Patent Description:
A FTTH ("Fiber To The Home") network is an optical access network providing a number of end customers with broadband communication services from operators, i.e. with services requiring data transmission at a very high rate, for example of some Mbit/s.

Typically, a FTTH network comprises multiple junction or distribution boxes or cabinets which cooperate with an access network and which may be installed in or near the basement of the building where end users reside, in an underground pit, on a wall, or on a pole. Optical cables exiting the junction or distribution boxes can be routed directly to the customer or to further junction or distribution boxes, for example arranged at different floors of the building.

An installed optical junction or distribution box may be opened for example for maintenance issues or for changing some fiber connections therein. During such operations there is a significant risk of fiber damage, especially in case of multiple intersecting fibers incoming the box from many optical ports.

<CIT> discloses a fiber organizer for insertion into an optical junction or distribution box. The organizer has a planar base with a spool structure for storage of fibers. Moreover, superimposed splice trays are hinged to a tray holding section formed integrally with the base. Fiber ramps of the tray holding section are shaped to route optical fibers to the different trays along respective fiber channels. Accordingly, the fibers in the splice trays are accessible individually without disturbing the other fibers. However, incoming and outgoing fibers in the areas out of the splice trays are still arranged with intersecting paths.

<CIT> discloses a fiber management system where the fibers are arranged on two different floors and in splice trays mounted to the higher floor. Most of the lower floor can be accessed only by rotating away the whole higher floor, with all the splice trays lying thereon. This operation is cumbersome and may cause high mechanical stress to the fibers.

<CIT>, <CIT>, <CIT> show other known examples of fiber management systems where the fibers are arranged on floors at different heights and are routed between the floors through inclined ramps.

The Applicant has tackled the problem of reducing fiber intersections within an optical junction or distribution box, whereby fiber routing inside the box can be modified with a reduced risk of fiber damage.

The Applicant has found a fiber routing insert for an optical junction or distribution box having a first floor, a raised second floor and an inclined channel joining the first floor and the second floor. Optical fibers, for example entering the box from a derivation cable, may be guided along a first path on the first floor. Then, the fibers may be guided along an inclined path defined by the channel, without crossing with other fiber sections within the first path. Thereafter, the fibers are guided along a second path on the second floor and may exit the box and be fed to drop cables without returning to the first floor. Splice trays are rotatably connected to the second floor. The first floor can be accessed by just rotating up the splice trays, thereby leaving clear a tray opening formed in the second floor. There is no need instead to rotate the whole second floor.

Therefore, one aspect of the present invention relates to a fiber routing insert for an optical junction or distribution box, comprising a first floor and a second floor, the second floor being arranged at a raised position relative to the first floor. The insert further comprises first guide elements formed on the first floor, the first guide elements defining a first path configured to receive optical fibers, and second guide elements formed on the second floor, the second guide elements defining a second path configured to receive optical fibers. A channel is inclined to, and joins, the first floor and the second floor, the channel defining an inclined path configured to receive and guide optical fibers between the first path and the second path. The insert comprises one or more splice trays, each splice tray comprising two fiber access openings and third guide elements defining a third path configured to receive and guide optical fibers between said fiber access openings. The second floor has a tray opening for accessing to the first floor, at least one splice tray being rotatably connected to the second floor for engaging and clearing the tray opening.

Preferably, a gap is formed between the first floor and the channel, and the first path has a crossing portion extending through the gap.

Preferably, the channel has a first end portion connected to the first floor, a second end portion connected to the second floor, and a bridge portion between the first end portion and the second end portion, wherein the gap is formed between the first floor and the bridge portion.

Preferably, the first guide elements are shaped at the crossing portion to guide optical fibers along a crossing direction, and the channel is configured to guide optical fibers transversally to the crossing direction.

Preferably, the channel comprises a channel floor having two channel side edges, and channel walls arranged along the channel side edges for retaining optical fibers within the inclined path.

Preferably, a plurality of splice trays are arranged at a plurality of tray levels, a ramp element is partitioned in a plurality of tray connecting paths configured to receive distinct optical fibers, and the tray connecting paths extends between a common collecting portion of the first path or the second path and distinct fiber access openings at distinct tray levels.

Preferably, the second path extends at least partially around the tray opening.

Preferably, each splice tray is rotatable relative to the second floor between a lowered position proximate to the first floor and a raised position distal from the first floor.

