(12) United States Patent
`Smith et al.
`
`(10) Patent No.:
`(45) Date of Patent:
`
`US 7.923,641 B2
`Apr. 12, 2011
`
`USOO7923641B2
`
`(54) COMMUNICATION CABLE COMPRISING
`SHIELDING MATERAL
`
`ELECTRICALLY SOLATED PATCHES OF
`
`(75) Inventors: Delton C. Smith, Greenwood, SC (US);
`R Si NRW.I. SS
`sts opher McNutt, Woodstock,
`
`(*) Notice:
`
`(73) Assignee: Superior Essex Communications LLP.
`Atlanta, GA (US)
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) bV 112 davs.
`(b) by
`y
`(21) Appl. No.: 12/313,914
`
`(22) Filed:
`(65)
`
`Nov. 25, 2008
`O
`O
`Prior Publication Data
`US 2009/0173511 A1
`Jul. 9, 2009
`O
`O
`Related U.S. Application Data
`(63) Continuation-in-part of application No. 1 1/502.777,
`filed on Aug. 11, 2006, now abandoned.
`
`6,770,819 B2 ck
`
`8, 2004 Patel .
`
`.
`
`.
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`.
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`.
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`.
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`.
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`.
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`.
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`.
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`.
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`.
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`.
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`.
`
`.
`
`.
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`.
`
`.
`
`.
`
`.
`
`. 174,113 R
`
`l
`$23, R 23. St.
`ylvia et al.
`6,850,161 B1
`2/2005 Elliott
`7,173,189 B1* 2/2007 Hazy et al. ................ 174/110 R
`7,332,676 B2
`2/2008 Sparrowhawk
`7,335,837 B2
`2/2008 Pfeiler et al.
`2006,0048961 A1
`3/2006 Pfeiler et al.
`2007/0037419 A1* 2/2007 Sparrowhawk ................. 439/98
`FOREIGN PATENT DOCUMENTS
`WO WO 2006/105166 A2
`5, 2006
`OTHER PUBLICATIONS
`“Product Catalogue” 2 pgs. Enterprise Cabling R&M, May 2006.
`“Draka' 12 pgs. Draka Comteq, Cable Solutions, Data cables, Sep.
`27, 2006.
`"10 Gigabit Ethernet Solutions' 8 pgs. R&M Convincing Cabling
`Solutions.
`Wetzikon, “R&M: The Rising Stars in Copper Cabling' 2 pgs. Sep.
`1, 2005.
`“R&M Star Real 10” 2 pgs. Mar. 2006.
`“Connections 29' 36 pgs. Sep. 2005.
`
`k .
`
`cited by examiner
`Primary Examiner — Chau N Nguyen
`(74) Attorney, Agent, or Firm — King & Spalding
`
`ABSTRACT
`(57)
`A tape can comprise a two-sided strip of dielectric material,
`(51) Int. Cl.
`with patches of electrical conductive material adhering to
`2006.O1
`HOB II/02
`each side. Patches on one side can be longitudinally offset
`(
`.01)
`from patches on the opposite side. The patches can be elec
`(52) U.S. Cl. ........ grgrrr. 174/113 R; 174/36
`trically isolated from one another. The tape can be wrapped
`(58) Field of Classification Search .................... 174/36,
`1747 108, 109, 113 R around one or more conductors, such as wires that transmit
`See application file for complete search history.
`data, to provide electrical or electromagnetic shielding. The
`patches can circumferentially encase the conductors, with
`References Cited
`patches on one side of the tape covering gaps on the other side
`of the tape. The tape can be wrapped around the conductors so
`that an edge of a patch spirals about the conductors in a
`rotational direction opposite to any twisting of the conduc
`tors. The resulting cable can have a shield that is electrically
`discontinuous between opposite ends of the cable.
`26 Claims, 8 Drawing Sheets
`
`(56)
`
`
`
`U.S. PATENT DOCUMENTS
`3,373.475 A
`3, 1968 Petersen
`4,604,497 A
`8, 1986 Bell et al.
