A conductor assembly and a cable assembly

Abstract

The cable assembly 100 comprises an electrical conductor formed of a plurality of strands110-1, 110-2 and an insulating sleeve 120 surrounding the electrical conductor. Each of the plurality of strand

Description

Field

[0001] The present disclosure relates generally to a conductor assembly for use, in particular, in a cable assembly. Background

[0002] Electrical cables, which comprise one or more conductors, can be used to transmit data and / or power from one point to another. Ideally, this transmission occurs without loss or distortion. Summary

[0003] Aspects of the present disclosure are defined in the accompanying independent claims . Overview of disclosure

[0004] A conductor assembly is disclosed.

[0005] The conductor assembly comprises an electrical conductor formed of a plurality of strands and an insulating sleeve surrounding the electrical conductor.

[0006] Optionally, the strands and / or the insulating sleeve are formed and / or arranged to dampen vibrations of the strands.

[0007] Optionally, each of the plurality of strands has a respective cross-sectional area of less than 0.1 square millimetres.

[0008] Optionally, the plurality of strands are slack within the insulating sleeve. Optionally, the plurality of strands are slack within the insulating sleeve when the insulating sleeve is unwound (or 'not wound'), or not wound on a drum or bobbin, or not coiled. Optionally, the plurality of strands are slack within the insulating sleeve at least when the insulating sleeve is unwound (or 'not wound' ), or not wound on a drum or bobbin, or not coiled.

[0009] Optionally, no more than 70% of a respective length, within the insulating sleeve, of each one of the plurality of strands is in contact with any others of the plurality of strands. Optionally, in a (or preferably any) portion of the insulating sleeve having a length of at least 30mm (preferably, at least 50mm, more preferably, at least 100mm), no more than 70% of a respective length, within the insulating sleeve, of each one of the plurality of strands is in contact with any others of the plurality of strands.

[0010] Optionally, no more than 10% of a respective length, within the insulating sleeve, of each one of the plurality of strands is in contact with any others of the plurality of strands.

[0011] Optionally, contact, within the insulating sleeve, between the one of the plurality of strands and the any others of the plurality of strands is longitudinally substantially evenly distributed.

[0012] Optionally, contact, within the insulating sleeve, between the one of the plurality of strands and the any others of the plurality of strands is longitudinally evenly distributed.

[0013] Optionally, at least an inner portion of the insulating sleeve is made of a material having one or both of a Shore 00 hardness (or 'hardness on a Shore 00 scale', or 'Shore hardness on a 00 scale' , or 'Shore hardness on a Shore 00 hardness scale' , or 'Shore 00-scale hardness', or 'durometer hardness measured on a Shore 00 scale') of at least 83 or a loss factor (or 'tan delta', or 'tan 5', or 'flexural loss factor') of no more than 0.2. Optionally, the plurality of strands are not bonded to the insulating sleeve.

[0014] Optionally, at least an inner portion of the insulating sleeve is made of a damping material having one or both of a Shore 00 hardness of less than 83 and a loss factor (or 'tan delta', or 'tan 5', or 'tan(S)', or 'flexural loss factor', or 'mechanical energy loss factor') greater than 0.2. Optionally, the plurality of strands are not bonded to the insulating sleeve or, optionally, the plurality of strands are bonded to the insulating sleeve.

[0015] Optionally, the damping material consists of solid, granular or gel materials, or a combination thereof.

[0016] Optionally, the damping material is an elastomer.

[0017] Optionally, the damping material is a polyolefin.

[0018] Optionally, the damping material is: polyisobutene, nitrile rubber, thermoplastic polyurethane, polychloroprene, silicone, Akton®, Hydrin® DP5245, Sorbothane®, polyisoprene, styrene-butadiene rubber, polybutadiene, acrylonitrile-butadiene rubber, isobutyleneisoprene rubber, ethylene propylene rubber, ethylene-propylene-diene monomer rubber, a polysulfide such as Thiokol®, polydimethylsiloxane, a fluoroelastomer, polyacrylate, chlorinated polyethylene, chlorosulfonated polyethylene, styrene-isoprene-styrene (SIS) block copolymer, styrene-butadiene-styrene (SBS) block copolymer, a polypropylene blend, or a combination thereof.

[0019] Optionally, the damping material is polyisobutene (or 'polyisobutylene' ) .

[0020] Optionally, the plurality of strands are bonded to the damping material.

[0021] Optionally, the insulating sleeve comprises an inner layer made of the damping material and an outer layer made of a dielectric material.

[0022] Optionally, the damping material is a dielectric, damping material. Optionally, the insulating sleeve is made of the dielectric, damping material.

[0023] Optionally, a respective length of each of the plurality of strands within the insulating sleeve exceeds a length of the insulating sleeve by at least 0.5%. In other words, optionally, each of the plurality of strands has a portion that is within the insulating sleeve and that has a respective length, and that length is at least 1.005 times the length of the insulating sleeve.

[0024] Optionally, a respective length of each of the plurality of strands within the insulating sleeve exceeds a length of the insulating sleeve by at least 10%. In other words, optionally, each of the plurality of strands has a portion that is within the insulating sleeve and that has a respective length, and that length is at least 1.1 times the length of the insulating sleeve.

[0025] Optionally, a respective length of each of the plurality of strands within the insulating sleeve exceeds a length of the insulating sleeve by no more than 60%. In other words, optionally, each of the plurality of strands has a portion that is within the insulating sleeve and that has a respective length, and that length is no more than 1.6 times the length of the insulating sleeve.

[0026] Optionally, an average length of each of the plurality of strands within the insulating sleeve exceeds the length of the insulating sleeve by a total cable excess length factor (which is greater than 1). Optionally, in a (or preferably any) portion of the insulating sleeve having a length of at least 30mm, an average length of each of the plurality of strands within the insulating sleeve exceeds the length of the insulating sleeve by a segment excess length factor (which is greater than 1). Optionally, the segment excess length factor in any of the portions of the insulating sleeve varies between 50% and 200% or, preferably, 80% and 120%, of the total cable excess length factor.

[0027] Optionally, each of the plurality of strands is arranged within the insulating sleeve in a serpentine (or 'sinuous', or 'zigzagging', or 'meandering', or 'winding') manner.

[0028] Optionally, at least one of the plurality of strands is formed of a plurality of entwined sub-strands.

[0029] Optionally, the insulating sleeve is longitudinally slitted.

[0030] A cable assembly is disclosed. The cable assembly comprises at least one of the conductor assemblies described herein, and a sheath surrounding the at least one of the conductor assemblies.

[0031] Optionally, the cable assembly further comprises a first electrical connector and a second electrical connector at respective ends of the cable assembly.

[0032] Optionally, the at least one of the conductor assemblies comprises a plurality of the conductor assemblies. Optionally, the insulating sleeves of each of the plurality of the conductor assemblies are integrally formed with each other. Brief description of the drawings

[0033] Examples of the present disclosure will now be explained with reference to the accompanying drawings in which: Fig. 1 shows a key for the subsequent figures of the present disclosure . Figs. 2A, 2B, 2C, and 2D show a conductor assembly according to a first implementation. Fig. 3A shows a conductor assembly in which strands of the conductor assembly are in tension within an insulating sleeve. Fig. 3B shows a conductor assembly in which the strands are slack within the insulating sleeve. Fig. 3C shows a conductor assembly in which the strands are slack within the insulating sleeve and are mounted within a respective bung at each end of the insulating sleeve. Figs. 4A, 4B, 4C, 4D, 4E, and 4F show a conductor assembly according to a second implementation. Figs. 5A, 5B, 5C, 5D, 5E, and 5F show conductor assemblies according to the first implementation, in which the insulating sleeve has a first cross-sectional shape and is longitudinally slitted. Figs. 6A, 6B, 6C, 6D, and 6E show conductor assemblies according to the first implementation, in which the insulating sleeve has a second cross-sectional shape and is longitudinally slitted. Figs. 7A, 7B, and 7C show a cable assembly according to the first implementation. Figs. 8A, 8B, and 8C show two conductor assemblies according to the first implementation, in which the respective insulating sleeves of the conductor assemblies have a first cross-sectional shape and are integrally formed with each other. Figs. 9A, 9B, 9C, 9D, and 9E show two conductor assemblies according to the first implementation, in which the respective insulating sleeves of the conductor assemblies have a second cross-sectional shape and are integrally formed with each other. Figs. 10A, 10B, IOC, 10D, 10E, and 10F show two conductor assemblies according to the second implementation, in which the respective insulating sleeves of the conductor assemblies are integrally formed with each other. Figs. 11A and 11B each show a cable assembly according to the first implementation. Figs. 12A, 12B, 12C, 12D, 12E, and 12F show a cable assembly comprising two conductor assemblies according to the second implementation, in which the respective insulating sleeves of the conductor assemblies are integrally formed with each other. Fig. 13 shows a cable assembly comprising two conductor assemblies according to the second implementation, in which the respective insulating sleeves of the conductor assemblies are not integrally formed with each other. Fig. 14A shows a graph illustrating the performance of a cable assembly in which a plurality of twisted strands are surrounded by an insulating sleeve made of a dielectric material. Fig. 14B shows a graph illustrating the performance of a cable assembly in which a plurality of loose strands are surrounded by an insulating sleeve made of a dielectric material. Fig. 15A shows a graph illustrating the performance of a cable assembly in which a plurality of twisted strands are surrounded by an insulating sleeve made of a dielectric, damping material. Fig. 15B shows a graph illustrating the performance of a cable assembly in which a plurality of loose strands are surrounded by an insulating sleeve made of a dielectric, damping material.

