(12) United States Patent
`Barton
`
`USOO6378283B1
`(10) Patent No.:
`US 6,378,283 B1
`(45) Date of Patent:
`Apr. 30, 2002
`
`(54)
`
`(75)
`(73)
`
`(21)
`(22)
`(51)
`(52)
`
`(58)
`
`(56)
`
`MULTIPLE CONDUCTOR ELECTRICAL
`CABLE WITH MINIMIZED CROSSTALK
`
`Inventor: John A. Barton, Bellingham, MA (US)
`Assignee: Helix/HiTemp Cables, Inc., Franklin,
`MA (US)
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`
`Notice:
`
`Appl. No.: 09/578,289
`Filed:
`May 25, 2000
`Int. Cl................................................... D01H 1/10
`U.S. C. ......
`... 57/58.52; 57/58.49; 57/58.63;
`57/58.65; 57/58.7; 57/58.72; 57/58.81;
`59/60; 59/61; 59/62; 59/63; 59/64; 66/314
`Field of Search ............................. 57/58.49, 58.52,
`57/58.63, 58.65, 58.7, 58.72, 58.81, 59,
`60, 61, 62, 63, 64, 66,314
`
`References Cited
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`
`FOREIGN PATENT DOCUMENTS
`
`DE
`EP
`EP
`EP
`
`........... HO1B/11/08
`3/1995
`4336230 C1
`... HO4B/3/OO
`2/1987
`O211750 B1
`... HO4B/3/OO
`O211750 A2 2/1987
`O763831
`3/1997 ........... HO1B/11/06
`(List continued on next page.)
`OTHER PUBLICATIONS
`“Engineering Design Guide' C&M Corporation, pp. 10-11,
`1992.
`images of Belden 1711A Datatwist 300 4PR23 shielded
`cable, Sep. 11, 1995.
`Norblad, Sigurd, “Cross-stranding of telephone cables”,
`Telecommunication Journal, vol. 41, No. 4, 1974, pp.
`261-266.
`Primary Examiner John J. Calvert
`Assistant Examiner Shaun R Hurley
`(74) Attorney, Agent, or Firm Testa, Hurwitz & Thibeault,
`LLP
`ABSTRACT
`(57)
`A process and apparatus for manufacturing multiple con
`ductor cable having improved transmission parameters. The
`apparatus includes a rotatable alignment die having a plu
`rality of apertures. At least one Strand of the multiple
`conductor cable is caused to traverse an aperture of the
`rotatable alignment die. A rotation motor causes the Strand
`to rotate about its elongate axis, and a translation motor
`causes the Strand, or the cable, to traverse along its elongate
`axis. The multiple conductors are brought into a predeter
`mined mutual mechanical alignment that is calculated to
`produce a cable having at least one improved transmission
`parameter. The cable can additionally include a Support
`member adapted to maintain the conductors in the mutual
`mechanical alignment. A binder is applied to the cable to
`maintain the conductors in the predetermined mutual align
`ment. Tests performed on cable manufactured using the
`principles of the invention demonstrate improved transmis
`Sion characteristics as compared to cable made without
`using the principles of the invention.
`
`11 Claims, 9 Drawing Sheets
`
`
`
`

`

`US 6,378,283 B1
`Page 2
`
`U.S. PATENT DOCUMENTS
`
`7/1998 Meggle ....................... 59/264
`5,782,075 A
`5,789,711 A 8/1998 Gaeris et al. ........... 174/113 C
`5,841,072 A 11/1998 Gagnon .................. 174/110 F
`4,429.520 A 2/1984 Garner et al. ................. 57/293
`5.841,073. A 11/1998 Randa et al. ..
`174/113 R
`4,450,674. A 5/1984 Bos et al..
`... 57/6
`5,887,032 A 3/1999 Cioff ............
`... 375/257
`4,530.205 A 7/1985 Seiler et al.
`... 57/9
`5,921,818 A 7/1999 Larsen et al. ..
`... 439/676
`4,600,268 A 7/1986 Spicer .......
`... 350/96.23
`5,926,509 A 7/1999 Stewart et al. .............. 375/257
`4,677,816 A * 7/1987 Woxholt ........................ 57/59
`5,931,474 A 8/1999 Chang et al. .....
