U.S. patent application number 11/757023 was filed with the patent office on 2008-12-04 for apparatus and method for managing flexible lines.
Invention is credited to Peter Richard Baxter, James L. Cairns, Srikanth Ramasubramanian.
Application Number | 20080296426 11/757023 |
Document ID | / |
Family ID | 40087025 |
Filed Date | 2008-12-04 |
United States Patent
Application |
20080296426 |
Kind Code |
A1 |
Cairns; James L. ; et
al. |
December 4, 2008 |
APPARATUS AND METHOD FOR MANAGING FLEXIBLE LINES
Abstract
An apparatus for managing flexible lines has first and second
spool members secured together by a hinge which allows the spool
members to be folded between an open condition in which the spool
members are in co-planar, side-by-side positions and a folded,
closed condition in which the spool members are folded towards one
another until they are aligned and substantially face-to-face. Each
spool member has a groove extending in an at least substantially
continuous loop which receives successive windings of a line or
strip as it is wound in a figure eight pattern between the two
spool members in an open condition. When winding is complete, the
spool members can be folded together into the folded, closed
condition.
Inventors: |
Cairns; James L.; (Ormond
Beach, FL) ; Ramasubramanian; Srikanth; (Daytona
Beach, FL) ; Baxter; Peter Richard; (Ormond Beach,
FL) |
Correspondence
Address: |
PROCOPIO, CORY, HARGREAVES & SAVITCH LLP
530 B STREET, SUITE 2100
SAN DIEGO
CA
92101
US
|
Family ID: |
40087025 |
Appl. No.: |
11/757023 |
Filed: |
June 1, 2007 |
Current U.S.
Class: |
242/157R |
Current CPC
Class: |
B65H 75/06 20130101;
B65H 2701/32 20130101; G02B 6/4457 20130101 |
Class at
Publication: |
242/157.R |
International
Class: |
B65H 57/12 20060101
B65H057/12 |
Claims
1. An apparatus for managing flexible lines, comprising: a folding
device having a first spool member, a second spool member, and a
hinge connecting the spool members, each spool member having
opposite first and second faces and an outer peripheral edge; the
hinge allowing the spool members to be folded between an open
condition in which the spool members are in co-planar, side-by-side
positions and a closed, folded condition in which the spool members
are folded towards one another about the hinge into a substantially
aligned, face-to-face position, the first faces of the spool
members facing one another in the folded condition; and each spool
member having a winding groove extending in an at least
substantially continuous loop which receives successive windings of
a line as it is wound in a figure eight pattern between the two
spool members with the folding device in an open condition, wherein
the windings form a folded figure eight in the folded, closed
condition of the device.
2. The apparatus of claim 1, wherein each winding groove extends
around at least a major part of the outer peripheral edge of the
respective spool member and has first and second spaced rims.
3. The apparatus of claim 2, wherein the hinge comprises a pair of
spaced hinge portions with a gap between the hinge portions forming
a cross over area for line passing from one spool member to the
other spool member.
4. The apparatus of claim 3, wherein the first rim of the groove on
each spool member terminates at each end of the gap between the
hinge portions to leave the groove open along one side across the
gap.
5. The apparatus of claim 1, wherein the hinge connects the first
faces of the spool members.
6. The apparatus of claim 1, wherein each spool member is a flat
member and each winding groove is located on the second face of the
spool member and spaced inwardly from the outer peripheral edge of
the spool member.
7. The apparatus of claim 6, wherein each spool member is a flat,
ring-shaped member having a central opening.
8. The apparatus of claim 6, wherein the hinge comprises two spaced
hinge portions with a gap between the hinge portions providing a
cross over area for line wound from one spool member to the
other.
9. The apparatus of claim 8, wherein each spool member has a cut
out extending from the peripheral edge to the groove in an area
between the hinge portions and facing the cross over area, each cut
out providing a pathway for line extending between a respective
groove and the cross over area.
10. The apparatus of claim 1, wherein the hinge is formed
integrally with the spool members.
11. The apparatus of claim 1, wherein the hinge and spool members
are separate elements, and a fastener mechanism connects the hinge
to each spool member.
12. The apparatus of claim 1, wherein each spool member has at
least one opening which is aligned with the opening in the other
spool member in the folded, closed condition of the folding device,
the openings receiving a holding device which secures windings of
line in the respective winding groove.
13. The apparatus of claim 1, further comprising a mounting device
which holds at least one folding device in the folded
condition.
14. The apparatus as claimed in claim 13, wherein each spool member
has a central opening and the central openings are aligned in the
folded, closed condition of the folding device, and the mounting
device comprises a mounting base and a hub extending from one face
of the base which extends through the aligned openings.
15. The apparatus as claimed in claim 14, wherein the hub has
resilient fingers which are compressed as the folding device is
pushed over the hub, the fingers having a recess which receives the
folding device in a storage position.
16. The apparatus as claimed in claim 1, wherein each winding
groove is of generally rectangular cross-section.
