ES2845211B2 - OPTICAL JUNCTION BOX OR TERMINATION OF AN OPTICAL CABLE IN A FIBER OPTIC NETWORK - Google Patents

Description

DESCRIPTION

OPTICAL JUNCTION BOX OR TERMINATION OF AN OPTICAL CABLE IN A NETWORK

FIBER OPTIC

field of invention

The present invention relates to an optical junction or termination box, of hermetic configuration, of the type having a casing provided with an access opening that is closed by a sealed cover and provided with an input adapter having an external end connected to an optical distribution cable, made up of one or more optical fibers, and an internal end by which a fiber or fiber optic division of the distribution cable is connected to a balanced and/or unbalanced splitter device, the cap is provided with output adapters, each of which has an inner end, connected by means of a splitter device, to a fiber or fiber split of the optical distribution cable, and an outer end adapted to receive a connector of a respective terminal optical cable of a user.

Background

An optical termination box is described in patent application BR 102016029000 7, by the same applicant, with multiple outputs to connect multiple user terminal optical cables to a distribution optical cable that will be received in said optical box.

In this above configuration, the single or each of the multiple optical fibers of the distribution optical cable received in the optical termination box are connected to a respective output adapter mounted on a lid of the box, by means of lengths of the fiber optical fiber of the distribution cable itself or by splitters of at least one optical fiber of the distribution cable that can be, for example, of the "low friction" type.

The previous configuration is designed to receive and retain, without the risk of it coming out, the multi-fiber or “low friction” distribution optical cable (with just one fiber) and also allows connection operations of the cable fiber(s). distribution optic, with outlet adapters on the box cover, performed by the installation operator outside the termination box installation site and before the cover is closed against the box, avoiding the movement of the internal elements that house the fiber optic sections inside the termination box and the movement of the optical components as a consequence of vibrations or impacts.

Despite the constructive and operational advantages achieved with the optical termination box developed by the applicant and described in patent application BR 102016029000-7, the applicant has developed a new configuration solution, which is the subject of patent application BR 102018075693-1 and according to which the optical box can be provided with means that allow it to operate not only as an optical termination box, but also as an optical junction box, capable of receiving a cable or distribution cabling, which contains one or multiple optical fibers, with balanced or unbalanced outputs, or part of multiple optical fibers in the distribution cable, terminated within the box, so that each fiber or fiber split terminated in the box can be connected to a respective cable user terminal, as long as the rest of the divisions of the fiber or the other optical fibers of the distribution cable, do not terminate inside the c aja, exiting through a respective output adapter, to go to another derivation and/or optical termination by means of a cable or continuation wiring.

According to the configuration proposed in the patent application BR 102018075693-1, it is also possible to use the optical termination box, which has the advantageous characteristics described in the previous patent application BR 102016029000-7, as an optical junction box, allowing , if it is desirable and convenient, derive, in each optical box of a network, part of the input optical power, according to the needs of each application and until there are no more fibers to derive or there is not enough power for a new derivation of the optical signal from the last box, which starts to function as an optical termination box.

The optical box object of the application BR 102018075693-1 therefore enjoys the advantageous aspects of application versatility as a junction box and/or termination box to be used in a fiber optic network with connectorized cables, preferably pre-connectorized, allowing the assembly operations of the input adapter, the output adapters and the housing cover to be carried out in the factory so that the optical box is received by the installer, already in the sealed and tested condition, preventing access to its interior during the installation of the box in the fiber optic network, it is enough for the installers to connect the end connectors of the distribution, continuation and termination to their pre-mounted adapters on opposite end regions of the optical box housing.

Despite the advantageous aspects mentioned above, the optical box object of patent application BR 102018075693-1 still has its casing provided with two opposite terminal openings, which are hermetically sealed, one to receive the distribution or continuation cable through one inlet adapter and the other to be closed by the sealed lid that carries the outlet and (if applicable) continuation adapters. This configuration, in addition to requiring the necessary components for the two end closures and fusion welding or adhesive curing times, with the corresponding manufacturing and assembly costs, makes processing and productivity of this solution difficult.

