MXPA00009352A - Twisted pair cable - Google Patents

Abstract

The invention relates to a foamed twisted pair cable (23) which is exceptionally suitable for high frequency signal transmission. One embodiment provides a twisted pair cable having a center-to-center conductor spacing at any point along a 305 M (1000 ft) cable that varies±0.03 times the average of the center-to-center conductor. Another embodiment provides a twisted pair cable having an impedance of 90 to 110 ohms with a tolerance of±5%of an average impedance. The preferred twisted pair cable has their dielectrics joined along the entire length thereof.

Description

DOUBLE DRIVER CABLE RETURNED FIELD OF THE INVENTION The present invention relates to twisted double lead wires, which can be used in high frequency applications and more particularly, the present invention relates to high frequency twisted double lead wires, which have a pair of insulated conductors with each insulated conductor, which it has a first layer of insulating foam surrounding the conductor, and a second insulating layer surrounding the first layer.

BACKGROUND OF THE INVENTION In the past, twisted double lead wires were used in applications where information speeds (data) reached an upper limit of approximately 20 ilobits per second. Recent advances in the technology of installing conductors and equipment of physical elements comprising the installation have pushed the applications of double twisted cable to approximately several thousand megabits per second to the upper limit. Technological advances of the twisted double conductor have focused mainly on bringing the end of the REf: 123331 interference from an adjacent channel. Both the U.S. patent 3,102,160 and the patent 4,873,393 teach the importance of using two-conductor lines, which are twisted with different wiring lengths, from integral assemblies of the wiring lengths of other conductors coupled within the cable. This is done to minimize the electrical coupling between the coupled conductors. The U.S. patent 5,015,800 focuses on another important problem of maintaining a controlled impedance along the transmission line. This teaches how the impedance can be stabilized by the elimination of air gaps around a twisted double conductor through the incorporation of the use of a dielectric network, which have outer layers attached after insulation, the conductors twist. When two or more lines of two conductors of different average impedance are connected together to form a transmission line (often called a channel), part of the signal will be reflected at the plug-in point (s). Reflections due to unequal impedance eventually cause problems with signal loss and tracking error (fluctuation in a transmission signal). The previous efforts, to control the spacing of the conductor have been completely, for the purposes of stabilizing the capacitance within a cable. It is well known in the industry that using a cable with uniform capacitance between its two conductor lines has the advantage of reducing the interference of an adjacent channel. The U.S. patent 3,102,160 explains how an equal and uniform capacitance can be carried out along a transmission line, simultaneously extruding the dielectric, by means of two conductors. However, U.S. 3,102,160 did not recognize the problems encountered with the impedance inequality at high frequencies. The impedance of the cable was of little importance as long as the capacitance of each line of two conductors within the cable was relatively uniform. The problem is that different cables can have uniform capacitances between their respective lines of two conductors, and still have different averages of impedances. Another problem with the U.S. patent 3,102,160 is with respect to the separation of the insulated conductor. In order for the two conductor lines to be used with current LAN systems (local area network) and to connect the equipment of physical elements comprising the installation, the isolated insulated conductors must have the ability to separate from each other by at least 2.5 cm (1 inch), along the length of the line of two conductors. The prior art does not provide means for the separation of the two isolated insulated conductors.