17. The apparatus as claimed in claim 1, wherein each winding
groove has an inner end, opposite side walls, and an outer opening,
and is of generally triangular cross-section with the opposite side
walls tapering inwardly towards one another from the inner end to
the outer opening of the groove.
18. A method for managing slack in a flexible line extending
between two points on the line, comprising: positioning a folding
device with first and second spool members which are secured
together by a hinge in a side-by-side, coplanar and open condition;
winding a length of a line in a first direction around a first
winding groove in the first spool member, extending the line over a
cross over area between the spool members, winding a subsequent
length of the line in a second direction around a second winding
groove in the second spool member, and extending the line over the
cross over area between the spool members to form a figure eight;
repeating the preceding winding steps to form successive figure
eights until the majority of the slack in the line is taken up by
the windings on the spool members; and folding the spool members
together about the hinge into a folded, closed condition, whereby a
folded figure eight is formed.
19. The method of claim 18, wherein each winding groove extends
around the outer peripheral edge of the respective spool
member.
20. The method of claim 18, wherein each winding groove is located
on one face of the respective spool member and spaced inwardly from
the peripheral edge of the spool member.
21. The method of claim 18, wherein the spool members are folded
such that each winding groove is located on the outermost face of
the respective spool member in the folded, closed condition.
22. The method of claim 18, wherein the step of winding the line in
a first direction about the first winding groove in the first spool
member comprises first engaging a portion of the line in part of
the second winding groove adjacent the cross over area and
extending the line from the second winding groove over the cross
over area and into the first winding groove before winding the line
in the first direction about the first winding groove.
23. The method of claim 18, wherein the winding steps are repeated
until a length of the line corresponding to at least one turn
remains unwound, and the spool members are folded together before
winding a final turn of the line onto one of the spool members.
24. The method of claim 18, wherein the flexible line comprises one
or more optical fibers.
25. The method of claim 24, further comprising adjusting the
lengths L.sub.1 and L.sub.2 of two fiber pigtails so that the total
fiber length L=L.sub.1+L.sub.2=l.sub.1+l.sub.2+n.pi.d+.epsilon.,
where d is the diameter of each winding groove, n is an integer,
l.sub.1 and l.sub.2 are the distances from the fiber points on each
side of the folded spool members to the point where fiber joins the
respective winding groove in the folded, closed position, and E is
a compensation factor based on variation in winding diameter as a
result of plural turns of the fiber being wound on top of one
another, and subsequently splicing the adjusted fiber pigtails
together prior to winding onto the first and second spool members
in the figure eight pattern.
Description
BACKGROUND
[0001] 1. Field of the Invention
[0002] The present invention relates to an apparatus and method for
managing flexible lines or flexible elongate elements such as a
wire, tube, individual fiber, ribbon fiber, or cable with fixed
ends.
[0003] 2. Related Art
[0004] When terminating optical connectors or other devices to
optical fiber cables, it is necessary to splice the optical fibers
together. Since excess fiber length is needed to perform fusion
splicing, an excess of fiber is left between the devices after
splicing. The excess fiber length has to be managed. Since both
ends of the fiber are fixed or inaccessible, coiling the fiber is
difficult and potentially damaging due to the torque which builds
up with each loop. Fiber is also susceptible to optical measurement
losses or shortened life if it is wound to a radius smaller than
the minimum fiber bend radius. It is known to wind fiber in a
figure eight pattern, relieving the torque as you wind first in one
direction then in the other. One known fiber management system is
two spaced, coplanar spools between the fixed fiber ends. Fiber is
wound in a figure eight pattern on the spools, while maintaining a
radius greater than the minimum fiber bend radius. The two
side-by-side spools take up additional space between the optical
devices.
[0005] Similar problems are encountered in managing lengths of
other lines such as flexible wires or tubes with fixed ends.
Coiling such lines can also be difficult due to torque build
up.
[0006] Therefore, what is needed is an apparatus and method that
reduces or overcomes these significant problems found in the known
systems as described above.
SUMMARY
[0007] Embodiments described herein provide for an apparatus and
method for managing flexible lines or flexible elongate elements
between fixed ends or points in the line to handle any slack in the
line between the fixed ends.
[0008] According to one aspect, apparatus for managing flexible
lines is provided, which comprises a folding device having first
spool member, a second spool member, and a flexible or foldable
joint or hinge connecting the spool members which allows the spool
members to be folded between an open condition in which the spool
members are in co-planar, side by side positions and a closed,
folded condition in which the spool members are folded towards one
another about the joint until they are aligned and substantially
face-to-face, each spool member having a groove extending in an at
least substantially continuous loop which receives successive
windings of a line or elongate element as it is wound in a figure
eight pattern between the two spool members with the device in an
open condition.