`4,638,272 A
`1, 1987 Ive
`5,006,806 A
`4, 1991 Rippingale
`5,106,175 A
`4, 1992 Davis et al.
`5,114,517 A
`5/1992 Rippingale et al.
`
`Page 1 of 18
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`U.S. Patent
`U.S. Patent
`
`Apr. 12, 2011
`Apr. 12, 2011
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`Sheet 1 of 8
`Sheet 1 of 8
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`US 7.923,641 B2
`US 7,923,641 B2
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` eeBoeke
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`Fig. 1
`Fig. 7
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`Page 2 of 18
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`U.S. Patent
`U.S. Patent
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`Apr. 12, 2011
`Apr. 12, 2011
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`Sheet 2 of 8
`Sheet 2 of 8
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`US 7.923,641 B2
`US 7,923,641 B2
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`Fig. 2B
`Fig. 28
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`Page 3 of 18
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`U.S. Patent
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`Apr. 12, 2011
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`Sheet 3 of 8
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`US 7.923,641 B2
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`Start Manufacture Cable with Segmented Tape Process
`
`Flat-sheet extruder produces roll of film of dielectric material, such as plastic,
`polymeric material, or polyester
`
`Material handling system transports roll of dielectric film to a metallization
`machine
`
`p1 300
`
`305
`
`310
`
`315
`Metallization machine unwinds roll of dielectric film; applies intermittent strips or
`patches of a conductive material, such as aluminum or copper, as the dielectric
`film is unwound; and winds the resulting film onto a take-up reel
`
`320
`Material handling system transports roll of film with conductive patches to slitting
`machine
`
`Operator enters diameter of cable(s) (or of cable cores) into slitting controller
`)
`
`Controller moves slitting knives of the slitting machine to widths corresponding
`to circumferences of the Cables
`
`325
`
`330
`
`Slitting machine unwinds the roll of film with conductive patches, slits the film
`into slender, intermittently conductive segments or segmented tapes, and winds
`each resulting tape onto a separate roll or spool
`
`
`
`335
`
`Fig. 3A
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`Page 4 of 18
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`U.S. Patent
`
`Apr. 12, 2011
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`Sheet 4 of 8
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`US 7.923,641 B2
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`Material handling system transports roll of segmented tape of appropriate width
`to cabling system and loads roll onto feed spindle
`
`340
`
`345
`
`Material handling system loads one, or two, or more reels of twisted pairs of
`conductors into feed area of cabling system
`
`350
`Cabling system unwinds roll of segmented tape and one or more reels of twisted
`pairs of conductors. The cabling system's feeding mechanisms position the
`twisted pairs of Conductors adjacent the tape as each is unwound, e.g. so that
`the conductors are on top of the flat surface of the tape.
`
`A curling mechanism of the cabling system curls the segmented tape over the
`conductor pairs as they move synchronously or continuously downstream in the
`production line. Thus, the segmented tape is wrapped lengthwise around the
`Conductors.
`
`355
`
`
`
`360
`
`Extruder of cabling system extrudes jacket over the segmented tape and the
`conductor pairs, Thus, the cabling system produces a cable with the Conductors
`and the shielding film in the core of the cable, wherein the segmented tape
`provides a segmented shield for the conductors.
`
`Take-up reel at downstream end of cabling system accumulates finished cable
`
`365
`
`End
`
`Fig. 3B
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`Apr. 12, 2011
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`Sheet 5 of 8
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`Fig. 4B
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`Fig. iC
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`U.S. Patent
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`Apr. 12, 2011
`Apr. 12, 2011
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`Sheet 6 of 8
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`US 7.923,641 B2
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`Sheet 7 of 8
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`US 7.923,641 B2
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`gººgºººººººeeeeeeeeeeeeeee;
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`Fig. 5B
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`Fig. 5C
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`rig. 3D
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`U.S. Patent
`U.S. Patent
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`Apr. 12, 2011
`Apr. 12, 2011
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`Sheet 8 of 8
`Sheet 8 of 8
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`US 7.923,641 B2
`US 7,923,641 B2
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`FOO
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`Fig. 7B
`Fig. 7B
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`US 7,923,641 B2
`
`1.