Preferably, said at least one splice tray engages the tray opening in the lowered position and clears the tray opening in the raised position.

Preferably, said at least one splice tray is flush with the second floor in the lowered position.

Preferably, the first guide elements comprise first guide walls projecting from the first floor and arranged along the first path, and the second guide elements comprise second guide walls projecting from the second floor and arranged along the second path.

Preferably, the first floor and second floor are formed integrally in one piece.

Under another aspect, the invention relates to an optical junction or distribution box, comprising a first floor and a second floor arranged at a raised position relative to the first floor, and side walls surrounding the first floor and the second floor. First guide elements are formed on the first floor, the first guide elements defining a first path configured to receive optical fibers, and second guide elements are formed on the second floor, the second guide elements defining a second path configured to receive optical fibers. One or more first optical ports are formed in the side walls, each first optical port providing a fiber access to the first path, and one or more second optical ports are formed in the side walls, each second optical port providing a fiber access to the second path. A channel is inclined to, and joins, the first floor and the second floor, the channel defining an inclined path configured to receive and guide optical fibers between the first path and the second path. The insert comprises one or more splice trays, each splice tray comprising two fiber access openings and third guide elements defining a third path configured to receive and guide optical fibers between said fiber access openings. The second floor has a tray opening for accessing to the first floor, at least one splice tray being rotatably connected to the second floor for engaging and clearing the tray opening.

The present invention will now be described in more detail hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown.

<FIG> and <FIG> shows an optical junction or distribution box <NUM> and a fiber routing insert <NUM> within the optical junction or distribution box <NUM>. In <FIG>, the fiber routing insert <NUM> is isolated from the optical junction or distribution box <NUM>.

The insert <NUM> comprises a first floor <NUM> and a second floor <NUM>. The first floor <NUM> and the second floor <NUM> are fixed together, and in the preferred embodiment they are integrally formed in one piece. Such piece, as well as the whole insert <NUM>, is preferably made of a plastic or metallic material.

The second floor <NUM> is arranged at a raised position relative to the first floor <NUM>. In detail, the first floor <NUM> and the second floor <NUM> are spaced apart along a first direction X-X. Preferably, the first floor <NUM> and the second floor <NUM> are substantially planar and are arranged perpendicular to the first direction X-X. The first floor <NUM> is contoured by a first floor edge, and the second floor <NUM> is contoured by a second floor edge.

Moreover, the insert <NUM> and/or the optical junction or distribution box <NUM> as a whole can be symmetric about a central plane, which is substantially perpendicular to the first floor <NUM> and second floor <NUM>, i.e. parallel to the first direction X-X.

Accordingly, a first routing volume <NUM> is defined between the first floor <NUM> and the second floor <NUM>. Moreover, a second routing volume <NUM> is defined above the second floor <NUM>, i.e. adjacent to the second floor <NUM> and opposite to the first routing volume <NUM> with respect to the second floor <NUM>. In other words, the second floor <NUM> is arranged between the first routing volume <NUM> and the second routing volume <NUM>.

The optical junction or distribution box <NUM> comprises a base <NUM>, side walls <NUM> surrounding the base <NUM>, and a cover <NUM>. The base <NUM> and the side walls <NUM> define an open compartment <NUM>. Fastening elements <NUM> are configured to removably fasten the cover <NUM> on top of the side walls <NUM>, i.e. opposite to the base <NUM>, for closing the compartment <NUM>.

In the embodiment of the figures, the fiber routing insert <NUM> is housed in the compartment <NUM>, with the first floor <NUM> laying on the base <NUM>, and the side walls <NUM> surrounding the first floor <NUM> and the second floor <NUM>. When the cover <NUM> is fastened on top of the side walls <NUM>, the second routing volume <NUM> is arranged between the second floor <NUM> and the cover <NUM>.

However, in further embodiments which are not shown in the figures, the first floor <NUM> and the second floor <NUM> can be formed integrally with the base <NUM> and the side walls <NUM>. Specifically, the first floor <NUM> may define the base <NUM> of the junction or distribution box <NUM>. In such embodiments, a fiber routing insert <NUM> as described herewith is not required, but the same components as described for the insert <NUM> shall be present in the junction or distribution box <NUM>.

Therefore, for simplicity the invention will be described in the following referring mainly to the fiber routing insert <NUM>. However, the features of the fiber routing insert <NUM> shall be intended as applicable also to a junction or distribution box <NUM> as a whole.