[0034] Throughout the description and the drawings, like reference numerals refer to like parts. Detailed description

[0035] In overview, the present disclosure relates to a conductor assembly for use in a cable assembly. The conductor assembly comprises an electrical conductor formed of multiple strands, and an insulating sleeve surrounding the electrical conductor. The electrical conductor is electrically conductive, while the insulating sleeve is electrically insulating.

[0036] The following features of the conductor assembly allow transmission of signals or power via the conductor assembly to be enhanced: • using strands which are slack (i.e., not under tension) within the insulating sleeve, at least when the insulating sleeve is unwound, i.e., strands which are longer than the insulating sleeve; • using strands which are loosely bunched, i.e., avoiding contact between each of the strands and, optionally, mounting the strands in a respective bung at each end of the insulating sleeve; • using fine strands, i.e., strands with low cross-sectional area; • laying the strands in a cavity; • using strands which are not bonded to the insulating sleeve; and / or • forming the insulating sleeve from particular materials.

[0037] These features each allow transmission to be enhanced when used alone, and allow transmission to be further enhanced when used in combination. Accordingly, the presence of any one of the above features at least partially counteracts the absence of any others of the above features. For example, the strands need not be as long compared to the insulating sleeve (and therefore need not undulate as much) when they are disposed in an insulating sleeve having an inner portion formed from a damping material. As another example, the strands need not be as loosely bunched when they are disposed in an insulating sleeve having an inner portion formed from a damping material. As yet another example, keeping the strands loosely bunched reduces the need for fine strands to be used.

[0038] As a result, any of the features of the sections titled 'Conductor assembly', 'Slack strands' , 'Loosely bunched strands' , 'Termination', 'Fine strands' , 'Strands laid in a cavity', 'Bonding to the insulating sleeve', 'Insulating sleeve material', 'Slitting', 'Cable assembly', 'Further implementations', 'Fabrication', 'Performance', and 'Other examples of the disclosure' may be combined unless indicated otherwise. In particular, the features of the sections titled 'Conductor assembly' and 'Cable assembly' may be combined with any or all of the features of the sections titled 'Slack strands' , 'Loosely bunched strands' , 'Termination', 'Fine strands' , 'Strands laid in a cavity', 'Bonding to the insulating sleeve', 'Insulating sleeve material', 'Slitting', 'Further implementations' , 'Fabrication', 'Performance', and 'Other examples of the disclosure'. Principles of operation

[0039] At a high level, the present disclosure relates to the formation of a unique structure of conductor that is flexible, and formed in such a way as to mitigate the propensity for resonance in the conductor that is characteristic of the material from which it is formed.

[0040] The overall principle is a signal or power conducting cable where the mechanical construction is designed so that the modal response of each of the component parts avoids entrainment of vibrations and common resonance between the components.

[0041] In systems engineering terms, this could be described as a signal or power conducting cable where the compound modal response of the cable's components is damped and stable.

[0042] Signal-induced resonance in a pair of conductors is a result of electromagnetism. Indeed, when a varying electrical signal is applied to a pair of conductors, the resultant electromagnetic field between the conductors creates mechanical vibrations that are propagated into the mechanical structures around (and including) the conductors .

[0043] The energy from these vibrations causes the conductors to move. Because the conductors are carrying a signal and are thus charged, this movement acts on the conductors to regenerate latent charges in the conductors, which are a function of the mechanical construction of the cable. The inventor has arrived at the insight that the net result is that, via mechanical excitation in the transmission path, an alias of the original signal is lost to mechanical energy, and then returned as a latent electrical alias back into the conductor. By superimposition, the latency and form of the alias causes additive or destructive interference with the original signal. The result of this is that signal integrity is lost and distorted in a way that is characteristic of the construction of the cable.

[0044] By controlling the physical attributes of the transmission medium in a particular manner, the interference with the original signal can be significantly reduced.

[0045] This to-and-fro exchange of electrical and mechanical energy between the wires and body of the cable gets concentrated to become a resonant 'ring' where the cable component parts are closely coupled and have similar resonant frequencies.

[0046] The result is that the original signal is altered because some of its electrical energy is lost to mechanical vibration, which is then replaced by the returning vibrational energy from the cable body.

[0047] A cable can be prevented from interfering with the signal in this way by breaking this cycle by ensuring that the components that make up the cable have dissimilar resonances, and that they are decoupled from each other.

[0048] An electrical cable consists of conductor, dielectric and sheath elements. Each element has a characteristic electrical and mechanical modal response, depending on how it is formed. In the current art, these elements are in contact, bonded or otherwise coupled, and thus the individual modes coalesce to form a dominant compound modal response in the cable. As the conductors carry timevarying currents, mechanical vibrations are electromagnetically induced between them. In the current art, conductors are electrically or mechanically coupled to each other and / or to the body of the cable, this energises the modal responses in the cable, especially when the frequency of the currents is harmonious to the compound modal response of the cable assembly or the modal response of other components constituting the cable. Conversely, mechanical vibrations in a cable energise the modal responses of the cable, and so vibrate the charged conductors. This generates charges to be superimposed on the conductors. The amplitude of this induction will be dependent on the charge on the conductors at any given time and is therefore modulated by the signal to create an alias ghost signal. This manifests as interference that is characteristic of the overall modal response of the cable.

[0049] This disclosure proposes methods to alter the modal response and / or coupling of conductors, dielectric and sheathing, so as to disrupt entrainment between them and achieve a cable with minimal common modal response .

[0050] In the technology of the present disclosure, a series of components that are separately tuned to prevent resonance between them are used. This is mainly done by reducing conductor strand diameters and making sure they remain separated from each other, so that, like a fine guitar string, the individual strand resonance is higher and out of the resonance range of the rest of the cable. The strands are loosely bunched to dissipate longitudinal waves in the conductor and its constituent strands and so that the conductor sits loosely within the insulating sleeve ensuring that the conductor behaves more like a soft string than a taut wire.

[0051] The technology of the present disclosure gives significant and measurable improvement to noise floor and signal resolution of any system where signal integrity is required.

[0052] In particular, the arrangement disclosed reduces the reactions of the conductor and dielectric to effects caused by electromechanical disturbances, caused by the signal being carried by the conductor or by mechanical disturbances imposed on the signal conductors and emanating from outside the cable (e.g., vibrations that are external to the cable assembly but in the proximity, such as loudspeaker cabinet vibration or airborne sound waves).

[0053] The result is a significant improvement in the clarity of transmission of the signal that can be both measured and is discernible to the receiver. For example, sound appears much clearer and more natural. As another example, square waves and other waves with abrupt signal changes retain their original form more closely and exhibit less resonance ring.

[0054] In summary, definition of signal is being lost in cables due to : • the modal wave vibrations between conductors when electrically excited, and the coupling with the modal responses of the other cable parts; and / or • injection of vibration into the body of the cable and consequent superimposition of electrostatic, tribo- and Maxwell-ian generated charges onto the conductors.

[0055] These effects are emphasised by the issue that amplitude of the superimposed 'noise' currents will be dependent on the field strength between conductors, and therefore, as the signal varies, the noise will be manifest as an alias of the signal which, depending on relative frequency and phase, additively or destructively combines with the desired signal. Applications

[0056] A number of potential applications of the technology of the present disclosure are now described. These applications are described by way of example only, and are not to be taken as limiting the present disclosure.

[0057] The technology of the present disclosure may be applied to audio cables. The undesirable phenomena described above result in loss of signal definition around the vibration modes of the cable.

[0058] The technology of the present disclosure may be applied in signal and reference ground wires, and in mains ground wires in cables for systems where enhanced signal resolution is desired, e.g., in audio applications, sonar, ultrasound, sensitive signal transmission, high speed data, etc.