`COMMUNICATION CABLE COMPRISING
`ELECTRICALLY SOLATED PATCHES OF
`SHIELDING MATERAL
`
`2
`Accordingly, to address these representative deficiencies in
`the art, what is needed is an improved capability for shielding
`conductors that may carry high-speed communication sig
`nals. Another need exists for a method and apparatus for
`efficiently manufacturing communication cables that are
`resistant to noise. Yet another need exists for a cable construc
`tion that effectively suppresses crosstalk and/or other inter
`ference without providing an electrically conductive path
`between ends of the cable. A capability addressing one or
`more of Such needs would support increasing bandwidth
`without unduly increasing cost or installation complexity.
`
`SUMMARY
`
`The present invention Supports providing shielding for
`cables that may communicate data or other information.
`In one aspect of the present invention, a tape can comprise
`a narrow strip of dielectric material, for example in the form
`of a film, with two sides. Electrically conductive areas or
`patches can be disposed against each side of the tape, with the
`conductive patches electrically isolated from one another.
`The patches can comprise aluminum, copper, a metallic Sub
`stance, or some other material that readily conducts electric
`ity. The patches can be printed, fused, transferred, bonded,
`vapor deposited, imprinted, coated, or otherwise attached to
`or disposed adjacent to the strip of dielectric material. On
`each side of the tape, electrically isolating gaps can be dis
`posed between adjacent patches. The patches on one side of
`the tape can cover the gaps on the other side of the tape. The
`tape can be wrapped around signal conductors, such as wires
`that transmit data, to provide electrical or electromagnetic
`shielding for the conductors. The combination of sections or
`segments of conductive shielding can Substantially circum
`scribe or circumferentially encase the signal conductors. That
`is, any significant circumferential area not covered by patches
`on one side of the tape can be covered by patches on the
`opposite side of the tape.
`The tape and/or the resulting shield can be electrically
`discontinuous between opposite ends of a cable. While elec
`tricity can flow freely in each individual section of shielding,
`the isolating gaps can provide shield discontinuities for inhib
`iting electricity from flowing in the shielding material along
`the full length of the cable.
`The discussion of shielding conductors presented in this
`Summary is for illustrative purposes only. Various aspects of
`the present invention may be more clearly understood and
`appreciated from a review of the following detailed descrip
`tion of the disclosed embodiments and by reference to the
`drawings and the claims that follow. Moreover, other aspects,
`systems, methods, features, advantages, and objects of the
`present invention will become apparent to one with skill in the
`art upon examination of the following drawings and detailed
`description. It is intended that all Such aspects, systems, meth
`ods, features, advantages, and objects are to be included
`within this description, are to be within the scope of the
`present invention, and are to be protected by the accompany
`ing claims.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is a cross sectional view of an exemplary commu
`nication cable that comprises a segmented shield in accor
`dance with certain embodiments of the present invention.
`FIGS. 2A and 2B are, respectively, overhead and cross
`sectional views of an exemplary segmented tape that com
`
`CROSS REFERENCE TO RELATED
`APPLICATIONS
`
`This application is a continuation-in-part of and claims
`priority to U.S. patent application Ser. No. 1 1/502,777, filed
`Aug. 11, 2006 now abandoned in the name of Delton C. Smith
`et al. and entitled “Method and Apparatus for Fabricating
`Noise-Mitigating Cable the entire contents of which are
`hereby incorporated herein by reference.
`This application is related to the co-assigned U.S. patent
`application entitled “Communication Cable Comprising
`Electrically Discontinuous Shield Having Nonmetallic
`Appearance filed concurrently herewith under and assigned
`U.S. patent application No. 12/313,910, the entire contents of
`which are hereby incorporate herein by reference.
