Abstract: A weathershed for use in a composite insulator includes a molded polymer body. The body configuration is such that the leakage distance across the weathershed is increased, while at the same time the amount of material needed is reduced. This provides a lightweight and easily manufactured weathershed. The weathershed includes a radially curved outer edge which reduces the electric field gradient and also reduces the tendency to trap contaminants.

Abstract: The invention concerns a bushing device (12) designed to be fitted through a hole in a wall including a body (20) and a cover (18) each adapted to be disposed on one side of the wall and rod and connection (14, 16) for connecting the body (20) and the cover (18) to grip said wall between them, the body (20) and the cover (18) including aligned passages (22, 47) adapted to receive a conductive rod (14). The cover (18) includes an inner core (44) delimiting the passage (47) for receiving the rod (14) and an outer sheath (46) covering the lateral wall of the inner core (44), the inner core (44) and the outer sheath (46) being made of different materials.

Abstract: A composite insulation of S2 glass fibers and epoxy is formed having a more nearly uniform coefficient of thermal expansion in all three planes for use in cryogenic superconductor applications. The glass fibers have a three-dimensional weave.

Abstract: An end fitting having a bore that forms a sleeve for the shank of an electrical insulator of composite structure. The bore has a substantially frustoconical wall that flares away from the bore opening towards the end wall of the bore and has an annular swelling directed towards the inside of the bore. This complex shape for the wall of the bore contributes to reinforcing the strength of the fixing between the end fitting and the shank by interference due to heat shrinking.

Abstract: An electrically insulating supporting structure for a high voltage electric apparatus having a high voltage charging part and a ground potential part, the structure being adapted to be disposed between the high voltage charging part apparatus and the ground potential part. The structure includes an organic insulating structure formed in a predetermined shape, and an inorganic insulating layer formed on a surface of the organic insulating structure and an intermediate layer consisting essentially of an organic and an inorganic powder.

Abstract: The present invention relates to a pole head for supporting conductors on poles for medium- and high-voltage overhead power lines, having at least one tubular portion which has a structural function, is made of electrically insulating composite material, and is fixed to a supporting structure. Coupling flanges for supporting the electrical conductors are connected to the at least one tubular portion and are mutually spaced along the axis of the tubular portion.

Abstract: A composite insulator includes a hollow and tapered core portion composed of fiber-reinforced plastics, and a sheath and sheds composed of an insulating polymeric material integrally molded on the outer surface of the core portion. The core portions of composite insulators for a plurality of voltage classes are formed by using a mandrel assembly in which a plurality of mandrel members are combined. The so-prepared core portion is placed within a mold unit in accordance with the voltage class of the composite insulator to be manufactured, and the insulating polymeric material is poured into the mold cavity to integrally mold the sheath and the sheds.

Abstract: A bushing for an electrical high-frequency signal, with at least one conductive element carrying the electrical high-frequency signal, with at least one mechanical supporting element and with at least two insulating elements between the conductive element and the supporting element that perform different functions. The bushing for an electrical high-frequency signal is designed so that the impedances of the insulating elements are basically identical.

Abstract: A reinforced electrical insulator has a load sustaining mechanical core with a pair of attachment members located at its longitudinal ends. One of the attachment members extends longitudinally into the mechanical core to provide reinforcement to the mechanical core. The mechanical core member is constructed of a rigid, dielectric material with a first end section, a second end section, and a center section. A plurality of weathersheds extending outwardly from the center section of core member in a substantially radial direction relative to the longitudinal axis. The first and second end sections having maximum widths which are larger than the maximum width of the center section. The attachment members have inner portions embedded within the end sections of the core and outer portions extending outwardly from the end sections of the core.

Abstract: An electrical insulator in the form of a pintype insulator has a load sustaining mechanical core and a dielectric sheath overlying the mechanical core to protect the mechanical core from the weather. The mechanical core is constructed of a load sustaining dielectric material which is different from the dielectric material of the sheath. The mechanical core has a profiled outer surface with a top groove, two side grooves, an annular rib and an axially extending threaded bore. The dielectric sheath is applied over the mechanical core as thin as practical to minimize the amount of sheath material being used. However, the dielectrical sheath is molded on the mechanical core to form a pair of weathersheds which can either extend radially outwardly therefrom or substantially downwardly therefrom in the form of vertical sheds.

