Aerial splicebox for fiber optic cables

An aerials splicebox for optic fiber cables is provided which includes: a base, the peripheral wall which is provided with bottom windows and top windows and an external flange articulating a cover provided with a surrounding flange; a belt to be fitted on said flanges, when situated against each other; a ring-shaped handle having a closed end, hinged in the first end of the belt and a bipartite opposing end which is moveable between an inoperative position and an operating position which is situated against the base and aligned with the top windows; a fastener mounted on a belt in order to press the ring-shaped handle against the base; and a sealing element fixed against the peripheral wall of the base and provided with through openings for optic cable, aligned with the respective bottom windows of the base.

FIELD OF THE INVENTION

This invention relates to the field of optic fiber telecommunications and, more specifically, to an aerial splicebox or optic cable end, which includes several new components in order to facilitate the installing and the handling of optic fibers in it, while it provides architecture capable of significantly reducing its external sizes.

HISTORIC BACKGROUND OF THE INVENTION

Fiber optics telecomm systems employing optic cables and electronic equipment are largely used in the telecommunication industry, for the transmission of large volumes of data and voice signals over long distances and practically without noise generation. Splice points and user activation terminal points are required for such systems.

In a splice point, for instance, all the fibers in an end of a given cable are spliced to the fibers corresponding to a new cable extension, in order to continue with the optic cable, necessary to reach one new splice point or a user activation terminal point.

However, in a user activation point, the optic cable fibers, which reach the aerial terminal box, may be fully or partially connected to the drop cables, which are destined to the transport of the optic signal for the end users of the network. The optic cable fibers, which are not connected to a respective drop cables, may pass through the box, unaltered or spliced to a new cable extension, in order to proceed toward a new splice point or user activation point.

In both points, the splice point or the user activation point, the optic fibers are exposed by removing a given length of protection sleeve of the optic cables, in order for them to be properly spliced to the respective multiple cable or drop cables extensions and protected inside of a splicebox or user activation terminal.

The splicebox may be built to serve a given splice point, and it may end up with larger sizes in order to accommodate a larger amount of optic fibers, in the case of splice points with a high number of optic fibers, or be specially designed to operate, in full or partially, such as user activation terminal boxes.

An user activation terminal box, usually simply called a terminal box, usually presents several features which constitute functions to facilitate the activation work of each final user of the optic network covered by the box, since such work is performed in a given number of times which varies in accordance with the clients' requirement, up to a total of 8 or 16, also depending on the configuration of the optic accessories used. Since each activation may require considerable time and enable the occurrence of damage to other connections previously performed in the optic terminal box, it is desirable that the product has an architecture which facilitates the work to be performed and which ensures the safety of the work already done. Many generic and flexible spliceboxes, which it may be used both in splice points and in user activation points, do not allow the effective streamlining and the desirable safety of splice works for extension cables and for drop cables for user activation.

The known boxes present a more worked cable entry structure, in order to ensure a higher level of protection and an simplified fiber organization architecture in a single environment, for a large counting of optic fibers, which affects the safety of the splices already effective at the time of the performance of the connections to the drop cables required due to the demand to be met by a given box with functions at least partially as a terminal box. With the popularization of optic fiber services going to the user house (types of network called FTTx) and the potential for clients signing up for such services, several companies have prepared for a new reality of this market niche, and studies on how to meet the needs of a very large number of clients have shown the need for a drastic reduction of the time spent in each user activation, since the operational difficulties found are too great and to which problematic factors are added, such as lack of labor force trained for the work and shortage of proper equipment for more complex installations. The labor force-related difficulty also dooms cases in which reworks are necessary or routine, hence the fact that it is crucial to maintain the safety of the connections already performed.

Due to the aforementioned factors, it becomes desirable, and even required, to have technical solutions for user activations-clients, which enable a quick, user-friendly and safe installation, capable of reducing the probability of rework and maintenance in a connection previously performed in a box from which drop cables for user activation shall be later derived.