`
`10
`
`15
`
`FIELD OF THE TECHNOLOGY
`
`The present invention relates to communication cables that
`are shielded from electromagnetic radiation and more spe
`25
`cifically to a communication cable shielded with patches of
`conductive material adhering to a dielectric film that is
`wrapped around wires of the cable.
`
`BACKGROUND
`
`As the desire for enhanced communication bandwidth
`escalates, transmission media need to convey information at
`higher speeds while maintaining signal fidelity and avoiding
`crosstalk. However, effects such as noise, interference,
`crosstalk, alien crosstalk, and alien elfext crosstalk can
`strengthen with increased data rates, thereby degrading signal
`quality or integrity. For example, when two cables are dis
`posed adjacent one another, data transmission in one cable
`can induce signal problems in the other cable via crosstalk
`interference.
`One approach to addressing crosstalk between communi
`cation cables is to circumferentially encase each cable in a
`continuous shield, such as a flexible metallic tube or a foil that
`coaxially surrounds the cable's conductors. However, shield
`ing based on convention technology can be expensive to
`manufacture and/or cumbersome to install in the field. In
`particular, complications can arise when a cable is encased by
`a shield that is electrically continuous between the two ends
`of the cable.
`In a typical application, each cable end is connected to a
`terminal device Such as an electrical transmitter, receiver, or
`transceiver. The continuous shield can inadvertently carry
`Voltage along the cable, for example from one terminal device
`at one end of the cable towards another terminal device at the
`other end of the cable. If a person contacts the shielding, the
`person may receive a shock if the shielding is not properly
`grounded. Accordingly, continuous cable shields are typi
`cally grounded at both ends of the cable to reduce shock
`hazards and loop currents that can interfere with transmitted
`signals.
`Such a continuous shield can also set up standing waves of
`electromagnetic energy based on signals received from
`nearby energy sources. In this scenario, the shield's standing
`wave can radiate electromagnetic energy, somewhat like an
`antenna, that may interfere with wireless communication
`devices or other sensitive equipment operating nearby.
`
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`US 7,923,641 B2
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`5
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`10
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`15
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`3
`prises a pattern of conductive patches attached to a dielectric
`film substrate in accordance with certain embodiments of the
`present invention.
`FIG. 2C is an illustration of an exemplary technique for
`wrapping a segmented tape lengthwise around a pair of con
`ductors in accordance with certain embodiments of the
`present invention.
`FIGS. 3A and 3B, collectively FIG. 3, are a flowchart
`depicting an exemplary process for manufacturing cable in
`accordance with certain embodiments of the present inven
`tion.
`FIGS. 4A, 4B, and 4C, collectively FIG.4, are illustrations
`of exemplary segmented tapes comprising conductive
`patches disposed on opposite sides of a dielectric film in
`accordance with certain embodiments of the present inven
`tion.
`FIGS.5A, 5B, 5C, and 5D, collectively FIG. 5, are illus
`trations, from different viewing perspectives, of an exemplary
`segmented tape comprising conductive patches disposed on
`opposite sides of a dielectric film in accordance with certain
`embodiments of the present invention.
`FIG. 6 is an illustration of an exemplary geometry for a
`conductive patch of a segmented tape in accordance with
`certain embodiments of the present invention.
`FIG. 7A is an illustration of an exemplary orientation for
`conductive patches of a segmented tape with respect to a
`twisted pair of conductors in accordance with certain embodi
`ments of the present invention.
`FIG. 7B is an illustration of a core of a communication
`30
`cable comprising conductive patches disposed in an exem
`plary geometry with respect to a twist direction of twisted
`pairs and to a twist direction of the cable core in accordance
`with certain embodiments of the present invention.