Abstract: The disclosed polymer LP insulator having an FRP rod, an insulation overcoat member made of rubber, which is arranged on an outer surface of the FRP rod, and securing metal members clamped at both end portions of the FRP rod, wherein an end portion of the insulation overcoat member is inserted into an end portion of the securing metal member, includes an elastic member arranged in a space defined by the FRP rod, an inner surface of the securing metal member, and an end surface of the insulation overcoat member, wherein a pressure for clamping and fixing is only applied to a connection portion between the securing member and the FRP rod.

Abstract: An improved high voltage insulator includes a central core and an insulating body fitted tightly around the central core. A flexible coating layer is interposed between a part of the central core and the insulating body. The flexible coating layer fills in shrinkage cavities and compensates for a retraction effect caused by injected material used in forming the insulating body. The insulating body is overmolded to the central core previously coated with the flexible coating layer with an injected insulating resin such as a thermoplastic or thermosetting resin. The insulator could be used as a capactive divider or bushing insulator.

Abstract: The electric isolator (1) is manufactured from a support (2) made of laminated material and a continuous band made of elastomeric material (3) wound in several contiguous successive turns around the support on an outer face (20) thereof so as to make an isolating coating in the form of a plurality of annular flanges (16, 17, 18). The continuous band is profiled so as to have, in section, a basis used as a contact surface with the support outer surface, an upper face provided with at least one flange extending transversally to the basis, a first and a second side surfaces which continue the basis by forming a certain angle therewith.

Abstract: Insulating and anticorrosive composition for electrical devices consisting of two semifluid components that are mixed together at the time of application, whereinA) the first component includesfrom 20 to 35 parts (w/w) of a bitumen having a softening point of at least 90.degree. C.,from 1.5 to 7 parts (w/w) of a hydrocarbon resin,from 0.5 to 5 parts (w/w) of an alkylbenzene,from 35 to 60 parts (w/w) of resin oil, andfrom 10 to 30 parts (w/w) of olein,B) the second component includesfrom 40 to 60 parts (w/w) of a mixture of partially hydrogenated terphenyls and quaterphenyls,from 0.5 to 5 parts (w/w) of a styrene/butadiene block copolymer,from 5 to 30 parts (w/w) of calcium oxide, andfrom 10 to 50 parts (w/w) of calcium hydroxide.

Abstract: A heat shrinkable shed (2) is mounted on a power cable (12) and sealed thereto by a hot-melt adhesive (10). Four projections (8) are equispaced around the interior surface of the shed (2) to penetrate the adhesive (10) and to engage the outer surface of the cable (12) to enhance the longitudinal retention of the shed (2) on the cable (12), particularly under conditions of thermal cycling.

Abstract: The invention provides for a method of molding an elastomeric material which avoids longitudinal mold lines and an improved molding composition as well as molded parts for hybrid insulators and the like.

Abstract: A composite insulator having a core member and a housing member integrally arranged around the core member, the housing member being constructed by a trunk portion and a shed portion, has a creepable distance extending means arranged on a lower plane of the shed portion. Moreover, a segment used for producing the composite insulator has a pair of segment molds detachably connected at a partition plane having a through-hole at its center portion through which the core member is arranged, an upper plane forming portion arranged at its one end surface for defining an upper plane of the shed portion, and a lower plane forming portion arranged at its other end surface for defining a lower plane of the shed portion; and a partition for forming the creepage distance extending means arranged at the lower plane forming portion.

Abstract: The present invention relates to a barrier for an insulator having a central portion or stem with a plurality of sheds extending therefrom. The barrier is, in use, located between adjacent sheds of the insulator and includes a sheet of dielectric material having one or more discontinuities in its surface. The discontinuities can be in the form of holes in the surface or in the form of a joint between cut edges of the barrier.