Another aspect to take into account in the boxes that are the subject of patent application BR 102018 075693-1 refers to the fact that the lid is permanently sealed to the casing by fusion or adhesive, which does not allow its subsequent removal from the casing even during the production phase of the optical box. If the test of the box, after the assembly of its internal connections and its final closure, results in a failure, it will no longer be possible to reuse the lid and the casing, which requires reassembling all the internal elements that these two parts carry. which are destroyed.

Description of the invention

In view of the foregoing application limitations and in order to construct a sealed box with opposed ends requiring hermetically mounted adapters, the present invention aims to provide a simple and robust configuration optical box with relatively few components, having a housing Provided with a single access opening to be hermetically sealed by a mechanically sealed and reusable lid, said optical box is further provided with means for its operation not only as an optical termination box, but also as an optical junction box, capable of receiving a distribution cable or cabling, containing one or multiple optical fibres, with balanced or unbalanced outputs, or part of multiple optical fibers of the distribution cable, terminating within the box, such that each terminated fiber or split fiber in the box can be connected to a respective user terminal cable, in both the rest of the divisions of the fiber or the other optical fibers of the distribution cable, do not end inside the box, exiting through a respective output adapter, to go to another derivation and/or optical termination by means of a cable or continuation wiring.

According to the invention, the optical box can be used as an optical derivation box, allowing, if desired and convenient, to derive, in each optical box of a network, part of the input optical power, according to the needs of each application and until there are no more optical fibers to drop or until there is not enough power to drop the optical signal from the last box, which will only function as an optical termination box.

Brief description of the drawings

The invention will now be described by way of example with reference to the attached drawings, in which:

Figure 1 is an enlarged perspective view of an optical box, which functions as a junction box;

Figure 2 represents a bottom plan view of the enlarged assembly illustrated in figure 1 that receives, by means of an input adapter, a distribution optical cable formed, in this example, by a single optical fiber that is divided into optical fibers of end in the optical box, to be connected, each one, with a respective user terminal cable, and a continuation optical fiber, which does not end inside the box, leaving the latter through a respective adapter continuation, to go to another junction and/or optical termination box, by means of a continuation cable or wiring; Figure 3 illustrates a perspective view of the optical box of Figure 1 assembled and in longitudinal section through the center;

Figure 4 illustrates a perspective view of the optical box of Figures 1 and 3, in assembled condition and viewed from the end closed by the cover;

Figure 5 represents a view in longitudinal section through the center of the optical box illustrated in Figure 3;

Figure 5A depicts an enlarged detail of Figure 5 to better illustrate how the end cap is supported, retained and sealed by a retaining ring against the open end of the optical box housing;

Figure 6 represents a front view of the cover of the optical box of Figures 1, 3 and 5; Figure 7 represents a plan view of the internal side of the retaining ring of the cover in the casing of the optical box; Y

Figure 8 is an enlarged perspective view of the assembly defined by the tubular casing, the cover plate and the retaining ring, illustrating the elements for blocking against rotation of the plate at the open end of the tubular casing.

Description of the invention

As illustrated in the attached drawings, the present invention applies to a hermetic CX optical box, of the type having a tubular casing 10, of approximately circular cross-section, without being limited to this configuration, and made of any material suitable for the underground or outdoor installation, for example, polypropylene, which has a closed end 10a and an open end 10b, opposite the first and circular in outline, provided with an external thread 11 to be closed by a cover 20, preferably built on a plate 21 of any suitable polymer, substantially circular in outline and presenting an external face 20a and an internal side 20b that can be supported and fixed against the open end 10b of the tubular casing 10.

The plate 21 incorporates, on the internal side 20b of the cover 20, a tubular projection 22, with a circular contour and with an external diameter dimensioned to allow its telescopic adjustment inside the open end 10b of the casing 10.

The plate 21 presents a peripheral region 23, radially external to the tubular projection 22 and which incorporates, on the internal side 20b of the cover 20, a circumferential rib 23a that bears against the open end 10b of the casing 10, when closing the cover 20 in housing 10

As illustrated in figure 8, the peripheral region 23 of the plate 21 is provided with at least one locking element 24, configured to engage a respective locking element 14 provided in the open end 10b of the tubular casing 10. , allowing plate 21 to lock against rotation against tubular casing 10 when abutting, and advanced, against open end 10b of tubular casing 10.

