the closure 25 continues to assemble on the base 22, the contact between the gel portions 65 and 67 moves progressively outward, as shown in sequence in Figures 14b and 14d. This expels substantially all trapped air and / or moisture out of the cavity 50, through the fine perimeter gap 70 where the base 22 and the cover 25 meet. In the preferred embodiment, the dome 55 is surrounded by a protective ring 58 having an outer flange 59. The protective ring projects outwardly from the outside of the cap substantially opposite the base 22, and the dome 55 is substantially in and below the outer flange 59. In this way, the The dome can be protected during the assembly of the lid on the base, such as by inverting the enclosure to compress the base in the lid. In some situations, the protective ring 58 will also provide protection for the dome 59 after installation under the floor. The base 22 is held on the lid 25 (and vice versa) by the instantaneous adjustment fingers of the base 62, which are received in the finger slots of the lid 63 when assembled in this manner. Accordingly, as can be seen, the present invention provides numerous advantages. Mainly, as the tests have shown, it provides a convenient, economical splice enclosure, highly reliable, and efficient for buried telecommunication cables. As will be appreciated now, the present invention can be assembled quickly, usually in a few minutes, regardless of whether a few splices or many splices are to be enclosed, and without worrying about the precise volume of the cables inside the enclosure. No special tools are required, although, if desired, assembly and disassembly can be facilitated by a properly configured lever (not shown) to reduce the manual force required. No heat or toxic chemicals are required. No time is required for the materials to solidify or harden. With the cables installed through, and thus blocking, the base gates, the cavity inside the enclosure is substantially isolated from the outside of the enclosure. Another advantage of the present invention is that it can be easily re-entered if it becomes necessary or desirable to regain access to the cables and / or splices thereof. The instantaneous adjustments of the enclosure are simply released, which can be easily done in a manual way or with a suitable lever (for example, a screwdriver), and immediate access is provided. When reassembled, protection of the entire environment is immediately restored. Of course, the experts in this field will think about different modifications to the present invention when reading the present description. For example, a bladder other than a dome may be used on the end of the lid, as desired. Additional cable gates can be provided. A screen or protector can be added to the protective ring over the dome to reduce the exposure of the dome to solid objects after the enclosure is buried. The dependencies of the claims have been drafted to comply with TCP Rule 6.4, but it will be understood that, at least by virtue of this paragraph, any appropriate combination of the features described and / or claimed herein is itself a modality of the invention, and it is intended to use multiple dependent claims in the national phase where they are allowed. Accordingly, although the methods and apparatus forms described herein constitute the preferred embodiments of this invention, it should be understood that the invention is not limited to those methods and precise forms of apparatus, and that changes can be made therein without depart from the scope of the invention.

Claims (24)

