U.S. patent application number 11/690898 was filed with the patent office on 2008-05-08 for self-curling sleeve.
Invention is credited to Angela L. Baer.
Application Number | 20080105324 11/690898 |
Document ID | / |
Family ID | 35787699 |
Filed Date | 2008-05-08 |
United States Patent
Application |
20080105324 |
Kind Code |
A1 |
Baer; Angela L. |
May 8, 2008 |
SELF-CURLING SLEEVE
Abstract
A substrate including a plurality of monofilaments, or a
combination of monofilaments and multi-filament yarns oriented in
perpendicular directions, has a tendency to curl around a central
space. When all monofilaments are used, the monofilaments along one
direction may have a larger diameter than the monofilaments along
the other direction. The monofilaments are woven such that the
larger diameter monofilaments form floats predominantly on one side
of the substrate. For the monofilament-multifilament combination
the monofilaments form floats predominantly on one side of the
substrate. The substrate curls about an axis parallel to the
monofilaments forming the floats. The side having the floats faces
outwardly away form the central space. Preferably, the
monofilaments are orientated in the warp direction along the
substrate. The filaments may be woven in a herringbone twill weave,
a double cloth herringbone twill weave or a satin weave to provide
the floats.
Inventors: |
Baer; Angela L.;
(Westminster, MD) |
Correspondence
Address: |
Robert L. Steams;Dickinson Wright PLLC
38525 Woodward Avenue
Bloomfield Hills
MI
48304-5092
US
|
Family ID: |
35787699 |
Appl. No.: |
11/690898 |
Filed: |
March 26, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11185589 |
Jul 20, 2005 |
7216678 |
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11690898 |
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60589270 |
Jul 20, 2004 |
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60657847 |
Mar 2, 2005 |
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Current U.S.
Class: |
139/386 |
Current CPC
Class: |
D03D 3/08 20130101; D03D
17/00 20130101; F16L 57/06 20130101; D03D 13/004 20130101; H02G
15/18 20130101; F16L 59/10 20130101; H02G 3/0462 20130101 |
Class at
Publication: |
139/386 |
International
Class: |
D03D 3/00 20060101
D03D003/00 |
Claims
1. A self-curling sleeve for protecting elongate members received
in a central space of said sleeve, said sleeve comprising: a
substrate fabricated of a plurality of interlocked yarns and having
a pair of free edges extending along a length of said sleeve, said
interlocked yarns including at least one monofilament exerting a
bias force causing said substrate to self-curl about said central
space.
Description
RELATED APPLICATIONS
[0001] This application is a divisional of priority application
U.S. Patent Application Ser. No. 11/185,589, filed Jul. 20,
2005.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
[0002] None
TECHNICAL FIELD
[0003] This invention concerns sleeves for receiving and protecting
elongated items, such as wiring harnesses.
BACKGROUND OF THE INVENTION
[0004] Protective sleeving is used throughout the automotive,
marine and aerospace industries to organize and protect elongated
items, such as wiring harnesses and optical fiber cables. The
sleeving surrounds the elongated items and protects them against
cuts, abrasion, radiant heat, vibration induced wear and other
harsh environmental threats. When positioned within protective
sleeving, the wiring or cables are also held together in a neat
bundle, allowing a multiplicity of different items to be handled
like a sub-assembly, thus saving time and effort during integration
of the items into a product.
[0005] Protective sleeving may be made by weaving filaments into a
substrate and then resiliently biasing the substrate into a tubular
form to define a central space for receiving the elongated items.
Biasing may be effected by various means appropriate to the types
of yarns used to make the substrate. Polymer filaments may be
biased by heating them when the substrate is wrapped about a
cylindrical mandrel, the filaments taking a permanent set
conforming to the shape of the mandrel. Filaments can also be
resiliently biased into a curved shape by chemical means as well as
by cold working.
[0006] When substrates are biased into a tubular shape,
monofilaments are typically oriented in the "hoop" or
circumferential direction of the tube. Monofilaments provide
excellent stiffness and strong resilient biasing that maintains the
substrate in the tubular shape and tens to restore the substrate to
this shape in the absence of distorting forces such as occur when
the sleeve is manipulated to insert or remove an elongated
item.
[0007] A significant disadvantage associated with sleeves that are
biased into a tubular shape is that the biasing is effected by a
separate step in the process of making the sleeve. The filaments
comprising the sleeve may be biased by cold working before weaving
or may be biased after weaving by heating the substrate when
wrapped about a mandrel, but these actions constitute a separate
step that adds to the cost and the time required to produce the
sleeve. It would be advantageous to provide a sleeve formed from a
substrate that is self-curling and needs no separate step to effect
resilient biasing of the filaments into the tubular shape.