In the illustrated configuration, the blocking element 24 is in the form of an axial projection 24a, of reduced width, incorporated in the circumferential rib 23a of the peripheral region 23 of the plate 21, the blocking element 14 being defined by a respective axial cutout 14a provided at the open end 10b of the tubular casing 10, to receive the axial projection 24a of the plate 21, locking the latter against rotation in an advanced position when abutting against the open end 10b of the tubular casing 10.

The tubular projection 22 carries, externally, at least one elastomeric sealing ring 30, which is radially compressed against the inside of the open end 10b of the casing 10, guaranteeing the tightness of the lid 20-casing 10 connection.

The fixing of the cover 20 in the casing 10 is achieved by means of a retaining ring 50 provided with an internal thread 51 that engages with the external thread 11 of the open end 10b of the casing 10 and incorporating, radially and internally, a radial flange external face 52 that is axially supported against plate 21, on the external face 20a of the cover 20.

Thus, when retaining ring 50 rotates in the tightening direction, with its internal thread 51 engaged with external thread 11 of housing 10, outer radial flange 52 of retaining ring 50 pushes plate 21 against the casing 10, causing the telescopic anchoring of the tubular projection 22 inside the open end 10b of the casing 10, as best illustrated in figures 5 and 5a and also the engagement of the axial projection 24a in the axial cutout 14a of the open end 10b of the tubular casing 10, locking the plate 21 in the tubular casing 10 against rotation.

Retaining ring 50 has at least one locking element 55 which mates with a locking element 25 provided on cover 20, locking retaining ring 50 against rotation on plate 21 and consequently on housing 10, when the cover 20 is fully pressed against the casing 10 the retaining ring 50 is screwed onto the outer end 10b of the tubular casing 10.

In the configuration illustrated in figures 6 and 7, multiple locking elements 25 are provided that take the form of a circular alignment of projections 25a incorporated in the plate 21, on an external face 20a of the cover 20, while the respective locking elements 55 take the form of a similar alignment of cutouts 55a provided with the external radial flange 52 of the retaining ring 50, on its face opposite to the cover 20, the cutouts 55a are dimensioned to each receive a respective projection 25a of plate 21 upon completion of tightening of retaining ring 50. With this configuration, when installing projections 25 of plate 21 into cutouts 45 of retaining ring 50, with axial projection 24a of plate 21 already inserted into the respective axial cutout 14a of the tubular housing 10, the retaining ring 50 can no longer be freely rotated towards the engagement release of its internal thread 51 with respect to the external thread 11 of the housing 10.

Although the retaining ring 50 functions as a tamper-evident seal for the CX optical case, it is constructed with at least one weakened radial region 56 (Figures 4 and 7), to allow it to be broken in this region, to open the already finished optical box, if any fault or irregularity is detected in its manufacture and assembly. In this way, the casing 10, the cover 20 and the internal elements already installed inside the casing can be used.

As mentioned, the illustrated optical box CX is constructed to function simultaneously as a junction box and a termination box, with its plate 21 provided with one input hole FE, a plurality of output holes FS, one output hole continuation FC and a pressurization port OP, whose functions will be described below.

The entry port FE is sealed in an entry adapter AE having an external end to which an entry connector CE can be coupled, preferably by pre-connectorization, to the end of an optical distribution cable CD that can consist of a single optical fiber or multiple optical fibers.

At an internal end of the input adapter AE, a link connector CL is coupled, preferably through pre-connectorization, of at least one optical fiber section EFO that can be represented by a single optical fiber section of a communication cable. "single-fiber" CD distribution, as illustrated, or a section of one of the optical fibers of a "multi-fiber" CD distribution cable, said CD distribution cable provides a predetermined optical power.

The section of optical fiber EFO is led, inside the tubular casing 10, to a respective input splitter device DE, where it is divided into a continuity fiber FC and a termination optical fiber FT, with unbalanced optical powers, being the terminating optical fiber FT conducted, with or without fusion splicing EF of intermediate cabling, to an output splitter device DS, where it is divided into multiple user optical fibers FU, each of which is selectively connectable, preferably by connectorization by pre-connectorization, to the respective connectors C, at the ends of the respective outlet adapters AS, mounted, in a sealed manner, in the respective outlet holes FS provided in the plate 21 of the cover 20, as illustrated schematically in Figure 2. At the outer ends of the output adapters AS, the connectors C are connected, generally by pre-connectorization, at the ends of the respective user terminal cables CT. The user optical fibers FU may have equal or unbalanced optical powers, to provide different user connection points with different optical power demands. Meanwhile, the FT termination optical fiber generally features lower optical power than that of the FC continuation optical fiber and scales according to the needs of the users to be met and the topology of the optical fiber network.

