EP4330751A1

EP4330751A1 - Optical fiber management trays with increased splice management capacity

Info

Publication number: EP4330751A1
Application number: EP22796804.7A
Authority: EP
Inventors: Bart Mattie Claessens; Jari KAPITEYN
Original assignee: Commscope Technologies LLC
Current assignee: Commscope Technologies LLC
Priority date: 2021-04-30
Filing date: 2022-04-29
Publication date: 2024-03-06
Also published as: EP4330751A4; WO2022232511A1

Abstract

Optical fiber management trays for optical fiber closures. The trays are shaped and otherwise configured to maximize usable space within closures having particular configurations, such as dome closures having dome covers with substantially round cross-sections and cylindrical or frustoconical interior closure volumes. The trays include features for maximizing the number and/or density of fiber splices that can be supported on a tray of a given, fixed size and shape, while conforming with minimum bend radius limitations of the fibers, and/or other routing requirements of the fibers.

Description

OPTICAL FIBER MANAGEMENT TRAYS WITH INCREASED SPLICE

MANAGEMENT CAPACITY

Cross-Reference to Related Application

This application is being filed on April 29, 2022 as a PCT International Patent Application and claims the benefit of U.S. Patent Application Serial No. 63/182,080, filed on April 30, 2021, the disclosure of which is incorporated herein by reference.

Background

Fiber optic cables carry optical fibers used to transmit optical signals between providers and subscribers. Typically, large cables, such as trunk cables or “main” cables, carry a large number of fibers. The fibers of the main cable are spliced, split, optically connected to other fibers (e.g., via fiber optic connectors), or otherwise managed and routed to a desired destination, (e.g., a subscriber building). Due to the large number of fibers that need to be managed and routed, the main cable is often terminated in a fiber optic splice closure. Such fiber optic splice closures typically include an outer ruggedized and sealable shell defining an interior volume and one or more sealable ports for sealed cable entry to the interior. The closures can be adapted for outdoor or indoor use. The interior volume of a splice closure typically houses structures and equipment, such as splice trays, to organize and route fibers to facilitate both storing of fibers and routing of fibers to their desired destinations.

Summary

In general terms, the present disclosure is directed to optical fiber management trays that can be housed in telecommunications closures, the optical fiber management trays having one or more features that optimize multiple fiber routing factors.

According to certain aspects, the present disclosure is directed to improved telecommunications closures.

According to certain aspects, the present disclosure is directed to improved optical fiber organizer assemblies of telecommunications closures. According to certain aspects, the present disclosure is directed to improved fiber management trays for telecommunications applications.

According to certain aspects, the present disclosure is directed to improved methods of routing optical fibers using fiber management trays.

According to certain aspects, the present disclosure is directed to improved methods supporting splices of optical fibers using fiber management trays.

According to certain aspects, the optimized routing factors include maximizing the number of fiber to fiber splices supported by a fiber management tray of fixed, predetermined size and shape (e.g., a tray of standard size and shape).

According to certain aspects, the optimized routing factors include fiber routing paths on the tray that maintain minimum bend radius limitations for the routed and spliced fibers.

According to certain aspects, the optimized routing factors include fiber routing paths and features on the tray that provide robust retention of fibers on the tray and minimize straying of portions of fibers from the tray.

According to certain aspects, the optimized routing factors include tray features that allow for selectable entry locations of fibers onto the tray and a selectable crossover channel for reversing the routing direction of fibers on the tray.

According to certain aspects, the optimized routing factors include providing a tray that is structurally asymmetrical about a central axis defined by the tray and perpendicular to a hinge axis defined by the tray.

According to certain aspects, the optimized routing factors include maximizing the number of fiber to fiber splices supportable on a fiber management tray that is shaped to be stacked in a stack of trays within the domed portion of a domed telecommunications closure.

In some examples, the domed portion defines a substantially cylindrical or frustconical interior closure volume.

According to certain aspects, the optimized routing factors include maximizing the number of fiber to fiber splices supportable by a fiber management tray that is substantially trapezoidal.

In accordance with certain specific aspects of the present disclosure, an optical fiber management tray includes: a hinge portion configured to pivotally mount the tray to a tray support about a hinge axis defined by the hinge portion; a fiber management surface; and a wall projecting away from the fiber management surface and defining at least a portion of an outer perimeter of the fiber management surface, the wall including a straight wall portion that extends along a wall axis that is oblique to the hinge axis; and a mounting structure configured to mount a splice body holder block to the fiber management surface, the splice body holder block including a channel for receiving a splice body, the channel defining a longitudinal axis, the mounting structure being positioned to mount the splice body holder block to the fiber management surface such that the longitudinal axis is parallel to the wall axis.

In accordance with certain specific further aspects of the present disclosure, an optical fiber management tray extending from a proximal end to a distal end, includes: a mounting portion positioned at the proximal end and configured to pivotally mount the tray to a tray support; a fiber management surface; and at least one wall projecting away from the fiber management surface and defining at least a portion of an outer perimeter of the fiber management surface, the at least one wall including, at opposite sides of the fiber management surface, straight wall portions that extend along wall axes that converge toward each either as they extend toward the distal end; and mounting structures configured to mount splice body holder blocks to the fiber management surface, the splice body holder blocks including channels for receiving splice bodies, the channels defining longitudinal axes, the mounting structures being positioned to mount splice body holder blocks such that each splice body holder block abuts one of the straight wall portions and such that the longitudinal axes are parallel to one of the wall axes.