[0059] In digital data cables (e.g., Universal Serial Bus (USB) cables), the vibrations lead to modulation of waveforms which, in turn, causes drift of discriminator thresholds, leading to jitter in a signal and clocking drift in phase locking and re-clocking devices. The resulting increase in uncertainty of signal transition and timing, in turn, leads to increased errors and reduction of useable bandwidth and information capacity.

[0060] Similar electromechanical mechanisms can occur in video cables, RF cables, printed circuit boards, power cable ground paths, etc., and other systems.

[0061] In power cabling and power distribution, the effect is not associated directly to the energised power feed, but phenomena caused by electromagnetic interaction with ground cables. The effect becomes manifest in a system because ground cables are often associated or connected directly or inductively or capacitively to system signal reference points. Conductor assembly

[0062] A number of implementations of the conductor assembly and cable assembly of the present disclosure are illustrated in the figures .

[0063] The conductor assembly 100 comprises an electrical conductor 110 formed of multiple strands 110-1, 110-2, ..., 110-N and an insulating sleeve 120 surrounding the electrical conductor 110. The strands 110-1, 110-2, ..., 110-N may be mounted within a respective bung 140 at each end of the insulating sleeve 120.

[0064] Fig. 1 shows a key for the figures of the present disclosure. In particular, Fig. 1 shows an electrically conductive material of the first strand 110-1, an electrically conductive material of the second strand 110-2, an insulating sleeve material of the insulating sleeve 120, a sheath material of the sheath 130, and a bung material of the bung 140. Slack strands

[0065] When the strands 110-1, 110-2, ..., 110-N make contact with the insulating sleeve 120, they may begin to resonate. In order for the strands 110-1, 110-2, ..., 110-N to act independently of each other to avoid common modes from entrainment and to act independently of the insulating sleeve 120, the strands 110-1, 110-2, ..., 110-N may be slack within the insulating sleeve 120. By 'slack', it is meant that the strands 110-1, 110-2, ..., 110-N are not under tension.

[0066] Figs. 2A, 2B, 2C, and 2D show a conductor assembly 100 according to a first implementation in which the strands 110-1, 110-2, ..., 110-N are slack within a cavity of the insulating sleeve 120. In particular, Figs. 2A, 2B, and 2C respectively show an isometric view, a side view, and a side sectional view of the conductor assembly 100. Fig. 2D shows sectional views along planes A1-A2, BIBI, C1-C2, D1-D2, E1-E2, F1-F2, G1-G2, and H1-H2 as shown in Fig. 2C.

[0067] Slackness is achieved by making the strands 100 longer than the insulating sleeve 120; in other words, by giving the strands 110-1, 110-2, ..., 110-N 'excess length' . In some implementations, a respective length of each of the plurality of strands 110-1, 110-2, ..., 110-N within the insulating sleeve 120 thus exceeds a length of the insulating sleeve 120 by at least 0.5%.

[0068] By providing additional excess length, resonance may be further decreased. This may also promote each strand to follow a marginally different route through the insulating sleeve and thus reduce propensity of modal vibration entrainment between the strands 110-1, 110-2, ..., 110-N. In some implementations, the respective length of each of the plurality of strands 110-1, 110-2, ..., 110-N within the insulating sleeve 120 thus exceeds the length of the insulating sleeve 120 by at least 10%. This additional excess length may counteract the absence of a damping material in the insulating sleeve 120, as described below.

[0069] In some implementations, the respective length of each of the plurality of strands 110-1, 110-2, ..., 110-N within the insulating sleeve 120 exceeds the length of the insulating sleeve 120 by no more than 60%.

[0070] When the cable is wound (e.g., the cable is on a reel), the strands 110-1, 110-2, ..., 110-N may not be slack within the insulation sleeve 120, even if they would otherwise be slack. The strands 110-1, 110-2, ..., 110-N are therefore slack specifically when the insulation sleeve 120 is unwound (or 'not wound'). However, the strands 110-1, 110-2, ..., 110-N may be slack under both circumstances, i.e., when the insulation sleeve 120 is unwound as well as when the insulation sleeve 120 is wound.

[0071] The excess length of the strands 110-1, 110-2 is illustrated in Figs. 3A, 3B, and 3C. Fig. 3A shows a side sectional view of a conductor assembly 100 in which the strands 110-1, 110-2 are in tension within the insulating sleeve 120. The insulating sleeve 120 has a length LI, and the strands 110-1, 110-2 have a length L2, where L2 is greater than LI. Fig. 3B shows a side sectional view of the conductor assembly 100 in which the strands 110-1, 110-2 are now slack within the insulating sleeve 120. The strands 110-1, 110-2, which still have length L2, are now contained in the insulating sleeve 120 of length LI. The strands 110-1, 110-2 are thus axially compressed. Fig. 3C shows a side sectional view of a conductor assembly 100 in which the strands 110-1, 110-2 are slack within the insulating sleeve 120 and are mounted within a respective bung 140 at each end of the insulating sleeve 120.

[0072] When the strands 110-1, 110-2, ..., 110-N are slack, each of the plurality of strands 110-1, 110-2, ..., 110-N may be arranged in a serpentine (or 'sinuous', or 'zigzagging', or 'meandering', or 'winding') manner within the insulating sleeve 120. An example of the serpentine manner in which the strands 110-1, 110-2, ..., 110-N may be arranged is illustrated in Figs. 2C, 3B, and 3C. Loosely bunched strands

[0073] When strands 110-1, 110-2, ..., 110-N are bound together, and particularly when they are under tension, they behave like one monolithic mass with a consequently stronger resonance mode. In order to act independently of each other, and not respond as conjoined elements with an associated lumped, lower frequency, the strands 110-1, 110-2, ..., 110-N may be loosely bunched. In other words, in some implementations, contact between each of the strands 110-1, 110-2, ..., 110-N is avoided, and the strands 110-1, 110-2, ..., 110-N are not closely bound or twisted together. Keeping the strands loosely bunched ensures that the resonant behaviour of the strands is dictated by the (smaller) cross-sectional area of each individual strand, rather than the (greater) sum of the cross-sectional areas of the strands, and the resonant behaviour can thereby be more easily and more effectively dampened. In addition, if each strand follows a marginally different route through the insulating sleeve, the points of contact between each strand and any other strands and between each strand and the insulating sleeve becomes irregular, thus promoting each strand to individual damping and resonance modes throughout the assembly and so further avoiding entrainment and promoting the non-homogenous modal behaviour of string rather than that of taut wire.

[0074] Specifically, in some implementations, no more than 70% of a respective length, within the insulating sleeve 120, of each one of the plurality of strands 110-1, 110-2, ..., 110-N is in contact with any other strand(s) of the plurality of strands 110-1, 110-2, ..., 110-N. In other words, in some implementations, at least 30% of a respective length, within the insulating sleeve 120, of each one of the plurality of strands 110-1, 110-2, ..., 110-N is not in contact with any other strand(s) of the plurality of strands 110-1, 110-2, ..., 110-N. In yet other words, in some implementations, no strand has contact with any other strand for more than 70% of its length. Any of these properties may, in some implementations, be met only in portions of the insulating sleeve 120 having a non-trivial length. For example, in some implementations, in a (or preferably any) portion of the insulating sleeve 120 having a length of at least 30mm (preferably, at least 50mm, more preferably, at least 100mm), no more than 70% of a respective length, within the insulating sleeve 120, of each one of the plurality of strands 110-1, 110-2, 110-N is in contact with any other strand(s) of the plurality of strands 110-1, 110-2, ..., 110-N.

[0075] By further reducing contact, resonance may be further reduced. Thus, in some implementations, no more than 10% of a respective length, within the insulating sleeve 120, of each one of the plurality of strands 110-1, 110-2, ..., 110-N is in contact with any other strand(s) of the plurality of strands 110-1, 110-2, ..., 110-N. In other words, in some implementations, at least 90% of a respective length, within the insulating sleeve 120, of each one of the plurality of strands 110-1, 110-2, ..., 110-N is not in contact with any other strands(s) of the plurality of strands 110-1, 110-2, ..., 110-N. In yet other words, in some implementations, no strand has contact with any other strand for more than 10% of its length.

[0076] As one example, for an electrical conductor 110 formed of strands 110-1, 110-2, ..., 110-N, no more than 10% of the length of strand 110-1 is in contact with any other strand 110-2, ..., 110-N, no more than 10% of the length of strand 110-2 is in contact with any other strand 110-1, 110-3, ..., 110-N, and no more than 10% of the length of strand 110-N is in contact with any other strand 110-1, 110-2, ..., 110-N-l.

