Abstract: A process for obtaining a twisted pair electrical signal cable having conductors of equal physical length and equal signal transmitting properties by passing a parallel pair of adhered insulated conductors of equal length through a closely-fitting die and twisting the conductors into a twisted pair cable. The process applies to thermopolymer insulated and ePTFE insulated conductors.

Abstract: Ribbon cables have lower capacitance, higher impedance, and faster propagation velocities with microporous fibril thermoplastic dielectric insulation, because they have great amounts of air adjacent to the conductors and the improved electrical performance is due in part to the improved crush resistance. Crystallizable thermoplastic polymers having good fibril structure and crush resistance include polyolefins such as polypropylene and polymethylpentene. A layer of metal adhered to the dielectric insulation provides improved transmission line properties.

Abstract: An electrical ribbon cable of parallel, coplanar conductive wires having an insulating layer of sintered porous PTFE tape around each of the wires, and a second insulating layer of porous sintered PTFE film around the wires. A conductive layer is then applied and then an outer insulating layer. The cable may be simply and quickly mass-terminated by means of standard tools and connectors. It is constructed such that the velocity of propagation of a signal along any wire is greater than 85% of the velocity of propagation of signals along similar wires suspended in air, and such that the time delay of signal propagation from one end of any wire to the other end is less than 1.17 nanoseconds per foot of length of the cable.

Abstract: A coaxial cable of the type used for a drop cable for cable television includes flat reinforcing wires forming a reinforcing covering for a foil shield. The coaxial cable includes an elongate center conductor, a surrounding dielectric material, and an outer conductor including the foil shield and the plurality of flat reinforcing wires forming the reinforcing covering for the shield. The flat reinforcing wires may be braided or may be wrapped to form a served covering. The flat wires are preferably sized to have a greater strength than conventional round wires. Therefore, a method for manufacturing the cable may advantageously include the steps of applying the flat wires and extruding an outer protective jacket continuously in tandem to thereby increase manufacturing efficiency.

Abstract: The invention discloses a composite material 1 comprising essentially a mixture of hydroexpandable powder and thermobonding powder, sandwiched between two flat solid supports, one at least of which is at least partially hydrosoluble.This material can be used in agriculture, medicine, surgery, in the hygiene field and in the cable, particularly electric cable, industry. In this application, when water penetrates into the cable, the at least partially hydrosoluble support or supports release the hydroexpandable powder which rapidly forms a pad preventing propagation of the water through the cable.

Abstract: A porous insulating resin tape is fed to an inner or outer surface of one of insulating resin tapes with which a plurality of electrical conductors of a flat cable are coated. Printing is performed on at least one surface of surface of the porous insulating resin tape, soaks into the pores of the porous insulating resin tape. The pores are sealed up when the tape is pressed by a heating/pressing rollers and then baked, and the ink is shut off from outside the pores. The printing can be clearly performed without being discolored.

Abstract: An insulated conductor having improved arc propagation resistant properties. The insulation consists of a first layer of a composite tape of polyimide between two layers of polytetrafluoroethylene. The second overlaying tape layer is unsintered polytetrafluoroethylene. Further disclosed is a process for manufacturing a sintered wire product having a tin plated electrical conductor.

Abstract: A structure for an electrical cable which may be used as a high-frequency signal transmission line and which includes a jacket which is highly permeable by fluids to reduce the time required for stabilization of impedance and transmission speed of the cable upon placement into an environment characterized by a fluid dielectric having a different dielectric constant. The permeable jacket also facilitates electrical connection to a shield conductor of the transmission line, exposed through apertures in the jacket, by use of electrically conductive potting materials, and without the need to remove any portions of the jacket surrounding the shield conductor to which electrical connection is to be made.

Abstract: An improved insulated thermocouple having no asbestos insulation material. The improved thermocouple and a method for making it are described whereby individual conductors are wrapped with high temperature fiberglass insulation and are then coated with a fiberglass binder that may be a modified silicone liquid. The individual conductors are then assembled in a parallel configuration and an outer jacket of high temperature fiberglass is applied by a braiding process. The entire assembly having the exposed outer jacket is coated with a fiberglass binder that may be a polyurethane liquid, and then cured.

Abstract: A magnetic wave shield tape comprises a strip-shaped conductive member and a strip-shaped insulative member, the strip-shaped magnetic member being fixed to and overlapping the strip-shaped insulative member in the width direction.

Abstract: Forming a metal shield on a cable core in which a frusto-conical forming surface for the shield has a plurality of former sections disposed side-by-side from a downstream end of the former. The sections are removable, in order, from the downstream end to increase the downstream end diameter of the forming surface and may be replaced, in order, so as to decrease the diameter at the downstream end for the purpose of applying shields to cable cores of different diameters.