In accordance with certain specific further aspects of the present disclosure, an optical fiber management tray, includes: a hinge portion configured to pivotally mount the tray to a tray support about a hinge axis defined by the hinge portion; a fiber management surface including a splice body holder block region, the region including mounting structures configured to mount one or more splice body holder blocks to the fiber management surface at the region such that the one or more blocks cover a center of the fiber management surface, the splice body holder block including a channel for receiving a splice body, the channel defining a longitudinal axis, the mounting structures being positioned to mount the one or more blocks to the fiber management surface such that the longitudinal axis is non-parallel to the hinge axis.

In accordance with certain specific further aspects of the present disclosure, an optical fiber management tray, includes: a tray body, including: a hinge portion configured to pivotally mount the tray to a tray support about a hinge axis defined by the hinge portion; a fiber management surface including a splice body holder block region, the region including mounting structures configured to mount one or more splice body holder blocks to the fiber management surface at the region; and fiber routing structures projecting from the fiber management surface and partially defining the splice body holder block region, wherein the fiber routing structures are positioned and configured such that the tray body is asymmetrical about a central axis defined by the tray body and perpendicular to the hinge axis.

A variety of additional aspects will be set forth in the description that follows. The aspects relate to individual features and to combinations of features. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the broad inventive concepts upon which the embodiments disclosed herein are based.

Brief Description of the Drawings

The following drawings are illustrative of particular embodiments of the present disclosure and therefore do not limit the scope of the present disclosure. The drawings are not necessarily to scale and are intended for use in conjunction with the explanations in the following detailed description. Embodiments of the present disclosure will hereinafter be described in conjunction with the appended drawings, wherein like numerals denote like elements.

FIG. 1 is a perspective view of an example telecommunications closure that can house an optical fiber management assembly having stacks of fiber management trays according to the present disclosure.

FIG. 2 is a further perspective view of the closure of FIG. 1.

FIG. 3 is a partially exploded view of the closure of FIG. 1, and showing stacks of prior art fiber management of an optical fiber management assembly that can be housed in the closure.

FIG. 4 is a side view of the closure of FIG. 1.

FIG. 5 is a cross-sectional view of the closure of FIG. 1 taken along the line A-A in FIG. 4.

FIG. 6 is a perspective view of an example fiber management tray according to the present disclosure. FIG. 7 is a further perspective view of the tray of FIG. 6.

FIG. 8 is a perspective, exploded view of the tray of FIG. 6.

FIG. 9 is a further perspective, exploded view of the tray of FIG. 6.

FIG. 10 is a top, planar view of the tray of FIG. 6.

FIG. 11 is a perspective view of a further example fiber management tray according to the present disclosure.

FIG. 12 is a further perspective view of the tray of FIG. 11.

FIG. 13 is a perspective, exploded view of the tray of FIG. 11.

FIG. 14 is a further perspective, exploded view of the tray of FIG. 11.

FIG. 15 is a top, planar view of the tray of FIG. 11.

FIG. 16 is a perspective view of the tray body of the tray of FIG. 11.

FIG. 17 is a view of the tray of FIG. 6 showing an example routing and splicing scheme for optical fibers on the tray.

FIG. 18 is a view of the tray of FIG. 11 showing an example routing and splicing scheme for optical fibers on the tray.

FIG. 19 is a view of the tray of FIG. 11 showing a further example routing and splicing scheme for optical fibers on the tray.

FIG. 20 is a view of the tray of FIG. 11 showing a further example routing and splicing scheme for optical fibers on the tray.

Detailed Description

Various embodiments of the present invention will be described in detail with reference to the drawings, wherein like reference numerals represent like parts and assemblies throughout the several views. Reference to various embodiments does not limit the scope of the invention, which is limited only by the scope of the claims attached hereto. Additionally, any examples set forth in this specification are not intended to be limiting and merely set forth some of the many possible embodiments for the claimed invention.

Referring to FIGS. 1-5, the fiber optic closure 10 includes a first housing piece 12 (in this case, a dome), and a second housing piece 14 configured to cooperate with the first housing piece to define a sealable and re-enterable telecommunications closure for managing optical fibers. The first and second housing pieces 12, 14 define an interior closure volume 15 in which fiber managing equipment, including an optical fiber organizer assembly, can be housed.

The closure 10 defines a central axis 26.

The interior closure volume 15 can be substantially cylindrical or frustoconical. A cross-section of the closure volume 15 perpendicular to the axis 26 is circular as shown in FIG. 5, or substantially circular. In other examples, the cross-section of the closure volume can be substantially square or rectangular, e.g., with rounded comers.

A clamp ring 16 having a clamp can be used to clamp and seal together the housing pieces 12 and 14.

Cables carrying optical fibers can sealingly enter the closure volume 15 via sealable ports 19 defined by the second housing piece 14. Such cables can include trunk cables, feeder cables, branch cables, and distribution cables (also known as drop cables). Typically, optical fibers from one cable entering the closure are spliced to optical fibers of one or more other cables entering the closure to establish an optical signal path at the closure 10 from a provider side cable to one or more customer side cables, or an optical signal between a branch cable and any of: another branch cable, a trunk cable, a feeder cable, or a distribution cable. Branch cables can be used to route optical signals from one telecommunications closure to another telecommunications closure.