1. An environmentally sealed splice enclosure for buried telecommunication cables, which comprises: a) a base having a gate element defining at least one input gate to receive at least one telecommunications cable therethrough, b) a cover that has at least one wall, and that can be received on the base opposite the gate element to complement the base in order to form with it a cavity inside the splice enclosure, c) dimensioning the base, the gate element, and the cover in such a way that the cavity is substantially isolated from the outside of the enclosure when the entry gate element is blocked by one or more cables passing through it, d) a previously determined volume of sealant which substantially fills the cavity, and e) a volumetric and pressure accommodation element in the enclosure to automatically compensate for variations: i) in the volume n of the cables and fittings installed in the enclosure, to ensure that the sealant continues to substantially fill the cavity, and ii) the sealant pressure resulting from the expansion and thermal contraction of the cavity, and changes in external pressure, for ensure that the sealant continues to substantially fill the cavity, substantially at ambient pressure, to achieve a reliable and durable environmental seal for cables and splices within it. The splice enclosure of claim 1, wherein the volumetric and pressure accommodating member further comprises a flexible bladder that relaxes in a substantially non-elastic manner. The splice enclosure of claim 2, wherein the bladder further comprises a dome in the splice enclosure. 4. The splice enclosure of claim 3, wherein the dome is integral with a cover wall. The splice enclosure of claim 4, further comprising a protective ring having an outer rim, this ring projecting outward from the outside of the cap substantially opposite the base, and wherein the dome is substantially in and under the rim of the protective ring to protect the dome at least during the assembly of the cover on the base. The splice enclosure of claim 5, wherein the protective ring is substantially circular. The splice enclosure of claim 5, wherein the dome is concave outward prior to the assembly of the cover on the base. The splice enclosure of claim 1, wherein the sealant is a gel suitable for sealing telecommunications connections to the environment. The splice enclosure of claim 8, wherein each portion of the base and the cap includes a respective complementary portion of the gel, between which portions of gel cables and splices are accommodated when the enclosure is assembled around it, for effect a block of environmental water to protect those joints. The splice enclosure of claim 1, which further comprises at least one fastener on the base in the gate member, for coupling and retaining the cables passing therethrough, this fastener having: a) a plurality of fingers to receive at least one of those cables between them, b) tips on the fingers, configured to interdigitate with another fastener when they are closely opposed to it, and c) a flexing element to facilitate the reception of a cable between the fingers by arranging that the fingers flex in an elastic manner away from each other. The splice enclosure of claim 1, wherein the predetermined volume of sealant further comprises an element for expelling substantially all of the air and / or moisture from the ceivity during assembly of the cap on the base. 1

2. A splice enclosure sealed to the environment for buried telecommunication cables, which comprises: a) a base having a gate element defining at least one input gate to receive at least one telecommunications cable therethrough, b) a cover having at least one wall, and it can be received on the base opposite the gate element to complement the base in order to form with it a cavity inside the joint enclosure, c) dimensioning the base, the gate element, and the cover in such a way that the The cavity is substantially isolated from the outside of the enclosure when the entry gate element is blocked by one or more cables passing through it, d) a previously determined volume of sealant that substantially fills the cavity, this sealant being a suitable gel for sealing to the environment telecommunications connections, each portion of the base and lid including a respective complementary portion of the gel, between which portions of gel are they accommodate cables and splices when the enclosure is assembled around them, to effect a block of environmental water to protect these splices, including this sealant an element to expel substantially all the air and / or humidity from the cavity during the assembly of the lid on the base, e) a flexible pressure and volumetric accommodation dome that is integral with a lid wall, which is concave outward prior to the lid assembly on the base, and relaxes substantially not elastic to automatically compensate for variations: i) in the volume of cables and fittings installed in the enclosure, to ensure that the sealant continues to substantially fill the cavity, and ii) in the sealant pressure resulting from the expansion and thermal contraction thereof , and changes in external pressure, to ensure that the sealant continues to substantially fill the cavity, substantially at ambient pressure, f) a substantially circular protective ring having an outer rim, this ring projecting outward from the outside of the cap substantially opposite the base, and wherein the dome is substantially in and below the rim of the protective ring to protect the dome at least during the assembly of the cover on the base, and g) at least one fastener on the base on the gate member, for coupling and retaining the cables passing therethrough, this holder having: i) a plurality of fingers to receive when less to one of those cables between them, ii) tips on the fingers, configured to interdigitate with another fastener when they are closely opposed to it, and iii) a flexing element to facilitate the reception of a cable between the fingers when arranging the fingers bend in an elastic way away from each other. to achieve a reliable and durable environment seal for cables and splices inside it. 1