BRIEF DESCRIPTION OF THE INVENTION According to the first dielectric layer, which is a dielectric foam or cellular dielectric, it is an object of this invention to provide a double twisted conductive cable, having two conductors, at least two dielectric layers surrounding each conductor, the conductors and the corresponding dielectric layers are substantially twisted along the length of the cable, to provide the twisted double conductor cable having a center-to-center distance between the twisted conductors, which varies over any length of 305 m (1000 ft) 60.03 times an average distance from center to center with the average center-to-center distance, which is the average of at least 20 distance measurements taken at least 6.1 m (20 ft) apart from three randomly selected 305m (1000 ft) twisted cables of the same size, taken from the same section or from three successive sections. It is a further object of this invention to provide a twisted double conductor cable having two conductors, a dielectric layer surrounding each conductor, the conductors and corresponding dielectric layers twisted substantially along the length of the cable, to provide the cable double twisted conductor having an impedance of about 90 to 110 ohms over any length of 305 m (1000 ft), when measured at frequencies of about 10 MHz to about 200 MHz, the impedance is within the impedance tolerance of 6 5% of an average impedance, the average impedance is: a. an average of at least one impedance measurement in each of at least twenty twisted double lead wires of the same size 305 m (1000 ft), taken from the same span or, b. an average of at least one impedance measurement of each of the twenty twisted double lead wires of the same size 305 m (1000 ft) selected at random, taken from three successive spans separated with each span, which is at least separated 24 hours one from the other. c. a selection of a twisted double conductor cable from 91.4 m-305m (300 to 1000 ft) and taking at least 200 impedance measurements on the twisted double lead wire, with at least 200 impedance measurements that are between 10 MHz and 200 MHz, taken in increments of less than 0.5 MHz. The present invention and advantages thereof become more apparent in consideration of the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a side view of a twisted double conductor cable, according to a preferred embodiment of the invention. Fig. 2 is an enlarged cross-section, taken along lines 2-2 of Fig. 1. Fig. 3 is a cross-section similar to Fig. 2 of another embodiment of the present invention. Fig. 4 is an enlarged cross sectional view of another embodiment of a twisted double conductor cable.