In addition to splicing, other fiber managing activities can be performed with telecommunications equipment housed within the closure volume 15. Such fiber managing activities can include, without limitation, indexing fibers, storing fibers (typically in one or more loops) and splitting fibers.

Splices, such as mechanical splices or fusion splices, can be performed at the factory or in the field, e.g., at the closure 10 positioned in the field.

The cables entering the closure can include fibers of different configurations such as loose fibers and fiber ribbons. The fiber ribbons can be flat ribbons or reliable ribbons. The loose fibers can be individual fibers or bundled loose fibers protected by a common protective sheath or tube. For fiber ribbons, the fibers of the entire ribbon can be spliced to the fibers of a corresponding fiber ribbon at the same time, e.g., using a mass fusion splicing procedure. In addition to time efficiency advantages, mass splices also generally require less space to be occupied per splice, as the splice body is shared and distributed amongst multiple fibers.

Splice bodies protect the splices both in the case of individual fiber splices and mass fiber splices, such as mass fusion splices. The splice bodies are held in splice holders. Fiber management trays 24 include such splice holders. The fiber management trays 24 can be stacked in stacks 22 back to back on a framework 20. The trays 24 are pivotal relative to the framework such that a desired tray in the stack can be accessed by pivoting the trays above the desired tray away from the desired tray. The stacks 22 of trays 24 and the framework 20 form part of an optical fiber organizer or organizer assembly 18 that is configured to be seabngly stored within the interior closure volume 15 and re accessed when needed to service the assembly 18, such as to route or splice additional fibers between incoming and outgoing cables.

The dome shape of the housing piece 12 can be suitable for particular use applications, such as aerial or handhole applications. For example, a dome shape closure 10 can be particularly suited for aerial mountings of the closure at or near telephone poles, and the like.

Generally, it is desirable to make closures, including the closure 10, as small as possible given the constraints of the location where the closure is placed or mounted.

Thus, it is generally desirable to maximize functional usage of the interior closure volume

15. For example, it can be desirable to maximize the number of fiber to fiber splices that can be supported by the fiber management trays housed in the closure 10. By maximizing the number of fiber to fiber splices per closure of a given size and shape, advantageously, a smaller number of closures is required to service a given area, such as a residential neighborhood. Requiring fewer closures can reduce cost to the service provider (and thereby possibly lower prices charged to the consumer) in terms of, e.g., fees that may be charged for mounting or placing a closure, and in terms of closure maintenance costs.

The trays 24 are prior art trays having a substantially trapezoidal shape. The trays 24 are shaped to conform somewhat to the circular profile of the interior closure volume 15, while providing gaps 30 adjacent the stacks 22 within the closure volume where tubes of fibers or other equipment belonging to the organizer assembly 18 or extensions of the cables entering the closure can be stored. Thus, in at least some respects, the outer shape and size of the tray 24 is optimized for the shape of the domed housing piece 12 of the dome closure 10. The substantially trapezoidal shape of the tray 24 can be optimized for other dome shapes as well, such as domes with substantially rectangular or square cross- sections.

Referring now to FIGS. 6-10, a fiber management tray 40 will be described. The tray 40 includes a tray body 41 that can be of unitary construction (e.g., from a single mold of material, such as a polymeric material). The tray 40 also includes one or more fiber management components that are selectively mounted to the tray body 41, such as splice body holder blocks 140. A splice body holder block 140 can also be referred to as a splice chip.

The tray body 41 has the same or substantially the same outer dimensions, shape, and size as the tray 24 described above in connection with FIGS. 3 and 5. That is, the outer shape and dimensions of the tray body 41 are optimized for the domed housing piece 12 of the closure 10 (FIG. 1) or for another dome housing piece, such as a dome housing piece with a substantially rectangular or square cross-section.

The tray 40 is configured to be stacked in a stack of the trays 40 with each tray pivotally mounted to a framework, in the same manner as described above in connection with the organizer assembly 18 (FIG. 3).

As with the tray 24, the tray 40 is substantially trapezoidal in shape. The tray extends from a top 56 to a bottom 58 along a first axis 60. The tray extends along a second axis 42 from a proximal end 44 to a distal end 46. The tray extends along a third axis 54 from a first side 50 to a second side 52. The axes 42, 54 and 60 are mutually perpendicular to one another. The axes 42 and 54 intersect each other at a point 62. The point 62 projects along the axis 60 onto the center Cl of the fiber management surface 48 of the tray 40.

The center C 1 is defined as the point on the fiber management surface 48 where two perpendicular dimensions of the fiber management surface 48 that are parallel to the axes 42 and 54, respectively, and aligned therewith parallel to the axis 60, intersect and are bisected.

The tray body 41 includes walls 64, 66 projecting away from the fiber management surface 48 parallel to the axis 60. The walls 64, 66 define an outer perimeter of the fiber management surface 48.

The tray body 41 includes a mounting portion 70. The mounting portion 70 includes hinge portions. The hinge portions include a squared hinge pin 72 and hinge pegs 74 that are received in complementary mounting features of a tray support, such as the tray support plate 31 of the framework 20 (FIG. 3). When mounted to a tray support, the hinge portions of the tray body 41 form a hinge with the tray support, such that the tray body 41 can be pivoted relative to the tray support about a hinge axis 76 defined by the hinge portions of the tray body 41. In particular, one or more trays 40 in a stack of the trays mounted to the tray support can be pivoted away from another tray in the stack that is to be worked on, e.g., for fiber routing and/or splicing purposes, the pivoting providing access to the other tray.

