US3419060A - Textile cord material and pneumatic tires manufactured therewith - Google Patents

Textile cord material and pneumatic tires manufactured therewith Download PDF

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Publication number
US3419060A
US3419060A US409598A US40959864A US3419060A US 3419060 A US3419060 A US 3419060A US 409598 A US409598 A US 409598A US 40959864 A US40959864 A US 40959864A US 3419060 A US3419060 A US 3419060A
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US
United States
Prior art keywords
cord
cords
pneumatic tires
cord material
textile cord
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US409598A
Inventor
Goy Ronald Stansfield
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Dunlop Rubber Co Ltd
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Dunlop Rubber Co Ltd
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Publication date
Application filed by Dunlop Rubber Co Ltd filed Critical Dunlop Rubber Co Ltd
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Publication of US3419060A publication Critical patent/US3419060A/en
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Classifications

    • D—TEXTILES; PAPER
    • D02—YARNS; MECHANICAL FINISHING OF YARNS OR ROPES; WARPING OR BEAMING
    • D02G—CRIMPING OR CURLING FIBRES, FILAMENTS, THREADS, OR YARNS; YARNS OR THREADS
    • D02G3/00—Yarns or threads, e.g. fancy yarns; Processes or apparatus for the production thereof, not otherwise provided for
    • D02G3/44—Yarns or threads characterised by the purpose for which they are designed
    • D02G3/48—Tyre cords
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
    • B60C9/0042—Reinforcements made of synthetic materials
    • D—TEXTILES; PAPER
    • D03—WEAVING
    • D03D—WOVEN FABRICS; METHODS OF WEAVING; LOOMS
    • D03D11/00—Double or multi-ply fabrics not otherwise provided for
    • D—TEXTILES; PAPER
    • D10—INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES
    • D10B—INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES
    • D10B2331/00—Fibres made from polymers obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polycondensation products
    • D10B2331/04—Fibres made from polymers obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polycondensation products polyesters, e.g. polyethylene terephthalate [PET]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S57/00—Textiles: spinning, twisting, and twining
    • Y10S57/902—Reinforcing or tire cords

Definitions

  • My invention relates to textile cord material and to pneumatic tires manufactured therewith.
  • the filamentary size is usually kept to a minimum in view of the fact that spinning of the filaments is more convenient with a thin filament than with a thick one and, furthermore, the finished yarn is of ifiner texture which is more suitable for most purposes.
  • heat treatment is also carried out so as to prevent subsequent shrinkage of the material upon heating during vulcanisation and so as to set the material thus stabilizing its length.
  • a synthetic textile filamentary cord comprises a plurality of filaments or monofilaments, having a denier greater than 10, twisted together, the cord having been heat-stretched to increase the tensile modulus of the cord and to increase the resistance of the cord to buckling under an axial compression load.
  • a pneumatic tire comprises a tire building element, e.g. a rigid breaker, carcass, and a filler or chafer, incorporating synthetic textile filamentary cords as defined in the preceding paragraph.
  • a tire building element e.g. a rigid breaker, carcass, and a filler or chafer, incorporating synthetic textile filamentary cords as defined in the preceding paragraph.
  • a cord in accordance with the invention is formed from a polyester, and preferably the polyester is polyethylene terephthalate known as Terylene (registered Trademark). Alternatively the cord may be formed from polypropylene, rayon or nylon.
  • a synthetic textile filamentary cord is made by spinning together 50 monofilaments of polyethylene terephthalate to form a yarn and twisting two of these yarns together to form the cord.
  • the monofilaments are formed by a melt spinning process and a hot drawing process in known manner and have a denier of
  • the cord is then subjected to a hot stretching process during which the cord is raised to a temperature near to the melting point of the constituent monofilaments and simultaneously stretched. This process may take place in a fluid bed such as is described in the specification of British Patent No. 885,513. Fluid beds are very effective in carryice ing out this process since high temperatures can be achieved without degradation of the material. As a result of this process the yarn denier is reduced but the filament denier remains substantially constant.
  • the cords are assembled in the form of a sheet, the cords being interconnected by a very weak weft material and, as is common in the tire-building art, the sheet of cords is treated with adhesive to increase the rubber-tocord bond strength and rubberised on both sides by means of a calender in known manner.
  • a pneumatic tire is constructed from a plurality of layers of these cords utilised in the breaker and/or carcass construction.
  • the cords in the carcass lie at to a circumferential line and the breaker comprises three layers of cords according to the invention, the cords in each of the layers being laid in a dilferent direction to the cords in any of the other layers and to the cords in the carcass.
  • a 90 cord carcass is used and two, four or more, breaker layers are utilised, the cords in one layer crossing those in the next adjacent layer or layers and the cords being disposed at about 18 to the mid-circumferential plane of the tire.
  • a synthetic textile filamentary cord comprising two or more yarns twisted together, each 'of such yarns comprising a plurality of filaments each of which has a denier greater than 10, the cord having been heat-stretched to increase the tensile modulus of the cord and to increase the resistance of the cord to buckling under an axial compression load.
  • a pneumatic tire comprising a carcass of elastomeric material and a reinforcement in said carcass of a synthetic textile filamentary cord comprising two or more yarns twisted together, each of such yarns comprising a plurality of filaments each of which has a denier greater than 10, the cord having been heat-stretched to increase the tensile modulus of the cord and to increase the resistance of the cord to buckling under an axial compression load.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Textile Engineering (AREA)
  • Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
  • Tires In General (AREA)