`... 277/316
`4,697,051 A 9/1987 Beggs et al.
`... 178/63 D
`5,952.607 A 9/1999 Friesen et al. ................ 174/34
`4,778.246 A 10/1988 Carroll ......
`... 350/96.23
`5,952,615 A 9/1999 Prudhon ...........
`... 174/113 C
`4,807,962 A 2/1989 Arroyo et al.
`350/96.23
`5,969.295 A 10/1999 Boucino et al. ........ 174/113 C
`4,865,086 A 9/1989 Robinson et al
`... 140/118
`6,017,237 A
`1/2000 Sullivan ...........
`... 439/392
`4,873,393 A 10/1989 Friesen et al.
`... 174/34
`6,074,503 A 6/2000 Clark et al. ................... 156/50
`5.010210 A 4/1991 Sidi et al. .....
`174/34
`6,150,612 A 11/2000 Grandy et al. .......... 174/113 C
`5,149,915 A 9/1992 Brunker et al. ..
`174/36
`6,153,826. A 11/2000 Kenny et al. ................. 174/27
`5,162,609. A 11/1992 Adriaenssens et al. ........ 174/34
`5,177.809 A
`1/1993 Zeidler ...............
`... 385/105
`FOREIGN PATENT DOCUMENTS
`5,289,556 A 2/1994 Rawlyket al.
`... 385/112
`0883139 A1 12/1998 ........... HO1B/11/04
`5,418,878 A
`5/1995 Sasset al.
`.
`3.85/101
`EP
`5,424,491 A 6/1995 Walling et al.
`174/113 R
`09139121
`5/1997
`HO1B/11/04
`JP
`5,438,571. A 8/1995 Albrecht et al.
`... 370/94.3
`WO96/41908
`12/1996
`... D01H/1/10
`WO
`5,544.270 A 8/1996 Clark et al.
`... 385/101
`WO98/48430
`10/1998
`HO1B/11/08
`WO
`5,563,377. A 10/1996 Arpin et al.
`174/121 A WO
`WO99/54889
`10/1999
`........... HO1B/11/02
`WOO1/08167 A1
`2/2001
`HO1B/7/18
`5,574.250 A 11/1996 Hardie et al. .
`... 174/36
`WO
`" -v or ,
`, ,
`-, -v ...........
`7/1997 Josoff ............................ 57.67
`'' -
`5,647,195 A
`5,689,090 A 11/1997 Bleich et al. .......... 174/121 A * cited by examiner
`
`
`
`

`

`U.S. Patent
`
`Apr. 30, 2002
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`Sheet 1 of 9
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`US 6,378,283 B1
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`Apr. 30, 2002
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`US 6,378,283 B1
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`U.S. Patent
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`Apr. 30, 2002
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`Sheet 2 of 9
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`US 6,378,283 B1
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`U.S. Patent
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`Apr. 30, 2002
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`U.S. Patent
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`Apr. 30, 2002
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`Apr. 30, 2002
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`U.S. Patent
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`Apr. 30, 2002
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`Sheet 4 of 9
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`US 6,378,283 B1
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`U.S. Patent
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`Apr. 30, 2002
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`Sheet 4 of 9
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`US 6,378,283 B1
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`U.S. Patent
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`Apr. 30, 2002
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`Sheet 5 of 9
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`Apr. 30, 2002
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`U.S. Patent
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`Apr. 30, 2002
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`Sheet 6 of 9
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`Sheet 6 of 9
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`Apr. 30, 2002
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`U.S. Patent
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`Apr. 30, 2002
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`Sheet 7 of 9
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`U.S. Patent
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`Apr. 30, 2002
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`Sheet 7 of 9
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`Apr. 30, 2002
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`U.S. Patent
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`Apr. 30, 2002
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`U.S. Patent
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`Apr. 30, 2002
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`US 6,378,283 B1
`
`1
`MULTIPLE CONDUCTOR ELECTRICAL
`CABLE WITH MINIMIZED CROSSTALK
`
`FIELD OF THE INVENTION
`This invention relates generally to Systems and methods
`for manufacturing multiple conductor electrical cable. More
`particularly, the invention relates to Systems and methods for
`manufacturing multiple conductor electrical cable that
`exhibits an improved croSStalk margin relative to industry
`Standards, as well as cable produced by Such Systems and
`methods.