The optical junction or distribution box <NUM> comprises one or more first optical ports <NUM> and one or more second optical ports <NUM> formed in the side walls <NUM>. Each first optical port <NUM> is arranged to provide an optical fiber access to the first routing volume <NUM>, and similarly each second optical ports <NUM> is arranged to provide an optical fiber access to the second routing volume <NUM>.

In detail, each first optical port <NUM> is arranged, referring to the first direction X-X, between the first floor <NUM> and the second floor <NUM>. Moreover, the second floor <NUM> is arranged, referring to the first direction X-X, between the one or more first optical port <NUM> and the one or more second optical ports <NUM>.

In the preferred embodiment, two arrays of first optical ports <NUM> are formed in opposite side walls <NUM> and are spaced apart in a second direction Y-Y perpendicular to the first direction X-X. Similarly, two arrays of second optical ports <NUM> are formed in opposite side walls <NUM> and are spaced apart in the second direction Y-Y. It shall be noted that the central plane, related to the symmetry of the insert <NUM> and the box <NUM>, is perpendicular to the second direction Y-Y.

Each first optical port <NUM> and each second optical port <NUM> is configured for receiving an optical connector <NUM>, such as an optical cable gland.

The fiber routing insert <NUM> comprises first guide elements <NUM> formed on the first floor <NUM> and second guide elements <NUM> formed on the second floor <NUM>. The first guide elements <NUM> are arranged within the first routing volume <NUM>, and the second guide elements <NUM> are arranged within the second routing volume <NUM>. Some of the first guide elements <NUM> may extend, referring to the first direction X-X, from the first floor <NUM> to the second floor <NUM>.

In the preferred embodiment the first guide elements <NUM> comprise first guide walls projecting from the first floor <NUM> in the first direction X-X, toward the second floor <NUM>, and the second guide elements <NUM> comprise second guide walls projecting from the second floor <NUM> in the first direction X-X, away from the first floor <NUM>.

The first guide elements <NUM> define a first path <NUM> configured to receive optical fibers <NUM>, in detail a first fiber portion <NUM> of the optical fibers <NUM>. In fact, the first guide elements <NUM> are arranged along the first path <NUM> and are shaped to guide the optical fibers <NUM> along the first path <NUM>. Accordingly, the first path <NUM> extends on top of the first floor <NUM>, i.e. within the first routing volume <NUM>.

The first guide elements <NUM> may also define more than one first paths <NUM>, for example two first paths <NUM> symmetric to each other. Moreover, each first path <NUM> can be branched, for enabling different arrangements of the optical fibers <NUM> or for spreading and recollecting different optical fibers <NUM> within the first routing volume <NUM>. In any case, only one first path <NUM> will be described, with reference to all the first paths <NUM>.

The first path <NUM> has a first path external end and a first path internal end. The first path external end is arranged adjacent to the first floor edge and/or to the side walls <NUM>.

Moreover, the first path <NUM> comprises a first fiber access area <NUM> at the first path external end. The first guide elements <NUM> are shaped at the first fiber access area <NUM> to guide away from the first floor <NUM>, i.e. out of the first routing volume <NUM>, the optical fibers <NUM> within the first path <NUM>.

Each first optical port <NUM> provides a fiber access to the first path <NUM> at the first fiber access area <NUM>. Accordingly, the one or more first optical ports <NUM> are arranged adjacent the first fiber access area <NUM>.

Preferably, the first path <NUM> further comprises a first fiber coil area <NUM>. The first guide elements <NUM> comprise first fiber coil support members at the first fiber coil area <NUM>. The first fiber coil support members are shaped to guide the optical fibers <NUM> along one or more loops.

The first fiber portion <NUM> of the optical fibers <NUM> extends from the first path external end, where the optical fibers <NUM> may be connected to optical connectors <NUM> at the first optical ports <NUM>, to the first path internal end, by passing through the first fiber access area <NUM> and optionally through the first fiber coil area <NUM>.

The second guide elements <NUM> define a second path <NUM> configured to receive optical fibers <NUM>, in detail a second fiber portion <NUM> of the optical fibers <NUM>. In fact, the second guide elements <NUM> are arranged along the second path <NUM> and are shaped to guide the optical fibers <NUM> along the second path <NUM>. Accordingly, the second path <NUM> extends on top of the second floor <NUM>, i.e. within the second routing volume <NUM>.