Abstract: A composite electrical insulator includes a metal fitting (3, 4) fixedly secured to a fiber-reinforced plastic rod (1) at one end thereof. The rod has a stress-relieved zone (8) situated opposite to the metal fitting (3, 4), and formed by a heat treatment of the rod (1) after an end portion of the rod (1) has been inserted into a bore (5) in the metal fitting (3, 4) and the metal fitting (3, 4) fixedly secured to the rod (1). The heat treatment of the rod (1) is performed at a temperature which is not lower than a heat transition temperature of a matrix resin of the fiber-reinforced plastic material.

Abstract: A composite electrical insulator (1) includes a plastic rod (2), e.g., an FRP rod, which is covered by a sheath which includes a resilient and electrically insulating material. A metal fitting (4, 5) on each side of the insulator (1) has a radially inwardly deformable sleeve portion formed with a bore in which the end portion of the plastic rod (2) is covered by the sheath (3). The end portion of the sheath (3) has an outer surface opposite to the metal fitting (4, 5), which is provided with at least one circumferential ridge (7a, 7b).

Abstract: A metal fitting for a composite electrical insulator (1) including a plastic rod (2), e.g., an FRP rod. The metal fitting (4) includes a radially inwardly deformable sleeve portion having a bore (5) into which an end portion of the rod (1) can be inserted for fixedly securing the metal fitting (4) to the rod (1). The bore (5) in the metal fitting (4) has an inner surface which is formed with fine protrusions (7). These protrusions (7) provide a satisfactory resistivity to the tensile force applied to the insulator (1), to thereby effectively prevent withdrawal of the rod (2) from the metal fitting (4) when it is in use.

Abstract: A composite link and insulator, and method of construction, includes a fiberglass body. The body is formed by coating glass fibers with a liquid resin and winding the fibers around a plurality of tubular fittings or bushings in two layers, a first extending longitudinally of the body and the second transversely and around the first. A polymer shield layer and weathersheds are injection molded over the fiberglass body to create an insulator. The insulator may also be provided with stiffening plastic inserts at either end for increasing strength without adding significantly to the insulator's overall weight.

Abstract: An electrical insulator comprising a cylindrical core (2) of an insulating refractory material, such as porcelain, onto a portion of the curved surface of which a sleeve (8) of insulating polymeric material is fitted. Metal end-caps (4), for electrically connecting the insulator, are fitted to the ends of the porcelain core such that there is an exposed portion (10) of the curved surface of the core between the sleeve and each end-cap. Thus, any damaging electrical activity which takes place at the metal end-caps is directed primarily onto the surface of the porcelain core (2), and not onto the surface of the electrically vulnerable polymeric sleeve (8), which serves to protect mechanically the relatively brittle porcelain core. Optionally, the polymeric sleeve (8) may have a convoluted or a shedded outer surface (12) to increase the leakage path length of the insulator, or to prevent the formation of a continuous moisture path, or both.

Abstract: A composite link and insulator, and method of construction, includes a fiberglass body. The body is formed by coating glass fibers with a liquid resin and winding the fibers around a plurality of tubular fittings or bushings in two layers, a first extending longitudinally of the body and the second transversely and around the first. A polymer shield layer and weathersheds are injection molded over the fiberglass body to create an insulator.

Abstract: An electrical assembly, such as an insulator or a surge arrester, utilizing a pair of end collars for coupling an elastomeric weathershed housing to a pair of metallic end fittings, and for reducing electrical stress at the interface of the ends of the weathershed housing and the end fittings, and for sealing the ends of the weathershed housing to the end fittings. In particular, a radially directed force is applied to the weathershed housing by insertion of the core member into the axial bore of the weathershed housing causing radial outward expansion of the weathershed housing into intimate contact with the end collars. Also, each of the ends of the weathershed housing is held in contact against the inner end of the respective end fitting to seal the interface therebetween. Accordingly, a watertight seal is created at the interface between each of the end fittings and the ends of the weathershed housings.

Abstract: An electrical cutout with a modular product design is provided with a constructional configuration for the insulator wherein the insulator is light in weight, has sufficient mechanical strength, can be readily injection molded, and wherein the creep distance is statistically maximized. The electrical cutout has an insulator, an upper and lower line terminal assembly, and a fuse assembly. The insulator has an elongated central stem portion defining a longitudinal direction, and a plurality of longitudinally spaced apart skirts mounted to the stem portion and so as to lie in respective transverse planes which are perpendicular to the longitudinal direction. The elongated central stem portion of the insulator has a non-solid cross-sectional configuration.