The tray body 41 defines fiber entryways 80, 82, 84 and 86. The entryways 80 and 82 can be used for routing fibers from a cable entering the closure onto the tray 40, so that splices of pairs of the fibers can be secured to the tray 40. The entryways 84 and 86 can be used to route fibers from the tray 40 to another tray in the stack of trays, thereby separating tray to tray fiber routings from cable to tray fiber routings.

The fiber management surface 48 is substantially trapezoidal. More specifically, the wall(s) defining the outer perimeter of the fiber management surface 48 include four straight portions and four curved portions alternating with the straight portions about the perimeter, one of the straight portions including both walls 66.

Due to the substantially trapezoidal shape of the fiber management surface 48, the wall 64 includes straight wall portions 88, 90 that run straight along axes 92 and 94, respectively. The axes 92 and 94 form acute angles 96, 98, respectively with the hinge axis 76. As shown in FIG. 9, the angles 96 and 98 span portions of the tray 40 and tray body 41.

Projecting from the walls 64 and 66 and other interior structures of the tray body 41, are fiber retaining lips 100. The lips 100 project from the walls 64, 66 parallel to the fiber management surface 48 and are configured to retain fibers between the fiber lips 100 and the fiber management surface 48.

The tray 40 includes a fiber looping region 102 and fiber working regions 104 and 106. The fiber looping region 102 is positioned generally between the two fiber working regions 104 and 106 relative to the axis 54.

The fiber looping region 102 includes structures 112 projecting from the fiber management surface 48 that define an inner routing and storage region 113. The structures 112 are configured to retain loops or partial loops of optical fibers about inner surfaces 114 of the structures 112 within the region 113.

In addition, the region 113 can be used to reverse the routing direction of fibers on the fiber management surface 48. Depending on the positioning of the cables entering the closure whose fibers are managed on the tray 40, 240 (FIGS. 18-20) relative to the positioning to the trays 40, 240 in the closure, it can be more efficient or otherwise desirable to route all of the fibers onto the tray 40, 240 through only one side of the tray 40, 240.

With respect to the tray 40 specifically, for example, in one use embodiment, all fibers routed on the tray enter the tray through the entryway 80, and the routing direction of some of those fibers is reversed on the tray by routing them through the region 113 in order to line up the rerouted fibers for splices with others of the fibers. In another use embodiment, all fibers routed on the tray 40 enter the tray through the entryway 82, and the routing direction of some of those fibers is reversed on the tray by routing them through the region 113 (in the opposite direction as the previous embodiment) in order to line up the rerouted fibers for splices with others of the fibers. In another use embodiment, one half of the spliced fibers enter the tray via the entryway 80, and the other half of the spliced fibers enter the tray via the entryway 82, such that rerouting via the region 113 is not needed for proper alignment of fiber to fiber at the splice. Thus, the region 113, and the structures 112 can be used for fiber rerouting and/or for fiber slack storage and retention.

Non-spliced optical fibers can be stored in one or more loops or loop portions in the fiber looping region 102. In addition, the fiber looping region 102 can be used to retain slack of fibers that are spliced and whose splices are supported by the tray 40 in one of the fiber working regions 104, 106. In some examples, the structures 112 or other structures in the looping region 102 can be sized and configured to be fitted with a label that, e.g., indicates the fiber contents of the tray 40, the manufacturer, or the closure to which the tray belongs. Such labels can be applied in any suitable fashion, such as with a sticker or by writing.

To maximize the length of fibers that can be retained within the looping region 102, in some examples, the structures 112 are sized such that fiber loops retained by the surfaces 114 have radii that are less than or equal to one half the radii of fiber loops that retained by, and circumscribed by a triangle defined by the longitudinal axes of the walls 66, 108 and 110.

Each fiber working region 104, 106 includes mounting structures 120 for mounting fiber management components, such as splice holders, splitter holders, and adapters. Each mounting structure 120 includes a pair of side by side tapered openings 122 and 124, and a cantilever arm 126. Projections 128, 130 of a fiber management component, such as splice body holder block 140, are inserted towards the fiber management surface 48 into the openings 122, 124 causing the cantilever arm 126 to flex. The fiber management component is then slid laterally (parallel to the fiber management surface 48) such that the projections enter the tapered regions of the openings 122, 124 which releases the cantilever arm 126 to its relaxed position in which it blocks or inhibits lateral sliding of the projections out of the tapers and thereby acts as a retainer. Engagement of the projections and the tapered regions forms a dovetail connection between the fiber management component and the mounting structure 120. To remove the fiber management component, the cantilever arm 126 can be flexed again in the same direction (e.g., by hooking the eye 127 of the cantilever arm 126 and pulling away from the fiber management surface 48), allowing the projections of the fiber management component to be slid out of the tapered regions of the openings 122, 124.

In the depicted example tray 40, each fiber working region 104, 106 includes three of the mounting structures 120 arranged side by side. In other examples, more or fewer mounting structures (e.g., one, two, four, or more) can be arranged side by side in one or each of the workings regions 104, 106. When a block 140 is mounted to or intended to be mounted to a working region 104, 106, the region 104, 106 can also be described as a splice body holder block region.

