WO2008059187A1

WO2008059187A1 - Splicing box

Info

Publication number: WO2008059187A1
Application number: PCT/GB2006/004280
Authority: WO
Inventors: Ian Griffiths
Original assignee: Prysmian Cables & Systems Uk Ltd
Priority date: 2006-11-16
Filing date: 2006-11-16
Publication date: 2008-05-22
Also published as: AU2006350892B2; AU2006350892A1; EP2084563A1

Abstract

An optical fibre splicing box (100) has at least one side wall (132), a splice container (108) for holding spliced optical fibres, for example a splice container (108), and at least one housing element. The splice container (108) and the fibre connectors (110) are each disposed at a respective oblique angle relative to the at least one side wall (132).

Description

Splicing Box

FIELD OF THE INVENTION

The invention relates to housings for connections between fibres, in particular, to splicing boxes, for splicing fibres and for storing fibres and fibre connectors.

BACKGROUND TO THE INVENTION

Devices for connecting and storing optical fibres are known. For example, WO 00/58769 discloses an optical fibre management cassette for holding a plurality of optical fibre splitters, with a first part having means for receiving fibre splitters, means for guiding fibres to or from the splitters, and a plurality of ports for allowing fibres to enter or exit the cassette, and a second part having further means for guiding fibres to or from the splitters and a further plurality of ports.

hi US 5,071,211 there is disclosed a planar connector holder for optical fibres having storage compartments for incoming fibres and a mounting region for connectors to outgoing fibres. Two storage compartments lie back-to-back on each side of a planar base of the holder, the compartments being interconnected for fibres to pass from compartment to compartment. The mounting region and the storage compartments are aligned from end-to-end of the holder. With connector mounts mounted in the mounting region, the mounts lie in planes common with the two storage compartments in a depth direction of the holder. Also included is a distribution frame and holder combination in which the holders (210) are mounted in two banks with patch cords extending between the banks and selectively between connectors.

US 2004/0175090 is directed to an organiser for optical fibres which comprises a base tray and a main tray, the trays being hingedly connected so as to provide an opened position in which access to the trays is facilitated and a closed position in which the base tray is at least partially covered. The base tray comprises at least one port for passing optical fibres into and out of the organiser and guide means for guiding optical fibres within the tray. The main tray has a first side facing away from the base tray and a second side facing towards the base tray, both the first side and the second side having guide means for guiding fibres. The base tray is provided with at least one guide for guiding fibres from the base tray towards the main tray.

In US 5,764,843, there is disclosed an optical fibre organiser which comprises a plurality of inlet ports through which optical fibres can pass, an outlet port through which fibres can pass, and an organiser drum positioned with respect to the ports such that fibres passing from the inlet ports to the outlet port are constrained by an outer surface of the drum to a minimum bend radius at least equal to the critical bend radius of the fibres, in which each inlet port has bend control means adjacent thereto to direct a fibre passing through that port towards the surface of the drum at the minimum bend radius.

US 2005/0249474 discloses an optical module for housing an optical component to which optical fibres are to be connected, the module comprising a casing, at least two round fibre guides arranged within the casing, spaced at a distance from each other and around which the optical fibres can be wound, a space between the two fibre guides for accommodating the optical component, and at least one opening provided in the casing and adjacent to one of the fibre guides for allowing external connections to be made.

GB 2,286,060 is directed to a splice tray for storing splices between optical fibres, which comprises a central splice storing area surrounded by a peripheral boundary wall. Fibre guiding and storing means may be present in the central storing area, and one or more fibre entry ports for guiding and feeding fibres into the splice tray pass through, and may be distributed around, the boundary wall.

Splicing boxes are commonly used to house fibre splices and connectors for allowing connection of fibres from a inlet cable to fibres used inside a building. Usually these boxes are positioned on the outside wall of a building and provide a means of passing fibres through the wall into the premises. Known splicing boxes have been designed in such a manner that interchangeable inserts or cassettes can be used to provide different functions within a standard splicing box.

In certain situations, greater numbers of fibres may need to be connected, or a greater variety of connectivity will be required. For example, a splicing box may be required to accommodate fibre splicing, fibre storage and connector storage. However, a larger box to accommodate more fibres and more connectivity brings disadvantages. The manufacturing of a box larger than a standard one implies a complication in the production line and an increasing of cost. Also, a larger box is often not appreciated by the customers for aesthetic reasons. In some cases, the splicing box may be required to be smaller than a standard size. A further problem where space in a splicing box is restricted is maintaining the minimum fibre bend radius, typically of 30 mm, at all points within the box.