[0077] In the example of Fig. 3B, strand 110-1 is in contact with other strands in four places along its length L2. Strand 110-1 is in contact with other strands along a first portion Lci of its length L2, a second portion LC2 of its length L2, a third portion LC3 of its length L2, and a fourth portion LC4 of its length L2. The sum of Lci, LC2, LC3, and LC4 is no more than 7 0% of the length L2, within the insulating sleeve 120, of strand 110-1. Similarly, strand 110-2 is in contact with other strands in four places along its length L2. Strand 110-2 is in contact with other strands along a first portion Lci of its length L2, a second portion LC2 of its length L2, a third portion LC3 of its length L2, and a fourth portion LC4 of its length L2. The sum of Lci, LC2, LC3, and LC4 is no more than 7 0% of the length L2, within the insulating sleeve 120, of strand 110-2.

[0078] In some implementations, at least one of the plurality of strands 110-1, 110-2, ..., 110-N may be formed of a plurality of entwined sub-strands. In this case, in some implementations, no more than 70% (or no more than 10%) of a respective length, within the insulating sleeve 120, of each one of the plurality of strands 110-1, 110-2, ..., 110-N including their sub-strands is in contact with any other strand(s) of the plurality of strands 110-1, 110-2, ..., 110-N including any of their sub-strands. Again, any of these properties may, in some implementations, be met only in portions of the insulating sleeve 120 having a non-trivial length. For example, in some implementations, in a (or preferably any) portion of the insulating sleeve 120 having a length of at least 30mm (preferably, at least 50mm, more preferably, at least 100mm), no more than 70% (or no more than 10%) of a respective length, within the insulating sleeve 120, of each one of the plurality of strands 110-1, 110-2, ..., 110-N including their sub-strands is in contact with any other strand (s) of the plurality of strands 110-1, 110-2, ..., 110-N including any of their sub-strands.

[0079] In order to ensure that the strands 110-1, 110-2, ..., 110-N are loosely bunched along their full length, contact, within the insulating sleeve 120, between the one of the plurality of strands 110-1, 110-2, ..., 110-N and the any other strand(s) of the plurality of strands 110-1, 110-2, ..., 110-N may be longitudinally evenly distributed, or substantially evenly distributed. In other words, contact between each strand and any other strand(s) may be evenly, or substantially evenly, distributed along the length of the conductor 110.

[0080] More specifically, in some implementations, an average length of each of the plurality of strands 110-1, 110-2, ..., 110-N within the insulating sleeve 120 exceeds the length of the insulating sleeve 120 by a total cable excess length factor (which is greater than 1, e.g., 1.3). In a (or preferably any) portion of the insulating sleeve 120 having a length of at least 30mm, an average length of each of the plurality of strands 110-1, 110-2, ..., 110-N within the insulating sleeve 120 exceeds the length of the insulating sleeve 120 by a segment excess length factor (which is greater than 1, e.g., 1.2 or 1.4). The segment excess length factor (e.g., 1.2 or 1.4) in any of the portions of the insulating sleeve 120 varies between 50% and 200% or, preferably, 80% and 120% of the total cable excess length factor (e.g., between 80% and 120% of 1.3, which is between 1.04 and 1.56).

[0081] In other words, the percentage excess length in a (or preferably any) segment of the conductor assembly 100 at least 30mm in length is no more than 100% higher and no more than 50% lower or, preferably, no more than 20% higher and no more than 20% lower, than the mean percentage excess length over the entire conductor assembly 100. For example, if the mean percentage excess length over the entire conductor assembly 100 is 30%, the percentage excess length in a (or preferably any) segment of the conductor assembly 100 at least 30mm in length is preferably between 4% and 56%.

[0082] In yet other words, along a (or preferably any) length of insulating sleeve 120 where the length is a minimum length of 30mm, there is a length of conductor 110 material that is the same length as the length of insulating sleeve 120 plus an excess length of conductor 110 that exceeds said length of insulating sleeve 120 by a factor (which is greater than 1) of at least 0.5 times the ratio of the total length of conductor 110 divided by the total length of insulating sleeve 120, and by a maximum of 2 times the ratio of the total length of the conductor 110 divided by the total length of the insulating sleeve 120 or, preferably, by a factor of at least 0.8 times the ratio of the total length of conductor 110 divided by the total length of insulating sleeve 120, and by a maximum of 1.2 times the ratio of the total length of the conductor 110 divided by the total length of the insulating sleeve 120.

[0083] This can be expressed mathematically. In a length of insulating sleeve 120 of at least 30mm, the length of excess conductor 100 material (Le) in any length of insulating sleeve (Ld) is such that Le >((Ld x R) - Ld) x 0.5) and Le <((Ld x R) - Ld) x 2). That is to say 2 Ld x (R - 1 ) >Le >0.5 x Ld x (R -1), where R is a ratio, greater than 1, of the total length of conductor 110 to the total length of insulating sleeve 120. Preferably, 1.2 Ld x (R - 1 ) >Le >0.8 x Ld x (R -1). Termination

[0084] In order to ensure that, in handling and application, the strands maintain their loose arrangement, a respective bung may be placed at each end of the insulating sleeve 120, and the strands may be bonded / mounted within the bung. Such an arrangement is illustrated in Fig. 3C. The bung may be made of any soft bonding agent, such as a silicone compound - in particular, bathroom silicone sealant. Fine strands

[0085] As the resonant frequency is a function of diameter and Young's modulus, the electrical conductor(s) 110 may be made of fine strands in order to ensure that the strand resonant frequency is out of the range of being entrained by that of the rest of the cable.

[0086] By 'fine', it is meant that each of the plurality of strands 110-1, 110-2, ..., 110-N has a respective cross-sectional area of less than 0.1 square millimetres .

[0087] A strand can be made up of a tight twist of different substrands. In this case, by keeping the maximum cross-sectional area of the strand to less than 0.1 square millimetres, the impact of the tight twisting is counteracted. In other words, in some implementations, at least one of the plurality of strands 110-1, 110-2, ..., 110-N may be formed of a plurality of entwined substrands. In this case, the cross-sectional area of that strand, i.e., of the sum of the cross-sectional areas of each of the plurality of entwined sub-strands, may be less than 0.1 square millimetres .

[0088] Traditionally, fine strands are too frail to be deployed individually in a cable as they are likely to snap when under tension when the cable is manipulated or flexed in some fashion. Because of this many fine strands are traditionally twisted or cabled together to form a single flexible member that exhibits enough combined strength to withstand tension forces when a cable assembly is flexed or manipulated without snapping the strands. When, in the technology of the present disclosure, the individual strands are longer than the insulating sleeve that they are contained within, the loose nature of the strands within the containment of the insulating sleeve means that they are not subject to tension or stress when the cable assembly is manipulated and flexed in the way conductors are with alternative cable assemblies. This allows cables using the technology of the present disclosure to utilise conductors constituted of fine, unbound and slack strands without risk of damage to the individual strands when the cable is flexed or manipulated.

[0089] Larger strands may still be used with the technology of the present disclosure. Although larger strands could result in strong resonance within the individual strands, the use of damping material, as described below, can counteract this effect. The use of larger strands may be dictated by the application, e.g., for use as ground wires in power cables. Strands laid in a cavity

[0090] In order to dissociate the strands from vibration in the insulating sleeve and cable body, the strands may be laid in a cavity (or 'void' ), within the insulating sleeve 120 as shown, for example, in Figs. 2C, 2D, 3B, and 3C. The greater the size of the cavity, the more room there is for the strands to spread out and thus avoid contact with each other.

[0091] The cavity may be formed of a plurality of discontinuous sub-cavities. In other words, the cavity need not be formed of a single, continuous cavity, and may instead be formed of 'pockets' of cavity along the length of the insulating sleeve 120. Bonding to the insulating sleeve

[0092] In some implementations, the strands are bonded to the insulating sleeve 120. In other implementations, the strands are not bonded to the insulating sleeve 120. When the strands are not bonded to the insulating sleeve 120, resonance can be further reduced because the strands behave more autonomously with less modal entrainment resulting from the reduced coupling with the insulation sleeve 120. Insulating sleeve material

[0093] The insulating sleeve 120 may be made of a variety of materials. However, the inventor has arrived at the insight that, if at least an inner portion of the insulating sleeve 120 is made of a damping material, performance can be significantly improved. In order to work as a damping control system, the damping material is preferably highly compliant, i.e., has a low durometer hardness: high mechanical compliance increases efficient energy absorption from vibration of the (typically low-mass) strands.

[0094] The insulating sleeve 120, or at least an inner portion thereof, may nevertheless be made of a non-damping material. In some implementations in which at least an inner portion of the insulating sleeve is made of a non-damping material, the plurality of strands are not bonded to the insulating sleeve 120. This ensures that, although the insulating sleeve 120 is made of a non-damping material, resonance due to energy exchanges between elements, for example between conductor strands and insulation, is nevertheless reduced.