Abstract: A composite insulator (30) comprises a central rod (32) of fibers embedded in a synthetic resin with each end of the rod being fixed to a respective metal end-fitting (31) by a metal sleeve coupling (34) and with the side wall of the rod having a coating (36) of elastomer fins molded thereover. The coating covers the side walls (37) of the end-fittings (31) so as to leave uncovered only those portions (35) which are required for attaching the insulator.

Abstract: An insulator of the type composed of a core onto which a skirt made of insulating material and provided with fins is molded. The core comprises an axial rod of a composite material onto whose ends the end sleeves of mounting terminals are swaged.The rod comprises a web of longitudinal, parallel fibers bonded by thermosetting resin and encased in a braided or woven envelope like covering. A mounting terminal is connected to an end of the rod by a combination of uniformly distributed radial locking of the sleeve onto the rod and by penetration of the metal of the sleeve into gaps between the fibers of the envelope like covering.

Abstract: An electrical assembly, such as an insulator or a surge arrester, utilizing a pair of end collars for coupling an elastomeric weathershed housing to a pair of metallic end fittings, and for reducing electrical stress at the interface of the ends of the weathershed housing and the end fittings, and for sealing the ends of the weathershed housing to the end fittings. In particular, a radially directed force is applied to the weathershed housing by insertion of the core member into the axial bore of the weathershed housing causing radial outward expansion of the weathershed housing into intimate contact with the end collars. Also, each of the ends of the weathershed housing is held in contact against the inner end of the respective end fitting to seal the interface therebetween. Accordingly, a watertight seal is created at the interface between each of the end fittings and the ends of the weathershed housings.

Abstract: An electrical assembly, such as an insulator or a surge arrester, utilizing a plurality of elastomeric weathershed housings for enclosing a core member therein. The elastomeric weathershed housings are coupled and sealed together by an insulating collar. A radially directed force is applied to the collar or the weathershed housings to cause intimate contact between the collar and the end portions of the weathershed housings to provide a weathertight seal. In the preferred embodiment, the radially directed force is provided by insertion of the core member into the axial bore of the weathershed housings causing radial outward expansion of the weathershed housings into intimate contact with the insulating collar. In another embodiment, the radially directed force is provided by a heat shrinkable insulating collar, which is shrunk about the end portions of adjacent weathershed housings. The core member can be an insulating rod or a plurality of electrical components, such as metal oxide varistors.

Abstract: A high voltage porcelain insulator has a plurality of sheds extending laterally thereof at spaced apart locations therealong. The creepage path length of the shedded insulator is extended by mounting polymeric insulating creepage extenders on the porcelain sheds. The creepage extenders do not extend completely around the periphery of the sheds but leave a gap. Preferably the gaps of adjacent creepage extenders along the insulator are not aligned.

Abstract: A rigid electrical insulator of the type having a base or a pin at its bottom and having at least one groove (18 or 19) for receiving an electrical cable at its top, the insulator being characterized by the fact that it includes at least one central rod (1) fixed at its bottom end to the base (5) or to the pin and at its top end to a rigid head (7) provided with at least one channel (8 or 9), the outside faces of the rod and of the rigid head (7) being covered in waterproof manner by a covering (10), with the head covering being of a flexible elastomer and the rod covering being selected from elastomers, resins, and varnishes, the groove (18 or 19) being defined by the channel (8 or 9) covered by its covering.

Abstract: An elongated electrically insulating support structure, for use by itself as an electrical insulator or for use as a strength member in a composite electrical insulator made of fiberglass-reinforced resin, comprising a central cylindrical body and ends having the shape of solids with surfaces of revolution with axial symmetry, having diameters larger than the diameter of the central cylindrical body, with which they are radiused without solution of continuity, i.e., connected without and discontinuity, wherein the central cylindrical body and the ends consist of superimposed and crossed layers of glass filament impregnated with thermosetting resin, wound around a cylindrical element with a helical winding angle smaller than 90.degree..

