The present disclosure relates to the field of optical communications, and more specifically, relates to splice closure with high-density splice cassettes.
BACKGROUND
[0002] Optical communication networks play a vital role in today's networking infrastructure and long-haul communication. The optical communication networks are designed to meet the demands, such as high bandwidth, of end-users that leads to data, video, audio, or the like transmissions. Endeavours to meet the demands and to provide high bandwidth have been made using various techniques such as digital subscriber line, asynchronous digital subscriber line, integrated services digital network or the like. However, these conventional techniques fail to provide adequate bandwidth as well as are not economical for all the end-users.
[0003] With the advent of technology and to meet the demands, various optical fiber distribution systems and equipment have been introduced. Typically, the optical fiber distribution systems include fiber management trays mounted in telecommunications enclosures or splice closures or at other suitable locations. In general, the fiber management trays are used in managing and storing optical fibers and optical splices. Further, the fiber management trays comprise fiber routing paths that allow storage of excess length of the optical fibers without degrading optical properties of the optical fibers.
[0004] Generally, operators splice optical fibers in different fiber management trays. Firstly, single circuit (SC) trays are used to connect individual customers by splicing typically two fibers in one single thin tray. When cable elements such as the optical fibers are spliced to cable elements, mostly 12 optical fibers of that cable element are spliced in one single thicker tray. These trays are called single elements (SE) trays or cassettes.
[0005] The conventional fiber management trays come with limited splicing capacity. Further, for example, with intermittently bonded optical fiber

ribbons, although the splicing capacity may be increased in the single thicker tray, however, this leads to inability to differentiate between two fiber elements, such as the optical fibers, spliced in the single thicker tray. In cases, if two intermittently bonded optical fiber ribbons are spliced in the single thicker tray, then colour of the optical fibers will appear twice in the single thicker tray leading to confusion and faulty fiber links.
[0006] Thus, improvements in the fiber management trays are desired for increasing the splicing capacity. Accordingly, the present disclosure seeks to ameliorate the aforementioned problems by providing a high-density splice closure.
OBJECT OF THE DISCLOSURE
[0007] A primary object of the present disclosure is to provide a high-density splice closure comprising one or more splicing cassettes, where the one or more splicing cassettes are double density single element cassettes.
[0008] Another object of the present disclosure is to provide the double density single element splicing cassettes for optical transmission elements such as optical fibers and optical fiber ribbons.
[0009] Another object of the present disclosure is to improve splicing capacity.
SUMMARY
[0010] In an aspect, a splice closure is disclosed. The splice closure comprises one or more splicing cassettes. Each of the one or more splicing cassettes has a plurality of foldable sub-cassettes and each of the plurality of foldable sub-cassettes has one or more splice protectors. In an open configuration of the one or more splicing cassettes, each of the plurality of foldable sub-cassettes is hinged to adjacent foldable sub-cassettes such that each of the plurality of foldable sub-cassettes of the one or more splicing cassettes is arranged horizontally to enable splicing of one intermittently bonded ribbon (TBR) or a ribbon with 12 optical transmission elements on each of the plurality of foldable

sub-cassettes. Each of the 12 optical transmission elements has a different colour. In a closed configuration of the one or more splicing cassettes, the plurality of foldable sub-cassettes is folded on to a base cassette to form the one or more splicing cassettes, wherein the one or more splicing cassettes are stacked parallel to each other in the splice closure. The one or more splice protectors on the plurality of foldable sub-cassettes of a splicing cassette are arranged in such a manner that each of the one or more splice protectors is unaligned to the adjacent foldable sub-cassettes of the splicing cassette. Each of the plurality of foldable sub-cassettes has one or more cavities to accommodate the one or more splice protectors of the adjacent foldable sub-cassettes in the one or more splicing cassette. The one or more splice protectors are defined by a splice protector thickness, wherein each of the plurality of foldable sub-cassettes is defined by a sub-cassette thickness, wherein the splice protector thickness is greater than the sub-cassette thickness. Each of the plurality of foldable sub-cassettes is used to splice the intermittently bonded ribbon, wherein each optical transmission element of the intermittently bonded ribbon is differently coloured. The one or more splice protectors are a ribbon protector and number of the one or more splice protectors is 12.
[0011] Advantageously, the above-mentioned arrangements double the amount of splicing in the same space whilst keeping the trays perfectly separated.
[0012] These and other aspects herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the invention herein without departing from the spirit thereof.
BRIEF DESCRIPTION OF FIGURES
[0013] The invention is illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in the