`
`BACKGROUND OF THE INVENTION
`Multiple conductor electrical cable for use in applications
`Such as telecommunication and communication between
`computers are well known. Nevertheless, the increases in
`transmission rates, measured in bits of information per
`Second, required to transmit large amounts of information at
`high Speed Severely tax the capabilities of conventional
`multiple conductor electrical cables. For example, computer
`communications using data rates of more than one gigabit
`per Second are now contemplated using inexpensive twisted
`pair electrical cable, rather than more expensive transmis
`Sion media Such as coaxial cable. Transmission rates of the
`order of a gigabit per Second have been considered excessive
`for Systems that rely on twisted pair copper conductor cable,
`based on high levels of electromagnetic interference that
`were expected to be encountered. Recent advances in elec
`tronics have created a need for cable that can accommodate
`high transmission rates, Such as a gigabit per Second, with
`acceptably low noise, low crosstalk, and low cost.
`While multiple conductor electrical cable, including
`twisted pair cable, has been in use for many years, there are
`Significant problems in making twisted pair cable that can
`perform within the requirements of technical Standards Such
`as TIA/EIA-568-A Commercial Building Telecommunica
`tions Cabling Standard, known as Category 5e, the disclo
`Sure of which is incorporated herein by reference in its
`entirety. Extended lengths (for example, greater than 100
`meters, or approximately 328 feet) of twisted pair cable
`made by the methods of the prior art often fail to satisfy the
`Category 5e Standard. However, for a cable manufacturing
`method to be useful, one must routinely Satisfy the Standard
`of performance for cable that exceeds a length of 100 meters
`or even a length of 1000 meters.
`
`SUMMARY OF THE INVENTION
`The present invention provides Systems and methods for
`manufacturing multiple conductor electrical cable with
`improved transmission parameters, for example, reduced
`crosstalk, than is possible using the Systems and methods of
`the prior art. The multiple conductor electrical cable pro
`duced using the Systems and methods of the invention
`exhibits both improvements in the transmission parameters
`and reductions in the variations in the transmission param
`eters that control the quality of the transmission as compared
`to cable manufactured without the Systems and methods of
`the invention. For example, cable made according to the
`teachings of the invention exhibit increased margins by
`which the transmission parameters exceed the requirements
`Specified in Category 5e, as compared to cable made without
`the Systems and methods of the invention.
`Some of the advantages that the Systems and methods of
`the invention provide include higher quality multiple con
`ductor electrical cable, greater assurance that manufactured
`
`15
`
`25
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`2
`cable will meet or exceed the Specifications required to
`conform to an industrial Standard (e.g., that the cable will be
`acceptable for use, or “merchantable”), higher rates of
`production, and lower incremental costs to implement the
`Systems and methods of the invention.
`In one aspect, the invention features a multiple conductor
`cable that includes a plurality of elongate conductors dis
`posed in a predefined mutual mechanical alignment. This
`mutual mechanical alignment is calculated to provide a
`cable that includes at least one transmission parameter
`optimized with respect to Category 5e. The mutual mechani
`cal alignment of the cable is defined by a rate of advance of
`at least one of the conductors through a rotatable alignment
`die and a rate of rotation of at least one of the conductors
`Substantially about its elongate axis. In Some embodiments,
`a binder may be applied to the plurality of conductors.
`In one embodiment, the invention may include the mul
`tiple conductor cable in which at least one transmission
`parameter Selected from the group of transmission param
`eters consisting of input impedance, characteristic
`impedance, resistance unbalance, mutual capacitance,
`capacitance unbalance to ground, capacitance unbalance to
`shield, attenuation, Near End Cross Talk (“NEXT"), Power
`Sum NEXT, Equal Level Far End Cross Talk (“ELFEXT'),
`and Power Sum ELFEXT is optimized with respect to
`Category 5e.