Said factors make impossible the use of more generic models, since they present an internal architecture that is very simple and prone to creating problems in connections performed previously, when the interior of the box is accessed several times, for instance, for a drop cable connection. Generic boxes present, as another limiting factor for their application in user activation points, a level of protection against weather, which is also generic, which many times is redundant in aerial networks and ends up getting in the way o the activation, since it makes it harder to open the box and to use the cable entries in order to favor a more reliable sealing.

For most applications, the size of the terminal boxes must be as small as possible, due to the space available in the telecom networks present in large urban centers and which are normally congested with other optic network and of metallic network products, some active products and other already inactive products which are still allocated in such a way as to take space on the post or in the cordage. The reduced size is also important for special cases in which the space on the post is granted only to products of considerably compact sizes.

From the engineering point of view, a smaller product also presents a smaller cost, which makes it more attractive for the market, which is considerably focused on price due to the high investment which optic network projects still require.

SUMMARY OF THE INVENTION

In view of the aspects discussed above, this invention has the objective of providing an aerial splicebox for optic fiber cables to be installed in post or cordage, presenting, due to the architecture of its components, a substantial reduction in their external size measurements, easier opening, easier closing, and easier entry and accommodation of the optic cables and capable of minimizing the user activation time.

The invention has also the additional objective of providing an aerial splicebox, as defined above and capable of efficiently protecting the splices or connections previously performed in it.

In accordance with the present invention, a splicebox is provided that includes, in a non-electricity conductive material: a base with a peripheral wall provided with a pair of bottom windows and top windows and incorporating an external flange, usually interrupted in the region of the peripheral wall provided with the pair of bottom windows; a cover with a peripheral skirt which incorporates, externally, a surrounding flange; and the hinge connecting the cover to the base in a region opposed to that in which the bottom and top windows are provided, in order to allow the angular movement of the cover from the closed position, with the surrounding and external flanges sitting against each other, and at least an open position in relation to the base.

In order to ensure an airtight closing for the splicebox, to still be provided: a belt with an U-section, to be tightly fit over the flanges, both external and surrounding, when sited against each other, said belt having a first and a second end positioned in opposing sides of the top windows; a ring-shaped handle, having a closed end, hinged in the first end of the belt, and a bipartite opposing end, and the handle being angularly moveable between the inoperative position, away from the top windows, and the operating position sited against the base and aligned with the top windows; and a fastener mounted on one of the parts of belt and of ring-shaped handle, for locking, liberally, the ring-shaped handle against the base.

The tray also includes at least one sealing element provided with at least one through opening aligned with the respective lower window of the base, in order to allow an airtight passing for an optic cable.

The construction proposed by the invention enables a small-sized splicebox to contain a high number of splices of optic fiber cables and of drop cable connection, organized in a practical way, with the splice region and the connection region easily accessible by extremely simple opening and closing operations of the box.

The boxes may also articulate, inside the base, a connector tray provided with connectors disposed in such a way as to considerably simplify the connection operations of the drop cables with the box already installed in a post or in a cordage. It may also be provided, from below the connector tray, a splice tray provided with means to facilitate the accommodation of the optic cables and of its splices or derivations for the connectors for the drop cables.

DETAILED DESCRIPTION OF THE INVENTION

As illustrated in the drawings, the aerial splicebox discussed herein includes a base10and a cover20, both made in non-electricity conductive material, with base10incorporating, in a single piece, a peripheral wall11which is provided with a pair of bottom windows12(seeFIG. 4) for the passing of the respective optic cables CO and of several top windows14opened to the top edge of the peripheral wall11of the base10, and through which they may be easily removed and for the placement of different drop cables CD.

In the illustrated construction, the bottom windows12are formed inside of a housing12aformed externally to the base10and inside of a peripheral lid12bwhich protrudes out from the peripheral wall11of the base10.

The peripheral wall11incorporates the external flange13, usually interrupted in the region of the peripheral wall11provided with the pair of bottom windows12(seeFIG. 6).