SUMMARY OF THE INVENTION
[0008] The invention concerns a self-curling sleeve for receiving
and protecting elongated items. The sleeve comprises a substrate
woven from a plurality of monofilaments or a combination of
monofilaments and multi-filament yarns. When all monofilaments are
used, the monofilaments along one direction may have a larger
diameter tan the monofilaments along the other direction. For the
combination embodiment, the monofilaments are oriented along a
first direction and the multifilament yarns are oriented along a
second direction substantially perpendicular to the first
direction. The monofilaments are woven such that the larger
diameter monofilaments form floats predominantly on one side of the
substrate. For the monofilament-multifilament combination the
monofilaments form floats predominantly on one side of the
substrate. The substrate curls about an axis parallel to the
monofilaments forming the floats to define and surround a central
space. The side having the floats faces outwardly away from the
central space. In a certain embodiment, the longitudinal floats
face outwardly, and the horizontal floats face inwardly.
[0009] Relatively more rigid filaments are preferably located in
the warp direction, and relatively less rigid filaments are
preferably located in the weft direction. Preferably, the
monofilament yarns are oriented in the warp direction along the
substrate. For the combination of monofilaments and multifilaments,
the monofilaments are preferably oriented in the warp
direction.
[0010] The filaments may be woven in a herringbone twill weave, a
double cloth herringbone twill weave or a satin weave to provide
the floats.
[0011] These and other features and advantages of this invention
will become more apparent to those skilled in the art from the
detailed description of a preferred embodiment. The drawings that
accompany the detailed description are described below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The present invention will now be described by way of
example with reference to the following drawings in which:
[0013] FIG. 1 is a perspective view of a self-curling sleeve
according to the invention;
[0014] FIG. 2 is a perspective view of a self-curling sleeve
according to the invention;
[0015] FIG. 3 is a perspective view of a filling faced
substrate;
[0016] FIGS. 4-10 are schematic diagrams describing weave patterns
used for the self-curling sleeve according to the invention;
[0017] FIG. 11 is a perspective view of another embodiment of a
self-curling sleeve;
[0018] FIGS. 12-14 are schematic diagrams describing weave patterns
used for the self-curling sleeve according to the invention;
and
[0019] FIG. 15 is a perspective view of another embodiment of the
self-curling sleeve according to the invention, and corresponding
to the weave pattern of FIG. 14.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
[0020] FIG. 1 shows a self-curling sleeve 10 according to the
invention. Sleeve 10 comprises a substrate 12 woven from a
plurality of monofilaments 14 and multifilament yarns 16. The
monofilaments 14 are oriented in a first direction, shown by arrow
18, and the multifilament yarns 16 are oriented in a second
direction, substantially perpendicular to the first direction, and
indicated by arrow 20. Preferably, the monofilaments 14 are
oriented in the warp direction of the substrate and the
multifilament yarns are oriented in the weft direction and
constitute the "fill yarns" or "picks" of the weave.
[0021] Preferred weave patterns for weaving the substrate 12 are
those such as twills and satin weaves that form "floats"
predominantly on one side of the substrate. As shown in FIG. 2, a
"float" 22 is formed when a filament or yarn, such as monofilament
14, crosses over more than one filament or yarn oriented
perpendicular to it, such as weft yarns 16. The substrate is called
"warp faced" when woven with a predominance of warp yarn floats on
the surface of the substrate, as illustrated in FIG. 2. A "filling
faced" substrate, where filling yarn floats 24 predominate on the
surface of the fabric is shown in FIG. 3.
[0022] As shown in FIG. 1, the substrate 12, whether warp-faced or
filling faced, when woven with monofilaments 14 in the warp
direction and multifilament yarns 16 in the weft direction,
exhibits a pronounced tendency to curl about an axis 26
substantially parallel to the monofilaments 14. The direction of
curl is away form the surface having the floats 22, i.e., the
substrate 12 naturally curls about axis 26 such that the floats 22
formed by the monofilaments 14 are on what becomes the outside
surface 28 of the sleeve 10. Upon curling, the substrate 12 takes
on a tubular shape and defines a central space 30 for receiving the
elongated items.
[0023] The reason for the curling of this exemplary substrate 12 is
thought to arise from at least two factors. First, the relatively
stiff members (e.g., monofilaments 14) are oriented in the warp
direction, while the more flexible and pliant members (e.g.,
multifilament yarns 16) are oriented in the weft direction.
Accordingly, it has been found that the sleeve is self-curling when
the filamentary members in the warp direction have greater beam
strength than those in the weft.
[0024] With reference to the embodiment of FIG. 1, monofilaments in
the warp direction stiffen the substrate 12 along he longitudinal
axis 26, provide rigidity to the sleeve 10 and resist bending. In
contrast, the more flexible multifilament yarns 16, oriented in the
weft direction, are pliant and bend easily to allow the substrate
12 to curl about axis 26, the bending axis for the multifilament
weft yarns 16. Multifilament yarns having deniers from about 200 to
about 2000 are feasible.