`In another embodiment, the invention includes the mul
`tiple conductor cable in which the mutual mechanical align
`ment is calculated to provide a cable including a NEXT that
`exceeds the NEXT specified in Category 5e as expressed in
`Table I below by no less than 2 decibels, more preferably no
`less than 5 decibels, and most preferably no less than 10
`decibels.
`
`Table I
`
`Frequency (MHz)
`O.150
`O.772
`1.O
`4.0
`8.0
`1.O.O
`16.0
`2O.O
`25.0
`31.25
`62.5
`1OO.O
`
`NEXT (dB)
`77.7
`67.0
`65.3
`56.3
`51.8
`50.3
`47.3
`45.8
`44.3
`42.9
`38.4
`35.8
`
`In Some embodiments, the invention comprises a multiple
`conductor cable including a binder in which the binder may
`be a tubular sheath, a helical wrapping, a longitudinally
`Slotted sheath, or an array of individual ties. In Some
`embodiments, the invention comprises the multiple conduc
`tor cable in which the binder is made from a material that is
`heat Shrinkable, is flame retardant, and/or is a thermosetter.
`In Some embodiments, the invention includes a multiple
`conductor cable that has a Single twisted pair of conductors,
`or that has multiple twisted pairs of conductors.
`In Some embodiments, the invention includes a multiple
`conductor cable that has a mechanical alignment component
`that is incorporated into the cable to Stabilize the mutual
`mechanical alignment of the conductors. In one
`embodiment, the mechanical alignment component may
`have a finned configuration and the fin(s) may be positioned
`Substantially parallel to the length of the mechanical align
`ment component. The finCS) may be conductive, or,
`alternatively, the fin may be non-conductive.
`
`

`

`3
`In another aspect, the invention features an apparatus for
`manufacturing a multiple conductor cable from a plurality of
`elongate conductors. The apparatus includes a rotatable
`aligning die that includes a plurality of apertures. The
`apparatus includes an applicator that can apply a binder to
`the plurality of conductors. The apparatus may have one or
`more motors that cause the plurality of elongate conductors
`to traverse along its elongate axis, and that also cause the
`plurality of elongate conductors to rotate Substantially about
`its elongate axis. The apparatus causes the plurality of
`elongate conductors to traverse at least one of the apertures
`of the aligning die. The apparatus causes the elongate
`conductors to be brought into a defined mutual mechanical
`alignment. The elongate conductors may be retained in a
`mutual mechanical alignment, at least partially, by the
`application of the binder.
`In Some embodiments, the invention includes an appara
`tus that has a Support situated Substantially along a rotation
`axis of the die. The Support Stabilizes the mutual mechanical
`alignment of the plurality of elongate conductors. In Some
`embodiments, the Support traverses the rotational die and is
`incorporated into the cable that is manufactured.
`In one embodiment, the invention includes a Support
`fixture that can adjustably position the binder applicator
`relative to the position where the elongate conductors are
`brought into mutual mechanical alignment.
`In Some embodiments, the apparatus includes a binder
`applicator adapted to dispense a binder material that can
`bind the plurality of conductors together.
`In one embodiment, the invention includes a rotatable
`aligning die that includes a rotatable body that includes a
`circular periphery and a plurality of apertures through the
`rotatable body. Each of the plurality of apertures is adapted
`to receive one or more elongate conductors. The apertures
`are aligned in the rotatable body Substantially transversely to
`a plane defined by the circular periphery of the rotatable
`body. The rotatable aligning die also includes a fixing collar
`that can be adjustably attached to the apparatus for manu
`facturing a multiple conductor cable. The rotatable body is
`capable of rotating relative to the fixing collar. The rotatable
`aligning die may include at least one ball bearing situated at
`the circular periphery of the rotatable body and Supporting
`the rotatable body within the fixing collar.