Description

United States Patent 3,419,060 TEXTILE CORD MATERIAL AND PNEUMATIC TIRES MANUFACTURED THEREWITH Ronald Stansfield Goy, Sutton Coldfield, England, assignor to Dunlop Rubber Company Limited, London, England, a British company No Drawing. Filed Nov. 6, 1964, Ser. No. 409,598 Claims priority, application Great Britain, Nov. 19, 1963, 45,538/63 4 Claims. (Cl. 152-359) ABSTRACT OF THE DISCLOSURE A synthetic hot stretched textile filamentary cord wherein each filament thereof in the finished form of the cord has a denier which is greater than thereby contributing superior resistance to buckling of the cord under axial compression loading.
My invention relates to textile cord material and to pneumatic tires manufactured therewith.
Steel cords made from a plurality of wires twisted together to form strands, the strands being twisted to form a cord, have been used in the manufacture of pneumatic tires for a considerable length of time and they are of advantage particularly in respect of their high tensile modulus (Youngs modulus) and their high resistance to buckling under axial load. Known textile cords are considered inferior to steel cords in these respects and it is an object of the invention to provide a synthetic textile filamentary cord which has an improved performance when compared with existing synthetic textile cords.
In the manufacture of synthetic textile filamentary cords, the filamentary size is usually kept to a minimum in view of the fact that spinning of the filaments is more convenient with a thin filament than with a thick one and, furthermore, the finished yarn is of ifiner texture which is more suitable for most purposes. In addition, while it is 'known to hot stretch nylon cords, to reduce subsequent tire growth, heat treatment is also carried out so as to prevent subsequent shrinkage of the material upon heating during vulcanisation and so as to set the material thus stabilizing its length.
According to my invention a synthetic textile filamentary cord comprises a plurality of filaments or monofilaments, having a denier greater than 10, twisted together, the cord having been heat-stretched to increase the tensile modulus of the cord and to increase the resistance of the cord to buckling under an axial compression load.
According to my invention also, a pneumatic tire comprises a tire building element, e.g. a rigid breaker, carcass, and a filler or chafer, incorporating synthetic textile filamentary cords as defined in the preceding paragraph.
Preferably a cord in accordance with the invention is formed from a polyester, and preferably the polyester is polyethylene terephthalate known as Terylene (registered Trademark). Alternatively the cord may be formed from polypropylene, rayon or nylon.
An embodiment of the invention will now be described by way of example.
A synthetic textile filamentary cord is made by spinning together 50 monofilaments of polyethylene terephthalate to form a yarn and twisting two of these yarns together to form the cord. The monofilaments are formed by a melt spinning process and a hot drawing process in known manner and have a denier of The cord is then subjected to a hot stretching process during which the cord is raised to a temperature near to the melting point of the constituent monofilaments and simultaneously stretched. This process may take place in a fluid bed such as is described in the specification of British Patent No. 885,513. Fluid beds are very effective in carryice ing out this process since high temperatures can be achieved without degradation of the material. As a result of this process the yarn denier is reduced but the filament denier remains substantially constant.