Abstract: An electric cable is disclosed that has improved burn resistance characteristics. The improved electric cable consists of an insulation portion that has a glass fiber yarn wrapped around the conductor. The glass fiber yarn is impregnated at an outer periphery by a first silicone mixture. A second silicone mixture is coated about the outer periphery of the glass fiber yarn. In an alternative embodiment, a silicone tape replaces the Fiberglas.TM. yarn. The improved insulation for electric cable is envisioned for use with both single strand and multi-strand wires.

Abstract: A paper-polymeric material, laminated tape, an electric cable insulated with such tape and a method of making the tape. The tape includes a film of polymeric material to at least one surface of which a paper tape comprising cellulose fibers is bonded by contacting the paper tape at room temperature with the film heated to a temperature above its melting temperature. Prior to contacting the paper tape with the heated film, fibrils are caused to project from at least one surface of the paper tape by subjecting it to a high voltage, electrostatic field. In the laminated tape, the fibrils are embedded in the material of the film to provide an improved bond between the film and the paper tape.

Abstract: Forming metal shield for cable core in which a metal tape is moved along a passline over a concave forming surface which tapers in a downstream direction. A convex rotating roller lying parallel to an adjacent region of the forming surface urges the tape against the concave surface to form the tape into a laterally curved shape. The tape then moves along the concave surface and through an overlapping die to complete the shape of the shield with the tape wrapped around the core with overlapped edges.

Abstract: A method of manufacturing a sensing element, comprising bringing a first body in the form of an oil-free cross-linked matrix of flexible elastomeric material, the matrix containing electrically conductive particles, into contact with a second body of flexible elastomeric material that is electrically insulating and that contains an oil compatible with the elastomeric material of the first body, and allowing oil to migrate from the second to the first body so as to cause swelling of the first body, the migration continuing until a state of oil phase equalisation between the two bodies is reached.

Abstract: A cable structure in round or flat form is characterized by a corrugated septum disposed intermediate an inner and an outer sheath. The septum contacts the sheaths to define tubular envelopes extending axially along the length of the cable. Each of the envelopes is able to receive a predetermined number of conductors. The sheaths and the septum are electrically connectable to a ground potential so as to totally electromagnetically isolate the conductors entirely along their axial lengths.

Abstract: An improved process and apparatus for making electric cable is disclosed that will result in electric cable with improved burn resistant characteristics. The improved process and apparatus consists of a first yarn wrapping portion, an impregnating section, a drying section, a coating section, a second drying section, and a coiling section for returning the wire to a reel. This process wraps a glass fiber yarn about an electric wire and then impregnates this yarn with a silicone mixture. The impregnated yarn is then dried and sent to a second coating chamber where an additional silicone mixture is coated about the outer periphery of the yarn. The wire goes into a second drying section and then goes on to the coiling section. In a second embodiment of this invention silicone tape is used to wrap around the electric wire than than the glass fiber yarn.

Abstract: In a process and a material for producing an electrically insulating sheathing around a junction between electrically conductive elements, the material comprises first and second layers which have different melting points and which are disposed around the junction in such a way that the layer having the lower melting point constitutes an inner layer around the junction while the layer having the higher melting point is disposed on the outside of the inner layer. The material is pressed around the junction by means of ultrasound welding, with the inner layer softening at least to such an extent that, under the pressure applied thereto by the outer layer, the inner layer fills any spaces between the junction and the outer layer, and the outer layer forming a sealing enclosure around the inner layer and the junction.

Abstract: Improved electrical insulating tapes are disclosed having a poly(ethylene terephthalate) film component. The film has one amorphous surface and an opposite crystalline surface. In a preferred embodiment, a composite insulating material is provided having the film component with a fiber glass yarn strand layer adhered thereto. The fiber glass yarn strands are substantially continuous and uninterrupted, and are substantially parallel to the axis of elongation of the tape, and to each other.

Abstract: An electrical component, such as a joint between bus bars, is insulated by wrapping therearound a sheet of gel-like material, and manually causing it to conform to the joint. The material is curable by ultra-violet radiation, and this is directed on to the wrapped sheet to cause it to harden. A recoverable tube may be mounted over the sheet, before or after curing, to provide additional protection.

Abstract: The invention provides a laminated wrap for repairing an electrical cable, the wrap being adapted to be stretched around the cable with the longitudinal sides of the wrap overlapping one another. The outer layer of the wrap is of a wear and fire resistant flexible material such as rubber while the inner layer is an adhesive layer preferably of uncured rubber which is adapted to vulcanize in contact with the surface of the cable. The outer layer includes an overlap zone which is preferably also of uncured rubber which is adapted to vulcanize in contact with the overlapping portion of the inner layer.