`In another aspect, the invention features a rotatable align
`ing die for the manufacture of multiple conductor electrical
`cable, including a rotatable body that includes a circular
`periphery and a plurality of apertures through the rotatable
`body. The apertures are aligned in the body Substantially
`transversely to a plane defined by the circular periphery of
`the body. Each of the plurality of apertures can receive one
`or more elongate electrical conductors. The rotatable align
`ing die includes a fixing collar that can be adjustably
`attached to an apparatus for manufacturing a multiple con
`ductor cable. The rotatable aligning die includes at least one
`ball bearing situated at the circular periphery of the rotatable
`body. The ball bearing(s) support the rotatable body within
`the fixing collar. The rotatable body can rotate relative to the
`fixing collar. The application of rotational force to at least
`one of the electrical conductors causes the rotation of the
`rotatable body.
`In another aspect, the invention features a process for
`manufacturing a multiple conductor cable from a plurality of
`elongate conductors. The process includes the Step of pro
`Viding a rotatable aligning die that includes a plurality of
`apertures, and providing an applicator that can apply a
`binder to at least two of the plurality of conductors. The
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`process includes the Steps of advancing at least one of the
`plurality of elongate conductors through at least one of the
`apertures of the aligning die, and rotating at least one of the
`plurality of elongate conductors about its elongated axis.
`The proceSS includes the Step of bringing the plurality of
`elongate conductors into a defined mutual mechanical align
`ment. The process includes the Step of retaining at least two
`of the plurality of elongate conductors in the mutual
`mechanical alignment at least partially by the application of
`the binder.
`In one embodiment, the invention includes the Step of
`providing a consumable mechanical alignment component
`that is incorporated into the cable to Stabilize the mutual
`mechanical alignment of at least two of the plurality of
`conductors. In another embodiment, the invention includes
`providing a Support member disposed Substantially along a
`rotation axis of the aligning die to Stabilize the mutual
`mechanical alignment of at least two of the plurality of
`conductors.
`In another aspect, the invention features a multiple con
`ductor cable including a plurality of elongate conductors
`produced by the process described above.
`The foregoing and other objects, aspects, features, and
`advantages of the invention will become more apparent from
`the following drawings, description, and claims.
`BRIEF DESCRIPTION OF THE DRAWINGS
`The objects and features of the invention can be better
`understood with reference to the drawings described below.
`The drawings are not necessarily to Scale, emphasis instead
`generally being placed upon illustrating the principles of the
`invention.
`FIG. 1 is a schematic overview of an embodiment of the
`system of the invention that shows the relationships of the
`components used in manufacturing a multiple conductor
`electrical cable according to the principles of the invention.
`FIGS. 2A-2F are different views of an embodiment of the
`invention in the form of a rotating die.
`FIG. 3 shows a cross section of a multiple conductor
`electrical cable of the prior art.
`FIG. 4 shows a cross section of a multiple conductor
`electrical cable manufactured according to the principles of
`the invention.
`FIG. 5 shows a comparison of the results of testing
`multiple conductor electrical cable made according to the
`principles of the invention and using manufacturing methods
`that do not employ the principles of the invention.
`DETAILED DESCRIPTION
`One of the least understood characteristics of paired
`cables is crosstalk because croSStalk depends on many
`variables. A great deal of attention is paid to the individual
`pairs in a cable, with respect to lay length and variation of
`lay length, but little attention is paid to the Overall geometry
`of the cable lay-up. This is due in part to the relatively long
`cable lay and the method in which the twisted pairs are layed
`up. It becomes very difficult to maintain a specific geometry
`that allows for equal center-to-center spacing of the indi
`vidual pairs. This center-to-center spacing is one of the
`characteristics that are critical to achieving enhanced
`crosstalk performance. In addition to difficulty in establish
`ing optimal spacing, degradation of the geometry can occur
`when the cable is payed off over a number of sheaves prior
`to being insulated, resulting in increased croSStalk.
`In Overview, the present invention includes in one
`embodiment a device that brings the geometry of the pairs
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`closet to the desired center-to-center Spacing to provide
`improved crosstalk performance. The device in one embodi
`ment is comprised of a rotatable die with four holes there
`through. The die is Set into a bearing. The bearing assembly
`is then Set into a holder designed to fit a core-tube of a
`jacketing crosshead, or otherwise to allow the cable that is
`manufactured to be provided with a sheath. The four pairs
`that are included in the cable are then Sequentially threaded
`through the holes in the dies and then through the crosshead
`and are tied to a lead cable. A hole is Strategically placed in
`the bearing holder to allow for the insertion of a rip cord.