[0095] Figs. 4A, 4B, 4C, 4D, 4E, and 4F show a conductor assembly 100 according to a second implementation in which the insulating sleeve 120 is made of a damping material. In particular, Figs. 4A, 4B, 4C, 4D, and 4E respectively show an isometric view, a top view, a side view, a side sectional view, and a top sectional view of the conductor assembly 100. Fig. 4F shows sectional views along planes A1-A2, B1-B2, C1-C2, D1-D2, E1-E2, F1-F2, G1-G2, and H1-H2 as shown in Fig. 4E.

[0096] In tests, the desired level of damping begins to become apparent with damping materials of durometer hardness of 83 Shore (00) [35 Shore A] (e.g., soft urethane and rubber), and becomes significantly more efficient as this approaches 70 Shore (00) [30 Shore A] (e.g. polyisobutylene) (and even more so with durometer hardness in the region of 55 Shore (00) [10 Shore A] or less (e.g., soft gums and foamed or processed, gel like urethane).

[0097] The damping properties of the damping material can also be prescribed by its vibrational energy dissipation, or 'loss factor', of the material. This is referred to as 'tan delta' in dynamic mechanical analysis (DMA). A tan delta of 1 means a 50% loss of energy in tests, which is a high damping level. The higher the tan delta, the more dissipative the material.

[0098] DMA measurements can provide a comprehensive measurement of damping factor behaviour of a material at different frequencies and temperatures .

[0099] This damping preferably occurs in the range of frequencies and temperatures at which the assembly is to operate. Damping also preferably occurs in an element at the frequencies that its adjacent components have resonant modes.

[0100] In summary, the damping material preferably exhibits a high or ultra-high damping coefficient ('tan delta' ) and has high mechanical compliance, i.e., is soft (low durometer hardness).

[0101] Damping materials, such as monomer and polymer materials that exhibit a flexural loss factor (tan delta) of greater than 0.2 are common.

[0102] In tests, the desired damping begins to become apparent with damping materials of flexural loss factor greater than 0.4, (e.g. foamed, particulated or cellular soft, very low density polymers).

[0103] Damping becomes more significant with a damping material tan delta of 0.6 or greater, (e.g. polyisobutylene) and a substantially significant effect damping factor with a tan delta of 0.8 or greater (e.g. some processed urethanes, elastomers and isoprene material).

[0104] Accordingly, in some implementations, at least an inner portion of the insulating sleeve 120 is made of a damping material having one or both of (preferably, both of): a Shore 00 hardness of less than 83 or, more preferably, less than 70 or, yet more preferably, less than 55; or a loss factor (or 'tan delta', or 'tan 5', or 'flexural loss factor') greater than 0.2 or, more preferably, greater than 0.4 or, yet more preferably, greater than 0.6 or, yet more preferably, greater than 0.8. Alternatively, in some implementations, at least an inner portion of the insulating sleeve 120 is made of a (non-damping) material having one or both of: a Shore 00 hardness of at least 83, or at least 70, or at least 55; or a loss factor of no more than 0.2 or, more preferably, no more than 0.4 or, yet more preferably, no more than 0.6 or, yet more preferably, no more than 0.8.

[0105] The damping material may consist of solid, granular or gel materials, or a combination thereof. The damping material may consist of granules, powder, particles, fibres, strands, gel, solid materials, or a combination thereof. Granules, powder, particles, fibres, strands may, for example, include talc, chalk, or salt.

[0106] When the insulating sleeve 120 is made of a damping material, the plurality of strands may or may not be bonded to the insulating sleeve 120. When the plurality of strands is not bonded to the insulating sleeve 120, resonance is further reduced.

[0107] The loss factor effectively measures how efficiently a material recovers its initial form after being compressed. An increase in loss factor is either caused on a nano-scale by a lossy material molecular structure, or on a micro-scale by lack of structural integrity.

[0108] An example of 'nano-scale' loss is in polyisobutylene: its long molecules mesh poorly so that, when disturbed, its molecules dissipate energy because they scrape past each other rather than stretch and recover (as a more ordered structure would).

[0109] An example of 'micro-scale' loss is non-compacted dry sand. The mechanism is the same, but instead it is small particles that are frictionally dissipating energy as they scrape.

[0110] The Shore hardness is measured in accordance with the ASTM (American Society for Testing and Materials) D2240-15el (2021) testing standard ( 'Standard Test Method for Rubber Property-Durometer Hardness', available from https: / / doi.org / 10.1520%2FD2240-15E01) . The loss factor is measured in accordance with the ASTM E756-05 (2017) testing standard ('Standard Test Method for Measuring Vibration-Damping Properties of Materials' , available from https: / / doi.org / 10.1520 / E0756-05R17). The preferred Shore hardness and loss factor values set out herein are obtained at temperatures that may depend on the intended application. The preferred Shore hardness and loss factor values set out herein may be obtained at any (or, preferably, all) temperatures between 15 and 85 degrees Celsius (e.g., for internal equipment wiring for electric equipment). Preferably, the preferred Shore hardness values set out herein are obtained at any (or, preferably, all) temperatures between 15 and 28 degrees Celsius (e.g., for domestic audio cables). Yet more preferably, the preferred Shore hardness values set out herein are obtained at least at a temperature of 20 degrees Celsius. The preferred loss factor values set out herein may be obtained using dynamic mechanical analysis at frequencies that may depend on the operating frequencies of the intended application. The preferred loss factor values set out herein may be obtained at any (or, preferably, all) frequencies between 20 Hz and 1 kHz; preferably, the preferred loss factor values set out herein are obtained at least at a frequency of 800 Hz.

[0111] There is a large range of materials that meet, or can be engineered to meet, at least one of the Shore hardness and loss factor criteria set out above. A person of ordinary skill in the art will have no difficulty in identifying and obtaining such a material. Nevertheless, a selection of some suitable materials is set out below.

[0112] Suitable materials are characterised by being easily moulded, but with little elastic properties. There are several polymer materials that can give the desired result, but the Shore hardness and loss factor of a material varies significantly depending on formation process, its density and the formulation. For example, polyurethane can form a tough, solid plastic with high hardness and low loss factor, or it can be formulated and foamed to make a soft, high loss factor material for damping vibrations.

[0113] Historically, amorphous materials have not been considered or desired in cable making because they could not reasonably be formed into a reliable shape that would then hold its form and not be stretched. However, amorphous materials are highly non-resonant, being inherently energy dispersive. In addition, with an insulating sleeve 120 made of an amorphous material, cables can be made in layers, so cables with many copper strands (e.g., speaker or power) can have dispersive layers to avoid entrainment. Accordingly, in some implementations, the damping material may be an amorphous material.

[0114] Cross-linking gives a regularity that introduces resonance therefore, in some implementations, the damping material may be a non-cross-linked polymer.

[0115] In some implementations, the damping material may be an amorphous, non-cross-linked polymer.

[0116] In some implementations, the damping material may be an elastomer.

[0117] In some implementations, the damping material may be a polyolefin.

[0118] In some implementations, the damping material may be: polyisobutene, nitrile rubber, thermoplastic polyurethane, polychloroprene, silicone, Akton®, Hydrin® DP5245, Sorbothane®, polyisoprene, styrene-butadiene rubber, polybutadiene, acrylonitrile-butadiene rubber, isobutylene-isoprene rubber, ethylene propylene rubber, ethylene-propylene-diene monomer rubber, a polysulfide such as Thiokol®, polydimethylsiloxane, a fluoroelastomer, polyacrylate, chlorinated polyethylene, chlorosulfonated polyethylene, styrene-isoprene-styrene (SIS) block copolymer, styrene-butadiene-styrene (SBS) block copolymer, a polypropylene blend, or a combination thereof.

[0119] Examples of materials that can yield Shore 00 hardness of less than 83 include: Non hard-setting silica beads, and gels, Foamed granules, such as polyurethane, Foamed rubber and polymers such as polyurethane, Silica gels, Silicone rubber compounds, Loosely woven fabrics, Butyl plastics.

[0120] Examples of materials that can yield Shore 00 hardness of less than 70 include: Polyisobutylene, Plasticine, Non setting polymer putty, such as exercise putty, Hydrogels, Loose organic fibrous material, such as wool or wood fibre, Loose polymer fibrous materials, such as faux fur.

[0121] Examples of materials that can yield Shore 00 hardness of less than 55 include: Polyisobutylene, Very low durometer silicone rubbers, Proprietary polymer products, such as Sorbothane® (usually a polyurethane compound), Organic and / or irregular particles: Fine sand granules, silt and gel combinations, coffee grindings, Gelatine, Grease of consistency NLGI (National Lubricating Grease Institute) 0 to 2 (corresponding to a consistency range from 'mustard' to 'peanut butter'), Kids play 'Slime' type products.