[0009] In a first embodiment, each spool member has opposite first
and second faces and an outwardly facing winding channel or groove
extending around at least a major part of the peripheral edge of
the spool member, the hinge extending between the first faces of
the spool members which are directed inwardly when the spool is
folded, whereby the annular channels are located on the outside of
the folded spool assembly in the folded condition. The spool
members may have central openings which are aligned in the folded
condition. In a second, alternative embodiment, each spool member
is a flat, ring-shaped member having opposite first and second
faces and a winding groove on the first face for receiving windings
of a flexible line or flexible elongate element. In the second
embodiment, the winding grooves are arranged to face outwardly in
the folded flat condition.
[0010] The apparatus may be used to manage any type of flexible
elongate line or element, such as optical fibers, electrical wires,
cables, ropes, flexible tubes or hoses, threads, or the like, with
suitable adjustment of the winding groove width and diameter on
each spool. The material of the spool may also be varied, depending
on the material of elongate line to be managed. In one embodiment,
the flexible elongate elements comprise one or more individual
optical fibers or ribbon fibers. Although parts of the following
description refer to individual or ribbon fibers as the flexible
line or elongate element, other types of flexible elongate element
may also be managed in an equivalent manner to that described
below. Where the flexible line is optical fiber, the first
embodiment above is suitable for managing one or more individual
fibers or for managing ribbon fiber. The second embodiment may be
used to for managing a thinner elongate element such as an
individual optical fiber.
[0011] In one embodiment, a fiber management apparatus is provided
in which the hinge comprises two spaced hinge portions connecting
the spool members with a gap between the hinge portions providing a
cross over area for windings of fiber from one spool member to the
other. The annular winding channels or grooves may have cut-outs
aligned with the gap. The gap or cross over area provides a
clearance for fiber or other flexible line in the cross over area
when the fiber is wound in a figure eight pattern with the device
in an open condition, allowing the fiber to bend at the cross over
area while the device is folded. Fiber is wound first in one
direction around the first spool, then extended over the gap onto
the second spool, and wound in the opposite direction around the
second spool before extending over the gap and crossing over the
previous length of fiber in the gap, then back onto the first
spool, where it is wound again in the first winding direction. This
process is repeated until most of the slack is taken up, at which
point the two spool members are folded together about the hinge
portions into the folded, closed condition. Any remaining free
fiber is then wound into the appropriate spool member. In the first
embodiment of the apparatus, the inner faces of the spool members
face one another and the wound fibers are outside the folded faces.
The channels in which the fibers are wound are outside the hinge in
the folded condition and fibers in the gap or cross over area tend
to be held away from the opposing inner faces of the spool member
as the devices is folded. If the device were folded with the
winding channels on the inside of the fold, there is a greater risk
of fibers in the cross over area contacting the spool members
during folding.
[0012] In both the first and second embodiments of the apparatus,
the hinge portions may be formed integrally with the spool members
or may be formed separately and then secured to the respective
spool members by any suitable fastener mechanism. Holes may be
provided in opposite rims of each spool member to receive tie wrap
for keeping wound fiber in place on the spool member. The tie wrap
can also extend between the spool members so as to secure the spool
members in the folded condition.
[0013] In another embodiment, the apparatus further comprises a
mounting device for holding one or more folding devices in the
folded condition. In one embodiment, the folding device has a
central opening in the folded condition and the mounting device
comprises a mounting base and a hub extending from one face of the
base which extends through the opening in at least one folding
device in the folded condition. The hub may have flexible fingers
which are compressed as the folding device is pushed over the hub,
and which have an indent to receive one or more folding devices in
a storage position in which the fingers spring back to hold the
device on the hub. The mounting base may be mounted on any suitable
structure within a dedicated enclosure for the fiber or other
flexible lines or flexible elongate elements.
[0014] In the case of optical fiber management, the mounting base
may be attached to one or more stand off rods between optical
devices into which the optical fibers extend.
[0015] According to another aspect, a method of managing excess
length of a flexible line or elongate element between fixed points
on the line is provided, which comprises positioning first and
second spool members which are connected together by a hinge in a
coplanar, open condition, winding a length of the line in a first
direction around a groove in the first spool member, extending the
line over a cross over area between the spool members, winding a
subsequent length of the line in a second direction around a groove
in the second spool member, extending the line back over the
cross-over area between the spool members to form a figure eight
pattern, repeating the preceding winding steps to form successive
figure eights until at least a major part of the excess length of
line is taken up by the windings on the spool members, and folding
the spool members together about the hinge into a folded, closed
condition. In one embodiment, the spool members are folded before a
final winding is made, and the final winding is made about the
appropriate groove after the spool members are folded together. In
one embodiment, the flexible line may be one or more individual
optical fibers or an optical ribbon fiber.