`This assembly is placed in the back of the crosshead core
`tube and the insulating process begins. AS the cable is being
`pulled through the rotating die, the lay of the cable is opened
`up and Subsequently closes. Soon after exiting the die. The
`procedure allows for the necessary adjustments to the geom
`etry of the pairs. The croSStalk parameter of the cable
`manufactured according to the principles of the invention is
`optimized.
`Referring to FIG. 1, a schematic overview of an embodi
`ment of the system 100 of the invention is presented that
`shows the relationships of the components used in manu
`facturing a multiple conductor electrical cable 110. In the
`exemplary embodiment shown, the multiple conductor elec
`trical cable 110 is constructed from four strands 120, 122,
`124, and 126 that are delivered from respective sources,
`Such as reels 130, 132,134, 136. The strands 120, 122, 124,
`and 126 can be electrical conductors of different types, Such
`as individual wires, Some of which may be insulated and
`Some of which may not be insulated, or they can be multiple
`conductors including insulated wires. The strands 120, 122,
`124, and 126 can be a plurality of the same type of
`conductor. In one embodiment, the strands 120, 122, 124,
`and 126 are twisted pairs of insulated wire. AS is known in
`the art, the number of twists per unit length of Strand may be
`different for different strands 120, 122, 124, and 126. The
`exemplary embodiment depicts an example in which four
`strands 120, 122, 124, and 126 are employed to make a
`multiple conductor electrical cable 110.
`The multiple conductor electrical cable 110 of the exem
`plary embodiment can be used for connections between
`computers or other electronic devices that communicate at
`high Speed. In other embodiments, the communication
`requirements may Suggest the use of a cable having fewer
`than four twisted pairs, for example, the connection of a
`telephone to a Switching System. Alternatively, the require
`ments may Suggest the use of a cable having more than four
`twisted pairs, for example, in providing wiring to be
`installed at the time of construction of a building, Such that
`the wiring allows for a variety of potential uses and com
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`munication configurations. It is possible to employ the
`Systems and methods of the invention using a broad range of
`Strands. In one embodiment, each Strand can be a twisted
`pair, and any convenient number of Strands may be
`employed to make a multiple conductor electrical cable 110.
`AS an example, it is possible to produce a multiple conductor
`electrical cable using the principles of the invention in which
`a first cable having, for example, Six Strands of twisted pair
`conductors is produced. In this example, the first cable can
`then be used as a central core in a further iteration of the
`process, wherein a Second layer of Strands is applied to the
`Six Strand core cable, for example, a layer having an addi
`tional 12 Strands. By repeating the proceSS in a Suitable
`Stepwise manner, a cable having a desired number of Strands
`can be produced. In Some embodiments, the Strands can be
`Single conductors or multiple conductors. The number of
`conductors that any individual Strand may include can be the
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`same as or different from the number of conductors that
`another Strand may include. Cables having tens or hundreds
`of Strands can be produced using the principles of the
`invention.
`In the exemplary embodiment depicted in FIG. 1, the
`strands 120, 122, 124, and 126 pass through apertures
`defined in a rotatable body 146 of rotatable alignment die
`140, with each strand 120, 122, 124, and 126 passing
`through its own aperture 148. The apertures 148 defined in
`the surface of the rotatable body 146 of rotatable alignment
`die 140 are oriented so as to permit each strand 120, 122,
`124, and 126 to pass through the rotatable body 146 of
`rotatable alignment die 140 in a direction oriented within 45
`degrees of the rotation axis 149 of the rotatable body 146 of
`rotatable alignment die 140. The rotatable body 146 of
`rotatable alignment die 140 is held rotatably in a fixing collar
`142. The fixing collar 142 can be attached, for example, by
`an adjustable bracket that allows the fixing collar 142 to be
`adjustably positioned relative to the Supply of strands 130,
`132, 134, and 136 and relative to a binder applicator 150.