The number of input splitter devices DE and output DS can vary depending on the construction characteristics of the distribution cable CD and also the number of adapters AS that will be arranged through the cover 20 of the optical box CX.

As schematically illustrated in Figure 2, the fiber optic continuation FC, freed from the input splitter device DE, is preferably pre-terminated with a connector C which is mated to a continuation adapter AC provided in a continuation hole. FC continuation of plate 21 of cover 20. At one external end of the AC continuation adapter, a C connector is connected, generally by pre-connectorization, to the end of a CC continuation cable to go to a CX optical branch box or of the next termination in the network or bus of optical boxes.

In the configuration example, the input adapter AE and the output adapters AS of the optical junction and termination boxes, and the continuation adapter AC of the optical junction boxes, present any suitable configuration, passing, in a sealed way, through the respective through hole of the plate 21 of the cover 20. Thus, when the retaining ring 40 is completely screwed into the open end 10b of the casing 10, the latter is completely sealed by the cover 20, which can no longer be removed of the tubular casing 10, except for the rupture of the weakened radial region 46 of the retaining ring 40.

The tubular casing 10 is designed to operate in a totally sealed manner upon mounting of the cover 20 against the open end 10b of the casing 10, with the cover 20 carried the input adapter AE, the output adapters AS and the continuation adapter AC, the latter being generally provided only in optical junction boxes.

Once the installation of the CX optical box is complete, with the cover 20 already sealed against the tubular casing 10, the CX optical box, now hermetically closed, can be pressurized with a suitable gas that is introduced into it by means of a check valve. pressurization mounted through a respective pressurization hole OP provided in the plate 21 of the cover 20, as illustrated in figures 1, 5 and 6.

The present optical box is of the type that further comprises a tray 40, made of an electrically non-conductive material, for housing EFO optical fiber, FT termination optical fibers, FU user optical fibers, FC continuation optical fiber and the input divider devices DE and output DS inside the optical box CX, the tray 40 being housed inside the tubular casing 10 when the latter is fixed to the cover 20. The tray 40 has a first end 41, to bear internally against the closed end 10a of the tubular casing 10, and a second end 42 mounted on the internal side 20b of the cap 20, so as to be displaced when sealing the cap 20 on the open end 10b of the tubular casing 10.

As mentioned, when the optical box CX is used as an optical termination box, the plate 21 of the cover 20 can be built with only "n+1" through holes, the holes being "n" output holes FS, each one of which receives and retains a respective output adapter AS for each user terminal optical cable CT and an input port FE for receiving and retaining the input adapter AE. In this case, it is not necessary for the cover 20 to have the continuation hole FC.

However, for CX optical boxes with bypass function, plate 21 of cover 20 has "n+2" holes, to mount "n" output adapters AS, of the input adapter AE and of an AC continuation adapter into a respective continuation hole FC, while an optical continuation cable CC is attached to the outer end of the continuation adapter AC.

It should be understood that the number "n" of output adapters AS in the cover 20 may vary depending on the configuration of the output splitter devices DS and in addition to the network topology in which the CX optical boxes will be installed and the dimensional limitations of the cover 20 of said CX optical boxes.

Although an embodiment of the invention has been described, it should be understood that modifications may be made in terms of the shape and arrangement of the different component parts of the optical box, involved in the branching and termination of the optical fibers of an optical cable. distribution, all within the scope defined by the claims attached to the present specification.

