Switching Assembly for Glass Fiber Cables of the Telecommunication and Data Technology

The invention relates to a switching assembly for glass fiber cables of the telecommunication and data technology art, and in particular to a glass fiber cable partitioning and terminal rack. The rack includes a frame supported by the rack. The rack has a jumper field for the glass fiber cable cores and with at least one magazine provided with slide-in openings for splice cassettes.

Similar switching assemblies of the aforementioned species allow the separation, for measurement purposes, of a plug connection between incoming and outgoing glass fiber cable cores. These incoming and outgoing glass fiber cable cores have to be easily accessible and have to be cross-connectable, i.e. connected in any desired manner. The switching assemblies serve, in particular, for the local fiber-glass network (overlay network) of the respective telephone companies.

A similar switching assembly of the aforementioned species is known in the art from "telcom report", vol. 10, March 1987, pages 27 to 32. Such a switching assembly is a glass fiber cable terminal rack has 60 plug connections provided in a central patch field. The glass fiber cable plug connectors are pre-assembled, in the factory, as so-called pigtails (plug connector with glass fiber cable core), which have to welded at the installation site to the glass fiber cable cores. For this purpose, in the lower section of the terminal rack, a magazine provided with slide-in openings for splice cassette is disposed. The magazine is adapted to be flapped out from the frame supported at the rack in a direction towards front, so to remove the splice cassettes. Further, as a switching assembly, a glass fiber cable partitioning rack is known in the art, which comprises three opposed splice fields, i.e. magazines provided with slide-in openings for splice cassettes. In the upper magazine of which are the cores of the interoffice cables, in the central magazine of which are the cores of the internal cables of the exchange office and in the lower magazine of which the cores of the subscribers' cables are supported.

The connections between the various glass fiber cable cores are established by switching wires. In both embodiments, 10 splice cassettes of each splice field are combined to a magazine which is located on a flap-out arm, from which the magazine can be taken out and wired at the work table.

The switching assemblies for glass fiber cables of the telecommunication and data technology described above have the disadvantage that there is relatively poor accessibility to the incoming and outgoing glass fiber cable cores, the risk of breakage, in particular when splicing, being high.

It is therefore the object of the invention to improve the switching assembly for glass fiber cable of the telecommunication and data technology such that handling is substantially easier, so that there is only a low risk that individual glass fiber cable cores are damaged, and that in particular the fiber bundle of the main glass fiber cable will not be broken.

The solution of this object is achieved, according to the invention, by the frame being pivotally supported at the rack about a vertical axis. At the frame, a jumper field with a patch field for the incoming and outgoing glass fiber cable cores is accessible from the front and from the back of the frame. On the front and/or back of the frame, at least one magazine is provided, having splice cassette slide-in openings. These slide-in openings extend substantially parallel to the back of the frame and substantially vertically to the vertical axis thereof on the opposed side of the frame. In the switching assembly according to the invention, the individual glass fiber cable cores are received in splice cassettes which are secured, when the frame is flapped-in, behind the back thereof and which, after flapping the frame out, the splice cassettes are pivoted by approximately 90.degree. towards front, so that all slide-in openings of the magazine show towards the front, and an easy removal of the splice cassettes towards front is possible. Simultaneously, the jumper field with a patch field being accessible from the front and from the back of the frame is disposed, and to which the incoming and outgoing glass fiber cable cores are connected as pigtails (plug connector with glass fiber cable core), over couplings. In the switching assembly according to the invention, there is, therefore, an easy accessibility to the incoming and outgoing glass fiber cable cores at the patch field as well as at the magazine for receiving the splice cassettes. In this way the risk of breakage of the glass fiber cable cores during assembly, e.g. when splicing, is extremely low. The considerably simpler handling of all glass fiber cores reduces the risk of breakage of individual fiber bundles of the main glass fiber cable to a minimum.

The frame can be made of two lateral spars. The jumper field, the magazine and other elements such as a termination field for electric wires can be made in modular form to fit between the spars of the frame. This gives the switching assembly a degree of customization which makes it very versatile. The spars can also be formed to provide guides for the cables and the frame or the individual modules themselves can have reorientation means for receiving and directing the lines. A termination field can also be added to connect electrical lines to the front and back of the frame.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.