drawings. The invention herein will be better understood from the following description with reference to the drawings, in which:
[0014] FIG. 1 illustrates a side cross-section of one or more splicing cassettes (trays) without a plurality of foldable sub-cassettes.
[0015] FIG. 2 illustrates a side cross-section of the one or more splicing cassettes, without the plurality of foldable sub-cassettes, stacked on top of each other.
[0016] FIG. 3 illustrates a perspective view of the one or more splicing cassettes stack without the plurality of foldable sub-cassettes.
[0017] FIG. 4 illustrates a perspective view of the one or more splicing cassettes without the plurality of foldable sub-cassettes having one or more splice protectors.
[0018] FIGS. 5-7 illustrate a side cross-section of one or more splicing cassettes with the plurality of foldable sub-cassettes.
[0019] FIG. 8 illustrates a side cross-section of the one or more splicing cassettes, with the plurality of foldable sub-cassettes, stacked on top of each other.
[0020] FIGS. 9-10 illustrate different exemplary foldable configurations utilized in the one or more splicing cassettes without the plurality of foldable sub cassettes and with the plurality of the foldable sub-cassettes respectively.
[0021] FIG. 11 depicts a splice protector from the one or more splice protectors in accordance with the present disclosure.
DETAILED DESCRIPTION
[0022] In the following detailed description of the invention, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be obvious to a person skilled in the art that the invention may be practiced with or without these specific details. In other instances, well known methods, procedures and components have not been described in details so as not to unnecessarily obscure aspects of the invention.
[0023] Furthermore, it will be clear that the invention is not limited to these alternatives only. Numerous modifications, changes, variations, substitutions

and equivalents will be apparent to those skilled in the art, without parting from the scope of the invention.
[0024] The accompanying drawings are used to help easily understand various technical features and it should be understood that the alternatives presented herein are not limited by the accompanying drawings. As such, the present disclosure should be construed to extend to any alterations, equivalents and substitutes in addition to those which are particularly set out in the accompanying drawings. Although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are generally only used to distinguish one element from another.
[0025] The key idea of the present disclosure is to provide a unique design and arrangement of splicing cassettes in order to achieve a high-density splicing cassette. The high-density splicing cassette (tray) is a double-density single element splicing cassette that helps increasing capacity of telecommunications enclosures such as splice enclosures/closures or terminals. In general, the splice enclosures/closures may be mounted in indoor as well as in outdoor environments and are used to protect cable elements such as stripped fiber optic cable and fiber optic splices. The splice enclosures may be mounted on poles or walls, injunction boxes, in below-grade vaults or the like. The splice enclosures act as a housing, in which a plurality of optical transmission elements is fanned out that are situated at the end of fiber routing paths. The splicing cassette(s), also termed as a splicing tray(s), mounted in the splice enclosures picks up the plurality of optical transmission elements and their reserves. The splicing cassette may be made from plastic and other suitable material. The splicing cassette is a removable element in order to assemble the plurality of optical transmission elements with a splice unit. The plurality of optical transmission elements may be, but not limited to, optical fibers and optical fiber ribbons such as intermittently bonded optical fiber ribbon or the like.
[0026] In general, an optical fiber refers to a medium associated with transmission of information over long distances in form of light pulses. The optical fiber uses light to transmit voice and data over long distances. Further, the