Abstract: Magnet wire substrates (1) are described having a layer of polyester tape (2) wrapped thereon, including a layer of spirally wrapped and bonded polyester insulation tape (3) as the outermost layer. The two tape layers are made up of amorphous (4) and crystalline (5) segments unbonded to the wire and bonded to each other to provide the requisite electrical properties and improved physical properties including increased flexibility and ease of strippability. A single multilayer polyester insulation tape can also be used with similar properties and reduced thickness.

Abstract: The invention relates to a hydroexpansible composite material, the method of preparing same and a composition for implementing this method, as well as to the uses thereof. The composite material includes a solid flat support having, on at least one of its faces, a coating with a high proportion of a hydroexpansible polymer powder fixed to the support by means of a hydrosoluble binder, the coating being essentially formed of:95 to 55% by weight of hydroexpansible polymer powder;5 to 23% by weight of hydrosoluble binder; and0 to 22% by weight of surfactant.This hydroexpansible material may advantageously be used in medicine, surgery agriculture and especially as sealing agent in cables, particularly electric cables.FIG. 2 shows how, in a cable, this material (11, 13) forms a sealing ring (13) about the point of infiltration of the water, thus preventing its longitudinal propagation.

Abstract: An apparatus and method is disclosed for wrapping a bundle of spliced wires to create a waterproof insulating cover for the splice, in which a segment of autogenous tape is fed over a cradle fixture prior to positioning the wire bundle thereover. Oppositely positioned hinged portions of wrapping members are each sequentially advanced to successively engage and fold each end of the tape segment over the wire bundle, each member cammed as it is advanced plunging down to press the tape end over the wire bundle. A pressure platen is advanced down onto the wrapped bundle to band the lapped tape portions together, with a relief cavity preventing undue thinning of the tape in the region of the uninsulated wire splice.

Abstract: Shield tape (10) surrounds cable (20) in a sleeve-like fashion as it is fit through forming die (22) into cabling machine (28). Shield tape (10) is a metal foil mounted on a plastic substrate. Microencapsulated lubricant in a binder is incorporated on the outer surface of the metal foil portion of the tape (10).

Abstract: Process for reducing the water vapour diffusion in a plastics composite insulator consisting of several layers by incorporation of at least one mica-containing layer as diffusion barrier in the form of a surface or intermediate layer on at least one plastics body, constituting the composite insulator.

Abstract: A cable structure in round or flat form is characterized by a corrugated septum disposed intermediate an inner and an outer sheath. The septum contacts the sheaths to define tubular envelopes extending axially along the length of the cable. Each of the envelopes is able to receive a predetermined number of conductors. The sheaths and the septum are electrically connectable to a ground potential so as to totally electromagnetically isolate the conductors entirely along their axial lengths.

Abstract: A wrap-around cable sleeve liner is formed from a blank consisting of a smooth covering sheet and a corrugated sheet, which are secured together and have a line of indentations extending at an angle to the corrugations of the corrugated sheet adjacent each end of the sheet to form a bend line for the adaptation portions. The cable sleeve liner blank is preferably cut from a large area panel and has the indentations formed after cutting the blank so that blanks for different sizes can be formed as needed.

Abstract: A high voltage, gas filled, pipe type electrical cable and method of manufacture thereof. The cable comprises a plurality of insulated conductors, each conductor having a central gas passageway and being gas permeable. The conductor is wrapped with tapes impregnated with an insulating oil, and the wrapped tapes are encircled by gas permeable layers and skid wires. Three of such insulated conductors are encircled by a gas impermeable pipe, and the pipe and the conductor passageways are filled with an insulating gas under pressure above atmospheric pressure so that both the interior and exterior surfaces of the wrapped tapes are subjected to such gas. Preferably, the gas is a mixture of sulfur hexafluoride and nitrogen at a pressure of at least 200 psig. The tapes are impregnated with the oil and drained before they are wrapped around the conductor so as to provide gaps between the tapes which are substantially filled with the gas.

Abstract: Improved method and apparatus for manufacturing transposed ribbon cable, an improved ribbon cable in which a plurality of insulated wires are juxtaposed in fixed relationship to each other, and an improved transposed ribbon cable in which each conductor of the cable of the invention is in the form of a continuous helix. The transposed ribbon cable is manufactured by the method and apparatus of the invention by folding a ribbon cable angularly with respect to the longitudinal axis repeatedly while advancing the ribbon cable incrementally.

