Patents Assigned to Pirelli S.p.A.
  • Method and apparatus for improving the dielectric strength of direct current cable insulation
    Patent number: 4540889
    Abstract: Method for improving the dielectric strength of insulation not subject to fluid pressure and used to insulate a conductor element, such as the conductor of a cable, an insulator, etc., subjected to direct current high voltage in which, during or prior to service use thereof, the insulation is subjected continuously or intermittently to a varying amplitude, direct current voltage. The amplitude of the variation is small relative to the average value of the direct current voltage and the frequency of the variation, preferably, is less than 60 Hz. Also, apparatus for providing the voltage of varying amplitude including an alternating current generator in series between the direct current source and the conductor element and inductor in parallel with the generator, the inductor having a low ohmic resistance and a high reactance relating, respectively, to the ohmic resistance and reactance of the generator.
    Type: Grant
    Filed: November 9, 1983
    Date of Patent: September 10, 1985
    Assignee: Societa' Cavi Pirelli S.p.A.
    Inventor: Paolo G. Priaroggia
  • Oil-filled, multi-core cable with at least one conductor differing from others
    Patent number: 4536610
    Abstract: An oil-filled, multi-core, electric cable having three cores within a metal sheath. Each core has a conductor surrounded by insulation and has substantially the same outer dimensions as the other cores. One conductor is made of copper and has a central oil duct. The other conductors are made of stranded aluminum wires in side-by-side and contacting relation and the ratio of the cross-sectional area of the metal of the copper conductor to the cross-sectional area of the metal of each aluminum conductor is the reciprocal of the ratio of the electrical conductivities thereof.
    Type: Grant
    Filed: June 18, 1984
    Date of Patent: August 20, 1985
    Assignee: Societa' Cavi Pirelli, S.p.A.
    Inventor: Alberto Giussani
  • Method and apparatus for forming grooves in an optical fiber support
    Patent number: 4528148
    Abstract: A method and apparatus for forming grooves in a reinforced, thermoplastic filament and for inserting optical fibers in the grooves. The reinforced filament is pulled longitudinally through a die having rollers corresponding to the number of grooves, and the rollers are pressed against the thermoplastic material to form the grooves. The rollers may be at room temperature or may be heated to temperature above room temperature and below the melting point temperature of the thermoplastic material. The fibers are inserted in the grooves as the filament leaves the die and preferably, the filament is wrapped with a binding, e.g. a tape, after the fibers are inserted in the grooves so as to seal the grooves.
    Type: Grant
    Filed: June 21, 1982
    Date of Patent: July 9, 1985
    Assignee: Societa' Cavi Pirelli S.p.A.
    Inventor: Enrico Dotti
  • Sheathed, multi-core, oil filled, electric cable with oil duct exterior to the cores
    Patent number: 4523648
    Abstract: An electric cable having a fluid-tight, metal sheath containing a plurality of cores without oil ducts, each including a conductor surrounded by insulation, and a separate tubular member adjacent and contacting two of the cores and having an oil duct of a cross-sectional area at least equal to the cross-sectional area of the sum of the oil duct cross-sectional areas normally included in each core. The spaces between the tubular member and the cores and between the cores, the tubular member and the sheath are filled with an insulating filler, and the insulation of the cores and the filler are impregnated with an insulating oil and the duct of the tubular member is filled with the insulating oil. The sheath contacts the outer surfaces of the tubular member and the cores, and the oil duct of the tubular member contains a plurality of longitudinally spaced, oil flow restrictors.
    Type: Grant
    Filed: February 9, 1984
    Date of Patent: June 18, 1985
    Assignee: Societa Cavi Pirelli S.p.A.
    Inventors: Francesco Strada, Giuseppe Bazzi
  • Method and apparatus for laying-up cores of a multi-core electric cable
    Patent number: 4519197
    Abstract: In the laying-up of the cores of a multiple core cable in which the cores travel from a plurality of auxiliary platforms rotatably mounted on a main, rotatable platform to a laying-up member, the platforms are rotatable by separate motor drives, one for each platform, and the cores operate position sensors intermediate the auxiliary platforms and the laying-up member so as to speed up or slow down the motor drives for the auxiliary platforms dependent upon the positions of the cores as they pass from the auxiliary platforms to the laying-up member thereby eliminating residual torsion in the cores of the cable.
    Type: Grant
    Filed: March 19, 1984
    Date of Patent: May 28, 1985
    Assignee: Societa Cavi Pirelli S.p.A.
    Inventor: Andrea Borroni
  • Mounting-rim for tires and its assembly with corresponding tire
    Patent number: 4502521
    Abstract: The device is composed of a series of two or more substantially circular protuberances that are eccentric with respect to the rim axis, and formed on the mounting rim in an axially inner position with respect to the bead seat, creating a confining space adjacent the bead seat and radially outwardly projecting with respect to it, so as to constitute a limit to the axial shifting of the tire bead heel towards the central well of the rim.