[0016] Other features and advantages of the present invention will
become more readily apparent to those of ordinary skill in the art
after reviewing the following detailed description and accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The details of the present invention, both as to its
structure and operation, may be gleaned in part by study of the
accompanying drawings, in which like reference numerals refer to
like parts, and in which:
[0018] FIG. 1 is a perspective view of a prior art fiber management
apparatus positioned between two fiber optic devices;
[0019] FIG. 2A is a perspective view of one embodiment of a fiber
management apparatus comprising a folding dual spool device, with
the device in an open condition;
[0020] FIG. 2B is a perspective view of the device of FIG. 2A in a
partially folded condition;
[0021] FIG. 2C is a perspective view of the device of FIGS. 2A and
2B in a more folded condition;
[0022] FIG. 2D is a perspective view of the device of FIGS. 2A to
2C in a completely folded, closed condition;
[0023] FIG. 3 is a schematic perspective view of the device of
FIGS. 2A to 2D in the open condition of FIG. 2A which schematically
indicates the winding of fiber on the two spools of the folding
device with the fiber shown outside the winding grooves for
illustration purposes;
[0024] FIG. 4A is a front elevation view of the device of FIGS. 2
and 3 in a folded, closed condition with fiber wound on the
device;
[0025] FIG. 4B is a cross-sectional view illustrating a modified
dual spool folding device in the position of FIG. 4A, illustrating
a modified winding groove or channel shape;
[0026] FIG. 5 is a perspective view illustrating one embodiment of
a fiber management apparatus comprising a folding dual spool device
as in FIGS. 2 to 4A and a mounting device for the folding dual
spool device of FIGS. 2 to 4A, with the dual spool device in the
closed position of FIG. 2D and positioned in alignment with the
mounting device.
[0027] FIG. 6 is a perspective view similar to FIG. 5 illustrating
several folding dual spool devices positioned on the mounting
device;
[0028] FIG. 7 is a perspective view illustrating the apparatus of
FIGS. 5 and 6 positioned between two optical devices;
[0029] FIG. 8A is a perspective view illustrating another
embodiment of a fiber management apparatus comprising a modified
folding dual spool device in an open condition;
[0030] FIG. 8B is a perspective view of the device of FIG. 8A in a
partially folded condition;
[0031] FIG. 9 is a perspective view of the device of FIGS. 8A and
8B in the open condition illustrating fiber wound on and between
the spools in a figure eight pattern;
[0032] FIG. 10 is a front elevation view of the device of FIGS. 8
and 9 in a folded, closed position with fiber wound on the device;
and
[0033] FIG. 11 is a schematic front elevation view of the fiber
management apparatus of FIGS. 2 to 7 positioned between two fixed
fiber points at two optical devices, illustrating parameters for
calculating a desired total spliced fiber length prior to splicing
and winding of the fiber.
DETAILED DESCRIPTION
[0034] Certain embodiments as disclosed herein provide for an
apparatus and method for managing flexible lines or flexible
elongate elements having fixed ends. For example, one apparatus and
method as disclosed herein allows for managing excess of fiber
between fixed ends or points on the fiber produced when terminating
various devices to optical fiber cables.
[0035] After reading this description it will become apparent to
one skilled in the art how to implement the invention in various
alternative embodiments and alternative applications. However,
although various embodiments of the present invention are described
herein, it is understood that these embodiments are presented by
way of example only, and not limitation. As such, this detailed
description of various alternative embodiments should not be
construed to limit the scope or breadth of the present invention as
set forth in the appended claims.
[0036] In the following description, embodiments of an apparatus
and method for managing fibers such as optical fibers are
described, but the described apparatus and methods may
alternatively be used for managing other types of flexible line or
flexible elongate elements, such as electrical or other flexible
wires, cables, ropes, flexible tubes or hoses, threads, or the
like. In the case of optical fiber, the fiber may be one or more
individual optical fibers or a ribbonized fiber (ribbon fiber).
Ribbon fiber contains multiple fibers in a ribbon-like form. The
management apparatus and methods for flexible elongate elements or
lines other than fibers may be identical to those described in the
embodiments below, with appropriate adjustment of the scale and
material of the apparatus to accommodate flexible elongate elements
of different sizes and materials.
[0037] The term "spool" as used in this application means a device
on which a flexible elongate element can be wound or spooled.
Although the spools illustrated in the drawings and described below
are round, in other embodiments the spools may have other
continuous loop shapes such as elliptical, oval, polygonal, or the
like.
[0038] The term "hinge" as used in this application means a
flexible or foldable joint or connection that allows the turning or
pivoting of a part, and may be a so-called "living hinge" of
bendable material which is sufficiently flexible to allow pivoting,
or a physical pivot or hinge joint.
[0039] FIG. 1 illustrates a prior art fiber management apparatus 10
comprising two spools 12,13 positioned in a side-by-side, coplanar
arrangement and secured to a stand-off rod 14 between two fiber
optic devices 16,18 such as a connector shell and a cable
termination housing. Excess of fiber, after the fiber pigtails from
each device have been spliced, is managed by winding in a figure
eight pattern around the two spools 12, 13. It can be seen that
this arrangement takes up a significant amount of space.