Abstract: A direct current electric cable with a conductor, a semi-conductive screen around and contacting the conductor, a plurality of layers of insulation formed by tapes of insulating material around the semi-conductive screen, a further semi-conductive screen around the layers of insulation and a metal sheath around the further semi-conductive screen, the layers of insulation being impregnated with a non-migrating, insulation composition having a dropping point temperature at least 5.degree. C. above the maximum operating temperature of the cable and having an electronegative gas dissolved therein, the gas having a coefficient of diffusion in the composition in the range from 3.times.10.sup.-5 to 3.times.10.sup.-6 cm.sup.2 /sec at temperatures below the dropping point temperature of the composition.

Abstract: A highly flexible, shielded electrical cable having exceptional pliability and limpness is provided for connection to devices such as hand-held medical instruments to minimize the resistance to movement of such devices imposed by such cable. The normal stiffness of shielded cables caused by a braided wire shield is minimized by eliminating the frictional resistance to relative movement between the shield and the dielectric covering of the conductor assembly inside the shield. This is accomplished by loosely braiding the shield around the dielectric covering so as to impose no transversely inward force on the dielectric covering. Preferably, a clearance is formed between the shield and the dielectric covering, and the density of the braided shield is maximized to render it self-supporting. The outer dielectric jacket of the cable likewise loosely encircles the braided shield to eliminate frictional resistance to relative movement between the shield and jacket.

Abstract: Magnet wire substrates (1) are described having a layer of glass fiber (2) wrapped thereon, which has a layer of spirally wrapped and bonded polyester insulation tape (3) as the outermost layer. The resulting insulated magnet wire in addition to having the requisite electrical properties has improved physical properties including increased flexibility and ease of strippability.

Abstract: A leaky coaxial cable is designed to produce a defined coupling between its interior and exterior. A bonded and insulated outer conductor of relatively large width relative to the cable diameter, is spirally wound at a low pitch angle to provide at high frequencies a coupling level having minimal effect on the coaxial properties of the cable.

Abstract: A kit comprising materials for sealing leaks in low-pressure gas lines. The kit contains, (a) optionally, a container of corrosion-resistant primer composition; and (b) a special laminated tape comprising a ply of rubber such as neoprene and a ply of pressure-sensitive conformable polyer-based adhesive material based on, e.g., ethylene-propylene rubber, and (c) a seal restraining fabric impregnated with a curable resin such as moisture-curable polyurethane which is characterized by good shelf life and a controlled curing speed when subjected to moisture. The tape of the invention also relates to the novel protective patch structures which are formed by use of the kit material.

Abstract: A semi-foamed polyethylene tape for use in the molding of foamed jacket pethylene cables. After tumble mixing low density foaming polyethylene, ethylene vinyl acetate co-polymer and polyethylene color concentrate, the tape is extruded on a thermoplastic extruder having a maddox mixing screw that effectively mixes polyethylene compounds and a slot die with a suitable opening dimension. The tape is then quenched. By controlling manufacturing variables the tape is foamed to 40% to 50% of its maximum. The tape is then foamed to 100% maximum during the manufacturing of a cable assembly.

Abstract: A method of producing a shielding for a flexible electric line employs at least one conductor having insulation upon which is wound at least one metal tape, the tape being separated into individual elements by cutting immediately before contacting the insulation.

Abstract: A method of insulating a field coil of an electric traction motor, comprising the steps of encapsulating the coil in flexible ground insulation, temporarily mounting the insulated coil on a field pole piece, wrapping heat shrinkale material around the perimeter of the insulated coil, said material being so composed, oriented, and applied as to shrink irreversibly, when subsequently heated, in a direction tending to constrict the whole outside perimeter of the insulated coil, attaching the base of the pole piece to a concave surface of the magnet frame of the motor in a manner that compactly clamps the coil between the frame and an overhanging distal end of the pole piece, heating the perimeter wrap so that it shrinks appreciably and tightly binds the underlying ground insulation, thereby counteracting any tendency of the ground insulation to become slack on the outside of the coil when the coil was clamped in place, and filling any remaining voids inside the ground insulation with varnish or resin in a conven

Abstract: This invention provides a method of increasing the cut-through resistance of a PTFE insulated conductor. Unsintered PTFE is expanded and compressed and then applied to a conductor. The insulated conductor is then heated to a temperature above 345.degree. C. The compressed, expanded PTFE has one crystalline melt point above 375.degree. C.

Abstract: An electric cable (1) for transporting very high current at low voltage, in particular a welding cable for use in robot welders, comprises at least one multi-strand conductor (2) and an outer sheath (4), cooling water circulates inside the cable, and the water gains access to the conductor strands to be cooled by virtue of the conductor being covered by a perforated envelope (3).