A wall 108 projecting from the fiber management surface 48 on one side partially defines the working region 104 and a portion of the fiber looping region 102 on the opposite side. Likewise, a wall 110 projecting from the fiber management surface 48 on one side partially defines both the working region 104 and a portion of the fiber looping region 102. Lips 100 project from each wall 108, 110 to retain fibers in the fiber looping region 102.

Each splice body holder block 140 includes a body 142 that includes channels 144. In this example, each block 140 includes six channels 144. Each channel 144 defines a longitudinal channel axis 146 along an elongate dimension of the channel. Each channel 146 is configured to hold at least one protective body, each protective body supporting one or more splices. Latch arms 148 provided at each channel 144 can flex to receive and securely hold a splice protective body in the channel 144.

When the block 140 is mounted to the mounting structures 120 in the working region 104 or 106, each axis 146 is parallel to the corresponding axis 88, 90. That is, in this position, the axes 146 form an oblique, acute angle with the hinge axis 76. In addition, when mounted to the mounting structures 120 in the working region 104 or 106, the body 142 of the block 140 abuts the corresponding straight wall portions 88, 90. In addition, when mounted to the mounting structures 120 in the working region 104 or 106, the body 142 of the block 140 abuts the corresponding wall 108, 110.

The depicted mounting arrangement and orientation of the splice body holder blocks 140 on the tray body 41, in conjunction with one or more of the relative positioning, and/or sizing of the fiber looping region 102 defined by the tray body 41 can optimize one or more fiber management factors as described above. For example, the number of splices supported on the tray 40 can be increased while providing sufficient space for looping fibers without bending the fibers beyond acceptable minimum bend radii.

An example improvement in a fiber routing scheme made possible by the tray 40 is shown in FIG. 17. Referring to FIG. 17, an optimized routing and splicing scheme for optical fibers 160 and 162 on the tray 40 is shown. Portions of at least some of the fibers are stored in loops 166 in the looping region 102. At least some of the fibers 360 and 362 are spliced together and the protective bodies 164 of those splices are held by the blocks 140 mounted in the working regions 104, 106. 12 protective bodies 164 are supported by the blocks 140 in the regions 104, 106 and each protective body 164 supports one or more splices (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 or more splices), each splice being between a fiber 160 and a fiber 162. Ramped surfaces 172 and 174 extending from the wall 64 are symmetrical about the axis 42. The ramped surfaces 172 and 174 can facilitate fiber routing from the working regions 104 and 106, respectively, to the looping region 102. The ramped surfaces 172 and 174 can be curved to gently route fibers therealong.

Referring now to FIGS. 11-16, a fiber management tray 240 will be described. The tray 240 includes a tray body 241 that can be of unitary construction (e.g., from a single mold of material, such as a polymeric material). The tray 240 also includes one or more fiber management components that are selectively mounted to the tray body 241, such as splice body holder blocks (or splice chips) 140.

The tray body 241 has the same or substantially the same outer dimensions, shape, and size as the tray 24 and the tray body 41 described above in connection with FIGS. 3 and 6-10. That is, the outer shape and dimensions of the tray body 241 are optimized for the domed housing piece 12 of the closure 10 (FIG. 1) or another domed housing piece.

The tray 240 is configured to be stacked in a stack of the trays 240 with each tray pivotally mounted to a framework, in the same manner as described above in connection with the organizer assembly 18 (FIG. 3).

As with the tray 24 and the tray 40, the tray 240 is substantially trapezoidal in shape. The tray extends from a top 256 to a bottom 258 along a first axis 260. The tray extends along a second axis 242 from a proximal end 244 to a distal end246. The tray extends along a third axis 254 from a first side 250 to a second side 252. The axes 242,

254 and 260 are mutually perpendicular to one another. The axes 242 and 254 intersect each other at a point 262. The point 262 projects along the axis 260 onto the center C2 of the fiber management surface 248 of the tray 240. The center C2 is defined as the point on the fiber management surface 248 where two perpendicular dimensions of the fiber management surface 248 that are parallel to the axes 242 and 254, respectively, and aligned therewith parallel to the axis 260, intersect and are bisected.

The tray body 241 includes walls 264, 266 projecting away from the fiber management surface 248 parallel to the axis 260. The walls 264, 266 define an outer perimeter of the fiber management surface 248.

The tray body 241 includes a mounting portion 70. The mounting portion 70 includes hinge portions. The hinge portions include a squared hinge pin 72 and a hinge pegs 74 that are received in complementary mounting features of a tray support, such as the tray support plate 31 of the framework 20 (FIG. 3). When mounted to a tray support, the hinge portions of the tray body 241 form a hinge with the tray support, such that the tray body 241 can be pivoted relative to the tray support about a hinge axis 276 defined by the hinge portions of the tray body 241. In particular, one or more trays 240 in a stack of the trays mounted to the tray support can be pivoted away from another tray in the stack that is to be worked on, e.g., for fiber routing and/or splicing purposes, the pivoting providing access to the other tray.

The tray body 241 defines fiber entryways 280, 282, 284 and 286. The entryways 280 and 282 can be used for routing fibers from a cable entering the closure onto the tray

240, so that splices of pairs of the fibers can be secured to the tray 240. The entryways 284 and 286 can be used to route fibers from the tray 240 to another tray in the stack of trays, thereby separating tray to tray fiber routings from cable to tray fiber routings.