DETAILED DESCRIPTION OF THE INVENTION Figures 1 and 2 show one embodiment of the twisted double lead cable 10, which can be used in high frequency applications, the wire 10 has two solid, stranded or hollow conductor wires 12 and 13. The conductors are solid metal, a plurality of wires metallic, an appropriate conductor of fiberglass, a metal constituted by superposed layers of the same one. Each conductor 12 and 13 were surrounded by the respective cylindrical dielectric or insulator 14 and 15. Each of the conductors 12 and 13 are centrally disposed therein, and in this manner substantially concentric with the corresponding insulators 14 and 15. The conductors 12 and 13 they may, if desired, adhere to any degree against the inner walls of their respective insulator, by any appropriate means, such as bonding, by heat or adhesives to prevent relative rotation between conductors and insulators. As shown in Fig. 2, the insulator 14 has an inner or first layer of dielectric foam or cellular dielectric 14a surrounding the conductor 12, and an outer or second layer of dielectric 14b surrounding the first layer 14a. The insulator 15 has an inner or first layer of dielectric foam or cellular dielectric 15a surrounding the conductor 13 and an outer or second layer of dielectric 15b surrounding the first layer 15a. The cable 10 has a common insulator for both conductors 12 and 13, as shown in Fig. 2, where the insulators 14a and 15a, and the insulators 14b and 15b are integral with each other and are joined together along their lengths in any appropriate way. As shown, the joining means is with an integral fabric 18, which extends from the diametral axis of each insulator. The tissue extension 19 is between the range of from approximately 6.35xl04 cm (0.00025 in) to approximately 0.381 cm (0.150 in). The thickness 21 of the fabric is also in the range of from about 6.35xl04 cm (0.00025 in) to about 0. 381 cm (0.150 in). The thickness of the fabric is preferably smaller than the thickness 22 of both dielectric layers. The - extension of the fabric is preferably less than the thickness 22 of the dielectric layers. The diameter (traditionally expressed in size AWG (American wire gauge)) of each of conductors 12 and 13, are preferably between about 18 to about 40 AWG. The conductors 12 and 13 are preferably metallic conductors and can be constructed of any suitable metallic material, such as solid copper or wire, metallized substrate, silver, aluminum, steel, alloys or in combinations thereof. The dielectric may be an appropriate material used in the insulation of cables, such as foamed and non-foamed polyvinyl chloride, polyethylene, polypropylene or fluoro copolymers (such as Teflon, which is a registered trademark by DuPont), fluoropolymers ( such as HALAR, which is a trademark of Ausimont) cross-linked polyethylene, rubber, etc. Many of the insulators may contain a flame retardant. It is preferred that the first dielectric or cellular dielectric foam layer 14a and 15a be of the same material as the second dielectric 14b and 15b, which may be a partially foamed or non-foamy material. The thickness 22 of the dielectric layers 14 and 15 are in the range of from about 6.35xl04 cm (0.00025 in) - to about 0.381 cm (0.150 in). Double drivers, surrounded by the dielectric bonded layers 14 and 15 are twisted to form a twisted double conductor wire. The variation in the distance between the centers of the adjacent conductors, will later be referred to as the distances from center to center, along the twisted double conductor cable are very small. The center-to-center distance d, at any point along the twisted double conductor cable, does not vary by more than 60.03 times the average center-to-center distances measured along the twisted parallel cable, with the average that was calculated randomly selecting three twisted double lead wires of the same size 305 m (1000 ft), of the same span or three successive runs in three separate days, taking 20 measurements on each wire to at least 6.1 m (20 ft) apart, and calculating the average of all the measurements. Fig. 3 illustrates another embodiment of the invention, wherein the joining means are by a solid integral fabric 18a which is formed by the second layers 14b and 15b. Since the dimensions are within the ranges