`Many aspects of the invention can be better understood
`with reference to the above drawings. The elements and fea
`tures shown in the drawings are not to Scale, emphasis instead
`being placed upon clearly illustrating the principles of exem
`plary embodiments of the present invention. Moreover, cer
`tain dimension may be exaggerated to help visually convey
`Such principles. In the drawings, reference numerals desig
`nate like or corresponding, but not necessarily identical, ele
`ments throughout the several views.
`
`4
`The invention can be embodied in many different forms
`and should not be construed as limited to the embodiments set
`forth herein; rather, these embodiments are provided so that
`this disclosure will be thorough and complete, and will fully
`convey the scope of the invention to those having ordinary
`skill in the art. Furthermore, all “examples’ or “exemplary
`embodiments’ given herein are intended to be non-limiting,
`and among others Supported by representations of the present
`invention.
`Turning now to FIG. 1, this figure illustrates a cross sec
`tional view of a communication cable 100 that comprises a
`segmented shield 125 according to certain exemplary
`embodiments of the present invention.
`The core 110 of the cable 100 contains four pairs of con
`ductors 105, four being an exemplary rather than limiting
`number. Each pair 105 can be a twisted pair that carries data,
`for example in a range of 1-10Gbps or some other appropriate
`range. The pairs 105 can each have the same twist rate (twists
`per-meter or twists-per-foot) or may be twisted at different
`rates.
`The core 110 can be hollow as illustrated or alternatively
`can comprise a gelatinous, Solid, or foam material, for
`example in the interstitial spaces between the individual con
`ductors 105. In one exemplary embodiment, one or more
`members can separate each of the conductor pairs 105 from
`the other conductor pairs 105. For example, the core 110 can
`contain an extruded or pultruded separator that extends along
`the cable 110 and that provides a dedicated cavity or channel
`for each of the four conductor pairs 105. Viewed end-on or in
`cross section, the separator could have a cross-shaped geom
`etry or an X-shaped geometry.
`Such an internal separator can increase physical separation
`between each conductor pair 105 and can help maintain a
`random orientation of each pair 105 relative to the other pairs
`105 when the cable 100 is field deployed.
`A segmented tape 125 surrounds and shields the four con
`ductor pairs 105. As discussed in further detail below, the
`segmented tape 125 comprises a dielectric substrate 150 with
`patches 175 of conductive material attached thereto. As illus
`trated, the segmented tape 125 extends longitudinally along
`the length of the cable 100, essentially running parallel with
`and wrapping over the conductors 105.
`In an alternative embodiment, the segmented tape 125 can
`wind helically or spirally around the conductor pairs 105.
`More generally, the segmented tape 125 can circumferen
`tially cover, house, encase, or enclose the conductor pairs
`105. Thus, the segmented tape 125 can circumscribe the
`conductors 105, to extend around or over the conductors 105.
`Although FIG. 1 depicts the segmented tape 125 as partially
`circumscribing the conductors 105, that illustrated geometry
`is merely one example. In many situations, improved block
`age of radiation will result from overlapping the segmented
`tape 125 around the conductors 105, so that the segmented
`tape fully circumscribes the conductors 105. Moreover, in
`certain embodiments, the side edges of the segmented tape
`125 can essentially butt up to one another around the core 110
`of the cable 100. Further, in certain embodiments, a signifi
`cant gap can separate these edges, so that the segmented tape
`125 does not fully circumscribe the core 110.
`In one exemplary embodiment, one side edge of the seg
`mented tape 125 is disposed over the other side edge of the
`tape 125. In other words, the edges can overlap one another,
`with one edge being slightly closer to the center of the core
`110 than the other edge.
`An outerjacket 115 of polymer seals the cable 110 from the
`environment and provides strength and structural Support.
`The jacket 115 can be characterized as an outer sheath, a
`
`25
`
`35
`
`40
`
`DETAILED DESCRIPTION OF EXEMPLARY
`EMBODIMENTS
`
`45
`
`The present invention Supports shielding a communication
`cable, wherein at least one break or discontinuity in a shield
`ing material electrically isolates shielding at one end of the
`cable from shielding at the other end of the cable. As an
`alternative to forming a continuous or contiguous conductive
`path, the tape can be segmented or can comprise intermit
`tently conductive patches or areas.