The fiber management surface 248 is substantially trapezoidal. More specifically, the wall(s) defining the outer perimeter of the fiber management surface 248 include four straight portions and four curved portions alternating with the straight portions about the perimeter of the fiber management surface 248, one of the straight portions including both walls 266.

Projecting from the walls 264 and 266 and other interior structures of the tray body

241, are fiber retaining lips 300. The lips 300 project from the walls 264, 266 parallel to the fiber management surface 248 and are configured to retain fibers between the fiber lips 300 and the fiber management surface 248.

The tray 240 includes a fiber looping region 302 and a fiber working region 304. The fiber looping region 302 fully surrounds the fiber working region 304.

The fiber looping region 302 includes structures 312, 314 projecting from the fiber management surface 248. The structures 312, 314 are configured to retain loops or partial loops of optical fibers about curved surfaces 313, 315 of the structures 312, 314, respectively. Non-spliced optical fibers can be stored in one or more loops or loop portions in the fiber looping region 302. In addition, the fiber looping region 302 can be used to retain slack of fibers that are spliced and whose splices are supported by the tray 240 in the fiber working region 304.

In some examples, the structures 312, 314 or other structures of the tray body 241 can be sized and configured to be fitted with a label that, e.g., indicates the fiber contents of the tray 240, the manufacturer, or the closure to which the tray belongs. Such labels can be applied in any suitable fashion, such as with a sticker or by writing. The working region 206 includes mounting structures 120 for mounting fiber management components, such as splice holders, splitter holders, and adapters. The mounting structures 120 function as described above in connection with the tray 40 and cooperate with splice body holder blocks 140 as described above (FIGS. 6-10). When blocks 140 are mounted to or intended to be mounted to the working region 304, the region 304 can also be described as a splice body holder block region.

In the depicted example tray 240, the working region 306 includes nine of the mounting structures 120 arranged side by side in a row parallel to the axis 254. In other examples, more or fewer mounting structures can be arranged side by side in the working region 304.

A surface 307 of a wall 308 projecting from the fiber management surface 248 on one side partially defines the working region 304 on one side of the working region 304, and a surface 309 of the wall 314 partially defines the working region 304 on the opposite side of the working region 304. The surfaces 307 and 309 are on opposite sides of the axis 242 and asymmetrically positioned about the axis 242.

In this example, the working region 304 is sized to mount three of the blocks 140 in a side-by-side abutting arrangement. Thus, the tray 240 can support at least 18 protective bodies of one or more splices, each in a dedicated channel 144 of a block 140. When mounted to the mounting structures 120 in the working region 304, each axis 146 is non-parallel (in the depicted embodiment, each axis 146 is perpendicular) to the hinge axis 276. In addition, when mounted to the mounting structures 120 in the working region 304, the body 142a of one of the blocks 140 abuts the surface 307 and the body 142b of another of the blocks 140 abuts the surface 309, with the third block 140 positioned between these two blocks.

Advantageously, the region 304 includes the center C2 of the fiber management surface 248. Further advantageously, the center C3 of the region 304, C3 being a point on the fiber management surface 248, is offset along the axis 254 from the center C2 of the fiber management surface 248. The center C3 is not offset from the center C2 relative to the axis 242.

Further advantageously, the tray body 241 is asymmetrical about the axis 242, in that the positioning and configuration of the walls 312 and 308 are not mirror images of the wall 314 about the axis 242. Due to this asymmetry, a cross-channel 370 can be, and is, provided. The cross-channel 370 is a curved channel (e.g., an S-shaped channel) defined by opposing inner surfaces 391, 393, respectively, of the walls 308 and 312, which serve as fiber routing structures. The cross-channel 370 is configured for reversing routing direction of one or more optical fibers on the fiber management surface 248. For example, if all fibers enter the tray 240 from the same entryway, the routing of some of the fibers can be reversed by passing them through the cross channel 370, allowing the reversed fibers to be spliced to non-reversed fibers and having their splices supported in the working region 304.

The depicted mounting arrangement and orientation of the splice body holder blocks 140 on the tray body 241 can optimize one or more fiber management factors as described above. For example, the number of splices supported on the tray 240 can be increased while providing sufficient space for looping fibers without bending the fibers beyond acceptable minimum bend radii, and providing sufficient space and structures for reversing routing directions of fibers without over-bending them. The depicted arrangement and orientation of the blocks 140 on the tray body 241 includes but is not limited to any one or more of the offset nature of the centers C2 and C3, and/or coverage of the center C2 by the blocks 140 with channels 144 that are oriented non-parallel (e.g., perpendicular to) the hinge axis 276

Similarly, the depicted asymmetrical arrangement of structures 308, 312 and 314 about the axis 242 can optimize one or more fiber management factors as described above. For example, the number of splices supported on the tray 240 can be increased while providing sufficient space for looping fibers without bending the fibers beyond acceptable minimum bend radii, and providing sufficient space and structures for reversing routing directions of fibers without over-bending them.

Example improvements in fiber routing schemes made possible by the tray 240 are shown in FIGS. 18-20.