Other known splicing boxes have contained separate components, such as splice trays, stacked one above (or beside) the other. However this requires more parts and assembly, increasing cost and making the product more complicated.

hi other words, a problem of the prior art addressed by the present invention is to provide for multiple functions, such as fibre splicing, fibre storage and connector storage, in a splicing box, without increasing the size of the box, and minimizing costs and complexity.

The present invention aims to address these problems and provide improvements upon the known devices and methods.

SUMMARY OF THE INVENTION

Aspects and embodiments of the invention are set out in the accompanying claims.

hi general terms, the invention relates to a splicing box, or an insert for a splicing box, comprising a splice container for storing fibres and splice joints, and, housing elements for storing fibres or for holding connectors for connecting fibres .

Arranging the above components one upon the other in the same plane increases the area of the box or insert. Arranging the above components one upon the other in different plane increases the thickness of the box or insert. According to the invention, at least some of the components are arranged at an oblique angle relative to a wall of the splicing box or the side of the insert. As a result, the components can be fitted, for example, in an existing splicing box of standard size, or possibly a smaller box can be used, which is better for aesthetic or other reasons. Alternatively, more space may be provided within a splicing box, for example for additional components or fibres.

Preferably, the fibre storage and connector components are provided in a single piece with the components arranged in essentially the same plane. This reduces cost and complexity.

Preferably, the components are arranged such that the splice joints and the connectors are disposed at said oblique angle.

The components can be to be formed in a single or multiple pieced insert for splicing box, the insert being interchangeable to provide different functions within the box.

Preferably, the components are in a single insert. However, it is possible to have separate inserts, such as with the splice container above with connectors below.

For the purpose of the present description and of the claims that follow, except where otherwise indicated, all numbers expressing amounts, quantities, percentages, and so forth, are to be understood as being modified in all instances by the term "about". Also, all ranges include any combination of the maximum and minimum points disclosed and include any intermediate ranges therein, which may or may not be specifically enumerated herein. For the purpose of the present description and claims as follows, as "elliptical shape" is intended a shape composed of two opposed straight sides connected by two arcs, said elliptical shape having a major axis parallel to the two opposed straight sides.

Generally, the invention provides a splicing box, or an insert for splicing box, comprising a splice container for storing fibres and for storing splice joints, and at least one housing element comprising components arranged to define an axis, for storing fibres and/or connectors for fibres, wherein the splice container is arranged at an oblique angle relative to a wall of the splicing box or a side of the insert.

Advantageously, the at least one housing element is arranged at an oblique angle relative to a wall of the splicing box or a side of the insert.

The axis defined by the components of the at least one housing element is intended as the axis of the fibre or connector housed therein.

According to a first aspect, the invention provides a splicing box comprising at least one side wall; a splice container for storing fibres and splice joints, said splice container having a major axis; and at least one housing element comprising components arranged to define an axis, wherein the splice container is are disposed at an oblique angle relative to the at least one side wall. According to a second aspect, the invention provides an insert for a splicing box the fibre splicing box having at least one side wall; the insert comprising a splice container for storing fibres and splice joints, said splice container having a major axis; and at least one housing element comprising components arranged to define an axis, and the insert being adapted to dispose the major axis of the splice container at an oblique angle relative to the at least one side wall when inserted in the fibre splicing box.

According to a third aspect, the invention provides a method of manufacturing a splicing box, or altering an existing splicing box comprising inserting an insert according to the invention a splicing box.

The term "oblique angle" is used here to denote an angle, such as an acute or obtuse angle, that is not a right angle or a multiple of a right angle.

The splice container is preferably for storing fibres and splice joints, for example, in routing channels and splice bays. The at least one housing element comprises components for holding or guiding fibres. The at least one housing element comprises, for example, at least one connector for connecting fibres, and/or components for holding such a connector.

As a result of the invention, devices for splicing, storing, connecting fibre and housing connectors can all be arranged within a splicing box, ideally in a common plane to provide easy access, whilst maintaining the minimum bend radius for the fibres. Preferably, the splice container and the at least one housing element are arranged at the same angle. More preferably, the splice container and the at least one housing element are arranged parallely.

Preferably, the splice container and the at least one housing element are in substantially the same plane, or in separate respective planes which are substantially parallel.

In one embodiment, the insert is formed of a single piece of material. This allows for reduced complexity and cost of the insert.