presented above, the same numbering is used. In another embodiment of the invention, the double twisted conductor cable has only one insulator in each conductor. Foam insulators and twisted double conductor cable are substantially bonded or bonded together along their total length, by an appropriate adhesive or adjacent dielectric layers (insulation) are bonded together, causing contact of the material while the foam dielectrics they are at elevated temperatures and subsequently cooled, to provide a bonded cable that has no adhesive. The non-adhesive bond provides a common integral dielectric layer for the two conductors. The conductors have an AWG size of from about 18 to about 40. The thickness of the dielectric insulator is from about 6.35xl04 cm (0.00025 in) to about 0.381 cm (0.150 in). The contact between the two bound foam dielectrics is such that the thickness is preferably less than the thickness of one of the dielectric layers. The dielectric layers are foam dielectrics of the same materials as the dielectrics 14a and 15a. The bond at 24 or tissues 18 and 18a are such that the dielectric layers can be separated and remain intact with a force of no more than 5 lbs. An adhesion force is provided between the dielectrics of between 0.1 to 5 lbs. Force, and preferably between 0.11 and 1.13 kg. Force (0.25 to 2.5 lbs. Force). When used in temporary connection panels, blocks, and connectors are drilled, it becomes necessary for the two insulating conductors to segregate from one another. The width or extension can be increased up to an inch or more. With two-wire cable type technology, the two conductors can not be detached uniformly-a distinct disadvantage when compared to the invention. It should also be noted that many connectors, such as the commonly used RJ-45 plug, require that individual insulated conductors be uniformly enclosed. With the invention, once the individuals detach, they will retain their roundness independent of each other. Any number of twisted double lead wires may be incorporated within a wrap or an unshielded wire with an optional metal shield under the cladding, or applied above each twisted double lead or groups of twisted double conductors. Cables 10, 10a and 23 are provided for relatively error-free transmissions, within the frequencies most used by LAN (local area network) systems. The impedance of the cable is controlled by two main factors; the spacing of the conductor and the dielectric between the conductors. The more uniform the spacing of the conductor and the dielectric, the more uniform the impedance will be. An important feature of the present invention is that the twisted double lead wires 10, 10a and 23 each have center-to-center distances d, measured between the centers of the adjacent conductors that are 60.03 times the average of d, with the variation which is not any more than this, at any point along a twisted double conductor cable of 305 m (1000 ft). To measure the average of d in the twisted double lead wires, at least three and preferably 20 wire samples of the same size 305 m (1000 ft), of the same stretch or at least three separate successive stretches were randomly selected with each one of the successive sections, occurring in a day or a separated period of 24 hours. The average d is calculated by taking at least 20 measurements on each 305 m (1000 ft) cable, with each measurement taken at least 6.1 m (20 ft) apart, all the measurements taken are added and the measurements added by the total number of measurements taken. All measurements taken from d fall within the tolerances of 60.03 times the average of d. If these do not fall, the twisted double conductor cables of those sections are discarded. The following exemplifies 4 twisted double conductors attached to 24 AWG wires, which were prepared and measured and which do not have the required center-to-center distance d of the present invention. The wires have an average center-to-center 0.089 cm (0.0353 in) driver spacing. This average d in inches is taken from three 305 m (1000 ft) cable lengths selected at random, taken from three successive sections in three separate days, with 20 measurements taken in at least 20 intervals of 6.1 m (20 ft) in each cable. The results are shown in the following table, where all measurements are in inches.