`Cables comprising segmented tapes, and technology for
`making such cables, will now be described more fully here
`inafter with reference to FIGS. 1-7, which describe represen
`tative embodiments of the present invention. In an exemplary
`embodiment, the segmented tape can be characterized as
`shielding tape or as tape with segments or patches of conduc
`tive material. FIG. 1 provides an end-on view of a cable
`comprising segmented tape. FIGS. 2A, 2B, 4, 5, and 6 illus
`trate representative segmented tapes. FIG. 2C depicts wrap
`ping segmented tape around or over conductors. FIG.3 offers
`a process for making cable with segmented shielding. FIGS.
`7A and 7B (collectively Figure &) describe orientations of
`patches in cables.
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`US 7,923,641 B2
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`5
`jacket, a casing, or a shell. A Small annular spacing 120 may
`separate the jacket 115 from the segmented tape 125.
`In one exemplary embodiment, the cable 100 or some other
`similarly noise mitigated cable can meet a transmission
`requirement for “10G Base-T data corn cables. In one exem
`plary embodiment, the cable 100 or some other similarly
`noise mitigated cable can meet the requirements set forth for
`10Gbps transmission in the industry specification known as
`TIA 568-B.2-10 and/or the industry specification known as
`ISO 11801. Accordingly, the noise mitigation that the seg
`mented tape 125 provides can help one or more twisted pairs
`of conductors 105 transmit data at 10Gbps or faster without
`unduly experiencing bit errors or other transmission impair
`ments. As discussed in further detail below, an automated and
`scalable process can fabricate the cable 100 using the seg
`mented tape 125.
`Turning now to FIGS. 2A and 2B, these figures respec
`tively illustrate overhead and cross sectional views of a seg
`mented tape 125 that comprises a pattern of conductive
`patches 175 attached to a dielectric substrate 150 according to
`certain exemplary embodiments of the present invention.
`That is, FIGS. 2A and 2B depict an exemplary embodiment of
`the segmented tape 125 shown in FIG. 1 and discussed above.
`More specifically, FIG. 1 illustrates a cross sectional view of
`25
`the cable 100 wherein the cross section cuts through one of
`the conductive patches 175, perpendicular to the major axis of
`the segmented tape 125.
`The segmented tape 125 comprises a dielectric substrate
`film 150 of flexible dielectric material that can be wound
`around and stored on a spool. That is, the illustrated section of
`segmented tape 125 can be part of a spool of segmented tape
`125. The film can comprise a polyester, polypropylene, poly
`ethylene, polyimide, or some other polymer or dielectric
`material that does not ordinarily conduct electricity. That is,
`the segmented tape 125 can comprise a thin strip of pliable
`material that has at least some capability for electrical insu
`lation. In one exemplary embodiment, the pliable material
`can comprise a membrane or a deformable sheet. In one
`exemplary embodiment, the substrate is formed of the poly
`ester material sold by E.I. DuPont de Nemours and Company
`under the registered trademark MYLAR.
`The conductive patches 175 can comprise aluminum, cop
`per, nickel, iron, or some metallic alloy or combination of
`materials that readily transmits electricity. The individual
`45
`patches 175 can be separated from one another so that each
`patch 175 is electrically isolated from the other patches 175.
`That is, the respective physical separations between the
`patches 175 can impede the flow of electricity between adja
`cent patches 175.
`The conductive patches 175 can span fully across the seg
`mented tape 125, between the tape's long edges. As discussed
`in further detail below, the conductive patches 175 can be
`attached to the dielectric substrate 150 via gluing, bonding,
`adhesion, printing, painting, welding, coating, heated fusion,
`melting, or vapor deposition, to name a few examples.
