WO2001006293A1

WO2001006293A1 - Versatile optical fibre distribution rack

Info

Publication number: WO2001006293A1
Application number: PCT/GB2000/002718
Authority: WO
Inventors: Alain Wambeke; Frank Segers
Original assignee: Tyco Electronics Raychem Nv; Tyco Electronics Uk Ltd.
Priority date: 1999-07-15
Filing date: 2000-07-14
Publication date: 2001-01-25
Also published as: GB9916500D0

Abstract

A rack (1) for installing optical fibre distribution units (20) comprises two substantially vertical posts (3, 4) for mounting the units (2) as well as two substantially horizontal supports (5, 6) for mounting the posts (3, 4). According to the invention, at least one post is movably mounted on the supports (5, 6) to allow units (20) of different dimensions to be fitted. Preferably, both posts (3, 4) are movable and can be fastened to each other by means of arms (7, 8) so as to provide a movable frame within the rack allowing space adjustment for optimum pigtail management and/or cable termination.

Description

VERSATILE OPTICAL FIBRE DISTRIBUTION RACK

The present invention relates to a rack for installing optical fibre distribution units, such as fibre splicing units and fibre storage units. Such racks are used in e.g. telephone exchanges and may contain several (e.g. ten) distribution units and the associated optical fibre cables. Usually, a housing encloses the rack thus forming a cabinet.

The distribution units are available in different types and sizes. Typically, an empty rack is installed in the designated location and the distribution units and associated cables are fitted afterwards. When fitting the distribution units into a rack, several problems may occur.

Firstly, the rack may not have the proper internal dimensions for fitting a distribution unit of a certain type and size. That is, the vertical posts on which the distribution units are to be mounted may have an inappropriate spacing, making it difficult or even impossible to mount distribution units of a certain size. This problem can of course be overcome by providing racks having different internal dimensions, i.e. different spacings between the vertical mounting posts. However, this would require different types of racks to be manufactured and stored. Also, it could make it impossible to fit units of a certain dimension into a rack suitable for another dimension, thus jeopardising the interchangeability of distribution units between different racks.

Secondly, a varying and often increasing number of cables (including so-called "pigtails" and "jumpers") may have to be fitted into the rack or cabinet. Excess fibre optic cable is often stored in cable loops which are also accommodated in the rack, or at least in the cabinet in which the rack is mounted. As more cables and cable loops are added, the need for space increases. However, conventional racks do not allow their internal configuration to be altered, thus leaving no possibility of rearranging the available space.

The Prior Art discloses racks for electrical equipment which allow vertical posts to be mounted in different positions. Examples of such racks are disclosed in GB 2 282 527 and in JP 10234484. However, to change the position of the posts these racks have to be disassembled at least partially. There is no possibility to easily adjust the position of the posts of an assembled rack.

It is an object of the present invention to overcome these and other problems of the Prior Art and to provide a rack for installing an optical fibre unit which is easily adaptable as to the dimensions of the units to be fitted.

It is another object of the present invention to provide a rack for installing optical fibre units which allows the available space to be rearranged.

It is a further object of the present invention to provide a rack for installing optical fibre units which is flexible and versatile yet economical.

These and other objects are met by a rack for installing optical fibre distribution units, the rack comprising two substantially vertical posts for mounting distribution units, as well as two substantially horizontal supports for supporting the posts which according to the present invention is characterised in that at least one post is movably mounted on the supports.

By mounting at least one post on the supports in such a way that it is movable relative to the supports, in particular in the direction of the longitudinal axes of the supports, it is possible to adapt the spacing between the posts so as to accommodate distribution units of different sizes. The term "movably" is intended to mean that a post can be moved from one position to another position, possibly by removing the post from the rack and putting it back in, or by sliding the post along the support.

It is possible to arrange the rack according to the present invention in such a way the other post is fixedly mounted on the supports. Preferably, however, the inventive rack is arranged such that both posts are movably mounted on the supports. The latter arrangement has several advantages. In the first place, it provides greater flexibility when adapting the spacing of the posts to the particular distribution units. In the second place, it provides greater flexibility when rearranging the available space within the rack as both posts can be moved together. In the third place, it allows the distribution units to be moved even after their installation in the rack.

To provide a greater stability of the posts, the rack of the present invention is advantageously arranged in such a way that the posts are each provided with at least one arm extending towards the other post, each pair of arms being provided with a connecting member and first fastening means for fastening the arms of each pair to the connecting member. In case both posts are movable, this arrangement provides a mounting frame that can be moved relative to the supports.

Preferably, the first fastening means are releasable so as to allow the spacing of the posts to be altered, even when they had been mutually fixed so as to produce a stable mounting frame.

Additionally, or alternatively, a rack for installing optical fibre distribution units, comprising two substantially vertical posts for mounting distribution units, as well as two substantially horizontal supports for supporting the posts is according to the present invention characterised in that the rack further comprises at least one additional substantially vertical post for mounting cable spools, which additional post is movably mounted on the supports. Thus an even greater flexibility is provided by allowing the spools to be relocated within the rack. Advantageously, a spool can be fitted, and preferably refitted, at different positions on the same additional post, thus allowing height adjustment of the spool.