[0122] Specifically, the damping material may be polyisobutene (or 'polyisobutylene'). Polyisobutene is flexible, has very high damping capabilities, is shock absorbing, can elongate up to 600%, has poor compression set, is stable in a wide temperature range (from -50 to +120 degrees Celsius), and is age resistant.

[0123] Polyisobutene has a medium-sized, irregular molecular chain, and is not as liquid as oil but is not locked in a solid, immutable form (not crystalline). Normally, for useful purposes it is transformed from a 'gum' to a fixed form by cross-linking the molecules by some process. However, cross-linking gives a regularity that introduces resonance therefore, in some implementations, the damping material may be polyisobutene in a non-cross-linked form.

[0124] The damping material may be one or more of: Monomers and polymers grouped by family: 1. Flexible polymer foams 2. Elastomers: Butyl Rubber (butadiene-based synthetic rubbers) Isoprene Silicone Elastomers Natural rubber Neoprene Polyurethane Ethylene-vinyl acetate (EVA) 3. Naturally occurring materials: Cork Chicle

[0125] The damping material may be a thermoplastic elastomer (e.g., thermoplastic polyurethane, which may be polyester-based or polyether-based), a vinyl-terminated high-consistency silicone rubber, polyethylene, urethane, or a combination thereof.

[0126] In some implementations, the damping material may be a combination of materials, the combination meeting one of the Shore hardness and loss factor criteria set out above. The combination may be a combination of one or more materials exhibiting nano-scale loss and one or more materials exhibiting micro-scale loss. For example, the damping material may be a mixture of sand (preferably, fine sand) and polyisobutylene granules.

[0127] Some of the materials listed above (e.g., polyurethane) may exist in multiple forms, only some of which meet the above Shore hardness and loss factor criteria. As these criteria are optional, forms not meeting the above Shore hardness and loss factor criteria may nevertheless be used in the technology of the present disclosure .

[0128] Figs. 4C, 4D, 4E, and 4F show an insulating sleeve 120 made entirely of a damping material. When the insulating sleeve 120 is made entirely of the damping material, the damping material is a dielectric, damping material.

[0129] However, resonance may be reduced even when only an inner portion of the insulating sleeve 120 is made of the damping material. In this case, the insulating sleeve 120 may comprise an inner layer made of the damping material and an outer layer made of a dielectric material. For example, the inner layer may be made of an amorphous damping material, and the outer layer may be made of a cross-linked polymer.

[0130] When at least an inner portion of the insulating sleeve 120 is made of a damping material, the strands may still be laid in a cavity (or 'void'), within the insulating sleeve 120. The cavity may again be formed of a plurality of discontinuous sub-cavities. In other words, the cavity need not be formed of a single, continuous cavity, and may instead be formed of 'pockets' of cavity along the length of the insulating sleeve 120.

[0131] The strands 110-1, 110-2, ..., 110-N need not be loosely bunched, or as loosely bunched, when they are disposed in an insulating sleeve 120 having an inner portion formed from a damping material, as described above. The damping material reduces the need for strands 110-1, 110-2, ..., 110-N to be kept apart. The strands 110-1, 110-2, ..., 110-N could be disposed, for example, in groups of several twisted strands, preferably loosely twisted. This can make manufacture easier: it can be easier to make an electrical conductor formed of 150 strands from, for example, 30 reels of 5 strands than from 150 reels of single strands. Slitting

[0132] In order to ease insertion of the electrical conductor(s) 110 into the insulating sleeve 120, the insulating sleeve 120 may be longitudinally slit. The sleeve may comprise a single slit along the length of, or a substantial portion (e.g., 90% or more) of the length of, the insulating sleeve 120.

[0133] Examples of such slitting are shown in Figs. 5A to 5F and 6A to 6E .

[0134] Figs. 5A, 5B, 5C, 5D, 5E, and 5F show conductor assemblies 100 according to the first implementation, in which the insulating sleeve 120 has a first cross-sectional shape and is longitudinally slitted. In particular, Figs. 5A and 5B respectively show an isometric view and a side sectional view of a conductor assembly 100 in which the insulating sleeve 120 is longitudinally slitted. Figs. 5C, 5D, 5E, and 5F show sectional views along plane A1-A2 as shown in Fig. 5B, illustrating four manners in which the insulating sleeve 120 may be longitudinally slit. In the examples of Figs. 5A, 5B, 5C, 5D, 5E, and 5F, the cross-sectional shape is a circular shape.

[0135] Figs. 6A, 6B, 6C, 6D, and 6E show conductor assemblies 100 according to the first implementation, in which the insulating sleeve 120 has a second cross-sectional shape and is longitudinally slitted. In particular, Figs. 6A and 6B respectively show an isometric view and a side sectional view of a conductor assembly 100 in which the insulating sleeve 120 is longitudinally slitted. Figs. 6C, 6D, and 6E show sectional views along plane A1-A2 as shown in Fig. 6B, illustrating three manners in which the insulating sleeve 120 may be longitudinally slit. In the examples of Figs. 6A, 6B, 6C, 6D, and 6E, the cross-sectional shape is a rectangular shape. Cable assembly

[0136] The conductor assembly 100 can be used to form a cable assembly 200. The cable assembly 200 comprises at least one of the conductor assemblies 100 described herein, and a sheath (or 'jacket') 130 surrounding the at least one of the conductor assemblies 100.

[0137] The sheath 130 provides solidity to the conductor assembly 100 and allows multiple conductor assemblies 100 to be kept together .

[0138] The sheath 130 may be a neoprene rubber jacket, or may be made of another soft, cross-linked polymer. The sheath 130 may be extruded around the at least one of the conductor assemblies 100.

[0139] The cable assembly 200 may further comprise a first electrical connector and a second electrical connector at respective ends of the cable assembly 200. The first and second electrical connectors may bind the sheath 130 to the at least one of the conductor assemblies 100, thus enabling the cable assembly 200 to be handled without upsetting the internal arrangement of the cable assembly 200 (i.e., pulling the strands out). At least until the first and second electrical connectors are placed on the ends of the cable assembly 200, the bungs at each end of the insulating sleeve(s) 120 (if present) may also provide such protection.

[0140] When there are multiple conductor assemblies 100, the cable assembly 200 comprises a plurality of insulating sleeves 120. However, the insulating sleeves 120 of each of the plurality of the conductor assemblies 100 may be integrally formed with each other.

[0141] As the conductor assemblies 100 can be manufactured and sold without a sheath 130, the conductor assemblies 100 are disclosed both separately, and in combination with, the sheath 130. Further implementations

[0142] Figs. 7A, 7B, and 7C show a cable assembly 200 according to the first implementation. In particular, Figs. 7A and 7B respectively show a top view and a side sectional view of the cable assembly 200. Fig. 7C shows a sectional view along plane A1-A2 as shown in Fig. 7B. The cable assembly 200 comprises a single conductor assembly 100 surrounded by a sheath 130. The conductor assembly 100 in turn comprises a single electrical conductor 110, formed of strands 110-1 and 110-2, surrounded by an insulating sleeve 120.

[0143] Figs. 8A, 8B, and 8C show two conductor assemblies 100 according to the first implementation, in which the respective insulating sleeves 120 of the conductor assemblies 100 have the first, circular cross-sectional shape and are integrally formed with each other. In particular, Figs. 8A and 8B respectively show an isometric view and a side sectional view of the conductor assemblies 100. Fig. 8C shows a sectional view along plane A1-A2 as shown in Fig. 8B. A first one of the conductor assemblies 100 comprises an electrical conductor 110a formed of a first strand 110-la and a second strand 110-2a. A second one of the conductor assemblies 100 comprises an electrical conductor 110b formed of a first strand 110-1b and a second strand 110-2b.

[0144] Figs. 9A, 9B, 9C, 9D, and 9E show a similar arrangement to 8A, 8B, and 8C. Figs. 9A, 9B, 9C, 9D, and 9E show two conductor assemblies 100 in which the respective insulating sleeves 120 of the conductor assemblies 100 have the second, rectangular cross-sectional shape and again are integrally formed with each other. In particular, Figs. 9A and 9B respectively show an isometric view and a side sectional view of the conductor assemblies 100. Fig. 9C shows a sectional view along plane A1-A2 as shown in Fig. 9B, in which the insulating sleeve 120 is not longitudinally slitted. Figs. 9D and 9E show sectional views with the section taken along plane A1-A2 as shown in Fig. 9B, illustrating two manners in which the insulating sleeve 120 may be longitudinally slit.