Sample Cable l (dl Cable 2 < d) Cable 3 (d). CM n CM H CM n 1 .0902 (.0355) .0924 (.0364) .0874 (.0344) 2 .0894 (.0352) .0935 (.0368) .0864 (.0340) 3 .0909 (.0358) -0925 (.0364.) .0866 (.0341) 4 .0897 (.0353) .0907 (.0357) .0879 (.0346) .0884 (.0348) .0890 (.0352) .0874 (.0344) and .0864 (.0340) .0904 (.0356) .0884 (.0348) 7 .0881 (.0347) .0904 (.0356) .0894 (.0352) .0886 (.0345) .0912 (.0359) .0876 (.0345). 9 .0902 (.0355) .0932 (.0367) .0866 (.0341) .0919 (.0362) .0919 (.0362) .0881 (.0347) 11 .0932 (.03 £ 7) .0930 (.0366) .0894 (.0352) 12 .0922 (.0363) .0922 (.0363) .0889 (.0350) 13 .0899 (.0354) .0904 (.0356) .0904 (.0356) 14 .0884 (.0348) .0881 (.0347) .0899 (.0354) .0876 (.0345) .0902 (-0355) .0891 (-0351) ÍS .0874 (-0344) .0894 (.0352) .0876 (.0345) 17 .0891 (.0351) .0912 (.0359) .0874 (.0344)? A .0904 (.0356) .0922 (.0363) .086.6 • (.0341) 19 .0891 (.0351) .0930 (.0366) .085.3 (.0336) .0881 (.0347) .0935 (.0368) .0851 (.0335) TOTAL 1.7B94 (.7045) 1.8273 (.7194) 1.7556 (.6912) Cable Totals 1 + 2 + 3 divided by 60 - 0B97 (.0353") In this case, the range of acceptable d is from 0.0869 to 0.0924 cm (0.0342 to 0.0364 in), ie 0.0897 cm (0.0353 in) (the average) 60.0279 (0.0011 in) 0.03 x 0.0897 (0.0353)) Since in the previous example there are measurements outside this tolerance in each of the cables, all twisted double conductor cables from each of these sections would be rejected. measuring the amount of structural variation in a cable, sending a signal along the transmission line (via cable) and measuring the amount of reflected energy back in the direction of the test devices. a maximum value at particular frequencies (often referred to as' stress points within the wiring industry.) This is the result of a cylindrical variation in the construction, which equals the wave - cyclical (or frequency) propagating under the cable.

The more return energy, the less energy is available at the other end of the cable. The actual reflected energy can be predicted by the stability of the impedance of the transmission line. If an impedance signal of 100 ohm is sent to the cable, any part of the cable that is not exactly 100 ohm will cause reflection. Therefore, a combined alternative and / or feature of the twisted two conductor lines 10, 10a and 23 is that each double twisted conductor wire has an impedance of from 90 to 110 ohms, when measured at high frequencies of approximately 100 MHz up to approximately 200 MHz with a tolerance not greater than 65%. Tolerance is determined by multiplying an average impedance by 60.05 times. The average impedance is calculated by taking the impedance measurements between approximately 10 MHz to approximately 200 MHz, in random sampling of twisted double lead wires of the same size 305 m (1000 ft), with at least one impedance measurement in each of at least twenty (20) randomly displayed 'double twisted conductors cables 305 m (1000 ft) taken from the same section. Another average impedance, which would not be accepted, would be taking at least one measurement of impedance in at least twenty twisted double stranded wires of the same size 305 m (1000 ft) selected at random, taken from three successive spaced apart sections at minus three separate days. Twisted double conductors of 305 m (1000 ft) are rated for an impedance of approximately 90 to approximately 110 ohms, when measured at a frequency between 10 MHz and 200 MHz. As noted above, the acceptable twisted double conductor of 305 m (1000 ft) will have an impedance at any frequency between 10 MHz and 200 MHz that varies no more than 60.05 times the average impedance. For example, if the average impedance is 96.2, there is no impedance measurement between 10 MHz and 200 MHz that can be greater than 101.0 ohms (96.2 + 4.8 [96.2x0.05]) or less than 91.4 ohms (96.2-4.8 [96.2-4.8]). 96.2x0.05]). Still another average impedance used in the present invention is calculated, taking at least 200 impedance measurements in a twisted double conductor of 91.4 m-305 m (300-1000 ft) with at least 200 impedance measurements, which are taken in increments of less than 0.5 MHz, if any of the Impedance measurements of between 10 and 200 MHz vary by more or less than 0.05 times the average impedance in the single cable cable stretch is not acceptable. The average impedance is calculated in the usual way, i.e. adding all the impedance measurements and dividing the total by the number of impedance measurements. The drag apart from the twisted double lead wires for at least one inch, leaves the insulator 14, 15 and 27, 28 substantially intact, by means of the separate portion and does not disturb the twisting. The cables 10, 10a and 23 each can be separated without causing wringing fraying and separation. Adhesion strength is determined by holding an insulated conductor and pulling the other insulated conductor. Adhesion strength is preferred between 0.25 and 2.5 lbs. Force for twisted wires 10, 10a and 23 that substantially leave the insulator 14 and l5 and 27 and 28 remain substantially intact. The twisted double lead wires 10, 10a and 23 are prepared by simultaneously extruding the insulators by means of two wires and subsequently adhering the two insulated conductors via bonding, by weaving, or other appropriate means. The insulated conductors that have been joined together are twisted to produce the desired number of turns per length of attached wire rope. The twisted wire cable 23 is preferably prepared by the side-by-side protective layer of the two conductors, first with the dielectric foam or cellular dielectric, and then the dielectric or cellular dielectric foam is appropriately sized to the desired diameter, the dielectric foam or the dielectric foam. designed cellular dielectric is covered with the second dielectric, then the two insulated conductors are joined before the wires are wound, an adhesive is optionally used to join the two covered wires, and then the two wires are joined, twisting the isolated wires attached to the wires. the desired return. The above description is for illustration purposes only, and I do not know how to limit the scope of the agreed protection of this invention. The scope of protection is to be measured by the following claims, which must be interpreted as broadly as the inventive contribution allows.