Referring to FIG. 18, an optimized routing and splicing scheme for optical fibers 360 and 362 on the tray 240 is shown. The fibers 360 and 362 enter the tray 240 through opposite entryways. Portions of at least some of the fibers are stored in loops 366 in the looping region 302. At least some of the fibers 360 and 362 are spliced together and the protective bodies 364 of those splices are held by the blocks 140 mounted in the working region 304. 18 protective bodies 364 are supported by the blocks 140 in the region 304, and each protective body 364 supports one or more splices (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 or more splices), each splice being between a fiber 360 and a fiber 362. As shown in FIG. 18, none of the fibers 360 are routed through the cross channel 370.

Referring to FIG. 19, a further optimized routing and splicing scheme for optical fibers 460 on the tray 240 is shown. The fibers 460 all enter the tray through a single entryway nearer the side 250 and nearer the cross channel 370. Portions of at least some of the fibers 560 are stored in loops 466 in the looping region 302. At least some pairs of the fibers 460 are spliced to each other and the protective bodies 464 of those splices are held by the blocks 140 mounted in the working region 304. 18 protective bodies 464 are supported by the blocks 140 in the region 304, and each protective body 464 supports one or more splices (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 or more splices), each splice being between two of the fibers 460. Because all of the fibers 460 enter through the same entryway, the routing direction of some of the fibers 460 must be reversed on the fiber management surface by routing portions 460a of those fibers through the cross channel 370 as shown, and then continuing the routing of those fibers to the blocks 140. As shown, the routing of the portions 460a via the cross channel 370 is a substantially S-shaped path. The channel 370 is contoured to enable the substantially S-shaped path.

Referring to FIG. 20, a further optimized routing and splicing scheme for optical fibers 560 on the tray 240 is shown. The fibers 560 all enter the tray through a single entryway nearer the aide 252 (opposite the entryway where the fibers 460 enter in FIG.

19) and farther from the cross channel 370 than the entryway used by the fibers 460 in FIG. 19. Portions of at least some of the fibers 560 are stored in loops 566 in the looping region 302. At least some pairs of the fibers 560 are spliced to each other and the protective bodies 564 of those splices are held by the blocks 140 mounted in the working region 304. 18 protective bodies 564 are supported by the blocks 140 in the region 304, and each protective body 564 supports one or more splices (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 or more splices), each splice being between two of the fibers 560. Because all of the fibers 560 enter through the same entryway, the routing direction of some of the fibers 560 must be reversed on the fiber management surface by routing portions 560a of those fibers through the cross channel 370 as shown, and then continuing the routing of those fibers to the blocks 140. As shown, the routing of the portions 560a via the cross channel 370 is a substantially S-shaped path, with the image of the substantially S-shaped path being flipped as compared with the corresponding substantially S-shaped path of the fiber portions 460a of FIG. 19. The channel 370 is contoured to enable the substantially S- shaped path.

Having described the preferred aspects and embodiments of the present disclosure, modifications and equivalents of the disclosed concepts may readily occur to one skilled in the art. However, it is intended that such modifications and equivalents be included within the scope of the claims which are appended hereto.

Claims

WHAT IS CLAIMED IS:

1. An optical fiber management tray, comprising: a hinge portion configured to pivotally mount the tray to a tray support about a hinge axis defined by the hinge portion; a fiber management surface; and a wall projecting away from the fiber management surface and defining at least a portion of an outer perimeter of the fiber management surface, the wall including a straight wall portion that extends along a wall axis that is oblique to the hinge axis; and a mounting structure configured to mount a splice body holder block to the fiber management surface, the splice body holder block including a channel for receiving a splice body, the channel defining a longitudinal axis, the mounting structure being positioned to mount the splice body holder block to the fiber management surface such that the longitudinal axis is parallel to the wall axis.

2. The optical fiber management tray of claim 1, wherein the mounting structure is positioned to mount the splice body holder block to the fiber management surface such that the splice body holder block abuts the wall portion.

3. The optical fiber management tray of any of claims 1-2, wherein the hinge axis and the wall axis define an acute angle that spans a portion of the tray.

4. The optical fiber management tray of any of claims 1-3, further comprising the splice body holder block.

5. The optical fiber management tray of claim 4, wherein the splice body holder block is mounted to the mounting structure.

6. An optical fiber management tray extending from a proximal end to a distal end, comprising: a mounting portion positioned at the proximal end and configured to pivotally mount the tray to a tray support; a fiber management surface; and at least one wall projecting away from the fiber management surface and defining at least a portion of an outer perimeter of the fiber management surface, the at least one wall including, at opposite sides of the fiber management surface, straight wall portions that extend along wall axes that converge toward each either as they extend toward the distal end; and mounting structures configured to mount one or more splice body holder blocks to the fiber management surface, each splice body holder block including channels for receiving splice bodies, the channels defining longitudinal axes, the mounting structures being positioned to mount each splice body holder block such that each splice body holder block abuts one of the straight wall portions and such that the longitudinal axes are parallel to one of the wall axes.

7. An optical fiber management tray, comprising: a hinge portion configured to pivotally mount the tray to a tray support about a hinge axis defined by the hinge portion; a fiber management surface including a splice body holder block region, the region including mounting structures configured to mount one or more splice body holder blocks to the fiber management surface at the region such that the one or more splice body holder blocks cover a center of the fiber management surface, the splice body holder block including a channel for receiving a splice body, the channel defining a longitudinal axis, the mounting structures being positioned to mount the one or more splice body holder blocks to the fiber management surface such that the longitudinal axis is non-parallel to the hinge axis.