In the drawings:

FIG. 1 the glass fiber cable partitioning and terminal rack in a perspective view, on the right in closed and on the left in flapped-open condition;

FIG. 2 the glass fiber cable partitioning and terminal rack in a side view, on the right in closed and on the left in flapped-open condition;

FIG. 3 a vertical section drawn in a enlarged scale through the jumper field; and

FIG. 4 a schematic representation of the cable guiding.

The glass fiber cable partitioning and terminal rack forms a switching assembly for glass fiber cables used in telecommunication and data technology. A rack 1 includes several bays having identical widths and each of the bays being formed between two vertical struts 2. Frames 3 are pivotally supported about a lateral vertical axis 26 in each of the bays. The frame is preferably formed of two lateral spars 14. Several transverse struts adapted as support locations are attached between the two lateral spars 14. The remaining sub-assemblies of the switching assembly are adapted as modules, and are also attached between the spars 14. Thereby, any desired configurations can be plugged together. A configuration is described as follows.

Each frame 3 includes a jumper field 29 with a patch field 6 and 7 being accessible on its front 4 and on its back 5. The patch fields being for incoming and outgoing glass fiber cable cores 8 and 9, as shown in FIG. 3, which are connected over pigtails 10 and 11 to glass fiber cable core couplings 12 and 13. The glass fiber cable core couplings 12 and 13 form an information link between the glass fiber cable cores on the front of the frame and the back of the frame. The pigtails 10, 11 consist each of a plug connector 32 or 33, resp., with a connected glass fiber cable core 8 or 9 resp. The glass fiber cable core couplings 12, 13 are, according to FIG. 3, connected by the patch fields 6, 7 being formed at a support plate 28 provided in recesses having a triangular cross-section. The front 4 of the frame 3 is closed underneath the front patch field 6, and is provided with lateral spars 14 extending over the full vertical length of the frame 3. The spars 14 are adapted such that therebetween, over-lengths of the exchange cable, or first set of lines, can be guided and received, as is shown on the right-side of FIG. 1.

On the back 5 of the frame 3, underneath the patch field 7, two magazines 16, 17 are attached. Slide-in openings 18 for splice cassettes 19 extend substantially parallel to the back 5 of the frame and also substantially vertical to the vertical axes 26 thereof on the opposite side of the frame 3. Each magazine 16, 17 receives several splice cassettes 19, which are shown, in FIGS. 1 and 2, in a slide-in position and in a slide-in direction outside the respective magazine 16, 17. Guides 20 and 24 and reorientation devices 25 for the glass fiber cable cores 8, 9 are present. These guides extend between the splice cassettes 19 received in the magazines 16, 17 and the patch fields 6, 7. As is shown on the right-hand side of FIG. 1, in the closed condition of the frame 3, only the patch field 6 located on the front 4 and a termination field 30 with terminal blocks 31 for connecting copper wires, if existing, are accessible. In this way only the pigtails 10 of glass fiber cable cores 8 or 9, resp., terminated at glass fiber cable core couplings 12, or the non-shown copper wires can be handled. In the open position, as shown on the left-hand side of FIG. 1, frame 3 is flapped out by approximately 90.degree.. In this open position the patch field 7, located on the back 5 of the frame 3, and the two magazines 16, 17 arranged above each other for splice cassettes 19, are accessible. The splice cassettes can then be removed from the slide-in openings 18 and can be slid back thereinto.

FIGS. 2 and 4 show the arrangement and the guiding of the first set or exchange office cables, or the first and second set of lines, A terminated in the jumper plane 35 by the couplings 12, 13. The local cables B, which are a subset of a third set of lines, terminate in the upper cassette plane 36 over a splice cassette 19 supported in the magazine 16, and the interoffice cables C, which are also a subset of the third set of lines, terminated in the lower cassette plane 37 over a splice cassette 19 supported in the magazine 17. The glass fiber cables of the third set of lines are connected in the splice cassettes 19, over splices 38, with either the second set of lines or with a fourth set of lines that lead to other splice cassettes 19. Exchange office cables A are conducted from the jumper plane 35 to the upper cassette plane 36 as well as to the lower cassette plane 37, i.e. from the jumper plane 35 to the interoffice plane in the lower cassette plane 37.