In one embodiment, the housing element comprises a holder for securing the fibre connectors and comprises a pair of resilieiitly deformable walls. This provides a easy and secure way for locating the connectors.

Where only a standard size of box is available, the improved space management of the aspects and embodiments described above can allow for more components and fibres to be fitted inside the standard box.

Preferably, the box or insert further comprises routing channels for guiding fibres between components. These can help to ensure that the minimum bend radius for the fibres is not compromised.

The above aspects and embodiments may be combined to provide further aspects and embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described by way of example with reference to the accompanying drawings, in which:

Figure 1 illustrates an insert and splicing box, according to an embodiment of the invention;

Figure 2 illustrates the insert of Figure 1;

Figure 3 shows a possible fibre arrangement using a splice, according to an embodiment of the invention; and

Figure 4 shows a possible fibre arrangement using a splice and connectors, according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED

EMBODIMENTS

Figure 1 illustrates a splicing box (100), according to an embodiment of the invention. More specifically, Fig. 1 shows a splicing box (100) with a cover removed to show the interior of the box.

The box (100) includes an insert (103), shown separately from the box in Fig. 2.

The box (100) includes a cable input port (102) and a cable output port (101). hi this embodiment, the input port (102) is provided on a side wall (132) of the box, and the output port (101) on the back wall of the box, though alternative positions are possible. The insert (103) includes a splice container (108) for routing, splicing and storing fibres, routing channels (104, 106) for guiding input fibres onto the splice container, routing channels (112) for guiding fibres from the cable output port (101), and housing elements (211) which, in this case, comprise holders (210) for securing connectors (110) for connecting fibres.

The splice container (108) includes a fibre guide element (116), an S-track (114) for guiding fibres from one side of the fibre guide to the other, thereby reversing the direction of the fibres housed within the fibre guide element (116), the S-track (114) being located in the centre of the fibre guide (116). The splice container (108) comprises splice bays (120) which house and store splice joints (310) (see Figs. 3 and 4).

The insert (103) is preferably made of a single piece of injection moulded plastic with the various components including the splice container (108) and the housing elements (211) being formed on a planar base.

The splice container (108) has a substantially elliptical shape composed of two opposed straight sides connected by two arcs, said elliptical shape having a major axis parallel to the two opposed straight sides. The splice bays (120) are arranged along one of the straight sides of the splice container, so that the splice bays are essentially linear or elongate and the spliced fibre ends are held in an essentially linear or elongate configuration. Similarly, the fibre connectors (110) are essentially linear or elongate.

The connectors (110) are parallel to the splice container. In other words, the straights sides of the splice container (108) and the axis of the connectors (110) are parallel, aligned such that the sections of fibres held or guided by the container (108) and the connectors (110) are substantially parallel.

The housing elements (211) comprises components arranged to define an axis oriented to hold the connectors (110) in the above configuration.

The connectors (110) and the splice container (108) are arranged such that the straight side of the splice container (108) (or in other words, the splice bays (120)) and the longitudinal axis of connectors are arranged at an acute angle θ relative to the left-hand side wall (130) of the box (100). In this case, θ is about 36 degrees.

In other embodiments, the input or output port (102),(101) may be angled, to allow an input or output fibre to be connected directly to the connector (110) a short distance inside the box (100).

In the embodiments illustrated, the connectors (110) are contained wholly within the splicing box (100). In other embodiments, one or more of the connectors (110) may be disposed at the edge of the box (100), one end of the connector thus taking the place of the input/output port (102),(101).

In this embodiment, the housing elements (211) comprise holders

(210) having walls extending from the rear plane of the insert (103) which, due to the properties of the material, are flexible enough to be pushed apart to accommodate a connector (110). The flexible walls of the holders (210) are also sufficiently resilient that once the connector has been pushed into place, the walls snap back to lock the connector in place, and form a partial closure around the body of the connector. The walls of the holders (210) may be tabbed to increase the coverage of this closure, and to permit ease of use in inserting the connector (110). For example, a tab may be provided at the tops of the walls and extend perpendicularly to the walls, in order to partially enclose a gripped connector (110). In other embodiments, the housing elements (211) may be small clips, or even a pair of walls which are sufficiently close together that there is sufficient space for the connector to be accommodated, but once in place is prevented from moving.

In this and other embodiments, the housing elements (211) may serve as additional fibre guides or routing channels, in case connectors (110) are not used.