The cover20incorporates a peripheral skirt21which also externally incorporates the surrounding flange23and which is connected to the base10, in a region opposed to that of the bottom windows12and top windows14, by a hinge30which enables the cover20to be angularly moved from the closed position, with the surrounding flange23and the external flange13sited against each other, and at least one open position in relation to the base10and in which enables the access to the interior of the box by the of splice and connection operator.

In the illustrated construction, the hinge30of the cover20to the base10is defined in respective confronting portions of the surrounding flange23of the cover20and the external flange13of the base10.

The aerial splicebox discussed herein presents a closing system comprised of four main parts, made of non-electricity conductive material, usually plastic, which are used to make the closing of the box in a very simple and practical, requiring no undesirable effort from the installer and no special tools.

In accordance with the present invention, the closing system includes a belt40, with section transversal shaped like a sideways “U”, to be tightly fit over both the external flange13and the surrounding flange23, when situated against each other, at the time of the closing of the cover20against the base10.

In the configuration illustrated, the base10and the cover20present a substantially rectangular contour, with a belt40presenting a “U” shaped contour involving three edges of the splicebox and having a first end41and a second end42, positioned in opposing sides of the top windows14of the passing of the drop cables CD.

The closing system also includes the ring-shaped handle50, having a closed end51, with hinge at the first end41of the belt40, and a bipartite opposing end52. The ring-shaped handle50may thus be angularly moved between the inoperative position, away from the top windows14, and the operating position sited against the base10and aligned with said top windows14.

In order to provide the locking at the closing of the box, it is also provided a fastener60which it may be mounted on the belt40or on the ring-shaped handle50, for it to be moved between the unlocked position, in which it may be engaged and disengaged in relation to the other from said parts, and the locked position, engaged with said other part and in which it presses the ring-shaped handle50against the base10.

The closing belt may be open in three simple steps, as shown inFIGS. 3A, 3B and 3C. It is also capable of providing extra protection against entry of water when the box is installed in vertical position, usually with the bottom windows12and top14turned downward or even sideways, ensuring sufficient pressing in the sealing rubbers (not illustrated), for the box to be properly sealed in aerial (non-submerse) environments.

The closing system was adapted for a small-sized box, with tilting cover20(cover not fully removable which rotates around a hinge axle fixed in a region of the box opposed to that in which the bottom windows12and top windows14are provided).

Said adaptation includes the division of the ring-shaped handle50in two parts, in the region of its52, in order to allow for the drop cables CD to be easily introduced inside of the ring-shaped handle50, at the time of its installing in the splicebox. The drop cables CD may be inserted in or removed from inside the ring-shaped handle50, through the opening resulting from the bipartition of its opposed end52.

In order for the belt40to not fall off during of box opening and closing operations, a cord45is provided, usually made of synthetic material, which attaches the belt40to the base10, as shown inFIGS. 3A, 3B and 3C.

As illustrated, the fastener60may include an articulated lever61in the region of the second end42of the belt40and which articulates, medially, the end of a locking arm62having a free end62ato be engaged to the bipartite opposed end52of the ring-shaped handle50, in such a way as to press the latter against the said second end42of the belt40when the lever61is moved to the locking position illustrated inFIG. 3C.

As it may be noted, the cover20opens, from above, with the hinge30, making the interior of the box accessible to the operator. For the cover20to remain open without closing accidently and causing any damage to the work being performed, a metal rod25is provided, with round corners and holes26in one of the ends, herein called free end, which may be used for support in a protuberance15of the base10. Only one hole is used at a time, and several holes26enable the cover20to remain open in different angles, a very useful feature, considering that the box must be installed in posts, which may be occupied by other elements which make the opening of the box difficult.