The cords are assembled in the form of a sheet, the cords being interconnected by a very weak weft material and, as is common in the tire-building art, the sheet of cords is treated with adhesive to increase the rubber-tocord bond strength and rubberised on both sides by means of a calender in known manner.
A pneumatic tire is constructed from a plurality of layers of these cords utilised in the breaker and/or carcass construction.
In one pneumatic tire construction, the cords in the carcass lie at to a circumferential line and the breaker comprises three layers of cords according to the invention, the cords in each of the layers being laid in a dilferent direction to the cords in any of the other layers and to the cords in the carcass.
In another pneumatic tire construction a 90 cord carcass is used and two, four or more, breaker layers are utilised, the cords in one layer crossing those in the next adjacent layer or layers and the cords being disposed at about 18 to the mid-circumferential plane of the tire.
It is an advantage to manufacture tires of the kind described above comprising cords according to the invention in view of the fact that the cords have, on the one hand, a high tensile modulus and, on the other hand, a high compressive modulus and increased resistance to buckling under axial compression loads compared with known textile cord material. The resulting tire has improved performance and wear characteristics compared with previously known textile tire constructions.
Having now described my invention, what I claim is:
1. A synthetic textile filamentary cord comprising two or more yarns twisted together, each 'of such yarns comprising a plurality of filaments each of which has a denier greater than 10, the cord having been heat-stretched to increase the tensile modulus of the cord and to increase the resistance of the cord to buckling under an axial compression load.
2. A pneumatic tire comprising a carcass of elastomeric material and a reinforcement in said carcass of a synthetic textile filamentary cord comprising two or more yarns twisted together, each of such yarns comprising a plurality of filaments each of which has a denier greater than 10, the cord having been heat-stretched to increase the tensile modulus of the cord and to increase the resistance of the cord to buckling under an axial compression load.
3. The pneumatic tire of claim 2 in which the cord is formed of a polyester.
4. The pneumatic tire of claim 3 in which the polyester is polyethylene terephthalate.
References Cited UNITED STATES PATENTS 2,273,200 2/1942 Hofi 57140 XR 2,324,583 7/1943 Jackson et al. 57-140 2,755,214 7/1956 Lyons et al. 152359 XR 2,991,817 7/1961 Gay et al l52359 XR 3,051,212 8/1962 Daniels 152330 3,195,603 7/1965 Ahles 152-359 2,235,867 3/1941 Castricum et al. 57140 XR 3,243,338 3/1966 Jackson 152-359 XR FOREIGN PATENTS 512,002 8/1929 Great Britain.
FRANK J. COHEN, Primary Examiner. D. E. WATKINS, Assistant Examiner.
US. Cl. X.R. 5714O
US409598A 1963-11-19 1964-11-06 Textile cord material and pneumatic tires manufactured therewith Expired - Lifetime US3419060A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB45538/63A GB1081089A (en) 1963-11-19 1963-11-19 Improvements in or relating to textile cord material and pneumatic tyres manufacturedtherewith

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US3419060A true US3419060A (en) 1968-12-31

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DE (1) DE1510599A1 (en)
GB (1) GB1081089A (en)
MY (1) MY6900006A (en)