[0040] FIGS. 2 to 4 illustrate a first embodiment of a fiber
management apparatus comprising a folding dual spool device 20,
with FIGS. 2A to 2D illustrating steps in folding the device 20
between an open condition (FIG. 2A) and a folded, closed condition
(FIG. 2D). Device 20 comprises first and second spool members 22,
24 connected together by a hinge comprising two spaced hinge
portions 25, 26. In the illustrated embodiment, the hinge portions
are formed integrally with the two spool members and may comprise
flexible hinges for folding and unfolding the device. In this case,
the entire device is formed integrally out of a material which is
flexible when sufficiently thin, such as plastic, and the hinges
are formed by reduced thickness portions or indents in the material
which can bend, i.e. so-called "living hinges". However, in
alternative embodiments, a separate hinge may be provided and
suitably fastened or connected between the two spool members. In
either case, the hinge comprises spaced hinge portions 25, 26 with
a gap or space 28 between the hinge portions. The hinge portions
25, 26 form a central fold line about which the spool members can
be folded.
[0041] Each spool member is generally ring-shaped or annular with a
central opening 30, a first or inner face 32, a second or outer
face 34, and a winding channel or groove 35 running around its
outer peripheral edge between spaced inner and outer rims 36, 38.
As illustrated in FIG. 2C, the inner rim 36 is cut out or
eliminated at region 39 in the space 28 between the two hinge
portions 25, 26, so that the winding channel or groove is open on
one side in this space to allow for fiber crossover and bending as
the device is folded, as described in more detail below in
connection with FIG. 4. The first face 32 has an annular ledge 41
which extends inwardly beyond the winding groove and has an inner
peripheral edge 31 which surrounds opening 30. Two diametrically
opposed keys or projections 40, 42 are provided in the inner
peripheral edge of the annular ledge 41. A series of spaced
openings 44 are provided around ledge 41 of each spool member.
[0042] The hinge portions or living hinges 25, 26 allow the dual
spool device 20 to be folded between an open condition as
illustrated in FIG. 2A in which the spool members 22,24 are in
spaced, side-by-side and coplanar positions, and a closed, folded
condition as illustrated in FIG. 2D, in which the inner faces 32 of
each spool member face inwardly and are aligned face-to-face, as
indicated in FIG. 2D, with the keys 40,42 and openings 44 in each
annular ledge 41 aligned. As can be seen in FIG. 2D, the winding
channels or grooves 35 are on the outside of the hinge when the
device is folded.
[0043] In order to wind a length of one or more individual fibers
or ribbon fibers 45 between points 46, 47 of the fiber onto device
20, as illustrated schematically in FIG. 3, the device is first
positioned in the fully open condition. In practice, when optical
fiber is to be managed, the points 46 and 47 are locations where
the fiber or fibers extend out of respective devices to be
connected together, and may be fixed or unfixed. The spliced length
of fiber 45 between these points is the slack which is to be
managed by the fiber management apparatus or device 20. The
windings or turns of fiber are shown outside the winding grooves in
FIG. 3 for clarity in understanding the winding method, but in
practice these turns will be made in the grooves. A first turn of
the fiber 45 is made in a first direction in the direction of
arrows A1, A2, A3 about the spool member 24, with the winding
direction as indicated by the arrows being anti-clockwise as viewed
in FIG. 3. The fiber is then crossed over from the spool member 24
to the spool member 22 in the gap or cross over area 28 between the
two hinge portions 25, 26, and enters the winding groove 35 in the
other spool member 22. A second turn of the fiber is then made
about the spool member 22 in the direction of arrows B1, B2, B3,
which is clockwise as viewed in FIG. 3. At this point, depending on
the length of fiber remaining, the fiber may cross over the first
length of fiber in cross over area 28 at cross over point 50 and
another turn may be made in a clockwise direction about the winding
groove in spool member 24 followed by another turn around the
winding groove in spool member 22. This figure eight winding
pattern results in cancellation of twist in the fiber which would
have resulted from one turn on the spool. If an even number of
turns is made before the slack is taken up, there is substantially
no twist remaining in the fiber. If an odd number of total turns is
made, there is approximately one half turn of twist in the fiber.
The device is folded into the closed, folded condition before the
final winding so as to reduce the risk of accidental damage or
fiber breakage on a fixed end during folding.
[0044] FIG. 4A illustrates the device 20 in the folded, closed
condition after the final winding has been made. As illustrated,
the gap 28 between the hinge portions and the elimination of the
inner rim 36 of each spool along edge 39 between the hinge portions
allows for the fiber cross over at point 50 and also allows the
fiber to bend freely in the cross over area as the device 20 is
folded.
[0045] FIG. 4B illustrates a modification of the device 20 in which
the winding channels or grooves 135 are of a different shape to the
winding grooves 35 of the embodiment of FIGS. 2 to 4A. As
illustrated in FIG. 4A, winding grooves 35 are of generally
rectangular cross section and uniform width. In FIG. 4B, the
winding groove 135 is of generally hourglass or triangular
cross-sectional shape from its inner end to its outer end, leaving
a small, slit-like opening 136 which helps in locating individual
fibers or ribbon fibers as they are fed into the groove, and also
helps to hold fibers in the groove.