In an alternative embodiment, the splice container (108) and the connectors (110) occupy separate planes, one on top of the other. In this arrangement, the insert (103) may be fabricated in two or more separate injection moulded pieces. These two pieces may be rigidly connected, or may be accessible via a hinging system.

The routing channels (104, 106, 112) guide the fibres among the various components of the splicing box (100) and help to ensure that the minimum bend radius is not compromised. The limiting bend radius for optical fibres can vary depending on the type of fibre, on the load applied, and on the number of bundled fibres. In the embodiments shown in the Figures and described herein, the minimum bend radius is approximately 30 mm.

In this embodiment, the box (100) is a cuboid of a standard size commonly used for external splicing boxes. The dimensions are 210 mm by 145 mm in the plane of the insert (103), and 35 mm depth. Other dimensions are possible depending of the specific needs.

In the orientation shown in Fig. 1, the left (130) and right walls, and top and bottom (132) side walls, and front and back cover plates (not shown) are respectively essentially parallel. In other embodiments, the box may lack a back cover plate, because the wall to which the box (100) is affixed provides protection at the rear side. In other embodiments, the box may lack a front cover plate, or may only be partially covered at the front. In still other embodiments, the box

(100) may have an outer frame structure; in such embodiments, the oblique angles described herein are, for example, relative to the frame structure.

An insert (103) designed to fit a particular splicing box (100) could also fit into larger boxes. Furthermore, a plurality of such inserts could be used in a box having the same planar dimensions, but having much larger depth, being designed to accommodate more than one insert.

The splicing box (100) may be of the type which remains installed on the outside of a particular building, and which may be accessed for changing the interior layout. In such case, the previous contents of the box are removed, and the new insert fitted inside the box.

The insert (103) may be installed in a splicing box when the insert or the box is manufactured. The splicing box (100) and insert (103) may be manufactured together.

With reference to Figures 3 and 4, some possible paths travelled by fibres through the splicing box (100) will now be described. Figure 3 shows a path taken by an input fibre (solid line 300) to be spliced to an output fibre (dashed line 302). The input fibre (300) entering the input port (102) is drawn to the top of the splicing box (100), following routing channels (104, 106), and enters the top end of the fibre guide (116) of the splice container (108), in an anti-clockwise direction of travel around the guide. The fibre (300) continues in an anti-clockwise fashion and is then fed round to a splice bay (120). The output fibre (302) enters through the output port (101), follows the guide (112) and is then fed through the housing element (211) which in this embodiment has no connector (110) installed, then routing channel (104), then through the S-track (114), by means of which its direction of travel around the fibre guide (116) is reversed to clockwise. The output fibre (302) continues around the top edge of the guide (116) and meets the input fibre (300) at a splice point (310), which is located in a splice bay (120). A splice protector

(304) protects the splice point (310) between the input (300) and output (302) fibres.

At each point in the path at which the fibre is bent, the minimum bend radius is maintained either by the contour of the fibre guide

(116), which provides the minimum radius, or by the S track (114), the respective curves of which also provide the minimum radius, or by the additional of routing channels (104, 106, 112).

Figure 4 illustrates a box (100) having two connectors (110) installed in respective housing elements (211), and a splice point (310) in a splice bay (120). Fibres (402, 404, 406, 408) are installed into the connector. This may be done when the box or insert is manufactured. Two of these fibres (dotted lines 402, 404 in Figure 4) are connected to the outputs of the connectors (110), and are routed through via the output port (101). Two further fibres (dashed lines 406, 408 in Figure 4) are connected to the inputs of the connectors (110), and are routed through the routing channels (104) to the fibre guide (116). In this embodiment, fibres (406, 408) are routed via the S-track (114), reversing the direction of travel around the guide to clockwise, into the splice bay (120). Here they are spliced to an input fibre (solid line 400 in Figure 4), which has been fed from the input port (102) around the guide in an anti-clockwise direction.

It should be clear that there are various possibilities available for arranging fibres within the box (100). Either an input or an output fibre may be fed through the S-track (114). The S-track (114) may be used when a change of direction of travel around the fibre guide is advantageous. The fibre guides and routing channels (104, 106, 112) may also be used as often as necessary as fibre storage for spare length of either or both the input and output fibres, accommodating several winds of any particular fibre beneath tabs in a storage area of the guide. Various particular types of output fibre may be stored in the box at the ready for connection to a particular input type. For example, one or more fibres may remain installed in the box awaiting connection to particular input fibres.

Optical fibres may also be routed within the box (100) by initially splitting out the optical fibres from a particular input optical cable. The separate fibres may then be routed as described to connectors

(110) or splices (310).