Advantageously, the at least one movable post is provided with a second fastening means for fastening the post to at least one of the supports. This allows the posts to be maintained in a fixed position. Preferably, also the second fastening means are releasable.

The rack of the present invention may be provided with further supports to provide a stable installation cage. Preferably, the rack is accommodated in a housing so as to provide a closed cabinet. The present invention further provides a method for installing an optical distribution unit in a rack having two substantially horizontal supports and two substantially vertical posts movably mounted on the supports, the posts being provided with arms and first fastening means for fixing the posts relative to each other, the posts further being provided with second fastening means for fixing the posts relative to the supports, the method comprising the steps of a) adjusting the spacing between the posts to match the unit and securing the first fastening means; and b) adjusting the position of the frame thus created relative to the rack and securing the second fastening means.

The present invention will be further described below by way of an exemplary embodiment while referring to the accompanying drawings, in which:

Figure 1 schematically shows, in perspective, a rack according to the present invention; Figure 2 schematically shows, in perspective, part of the rack of figure 1 in more detail; Figure 3 shows, side view, a partial cross-section of the rack of figure 2;

Figure 4 shows, in front view, the rack of figure 1 containing optical fibre distribution units.

Rack 1 of the present invention, as shown in figure 1, comprises an upper support bar 5, a lower support bar 6, a left-hand post 3 and a right-hand post 4. In the embodiment shown, the rack 1 further comprises additional bars (for example bars 9) which, together with the support bars 5 and 6, constitute a cage-like structure. While providing stability to the rack, the additional bars are not material to the present invention.

A unit, for example a box-shaped fibre distribution unit (as shown in figure 4) may be mounted on the posts 3 and 4 using suitable fastening means (not shown), such as bolts accommodated in through-holes in the posts 3 and 4. In accordance with the present invention, at least one of the posts 3 and 4 is movably mounted on the supports 5 and 6. That is, at least one of the posts is not permanently fixed to the support and may assume different positions within the rack. To this end, the movable post may be removed from the rack to be replaced in a different position, or may for example be made to slide along the supports from one position to another. Preferably both bars 3 and 4 are movable so as to provide greater flexibility.

As will be explained below with reference to Fig. 2, the posts 3 and 4 can be mutually connected to form a frame which can be moved laterally within the cage-like structure provided by the support bars 5 and 6 and the additional bars (posts) 9. In addition, the width of said frame can be easily adjusted. In other words, the present invention provides a rack having a laterally movable frame or sub-rack the width of which can be adjusted.

As shown in figure 2, the posts or vertical bars 3 and 4 are provided with arms 7 and 8 respectively. These arms are fixed to the posts by means of welding, bolts and nuts, or the like. In the embodiment shown, the arms 7 and 8 have a curved profile and slidably rest on the support bar 5 (see also figure 3). Guide rails (not shown) may optionally be provided to engage the arms in their sliding movement.

A connecting member 10, preferably having a matching profile, connects the arms 7 and 8. To this end, the connecting member 10 is provided with slots 14 which accommodate first bolts 1 1. The bolts 11 fit in suitable holes (not shown) in the arms 7 and 8 and fasten the connecting member 10 to the arms 7 and 8. When slightly released the bolts 11 can slide in slots 14, thus allowing the arms 7 and 8 to move relative to the connecting member 10.

It could be envisaged that only one of the arms 7 and 8 is movably arranged relative to the connecting member 10, the other arm being permanently fixed by for example a weld. In that case, the connecting member 10 could be integral with one of the arms. However, having both arms movable provides a greater flexibility and a greater range of movement.

Advantageously, the slots 14 have lengths corresponding to specific dimensions of the units to be fitted on the rack. That is, in the situation shown in figure 2, both bolts 11 are located in the left-hand most of their respective slots 14. The distance (spacing) between the posts 3 and 4 thus created may correspond to a first unit size A. When the left bolt is located in the left front corner of its slot and the right bolt is located in the right-hand corner of its slot, the distance between the posts 3 and 4 may correspond to a second unit size B. A third unit size C may correspond to the left bolt being right-hand corner and the right bolt being in the left-hand corner of their slots. Thus, by adapting the lengths of the slots to specific predetermined unit size, a very easy yet accurate adaptation of the spacing of the bars may be achieved. However, any unit size between B and C may also be accommodated.

When the first bolt 11 are both fastened, the posts 3 and 4 in conjunction with the arms 7 and 8 and the connecting member 10 (as well as their upper counterparts as shown in figure 1) constitute a frame which can be moved within the rack 1. This frame, or any of the posts when the first bolts 1 1 are not fastened, can be fastened to the support 6 by means of second bolts 12 which are inserted in suitable through-holes in the bars 7 and 8 to fit in suitable openings in the support 6. Advantageously, the support 6 is provided with a plurality of openings at relatively small spacings to allow the arms to be fastened in many different positions.