`In one exemplary embodiment, the conductive patches 175
`can be over-coated with an electrically insulating film, Such as
`a polyester coating (not shown in FIGS. 2A and 2B). In one
`exemplary embodiment, the conductive patches 175 are sand
`wiched between two dielectric films, the dielectric substrate
`150 and another electrically insulating film (not shown in
`FIGS. 2A and 2B).
`The segmented tape 125 can have a width that corresponds
`to the circumference of the core 110 of the cable 100. The
`width can be slightly Smaller than, essentially equal to, or
`larger than the core circumference, depending on whether the
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`6
`longitudinal edges of the segmented tape 125 are to be sepa
`rated, butted together, or overlapping, with respect to one
`another in the cable 100.
`In one exemplary embodiment, the dielectric substrate 150
`has a thickness of about 1-5 mils (thousandths of an inch) or
`about 25-125 microns. Each conductive patch 175 can com
`prise a coating of aluminum having a thickness of about 0.5
`mils or about 13 microns. In many applications, signal per
`formance benefits from a thickness that is greater than 2 mils,
`for example in a range of 2.0 - 2.5 mils, or 2.0-3.0 mils.
`Each patch 175 can have a length of about 1.5 to 2 inches or
`about 4 to 5 centimeters. Other exemplary embodiments can
`have dimensions following any of these ranges, or some other
`values as may be useful. The dimensions can be selected to
`provide electromagnetic shielding over a specific band of
`electromagnetic frequencies or above or below a designated
`frequency threshold, for example.
`In certain exemplary embodiments, each patch 175 has a
`length of about 2 meters, with the gaps between adjacent
`patches 175 about /16 of an inch. The resulting shield con
`figuration provides a return loss Spike in the operating band of
`the cable 100, which should be avoided by conventional
`thinking. However, the spike is unexpectedly Suppressed,
`thereby providing an acceptable cable with segment and gap
`dimensions that offer manufacturing advantages. Thus,
`increasing the patch lengths benefits manufacturing while
`providing acceptable performance. The peak in return loss is
`surprisingly suppressed, and the cable 100 meets perfor
`mance standards and network specifications.
`In certain exemplary embodiments, each patch 175 covers
`a hole (not illustrated) in the dielectric substrate 150. In other
`words, the dielectric substrate 150 comprises holes or win
`dows, with a patch 175 disposed over each hole or window.
`Typically, each patch 175 is slightly bigger than its associated
`window, so the patch 175 extends over the window edges. The
`windows eliminate a substantial portion of the flammable
`film substrate material, thereby achieving betterburn charac
`teristics, via producing less Smoke, heat, and flame.
`Turning now to FIG. 2C, this figure illustrates wrapping a
`segmented tape 125 lengthwise around a pair of conductors
`105 according to certain exemplary embodiments of the
`present invention. Thus, FIG. 2C shows how the segmented
`tape 125 discussed above can be wrapped around or over one
`or more pairs of conductors 125 as an intermediate step in
`forming a cable 100 as depicted in FIG. 1 and discussed
`above. While FIG.1 depicts four pairs of wrapped conductors
`105, FIG. 2C illustrates wrapping a single pair 105 as an aid
`to visualizing an exemplary assembly technique.
`As illustrated in FIG. 2C, the pair of conductors 105 is
`disposed adjacent the segmented tape 125. The conductors
`105 extend essentially parallel with the major or longitudinal
`axis/dimension of the segmented tape 125. Thus, the conduc
`tors 105 can be viewed as being parallel to the surface or plane
`of the segmented tape 125. Alternatively, the conductors 105
`can be viewed as being over or under the segmented tape 125
`or being situated along the center axis of the segmented tape
`125. Moreover, the conductors 105 can be viewed as being
`essentially parallel to one or both edges of the segmented tape
`125.
`In most applications the conductors 105, which are typi
`cally individually insulated, will betwisted together to form a
`twisted pair. And, the segmented tape 125 will wrap around
`the twisted pair as discussed below. FIG. 7A, discussed
`below, illustrates such an embodiment. In certain embodi
`ments, multiple twisted pairs of conductors 105 will be
`twisted, bunched, or cabled together, with the segmented tape
`125 providing a circumferential covering.