[0046] As illustrated in FIG. 2D, the openings 44 in the two spool
members 22, 24 are aligned when the device is in the folded
condition. Tie wraps, clips, or other holding devices may be
engaged in each aligned pair of openings in this condition and
extend over the winding grooves to hold the wound fiber in place,
and also to hold the folding device closed. When fiber has been
wound in a figure eight pattern and the device is folded into the
closed condition, a folded figure eight is formed. This takes up
only around half of the storage space of an extended or flat figure
eight as in the prior art apparatus of FIG. 1.
[0047] The width and depth of the winding channels or grooves 35 is
dependent on the thickness of fiber, fibers, or other elongate
flexible elements to be wound on device 20. The device may be used
for managing an individual fiber, multiple individual fiber
circuits between optical devices to be connected, or a ribbon
fiber. In alternative embodiments, device 20 may be used for
managing other types of flexible elongate elements in the manner
illustrated in FIGS. 2 to 4B, such as electrical wires or cables,
steel wires and ropes as used in the construction and elevator
industry, hoses such as hydraulic or pneumatic fluid carrying
hoses, threads of wool, nylon, and the like as used in the textile
industry, and others. The dimensions and material of device 20 may
be suitably adjusted based on the thickness and the likely length
of the flexible elongate element to be managed. In the case of
optical fiber, fibers, or ribbon fibers, the winding groove of each
spool member has a radius which is equal to or greater than the
fiber minimum bend radius.
[0048] The fiber management apparatus may also comprise a mounting
device for holding one or more of the folding dual spool devices 20
of FIGS. 2 to 4B. FIG. 5 illustrates one embodiment of a mounting
device 55 for holding one or more of the folding devices 20 in the
closed, folded condition with fiber wound onto the spools in a
figure eight pattern as in FIGS. 3 and 4A. In FIG. 5, a folded dual
spool device 20 is shown aligned with device 55 prior to mounting
on the device. The mounting device in this embodiment comprises a
base 56 having a projecting hub 58 for extending through the
central opening 30 in the folded device 20. The mounting hub 58
comprises a four-finger collet having four flexible fingers 60
arranged to grip against the central opening in the spool, with
gaps or keyways 62 between each adjacent pair of fingers. A greater
or lesser number of fingers may be provided in alternative
embodiments. A mounting recess 64 is provided on the outer surface
of each finger 60.
[0049] As illustrated in FIG. 5, the folded spool device 20 is
positioned with opening 30 aligned with hub 58 and keys 40, 42
aligned with keyways 62, and the central opening 30 is then moved
over the hub. The keys 40, 42 engage in the keyways 62 between
adjacent fingers of the hub 58 to restrict rotation of the spool
device 20. The fingers 60 are urged inwardly as the device 20 is
forced over the outer regions of the fingers, and then spring
outwardly to grip against the inner edge 31 of the opening 30 when
the folding device is aligned and seated on the mounting recess 64.
As illustrated in FIG. 6, more than one folding device 20 may be
mounted on the hub 58 where multiple ribbon fibers or bunches of
fibers are to be managed. FIG. 6 illustrates a stack of three
folding devices 20 mounted on the mounting device 55. A greater or
lesser number of folding devices may be accommodated with suitable
adjustment of the length of hub 58.
[0050] The base 56 of the mounting device 58 may have a mounting
arrangement for engagement with stand-off rods 14 between two
optical devices 16, 18, as illustrated in FIG. 7. In the
illustrated embodiment, the base 56 has one or more through bores
65 for engagement over stand off rods 14, as seen in FIGS. 5 to 7.
Other types of stand-off rod engagement mechanisms may be used in
alternative embodiments, such as grooves in the rear face of base
56, or an attachment clip or the like. It can be seen by comparison
of the prior art fiber management apparatus of FIG. 1 with the
fiber management apparatus in FIG. 7 that the amount of space
needed to manage the fibers is substantially halved with the
folding figure eight storage pattern of this embodiment. In FIG. 7,
each folding device may store spooled fibers of multiple individual
circuits or a multiple circuit ribbon fiber.
[0051] A slimmer version of the folding device 20 may be used for
managing a single or individual fiber in a single optical circuit.
In this alternative, the winding channel or groove 35 in each spool
is much narrower than in FIG. 4, with the width not much greater
than that of a single fiber. This allows a much greater number of
folding devices 20 to be mounted in a stacked arrangement on
mounting device 55 or other mounting devices for this purpose.
Where each fiber is spooled or managed on its own dedicated folding
device, troubleshooting of a circuit can be done by removing the
fiber for that circuit from the folding device holding that fiber,
without unwinding fibers on other folding devices. In FIGS. 1 to 7,
the first and second rims 36, 38 of the folding device are of the
same outer diameter. In one embodiment of a slimmer folding device,
the second rim 38 which is outermost in the folded condition may be
of smaller diameter than the first rim 36, since there is only one
fiber wound in the groove 35 in this embodiment, and thus the
groove does not have to be as deep in order to contain the fiber
windings.