intermittently bonded optical fiber ribbon comprises a plurality of optical fibers placed in parallel to each other and bonded intermittently with a special material such as matrix material to impart rolling capability along a width of the intermittently bonded optical fiber ribbon.
[0027] In an aspect, a splice closure is disclosed. The splice closure comprises one or more splicing cassettes. Each of the one or more splicing cassettes has a plurality of foldable sub-cassettes and each of the plurality of foldable sub-cassettes has one or more splice protectors. In an open configuration of the one or more splicing cassettes, each of the plurality of foldable sub-cassettes is hinged to adjacent foldable sub-cassettes such that each of the plurality of foldable sub-cassettes of the one or more splicing cassettes is arranged horizontally to enable splicing of one intermittently bonded ribbon (TBR) or a ribbon with 12 optical transmission elements on each of the plurality of foldable sub-cassettes. Each of the 12 optical transmission elements has a different colour. In a closed configuration of the one or more splicing cassettes, the plurality of foldable sub-cassettes is folded on to a base cassette to form the one or more splicing cassettes, wherein the one or more splicing cassettes are stacked parallel to each other in the splice closure. The one or more splice protectors on the plurality of foldable sub-cassettes of a splicing cassette are arranged in such a manner that each of the one or more splice protectors is unaligned to the adjacent foldable sub-cassettes of the splicing cassette. Each of the plurality of foldable sub-cassettes has one or more cavities to accommodate the one or more splice protectors of the adjacent foldable sub-cassettes in the one or more splicing cassette. The one or more splice protectors are defined by a splice protector thickness, wherein each of the plurality of foldable sub-cassettes is defined by a sub-cassette thickness, wherein the splice protector thickness is greater than the sub-cassette thickness. Each of the plurality of foldable sub-cassettes is used to splice the intermittently bonded ribbon, wherein each optical transmission element of the intermittently bonded ribbon is differently coloured. The one or more splice protectors are a ribbon protector and number of the one or more splice protectors is 12.

[0028] Now, referring to the figures. FIG. 1 illustrates a side cross-section 100 of one or more splicing cassettes (trays) 102 without a plurality of foldable sub-cassettes. FIG. 2 illustrates a side cross-section of the one or more splicing cassettes stack 200 without the plurality of foldable sub-cassettes, where the one or more splicing cassettes stacked on top of each other. FIG. 3 illustrates a perspective view of the one or more splicing cassettes stack 200 without the plurality of foldable sub-cassettes. FIG. 4 illustrates a perspective view of the one or more splicing cassettes, without the plurality of foldable sub-cassettes, having one or more splice protectors 104.
[0029] The one or more splicing cassettes (trays) may be used or incorporated in a splice closure or enclosure. The one or more splicing cassettes 102 may include one or more cavities 106 (as shown in FIG. 2) to accommodate the one or more splice protectors 104. Each of the one or more splice protectors 104 may protect spliced plurality of optical transmission elements such as optical fibers, intermittently bonded optical fiber ribbons etc. In an example, each of the one or more splice protectors 104 may protect spliced 12fiber intermittently bonded optical fiber ribbon.
[0030] Alternatively, the one or more cavities 106 may accommodate any other suitable components used in conjunction with the splice closure.
[0031] Referring to FIG. 2, the one or more splicing cassettes stack 200 may be formed by the one or more splicing cassettes 102 arranged in a stacked manner. The one or more splicing cassettes 102 may be connected with each other removably and rotatably via hinged structures or any other suitable means as shown in FIG. 3. The one or more splicing cassettes 102 may be rotatably hinged to each other along an axis at same back plane (as shown by arrows in FIG. 3).
[0032] Referring back to FIG. 2, the one or more splicing cassettes stack 200 may be removably hinged to a supporting structure 202 along an axis through an attachment means 204 from one side. The attachment means 204 (shown in FIG. 4) may be any type of fasteners, screws or elements having snap-fit capabilities.