Abstract: Curable compositions which are useful for encapsulating electrical connections and for joining metals to metals, and which comprise a mixture of high and low molecular weight fluorocarbon elastomers. Preferred compositions comprise a mixture of three fluorocarbon elastomers, the first having a Mooney viscosity at 121.degree. C. of at least 120, the second a Mooney viscosity at 121.degree. C. of 80 to 110, and the third a Brookfield viscosity at 100.degree. C. of 1,000 to 4,000 centipoises, in amounts 5 to 50%, 25 to 70% and 5 to 50% respectively, based on the weight of the polymeric component. The compositions can be easily molded under heat and pressure, and after they have been cured, they have remarkable resistance to degradation by hot liquids, even under pressure. Consequently, the compositions are very useful in the manufacture of self-regulating heaters for use in heating the production tubes of oil wells.

Abstract: An oil-filled electric cable in which the solid insulation is formed, at least in part, by separately applied, alternate layers of cellulose paper tape and of film tapes made of a plastic. Prior to application of the tapes around the cable conductor, the moisture content of the paper tape is selected and the swelling of the plastic tape by the oil after application is adjusted, if necessary, such as by immersing the plastic tape in the oil prior to application, so that the swelling of the plastic tape by the oil in the formed cable is offset by the shrinkage of the paper tape during drying of the cable. Also, apparatus for pre-swelling the plastic tape.

Abstract: A flexible shielded cable. The cable includes an elongate flexible metal conductor and a layer of a flexible dielectric material disposed about the conductor. The cable has a flexible metallic shield positioned about the dielectric with the shield including a copper foil having overlapping edges and a copper braid about the foil. A layer of metal bonds together the overlapping edges, bonds the braid and the foil and closes the openings of the braid. A method of forming a metallic shield is also disclosed.

Abstract: A cable sleeve for covering a cable splice. An enveloping hose of heat shrinkable material is on its inside provided with a hot melt adhesive coating. A device designed cross-shaped in cross-section for support of the cable ends is inserted between the cables. The device is of hot melt adhesive whose fusion point is below that of the material of the hot melt adhesive coating.

Abstract: A splice between two multiconductor cables is protected from ingress of water by a closure which contains a pressure means such as a bladder inside the closure capable of pressurizing a sealant present inside the closure to a pressure sufficient to force the sealant into the interstices of the splice and the interstices between the conductors in the cable, and maintaining the pressure until the sealant cures or hardens. The pressure means may also interact with seals at the end of the closure to seal the closure to the cable jacket.

Abstract: A method and apparatus for providing a sealed cable splice area is disclosed. The cable splice area is wrapped with an open cell spacer web. An adhesively coated liner is separately wrapped around the cable and the spacer web to form a pocket around the splice area. The pocket is filled with a cable encapsulating material which flows completely around the electrical conductors of the splice area. The filled pocket is then sealably wrapped to seal the cable splice area.

Abstract: This invention provides a fabric for RFI/EMI shielding wherein the fabric is woven, braided or warp knitted from yarns which comprise conductive fibers and non-conductive fibers wherein the conductive fibers comprise from about 10% to about 80% by weight of the fabric.

Abstract: Process for insulating by impregnation an electric winding with isocyanurate and oxazolidone cycles resins, in which one wraps around the conductors a glass cloth and porous mica paper tape loaded with a quaternary ammonium salt catalyzing the condensation of the isocyanate and epoxy compounds into isocyanurate and oxazolidone cycles, one impregnates the tape with a varnish containing an isocyanate compound and a liquid epoxy resin, then one subjects the impregnated tape to a varnish polymerization thermal treatment. One uses as a quaternary ammonium salt a benzyl-trialkylammonium halide with an alkyl chain containing at the most 3 carbon atoms.

Abstract: An improved electrical cable construction is provided wherein the metallic screen is coated with a protective coating which comprises a layer of a polymer selected for its properties of high flexural modulus, high tensile strength and high melting point and an adhesive layer comprising a random, block or graft copolymer of an olefin and a polymerizable, ethylenically unsaturated carboxylic acid, acid anhydride or derivative. Optionally, the adhesive layer may comprise a blend of the copolymer and a polyolefin.

Abstract: A splice between two multiconductor cables is protected from ingress of water by a closure which is filled with an expanding foam sealant which provides pressure inside the closure sufficient to force the sealant into the interstices of the splice and the interstices between the conductors in the cable, which pressure is retained in the closure until the sealant cures or hardens.