The second guide elements <NUM> may also define more than one second paths <NUM>, for example two second paths <NUM> symmetric to each other. Moreover, each second path <NUM> can be branched, for enabling different arrangements of the optical fibers <NUM> or for spreading and recollecting different optical fibers <NUM> within the second routing volume <NUM>. In any case, only one second path <NUM> will be described, with reference to all the second paths <NUM>.

The second path <NUM> has a second path external end and a second path internal end. The second path external end is arranged adjacent the second floor edge and/or the side walls <NUM>.

Moreover, the second path <NUM> comprises a second fiber access area <NUM> at the second path external end. The second guide elements <NUM> are shaped at the second fiber access area <NUM> to guide away from the second floor <NUM>, i.e. out of the second routing volume <NUM>, the optical fibers <NUM> within the second path <NUM>.

Each second optical port <NUM> provides a fiber access to the second path <NUM> at the second fiber access area <NUM>. Accordingly, the one or more second optical ports <NUM> are arranged adjacent the second fiber access area <NUM>.

The second fiber portion <NUM> of the optical fibers <NUM> extends from the second path external end, where the optical fibers <NUM> may be connected to optical connectors <NUM> at the second optical ports <NUM>, to the second path internal end, preferably by passing through the second fiber access area <NUM>. Further fiber passages along further paths may be provided between the second path external end and the second path internal end, as described in more detail below.

According to an aspect of the invention, a channel <NUM> joins the first floor <NUM> and the second floor <NUM>. Preferably, the first floor <NUM> and the second floor <NUM> are joined fixedly by the channel <NUM>. More preferably, the channel <NUM> is formed integrally in one piece with the first floor <NUM> and the second floor <NUM>.

The channel <NUM> extends, referring to the first direction X-X, through the first routing volume <NUM>. In more detail, the channel <NUM> is inclined to the first floor <NUM> and the second floor <NUM> and is also inclined to the first direction X-X.

The optical routing insert <NUM> and/or the optical junction or distribution box <NUM> may comprise more than one channel <NUM>. For example, the figures show two channels <NUM> symmetric to each other. However, only one channel <NUM> will be described in the following with reference to each channel <NUM>.

The channel <NUM> has a first end portion <NUM> connected to the first floor <NUM>, a second end portion <NUM> connected to the second floor <NUM>, and a bridge portion <NUM> between the first end portion <NUM> and the second end portion <NUM>.

A gap <NUM> is formed between the channel <NUM>, in particular the bridge portion <NUM>, and the first floor <NUM>. In fact, the bridge portion <NUM> is raised relative to the first floor <NUM>. The gap <NUM> has a cross section which increases, as measured in the first direction X-X, from the first end portion <NUM> to the second end portion <NUM> of the channel <NUM>.

The channel <NUM> defines an inclined path <NUM> configured to receive optical fibers <NUM>, and in particular an inclined fiber portion <NUM> of the optical fibers <NUM>. In fact, the channel <NUM> comprises a channel floor <NUM> for supporting optical fibers <NUM>. The channel floor <NUM> has two channel side edges extending each from the first end portion <NUM> to the second end portion <NUM>. Moreover, the channel <NUM> comprises channel walls <NUM> for retaining the optical fibers <NUM> within the inclined path <NUM>. The channel walls <NUM> are arranged along the channel side edges and protrude from the channel floor <NUM> in the first direction X-X.

The inclined path <NUM> is configured to guide the optical fibers <NUM> between the first path <NUM> and the second path <NUM>. In detail, the first end portion <NUM> of the channel <NUM> is arranged at the first path internal end, and the second end portion <NUM> of the channel <NUM> is arranged at the second path internal end.

Therefore, one and the same optical fiber <NUM>, or distinct fibers connected in series, may be guided between a first optical port <NUM> and a second optical port <NUM> along the series of the first path <NUM>, the inclined path <NUM> and the second path <NUM>. Correspondingly, the first fiber portion <NUM>, the inclined fiber portion <NUM> and the second fiber portion <NUM> can be identified sequentially. Further portions of the optical fibers <NUM> may optionally be identified along other paths within the optical junction or distribution box <NUM>, as commented in a following part of the description.

Thanks to the channel <NUM>, the first fiber access area <NUM> and the second fiber access area <NUM> can be arranged at different floors, and therefore some fiber intersections can be avoided.