The connectors (110) may or may not be present in any particular installation, and may be replaced as necessary. The splice container (108) may at times or for a particular installation hold no splices. Ih these cases, the fibres may be routed through the housing elements (211) or the splice container (108) without being spliced or connected. At particular times, or for particular installations, the box (100) or insert (103) may not hold any splices or connectors, and may simply be used for fibre storage, with the capability to add splices and/or connectors at a later time.

It will be appreciated by those skilled in the art that the invention has been described by way of example only, and that a variety of alternative approaches may be adopted without departing from the scope of the invention, as defined by the appended claims.

Claims

1. A fibre splicing box (100), comprising: at least one side wall (130); a splice container (108) for storing fibres and splice joints (310), said splice container (108) having a major axis; and at least one housing element (211) comprising components arranged to define an axis, wherein the major axis of the splice container (108) is disposed at an oblique angle relative to the at least one side wall (130).

2. A splicing box according to Claim 1 wherein the axis of the at least one housing element (211) is disposed at an oblique angle relative to the at least one side wall (130).

3. A splicing box according to Claim 1 wherein the at least one housing element (211) comprises at least one holder (210) for at least one fibre connector (110).

4. A splicing box according to claim 3, wherein said at least one holder (210) has resiliently deformable walls.

5. A splicing box according to any preceding comprising at least one fibre connector (110).

6. A splicing box according to claim 5, wherein the at least fibre connector (110) is elongate, and the axis of the fibre connector (110) defines the angle of the fibre connector (110) relative to the side wall (130).

7. A splicing box according to any preceding claim, wherein the angle of the splice container (108) and the angle of the at least one housing element (211) are 30 to 60 degrees.

8. A splicing box according to any preceding claim, wherein the splice container (108) and the housing element (211) are disposed in substantially the same plane.

9. A splicing box according to any preceding claim, wherein the splice container (108) has essentially an elliptical shape, composed of two opposed straight sides connected by two arcs, said elliptical shape having a major axis parallel to the two opposed straight sides, said major axis defining the angle of the splice container (108) relative to the side wall (130).

10. A splicing box according to any preceding claim, further comprising routing channels (104, 106, 112) for guiding fibres within the splicing box (100).

11. A splicing box according to any preceding claim, wherein the at least one housing element (110) is contained wholly within the splicing box (100).

12. An insert for a fibre splicing box (100), the fibre splicing box having at least one side wall (130); the insert comprising a splice container (108) for storing fibres and splice joints, said splice container (108) having a major axis; and at least one housing element (211) comprising components arranged to define an axis, and the insert being adapted to dispose the major axis of the splice container (108) at an oblique angle relative to the at least one side wall (130) when inserted in the fibre splicing box.

13. An insert according to Claim 12 adapted to dispose the axis of the at least one housing element (211) at an oblique angle relative to the at least one side wall (130) when inserted in the fibre splicing box

14. An insert according to Claim 12 wherein the at least one housing element (211) comprises at least one holder (210) for at least one fibre connector (110).

15. An insert according to claim 14, wherein said at least one holder (210) has resiliency deformable walls.

16. An insert according claim 12 comprising at least one fibre connector (110).

17. An insert according to claim 16, wherein the at least fibre connector (110) is elongate, and the axis of the fibre connector (110) defines the angle of the fibre connector (110) relative to the side wall (130).

18. An insert according to any of claims 12 to 17, wherein the angle of the splice container (108) and the angle of the at least one housing element (211) are 30 to 60 degrees.

19. An insert according to any of claims 12 to 18, wherein the splice container (108) and the housing element (211) are disposed in substantially the same plane.

20. An insert according to any of claims 12 to 19 wherein the splice container (108) has essentially an elliptical shape, composed of two opposed straight sides connected by two arcs, said elliptical shape having a major axis parallel to the two opposed straight sides, said major axis defining the angle of the splice container (108) relative to the side wall (130)..

21. An insert according to any of claims 12 to 20, further comprising routing channels (104, 106, 112) for guiding fibres.

22. An insert according to any of claims 12 to 21, wherein the insert (103) is formed of a single piece of material.

23. A splicing box comprising a side wall and an insert according to any of claims 12 to 22, arranged to dispose the splice container (108) and the housing element (211) at an oblique angle relative to at least one side wall (130) of the fibre splicing box.

24. A method of manufacturing or altering a splicing box, comprising inserting the insert (103) of any of the Claims 12 to 23 into a splicing box (100).