It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it relates.

Claims (20)

1. CLAIMS Having described the invention as above, the content of the following claims is claimed as property 1. A twisted double conductor cable, characterized in that it contains: two conductors, a first and second dielectric layer surrounding each conductor, the first dielectric layer is a dielectric foam or cellular dielectric, the second dielectric layer surrounds the first dielectric layer, the conductors and the corresponding dielectric layers twist substantially, along the length of the cable to provide the double twisted conductor wire, the double twisted conductor wire has a center-to-center distance between the two twisted conductors that varies over any length 350 m (1000 ft) of 60.03 times an average center-to-center distance with an average center-to-center distance that is the average of at least 20 distance measurements, taken at least 6.1 m (20 ft) apart from the three twisted cables of the same size 305 m (1000 ft) selected at random, taken from the same stretch or taken from at least three successive sections separated, with each section that is in a separate day. The cable of claim 1, characterized in that the first and second dielectric layers are made of the same dielectric composition, with the first dielectric layer being a dielectric or cellular dielectric foam, and the second dielectric layer that is not a dielectric foam or cellular dielectric. The cable of claim 2, characterized in that each conductor has a diameter of from about 18 to about 40 AWG, and the first and second dielectric layers of each conductor have a combined thickness in the range of from about 6.35xl04 cm (0.00025) in) to approximately 0.381 cm (0.150 in) and the second dielectric layer of each conductor joins along the length of the second dielectric layers. The cable of claim 3, characterized in that the dielectric layers of each conductor are joined together by a network extending substantially along the length of each of the conductors. The cable of claim 4, characterized in that the fabric extends from the diametrical axes of the dielectric layers. The cable of claim 4, characterized in that the fabric has a thickness and an extension, which are smaller than the thickness of the first and second dielectric layers. The cable of claim 6, characterized in that each of the conductors is fixed within the first dielectric layers, so that each of the conductors is incapable of rotating, within the first dielectric layers. 8. A twisted double conductor cable characterized in that it contains: two conductors, a first and second dielectric layer surrounding each conductor, the first dielectric layer is a dielectric or cellular dielectric foam, the second dielectric layer surrounds the first dielectric layer, the conductors . and the corresponding dielectric layers are twisted substantially, along the length of the cable to provide the twisted double lead wire, the twisted double lead wire has over any length of 305 m (1000 ft), an impedance of about 90 to 110 ohms , when measured at frequencies from about 10 MHz to about 200 MHz, the impedance being within an impedance tolerance of 65% of an average impedance, the average impedance is: a. a percentage of at least one impedance measurement in each of at least twenty twisted double conductors of the same size 305 m (1000 ft), taken from the same span, or, b. a percentage of at least one impedance measurement of each of the twenty twisted twin conductors of the same size 305 m (1000 ft) selected at random, taken from three separate successive sections, with each section that is at least 24 hours apart from each other, or, c. a selection of a double twisted conductor cable, from 91.4 m to 305 m (300 to 1000 ft), and which takes at least 200 impedance measurements in the twisted double conductor, with at least 200 impedance measurements that is between 10 MHz and 200 MHz, taken in increments of less than 0.5 MHz. 9. A twisted double conductor cable, characterized in that it contains: two conductors, a first and second dielectric layer, surrounding each conductor, the first dielectric layer is a foam dielectric or cellular dielectric, the second dielectric layer surrounds the first dielectric layer, the conductors and the corresponding dielectric layers twist substantially along the cable to provide the double twisted conductor wire, the double twisted conductor wire has over any length of 305m (1000 ft), an impedance of approximately 90 to 110 ohms when measured at frequencies from approximately 10 Mhz to approximately 200 MHz, the impedance is within an impedance tolerance of 65% of an average, the average impedance is obtained by selecting a twisted double conductor of twenty consecutive twisted conductors of 305 m (1000 ft), and taking at least 200 impedance measurements in the double twisted conductor, with at least 200 impedance measurements that are between 10 MHz and 200 MHz, taken in increments of less than 0.5 MHz. The cable of claim 8, characterized in that each conductor has a diameter of from about 18 to about 40 AWG, and the first and second dielectric layers of each conductor have a combined thickness in the range of approximately 6.35xl04 to 0.381 cm ( 0.00025 to approximately 0.150 in) 11. The cable of claim 10, characterized in that the dielectric layers of each conductor are joined together by a fabric that extends substantially along the length of each of the dielectric layers. 12. The cable of claim 11, characterized in that the fabric extends from the diametrical axes of the dielectric layers. 13. The cable of claim 12, characterized in that the fabric has a thickness and extension, which are smaller than the diameter of the conductors. 14. The cable of claim 13, characterized in that each of the conductors is fixed within the first dielectric layers, so that each of the conductors is unable to rotate within the first dielectric layers. The cable of claim 9, characterized in that the twisted double lead wire has a center-to-center distance at any point along the twisted double lead wire, which does not vary by more than 60.03 of an average distance from center to center , the average center-to-center distance, is an average of at least 20 center-to-center distance measurements in each of at least three twisted double stranded wires of the same size 305 m (1000 ft) selected at random, each Measurement is taken at least 6 m (20 ft) apart, and taken from the same stretch or from three separate sections in three successive days. The cable of claim 2, characterized in that the twisted double lead wire has an impedance of about 90 to 110 ohms when measured at frequencies of about 10 MHz to about 200 MHz, the impedance is within an impedance tolerance of 65. % of an average impedance, the average impedance is: a. an average of at least one impedance measurement, in each of at least twenty twisted double conductors of the same size 305 m (1000 ft) taken from the same span, or b. an average of at least one measurement of • impedance of each of the twenty twisted twin conductors of the same size 305 m (1000 ft) selected at random, taken from three separate successive sections with each section that is at least 24 hours apart from each other, or c. a selection of a double twisted conductor from 91.4 to 305 m (300 to 1000 ft), and which takes at least 200 impedance measurements in a twisted double conductor with at least 200 impedance measurements that are between 10 MHz and 200 MHz, taken in increments of less than 0.5 Mhz. The cable of claim 16, characterized in that the second dielectric layer of each conductor is joined together along the length of the second layers • Dielectric The cable of claim 2, characterized in that the second dielectric layer of each conductor is joined together along the length of the second dielectric layers. 19. The cable of claim 9, characterized in that the first and second dielectric layers are made of the same dielectric composition, with the first dielectric layer being a dielectric foam or cellular dielectric and the second dielectric layer that is not a dielectric foam or cellular dielectric . The cable of claim 9, characterized in that the second dielectric layer of each conductor is joined together along the length of the second dielectric layers.