8. The optical fiber management tray of claim 7, further comprising fiber routing structures projecting from the fiber management surface and partially defining the splice body holder block region, wherein the fiber routing structures are positioned and configured to form an asymmetry in the tray about a central axis defined by the tray and perpendicular to the hinge axis.

9. The optical fiber management tray of claim 8, wherein the fiber routing structures are unitarily formed with the fiber management surface.

10. An optical fiber management tray, comprising: a tray body, including: a hinge portion configured to pivotally mount the tray to a tray support about a hinge axis defined by the hinge portion; a fiber management surface including a splice body holder block region, the region including mounting structures configured to mount one or more splice body holder blocks to the fiber management surface at the region; and fiber routing structures projecting from the fiber management surface and partially defining the splice body holder block region, wherein the fiber routing structures are positioned and configured such that the tray body is asymmetrical about a central axis defined by the tray body and perpendicular to the hinge axis.

11. The optical fiber management tray of claim 10, wherein the fiber routing structures are unitarily formed with the fiber management surface.

12. The optical fiber management tray of any of claims 7-9, wherein the mounting structures are positioned to mount the one or more splice body holder blocks to the fiber management surface such that the longitudinal axis is perpendicular to the hinge axis.

13. The optical fiber management tray of any of claims 7-12, wherein a center of the splice body holder block region is offset from the center of the fiber management surface.

14. The optical fiber management tray of any of claims 7-13, further comprising a cross channel for reversing a routing direction of a fiber on the fiber management surface.

15. The optical fiber management tray of claim 14, wherein the cross channel is defined between two cross channel routing structures projecting from the fiber management surface.

16. The optical fiber management tray of claim 15, wherein one of the cross channel routing structures abuts, and partially defines, the splice body holder block region.

17. The optical fiber management tray of any of claims 7-16, further comprising at least one wall projecting away from the fiber management surface and defining at least a portion of an outer perimeter of the fiber management surface, the wall including two straight wall portions that extend along wall axes that are oblique to the hinge axis, wherein the hinge axis and each of the wall axes define an acute angle that spans a portion of the tray.

18. The optical fiber management tray of any of claims 6-17, further comprising one or more splice body holder blocks.

19. The optical fiber management tray of claim 18, wherein the one or more splice body holder blocks are mounted to the mounting structures.

20. The optical fiber management tray of claim 19, wherein each splice body holder block is configured to support at least 12 protective splice bodies.

21. The optical fiber management tray of any of claims 8 or 10, further comprising one or more splice body holder blocks mounted to the mounting structures, each splice body holder block being configured to support at least 18 protective splice bodies.

22. The optical fiber management tray of any of claims 1-20, further comprising a structure for looping fibers, the structure projecting away from the fiber management surface.

23. The optical fiber management tray of any of claims 1-22, further comprising fiber retaining lips configured to retain optical fibers between the fiber retaining lips and the fiber management surface.

24. The optical fiber management tray of any of claims 1-23, wherein each mounting structure includes a pair of side by side tapered openings and a cantilever arm.

25. An assembly, comprising: the optical fiber management tray of any of claims 1-24; and the tray support, the optical fiber management tray being pivotally coupled to the tray support.

26. A fiber optic closure, comprising: housing pieces configured to cooperate to form a sealable and re-enterable interior closure volume; an optical fiber management tray according to any of claims 1-24; and the tray support positioned in the interior closure volume, the tray being pivotally mounted to the tray support.

27. The fiber optic closure of claim 26, wherein the optical fiber management assembly includes a plurality of the fiber management trays according to any of claims 1- 24 pivotally mounted to the tray support.

28. The fiber optic closure of any of claims 26-27, wherein one of the housing pieces includes a dome cover defining a longitudinal axis.

29. The closure of claim 28, wherein the dome cover defines a substantially circular cross-section perpendicular to the longitudinal axis of the dome cover.

30. A method, comprising: routing optical fibers onto the support surface of the optical fiber management tray according to any of claims 7 or 10 through one or more entryways defined by the fiber management tray positioned at only one side of the hinge portion; routing portions of at least one of the optical fibers through the cross channel; and routing the at least one of the optical fibers to a splice body holder block mounted to the fiber management surface and holding one or more splice bodies containing one or more splices including ends of the at least one and not more than half of the optical fibers.

31. The method of claim 30, further comprising forming a loop of at least one of the optical fibers, the loop being supported by the optical fiber management surface and fully surrounding the splice body holder block.

32. A method, comprising: routing first optical fibers onto the support surface of the optical fiber management tray according to any of claims 7-17 through a first entryway defined by the fiber management tray positioned at a first side of the hinge portion; routing second optical fibers onto the support surface of the optical fiber management tray through a second entryway defined by the fiber management tray positioned at second side of the hinge portion that is opposite the first side; and routing the first optical fibers and the second optical fibers to a splice body holder block mounted to the fiber management surface and holding splice bodies each containing a splice that includes an end of one of the first fibers and an end of one of the second fibers, wherein none of the first optical fibers and second optical fibers are routed through the cross channel.

33. The method of claim 32, further comprising forming a loop of at least one of the optical fibers, the loop being supported by the optical fiber management surface and fully surrounding the splice body holder block.