[0033] In the one or more splicing cassettes stack 200, the one or more splice protectors 104 may be protruded on adjacent cassettes/trays and may be placed in such a manner that the one or more splice protectors are unaligned i.e., not under each other.
[0034] Each splicing cassette of the one or more splicing cassettes 102 may be defined by a thickness and each splice protector of the one or more splice protectors 104 may be defined by a splice protector diameter and a splice protector thickness, where each of the one or more splicing cassettes 102 may have the thickness less than the splice protector diameter. This dimensional aspect allows the protrusion of each of the one or more splice protectors 104 on the adjacent cassettes/trays in the one or more splicing cassettes stack 200 as depicted in FIG. 2. In an example, each of the one or more splice protectors 104 may have the splice protector diameter of 5.8mm. Alternatively, the splice protector diameter of each of the one or more splice protectors 104 may vary.
[0035] For instance, each of the one or more splicing cassettes 102 has three splice protectors that can accommodate three intermittently bonded optical fiber ribbons in each of the three splice protectors. Alternatively, number of splice protectors may be more than or less than three in each of the one or more splicing cassettes 102. Further, each intermittently bonded optical fiber ribbon may accommodate 12 optical fibers of different colour. Alternatively, the number and colour of the optical fibers in the intermittently bonded optical fiber ribbon may vary. In an example, each of the one or more splicing cassettes 102 may have three optical fibers of same colour.
[0036] Advantageously, each of the one or more splicing cassettes 102 may have the one or more cavities to accommodate protruded splice protectors (or any other component) on the adjacent cassettes that leads to high density packing of the plurality of optical transmission elements.
[0037] FIG. 5 illustrates a side cross-section of one or more splicing cassettes/trays 500 with a base cassette 502 and the plurality of foldable sub-cassettes (trays) 502a, 502b in a closed configuration. FIG. 6 illustrates a side cross-section of the one or more splicing cassettes/trays 500 in a semi-open

configuration. FIG. 7 illustrates a side cross-section of the one or more splicing cassettes/trays 500 in an open configuration. FIG. 8 illustrates a side cross-section of the one or more splicing cassettes stack 600 comprising the one or more splicing cassettes 500 having the base cassette 502 and the plurality of foldable sub-cassettes 502a, 502b stacked in parallel. The one or more splicing cassettes/trays 500 may be incorporated in the splice enclosure (or closure).
[0038] Referring to FIG. 5, the one or more splicing cassettes 500 having
the plurality of foldable sub-cassettes 502a, 502b are formed using a main
cassette/tray 502 and the plurality of foldable sub-cassettes/sub-trays 502a, 502b,
where the main cassette 502 acts as the base cassette/tray. Each of the plurality of
foldable sub-cassettes 502a, 502b is connected with each other through a
connecting means 504 that allows connection as well as movement of the plurality
of foldable sub-cassettes 502a, 502b in operational condition as depicted in FIG. 6
and FIG. 7. The plurality of foldable sub-cassettes 502a, 502b is foldable in
accordance with an axis of the base cassette/tray 502. For illustration purposes,
only two foldable sub-cassettes 502a, 502b have been shown, however, number of
the plurality of foldable sub-cassettes may be more than two 502a, 502b,
502c 502n.
[0039] Each of the base cassette 502 and the plurality of foldable sub-cassettes 502a, 502b may include the one or more splice protectors 104. This arrangement forms the one or more splicing cassettes 500 with three splice protectors.
[0040] In this configuration, the one or more splicing cassettes 500 having the base cassette 502 and the plurality of foldable sub-cassettes 502a, 502b may have the one or more cavities 106, where each of the one or more splice protectors 104 may be protruded into adjacent sub-cassette and the base cassette and may be unaligned to each other. That is, the one or more splicing cassettes 500 having the base cassette 502 and the plurality of foldable sub-cassettes 502a, 502b may have the one or more cavities 106 to accommodate the one or more splice protectors 104 in the adjacent cassettes as depicted in FIGS. 5-7.