[0025] The second factor causing substrate curling is related to
the floats 22 which are thought to generate the forces that induce
the substrate to curl. As noted above, the substrate 12 curls away
form the surface 28 having floats 22. The substrate 12 is
unbalanced in the sense that one surface is different from the
other in that on one surface floats 22 predominate. This surface
imbalance causes internal stresses throughout the substrate which
cumulatively manifest themselves in a curvature of the substrate
about axis 26.
[0026] It is further thought that the repeating chevron pattern
that is apparent in herringbone twill weaves adds to the strength
of the curl, because it is observed that substrates woven in warp
and weft faced herringbone twill patterns show a greater tendency
to curl than substrates formed from satin weaves. Although the
satin weaves have floats, they do not display the chevron pattern
associated with the herringbone twill and do not manifest the
curling tendency to the same degree as the herringbone twill
substrates.
[0027] FIGS. 4-10 illustrate various weave patterns that form
substrates that curl when the warp members comprise monofilaments
14 and the weft members comprise multifilament yarns 16. Because it
is difficult to clearly illustrate the actual woven substrate,
weave patterns are preferably schematically illustrated using a
matrix. The matrix represents a repeating weave pattern. The
columns of the matrix represent the warp members and the rows
represent the fill or weft members. Each square of the matrix
represents the member that appears on the upper surface of the
fabric as woven on the loom. An "X" in a square represents a
cross-over point at which the corresponding warp member crosses
over a corresponding weft or filling member. The upper surface is
not necessarily the outer surface of the sleeve 10, as that will be
determined by on which side the floats predominate.
[0028] FIGS. 4 and 5 represent simple herringbone twill patterns,
FIG. 4 being filling faced and FIG. 5 being warp faced. Both of
these weave patterns produce substrates having a relatively strong
tendency to curl about the warp axis.
[0029] FIGS. 6 and 7 are more complex herring bone weaves in that
they differ from FIG. 4 and 5 at columns 4 and 8 where there are
four extra warp cross-overs on the surface for the filling faced
pattern (FIG. 6) or two extra weft cross-overs for the warp faced
pattern (FIG. 7) as well as a greater frequency of the repeated
pattern. Substrate woven with this pattern tend to show weaker
tendency to curl than the simple herringbone patterns of FIGS. 4
and 5.
[0030] FIG. 8 shows a satin weave. Substrates woven from this
pattern show a weaker tendency to curl than the complex herringbone
pattern of FIGS. 6 and 7. Note that the chevron pattern
characteristic of the herringbone weave is largely absent from the
satin weave shown in FIG. 8.
[0031] Bar far, the strongest tendency to curl is manifest in
substrates woven according to the herringbone double cloth pattern
shown in FIG. 9. Double cloth is a compound fabric in which a face
cloth and a back cloth, each with its own warp and filling, are
combined during weaving. Although the aforementioned chevron
pattern is not readily visible in FIG. 9, which shows the double
cloth weave, when shown as fabric comprising the double cloth, as
in FIG. 10, the chevron pattern of the fabrics is clearly
manifest.
[0032] Preferred materials for both the monofilaments and
multifilament yarns include synthetic polymers such as polyester,
polypropylene and aramids such as Kevlar and nylon. It is also
feasible to use materials such as stainless steel, nitinol, elgiloy
or other resilient metals having a high yield stress, preferably
for the warp monofilaments.
[0033] Self-curling substrates according to the invention provide a
sleeve that takes a tubular shape without the need for a separate
biasing step. Such sleeves may be used to unsheathe elongated items
and may rely on their inherent resilient biasing to contain the
items within a central space, or closing means, such as tape, may
be used as a wrap to further secure the sleeve. The sleeve may also
be outfitted with other closure means, such as lacing, hook and
loop fasteners, buttons, zippers and the like which allow easy
application and removal of the sleeve to a substrate.
[0034] Another embodiment of a self-curling sleeve 32 according to
the invention is shown in FIG. 11. Self-curling sleeve 32 comprises
a substrate 12 woven from monofilaments 34 that extend in the warp
direction 18 and monofilaments 36 that extend in the weft direction
20.
[0035] As described for the previous embodiment having both
monofilaments and multifilament yarns, substrate 12 can be induced
to curl about an axis 26 through the use of a twill or satin weave
pattern that creates an imbalance between the surfaces of the
substrate. Again, warp faced or filling faced substrates are
advantageous.