[0145] Figs. 10A, 10B, 10C, 10D, 10E, and 10F show two conductor assemblies 100 according to the second implementation, in which the respective insulating sleeves 120 of the conductor assemblies 100 are integrally formed with each other. In particular, Figs. 10A, 10B, 10C, 10D, and 10E respectively show an isometric view, a top view, a side view, a side sectional view, and a top sectional view of the conductor assemblies 110. Fig. 10F shows sectional views along planes A1-A2, B1-B2, C1-C2, D1-D2, E1-E2, F1-F2, G1-G2, and H1-H2 as shown in Fig. 10E.

[0146] Figs. 11A and 11B each show cross-sectional views of a cable assembly 200 according to the first implementation. In particular, Fig. 11A shows a cable assembly 200 comprising two conductor assemblies 100, in which the respective insulating sleeves 120 of the conductor assemblies 100 are integrally formed with each other. The conductor assemblies 100 are surrounded by the sheath 130.

[0147] Fig. 11B shows a cable assembly 200 comprising two conductor assemblies 100, in which the respective insulating sleeves 120a, 120b of the conductor assemblies 100 are not integrally formed with each other. The conductor assemblies 100 are surrounded by the sheath 130.

[0148] Figs. 12A, 12B, 12C, 12D, 12E, and 12F show a cable assembly 200 comprising two conductor assemblies 100 according to the second implementation, in which the respective insulating sleeves 120 of the conductor assemblies 100 are integrally formed with each other. In particular, Figs. 12A, 12B, 12C, 12D, and 12E respectively show an isometric view, a top view, a side view, a side sectional view, and a top sectional view of the cable assembly 200. Fig. 12F shows sectional views along planes A1-A2, B1-B2, C1-C2, D1-D2, E1-E2, Fl-Fl, G1-G2, and H1-H2 as shown in Fig. 12E.

[0149] Fig. 13 shows an isometric view of a cable assembly 200 comprising two conductor assemblies 100 according to the second implementation, in which the respective insulating sleeves 120a, 120b of the conductor assemblies are not integrally formed with each other. The conductor assemblies 100 are surrounded by the sheath 130.

[0150] Although the technology of the present disclosure has been illustrated primarily by way of electrical conductors 110 comprising two strands 110-1, 110-2, it will be understood that many more strands may be used - for example, tens or hundreds of strands may be used. Similarly, although the technology of the present disclosure has been illustrated primarily by way of cable assemblies 200 comprising one or two conductor assemblies 100, it will be understood that many more conductor assemblies 100 may be used.

[0151] Although the technology of the present disclosure has been illustrated primarily by way of electrical conductors 110 comprising strands 110-1, 110-2, ..., 110-N of equal length, these strands 110-1, 110-2, ..., 110-N may have different lengths.

[0152] Although the technology of the present disclosure has been illustrated primarily by way of cable assemblies 200 in which the sheath 130, conductor assemblies 100, and / or insulating sleeves 120 have a circular or rectangular cross-section, it will be understood that the cross-section may have any shape - for example, the crosssection may have an oval shape. Fabrication

[0153] In order to fabricate the conductor assembly 100, the insulating sleeve 120 may be elastically stretched, and the conductor 110 placed therein, so that when the insulating sleeve 120 is relaxed, the conductor 110 scrunches up loosely inside. More specifically, the insulating sleeve 120 may be elastically stretched, and the conductor 110 placed therein, so that the conductor assembly 100 has any of the features described herein, and in particular any of the features of the sections titled 'Slack strands' and 'Loosely bunched strands' .

[0154] Amorphous damping materials are straightforward to extrude to shape at low temperatures, and therefore may be extruded continually as blades from two parallel nozzles, so as to sandwich the strands as they, themselves, are pushed between the two blades. The strands may be pushed in at a slightly faster rate to cause the strands to be slack within the insulating sleeve 120. Performance

[0155] The performance of the conductor assemblies 100 and cable assemblies 200 according to the technology of the present disclosure is now presented.

[0156] A step wave is applied to a Im length of a number of different cables under test, and the resultant response wave is recorded. Each of the cables under test is made of the same strands 110-1, 110-2, ..., 110-N.

[0157] Improved performance is considered to be shown when the resonance resulting from the energising by the step wave is strongly and / or quickly damped.

[0158] Fig. 14A shows the response wave for a cable assembly 200 in which a plurality of twisted strands 110-1, 110-2, ..., 110-N are surrounded by an insulating sleeve 120 made of a dielectric material. Fig. 14B shows the response wave for a cable assembly 200 in which a plurality of loose strands 110-1, 110-2, ..., 110-N (i.e., not twisted or tensioned) are surrounded by an insulating sleeve 120 made of a dielectric material. Fig. 15A shows the response wave for a cable assembly 200 in which a plurality of twisted strands 110-1, 110-2, ..., 110-N are surrounded by an insulating sleeve 120 made of a dielectric, damping material. Fig. 15B shows the response wave for a cable assembly 200 in which a plurality of loose strands 110-1, 110-2, ..., 110-N are surrounded by an insulating sleeve 120 made of a dielectric, damping material.

[0159] Fig. 14A shows the most reactivity to the energising step wave. Here there is a larger vertical excursion and longer settling time than in Figs. 14B, 15A, and 15B.

[0160] Fig. 14B shows an almost halving of the overshoot (vertical excursion).

[0161] Fig. 15A shows a similar overshoot to Fig. 14A, but the resonance is damped more quickly.

[0162] Fig. 15B shows a reduced overshoot and reduced settling time compared to Fig. 14A. The comparative improvement between Fig. 14A and Fig. 15B is significant.

[0163] This clearly demonstrates improvement in transmission quality of a cable by the reduction of resonance impressed on a signal carried by the cable when the technology of the present disclosure is implemented.

[0164] Improvements in the following measures are also expected: • clarity of signal or signal integrity; • energy transfer to undesired frequencies; • measured impedance in desired range; • clarity of wave form modulation; • preservation of phase amplitude; • level of signal jitter; • level of clocking drift; • level of external vibration sources; • level of independent modal response; • level of entrainment; and • non-resonant behaviour. Other examples of the disclosure

[0165] An electrical signal transmission lead is formed with conductor and dielectric arrangement where the conductor element is formed with stands where each strand is laid in parallel to other strands without twisting strands or binding them and each strand remains un-tethered or un-bound to any other strand. Apart from casual contact between neighbouring strands each individual strand is able to move independently from other strands. Apart from casual contact between strands and dielectric elements each individual strand is able to move independently from the dielectric element. The path of the longitudinal axis of each strand is anfractuous or concertinaed or otherwise caused to stochastically and sinuously deviate from the mean axis of the dielectric when the dielectric is laid in a straight line to form a stochastically formed irregular net / web / mesh along their longitudinal axis. The total deviation from the mean axis of the dielectric when the dielectric is laid in a straight line amounts to a reduction in the axial length of each strand as laid in the conductor by a minimum of, e.g., 10 percent of the length of the said conductor strand when laid straight along its longitudinal axis. The distribution of the conductor strand that deviates from the mean axis of the dielectric when the dielectric is laid in a straight line is (approximately) evenly distributed along the length of the dielectric, e.g., to within 25 percent tolerance. Each individual strand diameter has a maximum diameter of 0.1mm. The void within the dielectric that contains the collection of strands has a minimum cross-sectional form that is equal to the outline of the cross sectional projection of the group of conductor strands when the axis of the strands are stochastically and sinuously deviated from the mean axis of the dielectric in said manner. The maximum cross-sectional area of the void is, e.g., 400 square mm.

[0166] An arrangement of a conductor of a single or multitude of fine strands in a cavity within a dielectric. The strand maximum cross-sectional area is 0.1mm. The strands are longer than the dielectric by a minimum of 5% and run within the dielectric length in an unbound arrangement with the excess strand material distributed along the dielectric length. The strands are loose / move independently of each other. On average, no two strands are in contact with each other for more than 10% of their length. The minimum cross-sectional area of dielectric cavity is such that it accommodates the spread of the strands.

[0167] A conductor and dielectric arrangement. The dielectric is a tube form with a cavity within. The conductor is made up of a single strand or plurality of strands. The strands are in a loose bunch formation and are not bound or tethered or bonded together in anyway except at the termination at either end. The individual stands are each of a maximum cross-sectional area of 0.1mm. The length of the conductor strands exceeds the length of the dielectric by at least 5% and not more than 60%. The strands are fully contained within the cavity of the dielectric with the excess lengths of the conductor strands being accommodated by condensing / compacting them along their length by means of lateral spreading of the strands within the dielectric cavity with the spread distributed along the length of the dielectric cavity. The lateral spread of the strands within the dielectric cavity may be, but not necessarily, in the form of corkscrew within the cavity, or ruffled or zigzag along the length of the cavity. Along the length of the conductor no two strands are in contact with each other for more than 10% of their length. The void within the dielectric is of a minimum cross-sectional area to accommodate the spread of the conductor strands. The strands are not bound or tethered or bonded to the dielectric in any way except at the termination at either end.