[0041] In an implementation, the base cassette 502 may be a thicker cassette, whereas the plurality of foldable sub-cassettes 502a, 502b may be thinner sub-cassettes as compared to the base cassette 502. In addition, each of the plurality of foldable sub-cassettes may be defined by a sub-cassette thickness, where the splice protector thickness is greater than the sub-cassette thickness. The base cassette 502 having the plurality of foldable sub-cassettes 502a, 502b, that are hinged and foldable, creates two separate zones (i.e., the base cassette and the plurality of foldable sub-cassettes arranged horizontally). The plurality of optical transmission elements may be spliced in each of the base cassette 502 and the plurality of foldable sub-cassettes 502a, 502b, i.e., in the two separate zones. For example, one 12F intermittently bonded optical fiber ribbon or a ribbon with 12 optical transmission elements, wherein each of the 12 optical transmission elements may have different colour, may be spliced in each of the thick cassettes and thin sub-cassettes in two separate zones.
[0042] The plurality of foldable sub-cassettes 502a, 502b may be folded endlessly from the base cassette 502 like an endless chain. The plurality of foldable sub-cassettes 502a, 502b, 502c may hinge at one axis i.e., at same backplane with the help of the hinge 504 as shown in FIG. 9. For example, if the number of the plurality of foldable sub-cassettes is 3, then all 3 foldable sub-cassettes may hinge at the same backplane. Similarly, if the number of the plurality of foldable sub-cassettes is 4, then all 4 foldable sub-cassettes may hinge at the same backplane. The one or more splicing cassette 500 may utilize a book-fold configuration 700 as shown in FIG. 9 and a Z-fold configuration 800 as shown in FIG. 10 to stack the plurality of foldable sub-cassettes 502a, 502b, 502c...502n one to the other. Other suitable folding configurations may also be utilized.
[0043] Referring to FIG. 8, the one or more splicing cassettes stack 600 may be formed by the one or more splicing cassettes 500 arranged in a stacked manner. The one or more splicing cassettes stack 600 may be removably hinged to the supporting structure 202 along an axis through the attachment means from one

side. The attachment means may be any type of fasteners, screws or elements having snap-fit capabilities.
[0044] As mentioned earlier that with intermittently bonded optical fiber ribbons, although the splicing capacity may be increased in conventional single thicker cassettes/trays, however, this leads to inability to clearly differentiate between two optical transmission elements, such as the optical fibers, spliced in the conventional single thicker cassette/tray. For example, if two intermittently bonded optical fiber ribbons are spliced in the conventional single thicker cassette, then colour of the optical fibers will appear twice in the conventional single thicker cassette leading to confusion and faulty fiber links.
[0045] By splitting the conventional single thicker cassette into the plurality of foldable sub-cassettes 502a, 502b, the plurality of the optical transmission elements, such as two intermittently bonded optical fiber ribbons, may be spliced in the same thickness as the conventional single thicker cassette (or single element cassette) by keeping each of the plurality of the optical transmission elements to be separated.
[0046] Thus, the one or more splicing tray 500 consisting of the plurality of foldable sub-cassettes 502a, 502b,... .502n that fold into each other and into the base cassette 502, doubles the amount of splicing in the same space whilst keeping the cassettes perfectly separated.
[0047] Therefore, the aforementioned arrangement allows packing more splices in a given volume and increases density of the splice enclosure.
[0048] FIG. 11 depicts the splice protector from the one or more splice protectors 104 in accordance with the present disclosure. The splice protector 104 includes an outer tube 902, a strength member 904 and an inner tube 906. The outer tube 902 is a shrink tube that encapsulates the strength member 904 and the inner tube 906. The outer tube 902 may be made from any suitable material, such as, but not limited to, polymers, having capability of shrinking. The strength member 904 may be made from ceramic, stainless steel or other suitable material. The inner tube 906 is a fiber tube, where the fiber tube encapsulates the plurality of optical transmission elements. The outer tube 902 and the strength member 904