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`7
`The long edges of the segmented tape 125 are brought up
`over the conductors 105, thereby encasing the conductors 105
`or wrapping the segmented tape 125 around or over the con
`ductors 105. In an exemplary embodiment, the motion can be
`characterized as folding or curling the segmented tape 125
`over the conductors 105. As discussed above, the long edges
`of the segmented tape 125 can overlap one another following
`the illustrated motion.
`In certain exemplary embodiments, the segmented tape
`125 is wrapped around the conductors 105 without substan
`tially spiraling the segmented tape 125 around or about the
`conductors. Alternatively, the segmented tape 125 can be
`wrapped so as to spiral around the conductors 105.
`In one exemplary embodiment, the conductive patches 175
`face inward, towards the conductors 105. In another exem
`plary embodiment, the conductive patches 175 face away
`from the conductors 105, towards the exterior of the cable
`1OO.
`In one exemplary embodiment, the segmented tape 125
`and the conductors 105 are continuously fed from reels, bins,
`containers, or other bulk storage facilities into a narrowing
`chute or a funnel that curls the segmented tape 125 over the
`conductors 105.
`In one exemplary embodiment, FIG. 2C describes opera
`tions in a Zone of a cabling machine, wherein segmented tape
`125 fed from one reel (not illustrated) is brought into contact
`with conductors 105 feeding off of another reel. That is, the
`segmented tape 125 and the pair of conductors 105 can syn
`chronously and/or continuously feed into a chute or a mecha
`nism that brings the segmented tape 125 and the conductors
`105 together and that curls the segmented tape 125 lengthwise
`around the conductors 105. So disposed, the segmented tape
`125 encircles or encases the conductors 105 in discontinuous,
`conductive patches.
`Downstream from this mechanism (or as a component of
`this mechanism), a nozzle or outlet port can extrude a poly
`meric jacket, skin, casing, or sheath 115 over the segmented
`tape, thus providing the basic architecture depicted in FIG. 1
`and discussed above.
`Turning now to FIG. 3, this figure is a flowchart depicting
`a process 300 for manufacturing cable 100 according to cer
`tain exemplary embodiments of the present invention. Pro
`cess 300 can produce the cable 100 illustrated in FIG. 1 using
`the segmented tape 125 and the conductors 105 as base mate
`rials.
`At Step 305 an extruder produces a film of dielectric mate
`rial. Such as polyester, which is wound onto a roll or a reel. At
`this stage, the film can be much wider than the circumference
`of any particular cable in which it may ultimately be used and
`might be one to three meters across, for example. As dis
`cussed in further detail below, the extruded film will be pro
`cessed to provide the dielectric substrate 150 discussed
`above.
`At Step 310, a material handling system transports the roll
`to a metallization machine or to a metallization station. The
`material handling system can be manual, for example based
`on one or more human operated forklifts or may alternatively
`be automated, thereby requiring minimal, little, or essentially
`no human intervention during routine operation. The material
`handling may also be tandemized with a film producing sta
`tion. Material handing can also comprise transporting mate
`rials between production facilities or between vendors or
`independent companies, for example via a Supplier relation
`ship.
`At Step 315, the metallization machine unwinds the roll of
`dielectric film and applies a pattern of conductive patches 175
`to the film. The patches 175 typically comprise strips that
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`US 7,923,641 B2
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`extend across the roll, perpendicular to the flow of the film off
`of the roll. The patches 175 are typically formed while the
`sheet offilm is moving from a payoff roll (or reel) to a take-up
`roll (or reel). As discussed in further detail below, the result
`ing material will be further processed to provide multiple of
`the segmented tapes 125 discussed above.
`In certain exemplary embodiments, the metallization
`machine can apply the conductive patches 175 to the dielec
`tric substrate 150 by coating the moving sheet of diele