Abstract: A method of producing a ceramic insulating bushing to be filed with dielectric gas under pressure and which is free from any risk of explosion, comprising the following operations:(1) manufacturing a ceramic bushing (10) having an inside surface which is conical over the entire length (L1) of the bushing;(2) making a conical sleeve (30) of strong insulating material, the sleeve having the same cone angle as the inside surface of the bushing and having a length (L2) which exceeds that of the bushing;(3) inserting the sleeve (30) into the bushing until it makes contact with the entire inside surface (20) of the bushing (10); and(4) cutting off the sleeve at the ends of the busing.

Abstract: The invention provides an electrical insulator comprising a cylindrical core (2) of an insulating refractory material, such as porcelain, onto a portion of the curved surface of which a sleeve (8) of insulating polymeric material is fitted. Metal end-caps (4), for electrically connecting the insulator, are fitted to the ends of the porcelain core such that there is an exposed portion (10) of the curved surface of the core between the sleeve and each end-cap. Thus, any damaging electrical activity which takes place at the metal end-caps is directed primarily onto the surface of the porcelain core (2), and not onto the surface of the electrically vulnerable polymeric sleeve (8), which serves to protect mechanically the relatively brittle porcelain core. Optionally, the polymeric sleeve (8) may have a convoluted or a shedded outer surface (12) to increase the leakage path length of the insulator, or to prevent the formation of a continuous moisture path, or both.

Abstract: An insulator housing comprising a resin bonded fibre tube carrying water repellent, spirally arranged inner sheds and water sheds made from strips of polymeric material provides improved outdoor electrical insulation. The insulator housing provides greater insulation performance per unit length of housing than prior art structures.

Abstract: A high voltage insulator that has a helical configuration in which successive turns are axially spaced apart, and an exposed surface of insulating and substantially non-tracking material. The helical configuration provides a long creepage path length and an ability to shed water. The insulator is sufficiently rigid for it to provide a support, for example, for a high voltage cable or for a fibre optic cable.

Abstract: A high voltage porcelain insulator having a glaze applied to at least a head portion of the insulator which head portion is covered by a metal fitting and a cement. The glaze essentially consists of, in terms of weight, from 64.0 to 68.0% of SiO.sub.2, from 17.5 to 19.0% of Al.sub.2 O.sub.3, from 5.0 to 6.5% of MgO, not more than 3.0% of CaO, from 2.0 to 2.8% of K.sub.2 O and Na.sub.2 O in a total amount, and from 3.0 to 9.0%, when calculated as MnO, a compound which is converted to MnO and or MnO.sub.2 after being fired at a temperature range suitable for firing porcelain.

Abstract: A high performance, high voltage electrical insulator, for use at greater than 15 Kv in wet, contaminated conditions, is designed to give a minimum surface area while maintaining a low leakage current by specifying the ratios of shed diameter to shed pitch, leakage distance between support fittings to the straight line distance between support fittings, and the shed diameter to the support rod diameter. Through the use of specified silicone elastomeric compositions, or through the use of silicone compositions meeting specified electrical properties, an insulator meeting the design specifications is shown to be a useful high voltage insulator.

Abstract: A high voltage composite member, such as a support insulator or a bushing, comprises a core and a sheath of elastomeric material vulcanized to the core and at least one module of elastomeric material having an external shed and an inner cylindrical surface of predetermined normal diameter. The sheath has circumferentially continuous external bulges overlapping and engaging the ends of the inner surface to hold the module permanently in a desired location on the sheath, the module being substantially free of deforming stress. A sealing material provides a sealed interface between the module and sheath.

Abstract: A tubular article has an outer component of insulating material having a convoluted outer surface, and an inner component of stress grading material. In another embodiment, a tubular article has an outer component of insulating material having an outer surface that is convoluted along part of its length and shedded along another part of its length. The articles may be of heat-shrinkable polymeric material. The articles are particularly useful for terminating high voltage electric cables, and in the manufacture of electrical insulators.