protects the inner tube 906, thereby protecting the plurality of optical transmission elements to avoid losses in optical properties of the plurality of optical transmission elements. The splice protector 104 may have the splice protector diameter of 5.8 millimeters as mentioned above. The splice protector 104 may be made flexible and formed in such a way that when inserted/placed in a cavity of the one or more cavities 106, the splice protector 104 may deform and take shape of the cavity. The splice protector may be a ribbon protector. Number of the one or more splice protectors may be 12.
[0049] Conditional language used herein, such as, among others, "can," "may," "might," "may," "e.g.," and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain alternatives include, while other alternatives do not include, certain features, elements and/or steps. Thus, such conditional language is not generally intended to imply that features, elements and/or steps are in any way required for one or more alternatives or that one or more alternatives necessarily include logic for deciding, with or without other input or prompting, whether these features, elements and/or steps are included or are to be performed in any particular alternative. The terms "comprising," "including," "having," and the like are synonymous and are used inclusively, in an open-ended fashion, and do not exclude additional elements, features, acts, operations, and so forth. Also, the term "or" is used in its inclusive sense (and not in its exclusive sense) so that when used, for example, to connect a list of elements, the term "or" means one, some, or all of the elements in the list.
[0050] Disjunctive language such as the phrase "at least one of X, Y, Z," unless specifically stated otherwise, is otherwise understood with the context as used in general to present that an item, term, etc., may be either X, Y, or Z, or any combination thereof (e.g., X, Y, and/or Z). Thus, such disjunctive language is not generally intended to, and should not, imply that certain alternatives require at least one of X, at least one of Y, or at least one of Z to each be present.
[0051] While the detailed description has shown, described, and pointed out novel features as applied to various alternatives, it can be understood that

various omissions, substitutions, and changes in the form and details of the devices or algorithms illustrated can be made without departing from the scope of the disclosure. As can be recognized, certain alternatives described herein can be embodied within a form that does not provide all of the features and benefits set forth herein, as some features can be used or practiced separately from others.

CLAIMS
We Claim:

1. A splice closure comprising:
one or more splicing cassettes (500), wherein each of the one or more splicing cassettes (500) has a plurality of foldable sub-cassettes (502a, 502b), wherein each of the plurality of foldable sub-cassettes (502a, 502b) has one or more splice protectors (104).
2. The splice closure as claimed in claim 1, wherein, in an open configuration of the one or more splicing cassettes (500), each of the plurality of foldable sub-cassettes (502a, 502b) is hinged to adjacent foldable sub-cassettes such that each of the plurality of foldable sub-cassettes (502a, 502b) of the one or more splicing cassettes (500) is arranged horizontally to enable splicing of one intermittently bonded ribbon (IBR) or a ribbon with 12 optical transmission elements on each of the plurality of foldable sub-cassettes (502a, 502b), wherein each of the 12 optical transmission elements has a different colour.
3. The splice closure as claimed in claim 1, wherein, in a closed configuration of the one or more splicing cassettes (500), the plurality of foldable sub-cassettes (502a, 502b) is folded on to a base cassette (502) to form the one or more splicing cassettes (500), wherein the one or more splicing cassettes (500) are stacked parallel to each other in the splice closure.
4. The splice closure as claimed in claim 1, wherein the one or more splice protectors (104) on the plurality of foldable sub-cassettes (502a, 502b) of a splicing cassette (500) are arranged in such a manner that each of the one or more splice protectors (104) is unaligned to the adjacent foldable sub-cassettes of the splicing cassette (500).
5. The splice closure as claimed in claim 1, wherein each of the plurality of foldable sub-cassettes (502a, 502b) has one or more cavities (106) to

accommodate the one or more splice protectors (104) of the adjacent foldable sub-cassettes in the one or more splicing cassettes (500).
6. The splice closure as claimed in claim 1, wherein the one or more splice protectors (104) are defined by a splice protector thickness, wherein each of the plurality of foldable sub-cassettes (502a, 502b) is defined by a sub-cassette thickness, wherein the splice protector thickness is greater than the sub-cassette thickness.
7. The splice closure as claimed in claim 1, wherein each of the plurality of foldable sub-cassettes (502a, 502b) is used to splice the intermittently bonded ribbon, wherein each optical transmission element of the intermittently bonded ribbon is differently coloured.
8. The splice closure as claimed in claim 1, wherein the one or more splice protectors (104) are a ribbon protector and number of the one or more splice protectors is 12.