In the preferred embodiment, the first path <NUM> has a crossing portion <NUM> extending through the gap <NUM> which is formed between the first floor <NUM> and the channel <NUM>. Therefore, the channel <NUM> overpasses the first path <NUM> at the crossing portion <NUM>, or in other words the channel <NUM> defines a flyover with respect to the crossing portion <NUM>. Moreover, the first path <NUM> and the channel <NUM> crosses with grade separation. Accordingly, unnecessary fiber intersections are avoided.

It should be noted that the first guide elements <NUM> are shaped at the crossing portion <NUM> to guide the optical fibers <NUM> along a crossing direction A-A. Instead, the channel <NUM> is configured to guide the optical fibers <NUM> (at least within a section of the bridge portion <NUM> above the crossing portion <NUM>) along a channel direction B-B which is transversal to the crossing direction A-A.

In the preferred embodiment, the insert <NUM> and/or the optical junction or distribution box <NUM> comprises one or more splice trays <NUM>. Each splice tray <NUM> is rotatably connected to the first floor <NUM> and/or to the second floor <NUM>, preferably to the second floor <NUM>. In more detail, a tray support member <NUM> is formed on the second floor <NUM>. Moreover, each splice tray <NUM> comprises a connecting member <NUM> for connection to the tray support member <NUM>. The tray support member <NUM> project from the second floor in the first direction X-X away from the first floor <NUM>.

The second floor <NUM> has a tray opening <NUM> for accessing along the first direction X-X to the first floor <NUM> and to the first routing volume <NUM>. The second path <NUM> extends at least partially around the tray opening <NUM>. In the embodiment of the figures, the tray opening <NUM> is spaced from the first fiber coil area <NUM> in the first direction X-X.

Preferably, each splice tray <NUM> is rotatable relative to the second floor <NUM> between a lowered position proximate to the first floor <NUM> and a raised position distal from the first floor <NUM>. At least one splice tray <NUM> may engage the tray opening <NUM> in the lowered position and clear the tray opening <NUM> in the raised position. Accordingly, in the lowered position such splice tray <NUM> can be flush with the second floor <NUM>. In the preferred embodiment a plurality of splice trays <NUM> are arranged, in the lowered position, at a plurality of tray levels which are spaced apart in the first direction X-X.

In detail, each splice tray <NUM> is rotatable around a tray axis extending in the second direction Y-Y. The tray axis preferably extends through the connecting member <NUM> of the tray <NUM>.

Each splice tray <NUM> comprises a tray floor <NUM> contoured by tray side walls <NUM> surrounding a tray routing volume <NUM>. The splice tray <NUM> further comprises third guide elements <NUM> formed on the tray floor <NUM>. The third guide elements <NUM> are arranged within the tray routing volume <NUM>. Moreover, the third guide elements <NUM> comprise third guide walls projecting from the tray floor <NUM> in the first direction X-X, when the splice tray <NUM> is in the lowered position.

The third guide elements <NUM> define one or more third paths <NUM> (optionally symmetric and/or branched) configured to receive optical fibers <NUM>, in detail a third fiber portion <NUM> of the optical fibers <NUM>. Referring to one splice tray and one third path <NUM>, the third guide elements <NUM> are arranged along the third path <NUM> and are shaped to guide the optical fibers <NUM> along the third path <NUM>. Accordingly, the third path <NUM> extends on top of the tray floor <NUM>, i.e. within the third routing volume <NUM>.

Each splice tray <NUM> further comprises two fiber access openings <NUM> formed in the side walls <NUM>. The fiber access openings <NUM> are arranged to provide optical fiber accesses to the third routing volume <NUM>, and in particular to the third path <NUM>. In fact, the third path <NUM> is configured to guide the optical fibers <NUM> between the fiber access openings <NUM>. Preferably, the tray axis extends through the fiber access openings <NUM>. Thus, fiber stress is minimized during tray rotations.

The third path <NUM> extends between two third path ends at the fiber access openings <NUM>. Preferably, the third path <NUM> further comprises a tray fiber coil area <NUM>. The third guide elements <NUM> comprise tray fiber coil support members at the tray fiber coil area <NUM>. The tray fiber coil support members are shaped to guide the optical fibers <NUM> along one or more loops.

Preferably, the splice tray <NUM> further comprises a splice support structure <NUM> within the third path <NUM> for supporting one or more fiber splices (not shown).