`The strands 120, 122, 124, and 126 are aligned to come
`together at a controlled location 155 beyond the rotatable
`body 146 of rotatable alignment die 140. The multiple
`conductor electrical cable 110 can be caused to rotate about
`its elongated axis by the action of a rotation motor 112,
`which can be an electric motor or the like connected to the
`multiple conductor electrical cable 110 by a drive system.
`Torque or angular Velocity can be imparted by the rotation
`motor 112 to at least one of the strands 120, 122, 124, and
`126 that make up the multiple conductor electrical cable 110
`along the elongated axis of the strand 120, 122, 124, and
`126. The multiple conductor electrical cable 110 is also
`caused to traverse along its elongated axis, or equivalently,
`translate along its length from the controlled location 155 to
`a take-up reel 160, at a controlled velocity by the action of
`a translation motor 162. For example, the translation motor
`162 can be connected to rotate a take-up reel 160 that
`collects the multiple conductor electrical cable 110 as the
`multiple conductor electrical cable 110 is being produced.
`Other mechanisms to impart linear motion to a strand 120,
`122, 124, and 126, or to a multiple conductor electrical cable
`110, are known and may be employed to cause the multiple
`conductor electrical cable 110 to translate to a take-up
`location at a controlled Velocity. In Some embodiments, the
`rotation motor 112 and the translation motor 162 may be the
`Same motor and the two motions may be produced by the
`connection of multiple power trains to the motor, which
`operates at a controlled Speed. Power trains that use adjust
`able gearing or other Speed control mechanisms can be used
`to generate the desired rotational Velocity and translational
`velocity for the multiple conductor electrical cable 110.
`In Some embodiments, a binder may be applied to bind the
`strands 120, 122, 124, and 126 of the multiple conductor
`electrical cable 110 into an assembly in which each strand
`120, 122, 124, and 126 is held in the mutual mechanical
`alignment imparted to it by passing through the apertures
`148 of the rotatable body 146 of rotatable alignment die 140.
`In one embodiment, the binder can be a material that can be
`softened thermally. In another embodiment the binder can be
`a thermosetting material. In Some embodiments, the binder
`can be a mechanical binder Such as a helical sheath, a sheath
`having a longitudinal slit, a Series of wrappings, Such as
`tie-wraps, or the like. The binder can be made from materials
`that have desirable properties, Such as materials that are
`electrical insulators, materials that are capable of Serving as
`a Faraday cage, materials that are fire resistant, materials
`that are color coded to make identification of the product
`easy, materials that have a low coefficient of friction, and the
`like.
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`Abinder applicator 150 is positioned to deliver the binder
`to the multiple conductor electrical cable 110 substantially at
`controlled location 155 where the strands 120, 122, 124, and
`126 come together to form the multiple conductor electrical
`cable 110. The precise position of application of the binder
`relative to the rotatable alignment die 140 and the controlled
`location 155 can be adjusted by positioning the binder
`applicator 150 on an adjustable bracket or the like. The
`binder can be applied to the multiple conductor electrical
`cable 110 by flowing the binder through a tube 152 con
`nected to the applicator 150. Alternatively, the binder can be
`applied by passing the multiple conductor electrical cable
`110 through apertures in the binder applicator 150, so that
`the motion of the multiple conductor electrical cable 110
`causes the binder to be applied to the cable 110. AS is known
`in the control arts, one or more controllers, Such as a
`computer, a programmable controller, or manually adjust
`able controls can be used to control the manufacturing
`proceSS.
`FIGS. 2A through 2F illustrate the design and construc
`tion of an embodiment of the rotatable alignment die 140 in
`different views.
`FIG. 2A shows the rotatable alignment die 140 in
`exploded view, with a fixing collar 142 at the leftmost
`position, a ball or roller bearing 144 in the middle position,
`and a rotatable body 146 in the rightmost position. A rotation
`axis 149 is shown, which is the axis of rotation of the ball
`or roller bearing 144 and of the rotatable body 146. The
`application of torque, or rotational force, to at least one of
`the strands 120, 122, 124, and 126 passing through the
`rotatable body 146 of rotatable alignment die 140 will cause
`the rotatable body 146 to experience a torque because none
`of the strands 120, 122, 124, and 126 passes through the
`rotatable body 146 along its rotation a