[0052] FIGS. 8A, 8B, 9 and 10 illustrate another embodiment of a
fiber management apparatus comprising a modified folding dual spool
device 70. One or more dual spool devices 70 may also be mounted on
mounting device 55 after folding, like the devices 20 of the first
embodiment, as discussed in more detail below. Dual spool device 70
has a pair of flat, ring-shaped members or spool members 72, 74
connected by spaced hinge portions 75, 76. A gap or cross over area
78 is located between the hinge portions, as in the previous
embodiments. In device 70, a winding channel or groove 80 is
provided in a first or outer face of each spool member, rather than
an outwardly facing winding channel or groove at a peripheral edge
of a spool, as in the embodiments described above in connection
with FIGS. 1 to 7. Each winding channel or groove 80 is spaced
inwardly from the outer peripheral edge of the respective ring or
spool member. The grooves 80 are provided in the face of each ring
member which is outermost when the device is folded into a closed,
folded condition.
[0053] FIGS. 8A and 9 illustrate the device 70 in an open
condition. Each ring member has a cut-out in the gap or cross over
area 78 between hinge portions 75 and 76 which extends up to the
groove 80. This means that the groove terminates at each end of the
cross over area 78, so that fiber can enter and exit the grooves 80
when leaving or entering the cross over area or gap 78. A pair of
fiber entry/exit grooves 83 are also provided on the outer face of
each ring member, each extending tangentially in opposite
directions from the winding groove 80 to the outer peripheral edge
82 of the ring member.
[0054] Each ring member has a central opening 84 and an inner
peripheral edge 85. A pair of diametrically opposed keys or
projections 86 project inwardly towards one another from the inner
peripheral edge 85. These keys have the same purpose as the keys
40, 42 in the previous embodiment, i.e. for alignment and
anti-rotation purposes when the folding device 70 is folded and
mounted on a hub 58 of a mounting device 55. A series of spaced
openings 88 are provided around each ring member in the space
between the winding groove 80 and the inner peripheral edge 85. As
in the previous embodiments, the openings 88 may be used for ties,
clips, or the like to hold wound fiber on the device 70, and also
to hold the device in the closed, folded condition of FIG. 10.
[0055] As noted above, FIGS. 8A and 9 illustrated the folding
device 70 in the flat, open condition. In this condition, a length
of an individual fiber 90 or other narrow wire or line extending
between points 92, 94 may be wound onto the two spools in the
manner generally illustrated in FIG. 9. Starting from end 92, a
first turn of the fiber may first enter the channel or groove 80 in
ring member 72 through a selected entry groove 83, extend a short
distance around that groove, then pass across the gap or cross over
area 78 to enter the groove 80 in the second ring member 74,
extending in an anti-clockwise direction for one turn in groove 80
before crossing over the first turn at a cross-over point 95 in gap
78 (see arrows A1, A2, A3 and A4). The fiber is then wound in a
clockwise direction around groove 80 in ring member 72 (see arrows
B1, B2), and may either exit the spool via groove 83, or may
continue back onto the ring member 74 in the same path A1, A2, A3,
A4, dependent on the amount of fiber to be wound onto device 70.
The provision of four entry/exit grooves allows the fiber to enter
and exit the device at the most convenient location, dependent on
the length of fiber to be wound or spooled onto the device.
[0056] When a majority of the length of fiber has been wound onto
device 70, and there is only a turn or less of fiber left to be
wound, device may be folded from the open condition of FIG. 9 to
the closed, folded condition of FIG. 10. FIG. 8B illustrates an
intermediate, partially folded position of the device during
folding. The hinge portions 75, 76 are designed to fold in the
direction illustrated in FIG. 8B, with the face of each ring member
72, 74 which has no winding groove facing inwardly and the wound
fiber on the outside of the folded device. The cross over area or
gap 78 between the hinge members allows the fiber to bend easily.
Once the device is folded into a closed, folded condition with the
two ring members 72, 74 face to face, any remaining length of the
fiber can be wound around the appropriate winding groove to take up
substantially all the remaining slack in the fiber. The two ring
members can be secured together in the folded condition by passing
suitable ties, clips or the like through some or all of the aligned
openings 88.
[0057] The device 70 has a slimmer profile when folded than the
fiber management device of FIGS. 1 to 4, as can be seen by
comparing FIG. 10 with FIG. 4. One or more of the folding devices
70 of FIGS. 8 to 10 can be engaged on the hub of mounting device 55
in a similar manner to the folding fiber management devices 20 of
the first embodiment, with the aligned central openings engaging
over the fingers and the keys 86 engaging in the keyways 62 between
adjacent fingers. Several of the folding devices 70 may be used to
spool individual fibers and then mounted in a stack on the hub 58
of a mounting device 55 after folding into the closed condition of
FIG. 10, and the mounting device can then be mounted in the space
between the optical devices from which the fibers extend, as
described above in connection with the first embodiment.