The third fiber portion <NUM> of the optical fibers <NUM> extends between the third path ends, where the optical fibers <NUM> may access the third routing volume <NUM> through the fiber access openings <NUM>, preferably by passing through the tray fiber coil area <NUM> and/or through the splice support structure <NUM>. It shall be noted that the third fiber portion <NUM> can be considered as a unitary fiber portion or as the union of two end fiber portions of distinct optical fibers <NUM> which are connected together by a fiber splice at the splice support structure <NUM>.

Preferably, the insert <NUM> and/or the optical junction or distribution box <NUM> comprises a ramp element <NUM> formed on the first floor <NUM> or on the second floor <NUM>, preferably on the second floor <NUM>. The ramp element <NUM> has a top surface inclined to the first floor <NUM>, to the second floor <NUM> and to the first direction X-X. Moreover, the ramp element <NUM> projects in the first direction X-X from the second floor <NUM>.

In the embodiment of the figures, two (symmetric) ramp elements <NUM> are provided. The ramp elements <NUM> are spaced apart for receiving at least a portion of the one or more splice trays <NUM> therebetween. Optionally, the ramp elements <NUM> are aligned in the second direction X-X with the tray support member <NUM>. However, in alternative embodiments one or both the ramp elements <NUM> may coincide with one or more tray support members <NUM>. In other words, the one or more splice trays <NUM> can be connected to the second floor <NUM> through the one or more ramp elements <NUM>.

In the preferred embodiment, the ramp element <NUM> is partitioned in a plurality of tray connecting paths <NUM> by one or more ramp guide elements <NUM> formed on the ramp element <NUM>. The tray connecting paths <NUM> are configured to receive distinct optical fibers <NUM>, in detail distinct ramp fiber portions <NUM>.

The tray connecting paths <NUM> extend, and are configured to guide the distinct optical fibers <NUM>, between a common collecting portion <NUM> of the first path <NUM> or the second path <NUM>, preferably of the second path <NUM>, and distinct fiber access openings <NUM> at distinct tray levels. Thereby, distinct optical fibers <NUM> within the second path <NUM> may be spread at the common collecting portion <NUM> between distinct tray connecting paths <NUM> of the ramp element <NUM>. Then, the tray connecting paths <NUM> will guide distinct optical fibers <NUM> to distinct splice trays <NUM>, at distinct fiber access openings <NUM>.

This preferably happens at both the two fiber access openings <NUM> of each splice tray <NUM>, i.e. at both the two ramp elements <NUM>. Moreover, the second path may have two common collecting portions <NUM> corresponding to the two ramp elements <NUM>. Therefore, the second path <NUM> can be divided in a first section from the second path internal end to a first common collecting portion <NUM>, and a second section from a second common collecting portion <NUM> and the second path external end.

Therefore, in this embodiment one and the same optical fiber <NUM>, or distinct fibers connected in series, may be guided between a first optical port <NUM> and a second optical port <NUM> along the first path <NUM>, the inclined path <NUM>, the first section of the second path <NUM>, one of the tray connecting paths <NUM> of a first ramp element <NUM>, the third path <NUM>, one of the tray connecting paths <NUM> of a second ramp element <NUM>, and the second section of the second path <NUM>.

Claim 1:
A fiber routing insert (<NUM>) for an optical junction or distribution box (<NUM>), comprising:
- a first floor (<NUM>) and a second floor (<NUM>), the second floor (<NUM>) being arranged at a raised position relative to the first floor (<NUM>),
- first guide elements (<NUM>) formed on the first floor (<NUM>), the first guide elements (<NUM>) defining a first path (<NUM>) configured to receive optical fibers (<NUM>),
- second guide elements (<NUM>) formed on the second floor (<NUM>), the second guide elements (<NUM>) defining a second path (<NUM>) configured to receive optical fibers (<NUM>),
- a channel (<NUM>) inclined to, and joining the first floor (<NUM>) and the second floor (<NUM>), the channel (<NUM>) defining an inclined path (<NUM>) configured to receive and guide optical fibers (<NUM>) between the first path (<NUM>) and the second path (<NUM>),
- one or more splice trays (<NUM>), each splice tray (<NUM>) comprising two fiber access openings (<NUM>) and third guide elements (<NUM>) defining a third path (<NUM>) configured to receive and guide optical fibers (<NUM>) between said fiber access openings (<NUM>),
characterized in that the second floor (<NUM>) has a tray opening (<NUM>) for accessing to the first floor (<NUM>), at least one splice tray (<NUM>) being rotatably connected to the second floor (<NUM>) for engaging and clearing the tray opening (<NUM>).