The cross-section of figure 3, taken along the line A- A in figure 2, shows the arm 7 resting upon the support 5. A first bolt 11 fastens the connecting member 10 to the arm 7, while the latter is fastened by a second bolt 12 to the support 6. Figure 3 also shows a flange 17 of arm 7 by which the arm is fixed to the post 3.

As shown in figure 4, a rack 1 according to the present invention may accommodate one or several optical fibre distribution units 20. The units are mounted on the posts 3 and 4 by means of suitable fastening means, for example nuts and bolts, which are accommodated in suitable openings (not shown) in the posts. In accordance with the present invention, the spacing of the posts 3 and 4 can be easily adapted to suit different distribution units. Also, the location of the distribution units relative to the rack may be altered to allow for more cable to be fitted on one of the sides of the units.

Although the rack of the present invention has been described with reference to fibre distribution units, it is equally suitable for fitting other units, in particular units involving cables and/or wiring. Such alternative units may comprise electronic devices, switches, media converters, copper network units and/or copper-fibre-conversion units. In addition to the posts 3 and 4 one or more additional posts may be incorporated in the rack 1. According to the present invention, such an additional or third post 2 serves to mount cable spools 21 and is movably relative to the supports 5 and 6. That is, the additional post 2 may be moved sideways to a different position, just as the first post 3 and the second post 4. In fact, embodiments of the rack according to the present invention can be envisaged in which the first and second posts 3, 4 are not movably mounted while the third post 2 is.

Suitable fastening elements 13, such as bolts and nuts, may be provided to fasten, preferably realeasably, the third post 2 to one or both of the supports 5 and 6.

The third post 2 may be provided with a number of attachment points (for example bolt through-holes) to allow one or more spools 21 to be fastened to the post 2 at different heights. Alternatively or additionally, the additional post 2 may be used for accommodating cable attachments, which are often comprised of a plate having a cable through-hole and one or more cable clamps. If necessary, a further additional post (not shown) may be fitted so as to fit cable spools and/or cable attachments on both sides of the first and second posts 3 and 4. Also, two or more additional posts 2 may be fitted on either side of the frame constituted by the posts 3 and 4.

It will be understood by those skilled in the art that the present invention is not limited to the embodiments shown and that many additions and modifications are possible without departing from the scope of the present invention.

Claims

1. Rack (1) for installing optical fibre distribution units (20), the rack comprising two substantially vertical posts (3, 4) for mounting distribution units (20), as well as two substantially horizontal supports (5, 6) for supporting the posts (3, 4), characterised in that at least one post (3, 4) is movably mounted on the supports (5, 6).

2. Rack according to Claim 1, wherein the other post (4, 3) is fixedly mounted on the supports (5, 6).

3. Rack according to Claim 1, wherein both posts (3, 4) are movably mounted on the supports (5, 6).

4. Rack according to any of the preceding claims, wherein the posts (3, 4) are each provided with at least one arm (7, 8) extending towards the other post, and wherein each pair of arms (7, 8) is provided with a connecting member (10) and first fastening means (11) for fastening the arms (7, 8) of each pair to the connecting member (10).

5. Rack according to Claim 4, wherein the first fastening means (11) are releasable.

6. Rack according to any of the preceding claims, wherein the at least one movable post (3, 4) is provided with second fastening means (12) for fastening the post to at least one of the supports (5, 6).

7. Rack according to claim 6, wherein the second fastening means (12) are releasable.

8. Rack for installing optical fibre distribution units (20), the rack comprising two substantially vertical posts (3, 4) for mounting distribution units (20), as well as two substantially horizontal supports (5, 6) for supporting the posts (3, 4), characterised in that the rack further comprises at least one additional substantially vertical post (2) for mounting cable spools (21), which additional post (2) is movably mounted on the supports (5, 6).

9. Rack according to claim 8, wherein an additional post (2) is provided with third fastening means (13) for fastening the additional post (2) to a support (5, 6).

10. Rack according to claim 9 wherein the third fastening means (13) are releasable.

11. Rack according to any of the preceding claims, further comprising a housing in which the supports (5, 6) are mounted.

12. Rack according to any of the preceding claims, further comprising at least one optical fibre distribution unit (2).

13. Rack according to any of the preceding claims, further comprising at least one cable spool (21).

14. Method for installing an optical distribution unit (20) in a rack (1) having two substantially horizontal supports (5, 6) and two substantially vertical posts (3, 4) movably mounted on the supports, the posts (3, 4) being provided with arms (7, 8) and first fastening means (11) for fixing the posts relative to each other by means of a connecting member (10), the posts (3, 4) further being provided with second fastening means (12) for fixing the posts (3, 4) relative to the supports (5, 6), the method comprising the steps of: a) adjusting the spacing between the posts (3, 4) to match the unit (20) and securing the first fastening means (11); and b) adjusting the position of the frame thus created relative to the rack (1) and securing the second fastening means (12).