The splicebox discussed herein also includes at least one sealing element70, obtained in polymeric material, usually rubber, with an oblong shape and provided with at least one through opening71for the passing of the respective optic cable CO. In the construction illustrated, see especiallyFIGS. 7 and 8, it is provided a sealing element70(double grommet) in a single piece, with an elongated oblong shape, and presenting a pair of through openings71and is designed to be fitted inside of the housing12aof the base10, having its through openings71aligned with the bottom windows12of the base10, in order to allow for the tight-fit passing of a optic cable CO through each set of through opening71and lower window12. In order to facilitate the adaptation of the sealing element70around the optic cables CO, each one of the through openings71is radially connected to the exterior of the sealing element70by a respective slit72.

In order to ensure a safe airtight sealing in the entry of the pair of optic cables CO inside the base10, it is also provided a pressing element74, preferably constructed in material non-electricity conductive rigid, for instance, a polymer and formed by two symmetrical parts74a,74b, sited and locked, one against the other along the junction line which severs the geometric axle of the two bottom windows12. The two symmetrical parts74a,74bof the pressing element74define, jointly, a format provided with two holes74caligned with the through openings71of the sealing element70and with the bottom windows12of the base10.

Each one of the two symmetrical parts74a,74bof the pressing element74has its region peripheral external sited against the front edge of the peripheral lid12bof the housing12aof the base10. Each one of the two symmetrical parts74a,74b, incorporates, in one of the ends, the perforated ear75, in order to allow the passing of a screw76for the fixation and tightening of the pressing element74against the peripheral wall11of the base10.

Each one of the symmetrical parts74a,74bof the pressing element74incorporates, in the internal side, a shoe77in high relief and placed along the junction line between the two parts, in such a way as to press the sealing element70against the portion of the peripheral wall11of the base10which defines the bottom of the housing12a, enabling that the sealing element70is forced to deform elastically in expansion, and pressed around each one of the optic cables CO, enabling the obtaining of the adequate sealing of this region of entry and exit of optic cables CO. As already mentioned above, the drop cables CD are removed from the splicebox through the top windows14, which, as illustrated in theFIGS. 1 and 6, receive in them the fitting tight of grommets100made of polymeric material, for instance rubber, each one of said grommets100and provided with passing orifices101, associated with top slits (not illustrated), which allow the passing orifices101to be open from the top of the respective grommets100, for the airtight passing of respective drop cables CD. The passing orifices101are open for the top housing AS of the splicebox.

The ring-shaped handle50is configured in order for the top windows14to have their contour contained within the internal contour of the ring-shaped handle50, when it is moved to its operating position.

In the construction that is preferred and illustrated, the holes74cof the pressing element74are formed by respective portions of hole defined, each one, in one of the two symmetrical parts74a,74bof the pressing element74. The holes74cof the pressing element74are disposed according with two alignments separated from each other length-wise of the spliceboxes, while the top windows14are positioned in a higher level and open to the top edge of the peripheral wall11. This distribution enables a more adequate distribution of the optic cables CO, of their splices and of the drop cables CD inside of the splicebox.

In a constructive way, base10articulates in it a connector tray80having its front face80aturned to the cover20and the back face80bturned to the interior of base10. The connector tray80carries several connectors81, each one presenting an terminal entry81a, placed in the back face80b, in order to receive a optic fiber FO derived from the optic cable CO, and an exit terminal81b, placed in the front face80a, in order to receive the fitting of the respective drop cables CD to be derived from the box and sent to a user.

As illustrated, the connectors81are positioned tilted in relation to the connector tray80, with the exit terminals81bturned to the top windows14and to the cover20.

Thus, the invention presents a interchangeable module, defined by the connector tray80, which may be mounted on the base10to enable an installing modality in which optic connectors81are used to the instead of splices to perform the activation of the clients-users. In the constructive form illustrated, the connector tray80articulates a small plate82, carrying, in respective perforated housings, a set of optic connectors81, which are positioned behind and above the same set of optic connectors81. Preferably, both sets of optic connectors81have a maximal capacity of 16 optic adapters of the type SC. As already mentioned, the optic connectors81are placed in tilted position, providing internal space saving and easy access to the operator, which is further facilitated by the possibility of angular motion of the plate82in relation to the connector tray80and to the other set of optic connectors81.