    Type: Grant
    Filed: March 30, 1983
    Date of Patent: March 5, 1985
    Assignee: Societa Pneumatici Pirelli S.p.A.
    Inventors: Giuseppe Tavazza, Maurizio Boiocchi
  • Process for laying a submarine cable
    Patent number: 4498812
    Abstract: An underwater electric power cable which has a minimum radius of curvature to which it can be bent without damage and which can be suspended between underwater suspension points in no greater than a predetermined length for a desired service life is layed by first laying a flexible steel rope along the desired underwater course and adjusting the rope position and length so that there are no curvatures thereof less than the minimum radius and no lengths thereof greater than the predetermined length, and then, the cable is layed alongside the rope so as to follow the configuration of the rope.
    Type: Grant
    Filed: February 22, 1983
    Date of Patent: February 12, 1985
    Assignee: Societa' Cavi Pirelli S.p.A.
    Inventors: Gianmario Lanfranconi, Giuseppe Monti
  • Apparatus for manufacturing an optical fiber cable with optical fibers in grooves in the cable core
    Patent number: 4497164
    Abstract: Apparatus for inserting optical fibers into helical grooves in a plastic core advanced through a rotatable, rigid body which has conduits for guiding the fibers from bobbins mounted on a rotatable cage into the grooves, the ends of the conduits engaging the walls of the grooves which cause the body to rotate as the core is advanced, said apparatus having drive means for advancing the core separate from the drive means for the rotatable cage and having detecting and control means for detecting angular and direction of rotation differences between the cage and the rigid body and correcting such differences by control of the rotation of the cage by its drive means.
    Type: Grant
    Filed: May 25, 1983
    Date of Patent: February 5, 1985
    Assignee: Societa'Cavi Pirelli S.p.A.
    Inventors: Enrico Dotti, Beniamino Mariani
  • Flameproof electric cable impregnated with insulating fluid
    Patent number: 4491684
    Abstract: A flameproof electrical insulating fluid and an electrical cable impregnated with such fluid, the insulating fluid being a mixture of a polymethylsiloxane having a viscosity greater than 5 centistokes at 25.degree. C. and an aromatic compound corresponding to the chemical formula: ##STR1## where R is an aliphatic radical and said aromatic compound is present in the mixture in an amount from 0.5% to 10% by weight of the total weight of the mixture. Preferably, the aromatic compound is isopropyldiphenyl.
    Type: Grant
    Filed: April 29, 1983
    Date of Patent: January 1, 1985
    Assignee: Societa Cavi Pirelli S.p.A.
    Inventor: Bernardino Vecellio
  • Electric cable with insulation of biaxially oriented, polymeric tape with a coating of grease
    Patent number: 4481259
    Abstract: A direct current electric cable has its conductor insulation formed by winding a tape of a biaxially oriented polymer provided on at least one face with a film of water-repellent grease.
    Type: Grant
    Filed: October 6, 1983
    Date of Patent: November 6, 1984
    Assignee: Societa Cavi Pirelli S.p.A.
    Inventor: Bernardino Vecellio
  • Starter for internal combustion engine
    Patent number: 4471733
    Abstract: A mechanical starter for internal combustion engines in which the energy necessary to start the internal combustion engine is provided by elastomeric elements which are stretched by winding them around a nucleus composed of a plurality of mutually contacting washers is disclosed.
    Type: Grant
    Filed: January 29, 1982
    Date of Patent: September 18, 1984
    Assignee: Industrie Pirelli S.p.A.
    Inventors: Giorgio Tangorra, Lino Magnabosco
  • Camouflage covering for snowy soils
    Patent number: 4469745
    Abstract: A camouflage covering for snowy soils is constituted by a sheet of a polar polymer containing a filler based on titanium salts, silicates or silicon dioxide, either alone or mixed together.
    Type: Grant
    Filed: June 17, 1983
    Date of Patent: September 4, 1984
    Assignee: Industrie Pirelli S.p.A.
    Inventor: Pier L. Robicci
  • Power transmission belt
    Patent number: 4457743
    Abstract: A power transmission belt which is substantially V-shaped in cross-section has insert members which are resistant to transverse compression embedded in an elastomeric or plastomeric body. Protective layers of elastomer or plastomer having oriented fibers dispersed therein cover the flanks of the belt and, if necessary, are disposed in addition to the belt body adjacent to a base of the belt.
    Type: Grant
    Filed: February 23, 1982
    Date of Patent: July 3, 1984
    Assignee: Industrie Pirelli S.p.A.