[0058] The folding device 20 of the first embodiment above may be
used for handling or spooling lengths of multiple individual
fibers, ribbon fibers, or other elongate lines when the ends of the
lines are not accessible. In the case of optical fibers, a length
of one or more individual fibers or ribbon fiber typically projects
from an exit end of an optical device to be connected in line with
other optical devices, such as an optical or hybrid device housing
and an optical or hybrid cable. These lengths of optical fiber are
commonly known as pigtails, and the pigtail length is made
sufficient to allow for splicing on fusion splicing equipment. The
fiber pigtail may be an individual fiber, a bunch of individual
fibers, or one or more ribbon fibers which contain multiple fibers
in a ribbon-like form. The folding device 70 of FIGS. 8 to 10 is
intended for use in managing a single fiber, wire or other thin
flexible line, while folding device 20 may be used to manage an
individual fiber, plural individual fibers, or one or more ribbon
fibers. In either case, the length of pigtails to be connected
together prior to winding on devices 20 or 70 may be adjusted prior
to splicing so that the overall length of the spliced fiber or line
is equal to substantially a whole number of turns on the device,
while still providing a sufficient length for splicing purposes.
This adjustment can reduce the amount of slack in the spliced fiber
after winding onto the folding fiber management device.
[0059] A method of adjusting the length of fiber to be managed so
that it is close to a whole number of turns on the device 20 is
described below, with reference to FIG. I 1. A similar method is
used to adjust the length of fiber when it is to be wound on device
70. As noted above, a fiber pigtail of one or more individual
fibers or ribbon fiber normally extends from a housing or enclosure
for an optical fiber device such as an optical connector shell or a
cable termination housing before the device is connected to another
such device in an assembly.
[0060] In FIG. 11, the length L.sub.1 is the pigtail length from
the fixed point or end of one of the fibers or ribbon fibers at a
first device, the length L.sub.2 is the pigtail length from the
fixed point or end of the other fiber or ribbon fiber at a second
device, d is the diameter of the winding channel or groove on each
spool of device 20, and l.sub.1 and l.sub.2 are the distances on
each side of the folding device 20 from the fibers' fixed points to
the points where the spliced fiber joins the respective winding
channel or groove 35, typically at the apex or uppermost region of
the spool. Prior to splicing, a total spliced fiber length L is
calculated as follows:
L=L.sub.1+L.sub.2=l.sub.1+l.sub.2+n.pi.d+.epsilon., where
.epsilon.<<<d is a small additional length to compensate
for fiber buildup on the winding grooves with successive fiber
windings, and n is an integer corresponding to a number of turns on
dual spool device 20. Using this relationship, the installer can
calculate total spliced fiber lengths L corresponding to
substantially a whole number of turns on the two fiber winding
grooves, so that only a small amount of excess fiber is left after
winding in the figure eight pattern as described above. The integer
n may be an even or odd number. Where n is an odd number, there is
one half turn of twist left after winding on the spools. After
calculating the length L, the pigtails can then be cut to
appropriate lengths. The length L.sub.1 and the length L.sub.2 may
be different as long as the total of these lengths meets the above
relationship, and the installer can appropriately adjust these
lengths based on the available pigtail lengths on each side.
[0061] In the event of fiber damage after a splice, a section of
length q.pi.d, where q is an integer, which spans the damaged
portion may be removed or cut out before re-splicing. If possible,
depending on the length of the damaged portion, q is equal to one
so as to minimize the discarded fiber. This means that the fiber
length after splicing is still approximately equal to a whole
number of turns on the fiber winding grooves.
[0062] The above embodiments allow fibers, ribbon fibers, or other
flexible elongate elements or lines to be managed in a figure eight
pattern on dual spools with windings on each spool being in
opposite directions to cancel or reduce twist. At the same time,
the hinge between the spools allows the spools to be folded along a
central fold or hinge line into a folded, closed condition, to take
up approximately half the space of the fully extended dual spools.
The winding grooves are located outside the hinge on folding,
reducing the risk of fiber in the cross over area contacting a
spool member during folding into the closed condition.
[0063] The above description of the disclosed embodiments is
provided to enable any person skilled in the art to make or use the
invention. Various modifications to these embodiments will be
readily apparent to those skilled in the art, and the generic
principles described herein can be applied to other embodiments
without departing from the spirit or scope of the invention. Thus,
it is to be understood that the description and drawings presented
herein represent a presently preferred embodiment of the invention
and are therefore representative of the subject matter which is
broadly contemplated by the present invention. It is further
understood that the scope of the present invention fully
encompasses other embodiments that may become obvious to those
skilled in the art and that the scope of the present invention is
accordingly limited by nothing other than the appended claims.
* * * * *