[0036] The strength and degree of curl can be further augmented by
appropriate choice of the monofilaments 34 and 36 comprising the
substrate 12. For example, to induce or augment the curl about axis
26 when it is oriented in the warp direction 18, monofilaments 34,
oriented parallel to the warp direction 18, are chosen that have a
larger diameter than the monofilaments 36 oriented in the fill
direction 20. The larger diameter monofilaments 34 have a greater
area moment of inertia than the smaller diameter monofilaments 36
and, for filaments having the same elastic modulus, have greater
bending stiffness. The less stiff monofilaments 36 bend more easily
and thus allow the substrate to curl around the axis 26 due to the
imbalance engendered by the floats. Monofilaments having diameters
between about 0.001 inches to about 0.020 inches provide practical
filaments for forming self-curling sleeves according to the
invention. Practical examples have been made which exhibit strong
curling force. Some examples include a substrate comprising warp
monofilaments made of polyphenylene sulfide (PPS) and having a
diameter of about 0.010 inches woven with dual (side by side) PPS
fill monofilaments having a diameter of about 0.008 inches. In
another example, warp monofilaments of polyester having a diameter
of about 0.010 inches were woven with polyester fill monofilaments
having a diameter of about 0.006 inches.
[0037] It is also possible to augment or control the curling
through varying the material of the monofilaments used it he warp
direction as compared with that of the fill direction. Varying the
material allows the designer to vary the modulus of elasticity of
the monofilament. By using material having a higher or lower
elastic modulus in monofilaments extending in one direction or the
other, the curling tendency can be augmented or reduced, and fine
tuning of the curl can be achieve in conjunction with the weave
pattern and the relative diameter of the monofilaments. For
example, to increase the curl about the warp axis, fill
monofilaments having a relatively lower modulus would be used to
make the fill monofilaments more flexible than the warp
monofilaments. Similarly, if it were desired to weaken the curling
tendency about the warp axis, fill monofilaments having a greater
modulus would be used.
[0038] Many materials are feasible for use as monofilaments in
self-curling sleeves according to the invention. The materials
include poly(ethylene terephthalate) PET, a type of polyester),
nylon 6 and nylon 6,6, silver coated nylon, olefins, aramids such
as Nomex.RTM., which is a registered trademark of E.I. du Pont de
Nemours and Company of Wilmington, Del., and Kevlar.RTM., which is
a registered trademark of E. I. du Pont de Nemours and Company of
Wilmington, Del., poly(ether ether ketone) (PEEK), modacrylic,
glass fibers, carbon fibers, acrylic fibers, spandex, rayon,
acetate, poly(lactic acid) PLA), poly (ethylene naphthalate) (PEN,
a type of polyester), melamine (Basofil.RTM., which is a registered
trademark of BASF Aktiengesellschaft of Germany), fluorocarbons, as
well as natural fibers such as cotton.
[0039] A further feature is the addition of heat to the sleeve. For
certain materials the application of heat will induce further
curling and also provide a thermosetting action that will hold the
sleeve in its further curled configuration.
[0040] FIG. 12 shows a weave pattern matrix that schematically
depicts a twill weave. The twill weave shown is characterized by
the chevron pattern of the warp monofilament cross-over points
being oriented in the fill direction. The cross-over points are
indicated by the "X" at various intersection of warp and fill
monofilaments. Note again, the columns represent the warp
monofilaments and the rows represent the fill monofilaments. The
chevron pattern is not continued to the edge of the substrate
(columns 11 and 12) where a basket weave is introduced to produce a
clean edge.
[0041] FIG. 13 describes a twill weave wherein the chevron pattern
is oriented along the warp direction.
[0042] FIG. 14 illustrates yet another practical curl inducing
weave pattern wherein the warp monofilament cross over points,
indicated by the "X" symbols running diagonally to both the warp
and fill directions of the substrate. This pattern produces a
self-curling sleeve embodiment 38 as sown in FIG. 15, wherein the
substrate 40 curls into a helix 42 around the longitudinal axis 44
of the sleeve. The monofilaments comprising the warp elements 46
and fill elements 48 of the sleeve are oriented at an angle to the
axis 44. It is further noted that the weave patterns illustrated in
any of the diagrams in FIGS. 4-10 and 12-14 may be used with any
combination of monofilament or monofilament-multifilament forming a
substrate.
[0043] Although examples of woven substrates are provided, it is
also recognized that self-curling sleeves can also be made through
weft insertion of filaments during warp knitting, or also by warp
knitting alone, to produce the imbalance necessary to induce the
substrate to curl.
[0044] The foregoing invention has been described in accordance
with the relevant legal standards, thus the description is
exemplary rather than limiting in nature. Variations and
modifications to the disclosed embodiment may become apparent to
those skilled in the art and do come within the scope of the
invention. Accordingly, the scope of legal protection afforded this
invention can only be determined by studying the following
claims.
* * * * *