[0168] A conductor and dielectric arrangement. The conductor is made up of a plurality of strands. The individual stands are each of a maximum cross-sectional area of 0.1mm. The strands are not bound or tethered or bonded together in anyway except where in contact due to the spread of the strands within the conductor or where the conductors are terminated at either end of the conductor and dielectric arrangement. Along the length of the conductor no two strands be in contact with each other for more than 10% of their length. The length of the conductor strands LC exceeds the length of the dielectric LD by at least 0.5% and not more that 60%. The said strands of length LS are fully contained within the length of the dielectric LD. With the excess lengths of the conductor strands (LS-LD) being accommodated by condensing / compacting them along their length by means of lateral spreading of the strands within the dielectric with the spread distributed along the length of the dielectric. The dimension within the dielectric is of a minimum cross-sectional area to accommodate the spread of the conductor strands. The dielectric is formed from viscoelastic amorphous insulating material with a Shore hardness on the Shore 00 Scale of between 1 and 50 that remains solid and pliable (mouldable) between the temperatures of -40C and +120C. The viscoelastic dielectric material is viscous to the degree that where in contact with the strand material the mechanical system response of the combination of the conductor strands and dielectric material exhibit a damping ratio greater than unity in terms of damping mechanical vibration within the conductor and dielectric (over-damped system therefore no oscillations). Mass of the conductor strands and the viscoelastic combine to have a damping ratio on oscillations and vibration set up in the conductor strand that is greater than a damping ratio of unity.

[0169] A dielectric and conductor assembly where the conductors are made of bare wire (non-insulated) strands. Damping material / cavity option: strands are contained with a viscoelastic material or within a cavity made of a viscoelastic material that has a Shore hardness on the Shore 00 scale of between 1 and 50, between the temperatures from -30 and +120 degrees C where the viscoelastic material is a dielectric material or that the viscoelastic material is contained within a dielectric material. Excess strand: assembled strand lengths exceed dielectric length (by 0.5%) and excess length is distributed along the length of the assembly. Contact area: no single strand has contact with any other strand for more than 70% of its length and any such contact is distributed along the length of the strands, but where there is contact electrical conduction can occur between strands. Maximum strand CSA: the cross-sectional area any strand <0.1 square mm.

[0170] A conductor and dielectric arrangement where the conductor is formed from a plurality of strands, where at least one of the said strands is made of a conductive material. Where all the said strands maybe of similar cross-sectional form to each other or maybe of dissimilar cross-sectional form to the other stranded elements comprising the said conductor. Where all the said strands maybe of similar cross-sectional area to each other or maybe of dissimilar cross-sectional area to the other stranded elements comprising the said conductor. Where all the said strands maybe of similar material to each other or maybe of dissimilar material to the other stranded elements comprising the said conductor and some may also be non-conductive}. The strands to each have a maximum cross-sectional area (CSA) of 0.126 square mm. Except for at the termination of the cable assembly 200 no strands are bound or twisted or in any other way bonded to any other strand so that each strand is free to independently resonate with a modal response that is dominated by the individual strand frequency response function compared to the frequency response of the lumped conductor mass. Said strands are reduced in axial length by ruffling or concertinaing them continually along their length such that the axial length of the conductor is reduced by between 3% and 20%. Said strands are contained in a void within a solid form dielectric where the minimum cross-sectional area of said void is defined by the outline of the projected elevation of the excursion of the conductor from its longitudinal axis due to the ruffling or concertinaing of the conductor. Where the Young's Constant of the dielectric material is <4 and preferably <0.04. Where said void in the dielectric may fully enclose the conductor around its circumference or said void may be formed with a fissure along its length. Where the ruffled dielectric is not bonded to the dielectric material. Where the dominant resonant modal responses of said individual strands is at a frequency that differs adequately from the dominant resonant modal responses of said dielectric so as to prevent a modal response entrainment of the conductor strands and dielectric.

[0171] An enclosure of amorphous dielectric around a ziz-zag stranded conductor - with or without a void. Interpretation

[0172] Section titles are provided above to ease understanding of the disclosure, and are not to be construed as limiting the scope of the disclosure.

[0173] Those skilled in the art will recognise that the scope of the invention is not limited by the examples described herein, but is instead defined by the appended claims.

Claims

1. A conductor assembly comprising:an electrical conductor formed of a plurality of strands; andan insulating sleeve surrounding the electrical conductor,wherein each of the plurality of strands has a respective cross-sectional area of less than 0.1 square millimetres,wherein the plurality of strands are slack within the insulating sleeve when the insulating sleeve is unwound, andwherein no more than 70% of a respective length, within the insulating sleeve, of each one of the plurality of strands is in contact with any others of the plurality of strands.06 11 242. The conductor assembly of claim 1, wherein at least an inner portion of the insulating sleeve is made of a material having one or both of a Shore 00 hardness of at least 83 and a loss factor of no more than 0.2, and wherein the plurality of strands are not bonded to the insulating sleeve.

3. The conductor assembly of claim 1, wherein at least an inner portion of the insulating sleeve is made of a damping material having a Shore 00 hardness of less than 83 and a loss factor greaterthan 0.2.

4. The conductor assembly of any preceding claim, wherein no more than 10% of a respective length, within the insulating sleeve, of each one of the plurality of strands is in contact with any others of the plurality of strands.

5. The conductor assembly of any preceding claim, whereincontactwithin the insulating sleeve, between the one of theplurality of strands and the any others of the plurality of strandsis longitudinally substantially evenly distributed.

6. The conductor assembly of any preceding claim when dependenton claim 3, wherein the damping material is an elastomer.

7. The conductor assembly of any preceding claim when dependenton claim 3, wherein the damping material is a polyolefin.06 11 248. The conductor assembly of any preceding claim when dependent on claim 3, wherein the damping material is: polyisobutene, nitrile rubber, thermoplastic polyurethane, polychloroprene, silicone, Akton®, Hydrin® DP5245, Sorbothane®, polyisoprene, styrene-butadiene rubber, polybutadiene, acrylonitrile-butadiene rubber, isobutyleneisoprene rubber, ethylene propylene rubber, ethylene-propylene-diene monomer rubber, a polysulfide such as Thiokol®, polydimethylsiloxane, a fluoroelastomer, polyacrylate, chlorinated polyethylene, chlorosulfonated polyethylene, styrene-isoprene-styrene (SIS) block copolymer, styrene-butadiene-styrene (SBS) block copolymer, a polypropylene blend, or a combination thereof.

9. The conductor assembly of claim 8, wherein the dampingmaterial is polyisobutene.

10. The assembly of any preceding claim when dependent on claim 3,wherein the plurality of strands are bonded to the damping material.

11. The conductor assembly of any of claims 1 to 10 when dependent on claim 3, wherein the insulating sleeve comprises an inner layer made of the damping material and an outer layer made of a dielectric material.

12. The conductor assembly of any of claims 1 to 10 when dependent on claim 3, wherein the damping material is a dielectric, damping material, and wherein the insulating sleeve is made of the dielectric, damping material.

13. The conductor assembly of any preceding claim, wherein a respective length of each of the plurality of strands within the insulating sleeve exceeds a length of the insulating sleeve by at least 0.5%, optionally at least 10%.06 11 2414. The conductor assembly of any preceding claim, wherein a respective length of each of the plurality of strands within the insulating sleeve exceeds a length of the insulating sleeve by no more than 60%.

15. The conductor assembly of any preceding claim, wherein each of the plurality of strands is arranged within the insulating sleeve in a serpentine manner.

16. The conductor assembly of any preceding claim, wherein at least one of the plurality of strands is formed of a plurality of entwined sub-strands.

17. The conductor assembly of any preceding claim, wherein the insulating sleeve is longitudinally slitted.

18. A cable assembly comprising:at least one of the conductor assemblies of any preceding claim; anda sheath surrounding the at least one of the conductorassemblies .

19. The cable assembly of claim 18, wherein the cable assemblyfurther comprises a first electrical connector and a secondelectrical connector at respective ends of the cable assembly.

20. The cable assembly of any of claims 18 to 19, wherein the at least one of the conductor assemblies comprises a plurality of the conductor assemblies, and wherein the insulating sleeves of each of the plurality of the conductor assemblies are integrally formed with each other.06 11 24

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