Abstract: Dielectric materials having low dielectric constant are provided, the materials comprising fabrics impregnated with thermosetting resins, at least a portion of the fibers in the fabrics being fluorocarbon fibers. Also provided is a method of manufacture of these dielectric materials. The dielectric materials are useful in the fabrication of multilayer printed circuit boards.

Abstract: Due to aging of the insulating materials arranged between the electrodes in ionization fire alarms or detectors the insulating efficiency of these thus formed so-called insulating paths or spans deteriorates in the course of time despite, or maybe even due to the cleaning operations performed upon such ionization fire alarms. To ensure that the insulating capacity does not fall below a critical value the insulating path or span is formed by at least two different insulating materials. The materials are arranged in such a manner that the creepage path between the electrodes extends across all the different insulating materials. This principle also may be applied to other measuring devices which require a high input resistance of an amplifier stage.

Abstract: A high voltage bushing has a central conductor which is surrounded by an insulation bushing core. The outer end of the conductor is bare and extends beyond the end of the bushing core. A mounting flange is also secured to the bushing core. One end of a hollow porcelain weathershed is fitted over the outer end of the central conductor and bushing core and seats against the mounting flange and defines an annular volume between the interior of the porcelain weathershed and the exterior of the bushing core. The bushing core is tapered down toward its end so that the annular volume within the weathershed has a tapered outer surface. The free end of the porcelain weathershed receives a bushing cap which seals the annular volume and can be bolted against the porcelain weathershed by a nut which is threaded onto the outer end of the conductor.

Abstract: A reinforced protective housing that may be utilized for protection of electrical contacts; such housing is reinforced with cured resin-coated open mesh glass cloth. Electrical contacts are incorporated into the glass cloth reinforced plastic body to form a unitary electrical connector component. A method of manufacturing cured resin-coated open mesh glass cloth reinforced molded plastic electrical connectors.

Abstract: High voltage porcelain insulator comprises, a porcelain body, and a glaze applied on at least a surface of the porcelain body, said porcelain body having a specific resistivity .rho..sub.p of .rho..sub.p .gtoreq.5.0.times.10.sup.13 .OMEGA..cm, and said glaze having a specific resistivity .rho..sub.g of .rho..sub.g <.rho..sub.p.

Abstract: An electrical insulator component comprises a one-piece block of moulded fins (11, 12, 13) disposed around an insulating core (10). The surface of the block of fins includes a moulding line (21, 22, 23) and said moulding line has arcuately displaced segments in that the portion 22 extends circumferentially while the portions 21 and 23 extend longitudinally but in different planes. The net result is that dirt building up along the join line does not form a continuous straight-line low resistance path for leakage currents.

Abstract: An electrical insulator for use in dirty or wet environments. The insulator has a substantially cylindrical outer peripheral surface upon which is disposed a plurality of water-repellent oil-bleeding insulation bonds formed of a silicone rubber containing a water-repellent silicone oil. The bands are fitted onto the insulator surface so that they extend perpendicular, parallel or oblique to the longitudinal axis of the insulator. The bands each may be in the form of a hollow belt with a clamp band passing through the interior thereof for clamping the belt to the outer peripheral surface of the insulator.

Abstract: The invention comprises a bushing surrounding an electrical conductor, including a porcelain tube which employs a gaseous insulator, an insulating tube disposed with a space of small volume set relative to the inner periphery of the porcelain tube, the small space being filled with an insulating medium which is deformable with a predetermined force. According to the construction, when the porcelain tube has been damaged, its fragments can thus be prevented from scattering far. The flashover of the bushing can be prevented by disposing compression springs in the lower part of the insulating tube, and the electric field distribution of the outer surface of the bushing can be improved by coating the surface of the insulating tube with an electrically-conductive coating material.

Abstract: An electrical insulator assembly and method of manufacturing same, having a generally cylindrical or conical body portion formed of a breakable cast solid insulation system and a reinforcing member having a corrugated configuration and formed of a web or mesh type reinforcing fabric. When the breakable body member has been broken, the corrugated configured reinforcing web member provides a path of escape for pressurized insulating fluid while limiting the movement of body member fragments in the direction of escape of the pressurized fluid.