Claims (10)

1. Optical branch or termination box for an optical cable in a fiber optic network, comprising a tubular casing (10), which has a closed end (10a) and an open end (10b) against which it rests and fixes tightly seals a lid (20), characterized in that the open end (10b) of the tubular casing (10) is provided with an external thread (11) and a locking element (14), the lid (20) being provided with a first locking element (25) and a second locking element (24) that engages with the locking element (14) of the tubular casing (10), locking the cover (20) against rotation against the open end (10b ) of the tubular casing (10), which has a retaining ring (50) with an internal thread (51), which engages with the external thread (11) of the casing (10), and at least one element of lock (55) that is coupled to the first locking element (25) of the cover (20), locking the retaining ring (50) with respect to the cover (20) and the face against rotation. house (10), when pressed, by means of the retaining ring (50), the cover (20) against the open end (10b) of the casing (10); the cover (20) being traversed, in a sealed manner, by an input adapter (AE), which can be coupled from the outside of the casing (10), an input connector (CE) of an optical distribution cable (CD) with one or more optical fibers, and by output adapters (AS), each of which can be coupled to a connector (C) provided on a respective user terminal (CT) cable. 2. Optical box, according to claim 1, characterized in that the cover (20) incorporates a tubular projection (22) that is telescopically mounted inside the open end (10b) of the casing (10), having at least a sealing ring (30) radially compressed between the tubular projection (22) and the interior of the open end (10b) of the casing (10). 3. Optical box, according to any of claims 1 or 2, comprising an optical fiber housing tray (40) mounted on an internal side (20b) of the cover (20) and supported internally against the closed end ( 10a) of the tubular casing (10), characterized in that the input adapter (AE) is coupled inside the tubular casing (10) to a link connector (CL) of at least one section of optical fiber (EFO), while the tray (40) houses an output splitter device (DS) in which a terminating optical fiber (FT) is divided, in a balanced or unbalanced way, into user optical fibers (FU), each of which it receives a connector (C) coupled to a respective output adapter (AS), inside the tubular casing (10). 4. Optical box, according to claim 3, characterized in that, in a branch optical box (CX), the tray (40) also houses an input splitter device (DE) in which a section of optical fiber is divided. (EFO), unbalanced, in a continuation optical fiber (FC) and a terminating optical fiber (FT), while the cover (20) is traversed, in a sealed manner, by a continuation adapter (AC) that receives, inside the tubular casing (10), a continuation fiber optic connector (C) (FC) and, outside the tubular casing (10), a connector (C) provided at the end of a respective cable of continuation (CC) that goes to a next optical box (CX) of derivation or termination. 5. Optical box, according to any of the preceding claims, characterized in that the cover (20) is defined by a plate (21) that incorporates a tubular projection (22) and is provided with: outlet holes (FS) for mounting output adapters (AS); an entry hole (FE) for mounting the entry adapter (AE); and a continuation hole (FC) to mount the continuation adapter (AC) of a branch optical box (CX), while the retaining ring (50) incorporates, internally, an external radial tab (52) that rests axially against the plate (21), on the external face (20a) of the cover (20), pressing the latter against the open end (10b) of the tubular casing (10) and generating the telescopic coupling of the tubular projection ( 22) inside the open end (10b) of the casing (10), by screwing the internal thread (51) of the retaining ring (50) into the external thread (11) of the tubular casing (10). 6. Optical box, according to claim 5, characterized in that multiple first blocking elements (25) are provided that take the form of a circular alignment of projections (25a) incorporated into the plate (21), on an external face (20a). of the lid (20), while the respective locking elements (55) take the form of an equal alignment of cutouts (55a) provided in the outer radial flange (52) of the retaining ring (50), on its oriented face towards the cover (20), each cutout (55a) is dimensioned to receive a respective projection (25a) of the plate (21) upon completion of the tightening of the retaining ring (50). 7. Optical box, according to any of claims 5 or 6, characterized in that the plate (21) of the cover (20) also has a pressurization orifice (OP) to mount a valve (V) for pressurization of the tubular casing (10), by closing its open end (10b) with the cover (20). 8. Optical box, according to any of claims 5 to 7, characterized in that the plate (21) presents a peripheral region (23), radially external to the tubular projection (22) and that incorporates, on the internal side (20b ) of the cover (20), a circumferential rib (23a) that bears against the open end (10b) of the casing (10), when closing the cover (20) on the casing (10). 9. Optical box, according to claim 8, characterized in that the second locking element (24) is in the form of an axial projection (24a) incorporated into the circumferential rib (23a) of the peripheral region (23) of the plate (21). ), the blocking element (14) being defined by a respective axial cutout (14a) provided in the open end (10b) of the tubular casing (10), to receive the axial projection (24a) of the plate (21). Optical box, according to any of claims 1 to 9, characterized in that the retaining ring (50) has at least one weakened radial region (56) to break the retaining ring (50).