The connector tray80enables the installer realize a activation of each user via a simple opening of the cover20and of a simple fitting, to a respective optic connector81, of drop cables CD, which may be defined by a optic fiber cable non-divided and directed to a specific user.

In these operations of drop cable connection CD to each respective connector81, the installer does not need to access the region of the box defined between a connector tray80and the bottom of the base10, which contains important optic accessories which must not suffer disturbances after its installing and accommodation.

The back face80bof the connector tray80incorporates housings83, for the accommodation and organization of optic fibers FO, limiting the curvature of said optic fibers, and grooves (not illustrated) which enable the fitting of splices or of optic dividers, depending on the features of the installing to be served by the splicebox. The connector tray80works as a kind of cover for the back region, protecting the more fragile content of the splices, divisions and optic connections and defining the surface which shall be visible for the installer responsible for the activation of the end client via the respective drop cables CD which may be defined by a optic fiber.

The splicebox discussed herein80can perform, according with the aforementioned, the accommodation of several components and optic accessories in a structure made of few pieces and in a considerably compact way.

The base10may also articulate in it a splice tray90having a front face90a, turned to the connector tray80and carrying means of accommodation92for the optic fibers FO, and a back face90bturned to the interior of the base10.

The splice tray90enables the accommodation of the splices and the organization of the optic fibers FO within the splicebox. The splice tray90is designed to take the maximal advantage of the technical features of the splicebox, presenting a format which completely fills the available area, maximizing the surface to house the optic fibers FO, at the same time it enables the crossed entry of optic elements in it, enabling the tray to be tilted in relation to the other, without causing steep curvatures in the optic fibers FO.

The splice tray90of said invention, in addition to protecting optic elements which are found under its back face90band must not be accessed after its installing. It also presents a set of rubber pieces94which allow the accommodation of up to 16 splices and a fixation system which enables the connector tray80to be mounted on a splice tray90, without causing an increase in the occupation of space in the other directions. The feature not observed in other splice trays90is the distribution of the hooks for performance of rotation of the trays which, in this case, are provided in the lower side ends. This feature enables a better usage of space, leaving a region central free of impediments for the guiding of the optic fibers. As a result, more optic fibers may be affixed in the region lower of the base10.

In order to perform the management of the internal space occupied by the different cables within the box internal, the drop cables CD and the external optic cables CO are separated in different planes, with the main optic cables CO in the lower plane, in a bottom housing AF defined between the back face90bof the splice tray90and the bottom of the base10and for the interior of which the bottom windows12of the base10are open, and with each one of which the through openings71of the sealing element70are aligned, as well as the holes74cof the pressing element74.

Each optic tube TO, separated from the optic cable CO which enters the splicebox, has its optic fibers FO connected, by respective splices (not illustrated), to the respective optic extensions EO, installed in a intermediary housing AI, defined between the connector tray80and the splice tray90, and provided with a connector end to be coupled to the terminal entry81aof the respective optic connector81.

The drop cables CD may then be placed in a higher plane, complying with the logic of the order of assembly of the box, since the drop cables CD are installed last, so they must be located in a more accessible plane, i.e., in a top housing AS, defined between the front face80aof the connector tray80and the cover20and to the interior from which the passing orifices are open101of the grommets100fitted in the top windows14.

As one can see in the description above and by the drawings, the connector trays80and the splice trays90have their geometric hinge axles placed inside the base10and parallel to the hinge axle of the cover20to the base10.

This spatial organization enables the product to have a reduced width, without compromising the space between the of the drop cable entries, which is an important space, since it separates one cable from the other, reducing as chances of a new activation compromising another activation already performed. This separation between planes and between the drop cables CD may be obtained in several ways.

The splicebox discussed herein may receive, in the external part of its back wall, the adequate ironwork F configured to enable an easy installing in posts or even in cordages.

Despite the fact that only one configuration of the aerial splicebox under examination is illustrated herein, it must be understood that alterations can be made in the form and distribution of the components, without violating the construction concept in the claims which accompany this report.