3. A method for sealing buried telecommunication cables and splices to the environment, which comprises: a) enclosing the cables and splices in a cavity inside a splice enclosure, the enclosure having a base, a gate element in the base which defines at least one input gate to receive at least one telecommunications cable therethrough, a cover having at least one wall and that can be received on the base opposite the gate element, to complement the base for the purpose of forming the cavity inside the splice chamber, the base, the gate element, and the lid being dimensioned in such a way that the cavity is substantially isolated from the outside of the enclosure when the input gate element is blocked by one or more cables that pass through it, b) substantially fill the cavity with a previously determined volume of sealant, c) automatically compensate for variations: i) in the volume of cables and fittings installed in the enclosure, to ensure that the sealant continues to substantially fill the cavity, ii) the sealant pressure resulting from thermal expansion and contraction thereof, and changes in external pressure, to ensure that the sealant continues to substantially fill the cavity, substantially to environmental pressure, to achieve a reliable and durable environmental seal for buried telecommunications cables and splices. The method of claim 13, wherein the compensating step further comprises relaxing a flexible bladder in a substantially non-elastic manner. 15. The method of claim 14, wherein the compensating step further comprises relaxing a bladder in the form of a dome in the splice enclosure. The method of claim 15, wherein the compensating step further comprises relaxing a dome that is integral with a lid wall. The method of claim 16, which further comprises protecting the dome at least during the assembly of the cover on the base with a protective ring having an outer flange projecting outwardly from the outside of the cap substantially opposite to the base, and wherein the dome is substantially in and below the rim of the protective ring. 18. The method of claim 17, which further comprises protecting the dome with a protective ring that is substantially circular. The method of claim 17, wherein the compensating step further comprises relaxing a dome that is concave outward before assembling the lid on the base. The method of claim 13, wherein the filling step further comprises filling the cavity with a gel sealant which is suitable for sealing the telecommunications connections to the environment. The method of claim 20, wherein the filling step further comprises filling each portion of the base and the cover with respective complementary portions of the gel, between which portions of gel cables and fittings are accommodated when the enclosure is assembled to its around, to effect a block of environmental water to protect these joints. The method of claim 13, wherein further comprising engaging and retaining the wires passing through the base with at least one fastener on the base in the gate member, the holder having: a) a plurality of fingers to receive at least one cable between them, b) tips on the fingers, configured to interdigitate with another fastener when opposing them closely, and c) a flexing element to facilitate the reception of a cable between the fingers when arranging the fingers they bend in an elastic way moving away from each other. 23. The method of claim 13, which further comprises expelling substantially all of the air and / or moisture from the cavity during assembly of the lid on the base. 2

4. A method for sealing buried telecommunication cables and splices to the environment, which comprises: a) enclosing these cables and splices in a cavity inside a splice enclosure, the enclosure having a base, a gate element in the base which defines at least one input gate to receive at least one telecommunications cable therethrough, a cover having at least one wall and which can be received on the base opposite the gate element, to complement the base with the In order to form the cavity inside the splice chamber, the base, the gate element, and the cover are dimensioned in such a way that the cavity is substantially isolated from the outside of the enclosure when the entry gate element is blocked by one or more cables which pass through it, b) substantially fill each portion of the base and lid with respective complementary volumes previously determined from a sealed or gel that is suitable for environmentally friendly telecommunications connections, between which gel volumes are then accommodated the cables and splices when the enclosure is assembled around it, to effect a block of environmental water to protect these splices, c) to expel substantially all the air and / or moisture from the cavity during the assembly of the lid on the base, d) by non-elastic relaxation of a flexible dome that is integral with a lid wall and that is concave outwards from the lid assembly on the base, automatically compensate variations: i) in the volume of cables and fittings installed in the enclosure, to ensure that the sealant continues to substantially fill the cavity, and ii) in the sealant pressure resulting from the thermal expansion and contraction thereof, and changes in the external pressure, to ensure that the sealant continues to substantially fill the cavity, substantially at ambient pressure, e) protect the dome at least during the assembly of the lid on the base, with a substantially circular protective ring having an outer flange projecting outward from the outside of the lid substantially opposite the base, the dome being substantially in and below the rim of the protective ring, and f) coupling and retaining the cables passing through the base, with at least one fastener on the base in the gate element, the fastener having: i) a plurality of fingers to receive at least one cable therebetween, ii) tips on the fingers, configured to interdigitate with another fastener when opposing them closely, and iii) a flexing element to facilitate the reception of a cable between the fingers, by arranging that the fingers bend elastically away from each other. to achieve a reliable and durable environmental seal for buried telecommunications cables and splices.