    Inventors: Edoardo Robecchi, Renato Dell'Orto
  • Optical fiber element with three layer protective covering
    Patent number: 4448484
    Abstract: An optical fiber element comprising an optical fiber surrounded and protected from mechanical stresses by three layers of plastic material, the intermediate layer having a modulus of elasticity substantially less than the moduli of elasticity of the adjacent inner and outer layers and less than one Kilogram/mm.sup.2.
    Type: Grant
    Filed: March 31, 1982
    Date of Patent: May 15, 1984
    Assignee: Societa Cavi Pirelli S.p.A.
    Inventors: Aurelio Lombardi, Elio Occhini
  • Toothed belt
    Patent number: 4445879
    Abstract: The present invention relates to a toothed belt provided with an undulated fabric embedded in the part of the belt's body between its tension resistant insert member and its back. The elastomeric material of the toothed belt disposed between the undulated fabric and the back has a lesser hardness than that forming the remaining part of the belt.
    Type: Grant
    Filed: April 27, 1981
    Date of Patent: May 1, 1984
    Assignee: Industrie Pirelli, S.p.A.
    Inventor: Mario Cicognani
  • Energy accumulator and internal-combustion engine starter comprising said accumulator
    Patent number: 4441466
    Abstract: This invention provides an accumulator of mechanical energy and a starter for an internal-combustion engine actuated by energy from the accumulator. The energy is stored by elastically extensible elastomeric elements wound circumferentially around supports disposed according to the generatrices of a cylindrical member.
    Type: Grant
    Filed: March 25, 1982
    Date of Patent: April 10, 1984
    Assignee: Industrie Pirelli S.p.A.
    Inventor: Giorgio Tangorra
  • Apparatus for producing metallic cords in layers
    Patent number: 4437297
    Abstract: Apparatus for producing metallic cords having layers of wires twisted around a wire core, with great efficiency and low costs, of the outer collection kind, comprises two double-twist cabling machines in series, mutually co-axial and joined together in such a way that the ratio of the rotational velocities of two cages differ and can be changed while the apparatus is in operation.
    Type: Grant
    Filed: February 23, 1982
    Date of Patent: March 20, 1984
    Assignee: Societa' Pneumatici Pirelli S.p.A.
    Inventor: Alberto Vespasiani
  • Annular reinforcing structure of radial tires
    Patent number: 4420025
    Abstract: An annular reinforcing structure for vehicle tires of a radial carcass has at least two radially superimposed layers of metal cords having an elongation at break between 2.6% and 3.2%. Two reinforcing rings are disposed in a radially external position at the extremities of the layers of metal cords with the axially outer edges coinciding with each other. The rings have a width between 7% and 40% of the width of the radially inner layers, and comprise metal cords having an elongation at break between 4% and 8%. The metal cords are oriented according to the longitudinal direction of the tire and are disposed in at least two radially superimposed strips.
    Type: Grant
    Filed: October 1, 1980
    Date of Patent: December 13, 1983
    Assignee: Industrie Pirelli S.p.A.
    Inventors: Giuliano Ghilardi, Luigi Maiocchi
  • Pneumatic tire for motor vehicles having a tread pattern which adapts the tire for good performance and low road noise
    Patent number: 4416317
    Abstract: A pneumatic tire for a motor vehicle has a tread band having at least two longitudinal grooves which divide it into a plurality of circumferential ridges, and a series of circumferentially spaced axial grooves which divide the two outermost ridges into blocks. The edges of the inner ridges are provided with blind, oblique slits, all inclined in the same sense with respect to the circumferential direction of the tire. The slits are substantially parallel to one another and are preferably offset with respect to each other.
    Type: Grant
    Filed: December 1, 1981
    Date of Patent: November 22, 1983
    Assignee: Societa' Pneumatici Pirelli S.p.A.
    Inventor: Renato Caretta
  • High voltage direct current cable with impregnated tape insulation
    Patent number: 4417093
    Abstract: A direct current, electric, submarine cable which may be used in long lengths and at great depths and which has improved voltage breakdown characteristics with respect to voids which form in the insulation. The cable has a conductor surrounded by an inner semi-conductive screen which is surrounded by cellulose paper tape insulation which is surrounded by an outer semi-conductive screen which is surrounded by a metal sheath. The paper tape is impregnated with a compound comprising a viscous hydrocarbon oil containing a substance having polar groups, the amount of the substance being sufficient to make the volume resistivity of the compound 100 times lower than the volume resistivity of the tape with the compound therein.
    Type: Grant
    Filed: December 4, 1981
    Date of Patent: November 22, 1983
    Assignee: Societa Cavi Pirelli S.p.A.
    Inventors: Elio Occhini, Gianmario Lanfranconi, Piero Metra