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3638706A (en) * 1968-11-05 1972-02-01 Ici Ltd Macrofilamentary tire yarns
US3690362A (en) * 1970-09-28 1972-09-12 Allied Chem High strength polyethylene terephthalate yarn and cord produced therefrom
DE2161967A1 (en) * 1971-12-14 1973-06-20 Hoechst Ag TIRE WIRE AND METHOD OF MANUFACTURING THIS WIRE
US3849976A (en) * 1966-09-13 1974-11-26 Ici Ltd High modulus tire cord
US3858386A (en) * 1971-07-06 1975-01-07 Fiber Industries Inc Polyester yarn production
US3889457A (en) * 1968-10-11 1975-06-17 Ici Ltd Macrofilamentary yarns
US4043985A (en) * 1971-12-14 1977-08-23 Hoechst Aktiengesellschaft Tire monofilaments
US4328850A (en) * 1978-08-07 1982-05-11 The Toyo Rubber Industry Co., Ltd. Radial tire for truck and bus having specified tread to tire width ratio
US4715176A (en) * 1985-06-03 1987-12-29 Mitsuboshi Belting Ltd. Power transmission tensile cord and belt manufacture
US5442903A (en) * 1991-02-21 1995-08-22 Rhone-Poulenc Fibres Thermoset twist composed of synthetic monofilaments
WO2016091812A1 (en) 2014-12-09 2016-06-16 Compagnie Generale Des Etablissements Michelin High modulus textile cord with an at least triple twist
WO2016091811A1 (en) 2014-12-09 2016-06-16 Compagnie Generale Des Etablissements Michelin Aramid textile cord with an at least triple twist
WO2016091810A1 (en) 2014-12-09 2016-06-16 Compagnie Generale Des Etablissements Michelin Cellulose textile cord having an at least triple twist
WO2016156263A1 (en) 2015-03-31 2016-10-06 Compagnie Generale Des Etablissements Michelin Hybrid reinforcing element with differential twist
WO2018202982A1 (en) 2017-05-05 2018-11-08 Compagnie Generale Des Etablissements Michelin Tyre for vehicle
WO2018202980A1 (en) 2017-05-05 2018-11-08 Compagnie Generale Des Etablissements Michelin Tyre for a vehicle
WO2018202983A1 (en) 2017-05-05 2018-11-08 Compagnie Generale Des Etablissements Michelin Tyre for a vehicle
WO2018202981A1 (en) 2017-05-05 2018-11-08 Compagnie Generale Des Etablissements Michelin Vehicle tyre
WO2019180367A1 (en) 2018-03-20 2019-09-26 Compagnie Generale Des Etablissements Michelin Pneumatic tyre comprising an improved aramid textile cord with an at least triple twist
WO2019180369A1 (en) 2018-03-20 2019-09-26 Compagnie Generale Des Etablissements Michelin Improved aramid textile cord with an at least triple twist
WO2023088848A1 (en) 2021-11-19 2023-05-25 Compagnie Generale Des Etablissements Michelin Tyre comprising a pair of flexible bead cores

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB512002A (en) * 1937-07-22 1939-08-28 American Viscose Corp Improvements in and relating to the production of rayon yarn
US2235867A (en) * 1939-12-07 1941-03-25 Us Rubber Co Pneumatic tire
US2273200A (en) * 1938-11-01 1942-02-17 Du Pont Artificial structure
US2324583A (en) * 1940-06-10 1943-07-20 Celanese Corp Cord for use in the covers of pneumatic tires and other reinforced articles of rubber and similar materials
US2755214A (en) * 1952-07-18 1956-07-17 Firestone Tire & Rubber Co Tire cord and method of making same
US2991817A (en) * 1957-09-04 1961-07-11 Firestone Tire & Rubber Co Pneumatic tire construction
US3051212A (en) * 1959-06-26 1962-08-28 Du Pont Reinforced composite structures
US3195603A (en) * 1964-04-14 1965-07-20 Du Pont Pneumatic tire and process of manufacture
US3243338A (en) * 1960-07-27 1966-03-29 Dunlop Tire & Rubber Corp Flexible elastomeric articles and reinforcement therefor

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB512002A (en) * 1937-07-22 1939-08-28 American Viscose Corp Improvements in and relating to the production of rayon yarn
US2273200A (en) * 1938-11-01 1942-02-17 Du Pont Artificial structure
US2235867A (en) * 1939-12-07 1941-03-25 Us Rubber Co Pneumatic tire
US2324583A (en) * 1940-06-10 1943-07-20 Celanese Corp Cord for use in the covers of pneumatic tires and other reinforced articles of rubber and similar materials
US2755214A (en) * 1952-07-18 1956-07-17 Firestone Tire & Rubber Co Tire cord and method of making same
US2991817A (en) * 1957-09-04 1961-07-11 Firestone Tire & Rubber Co Pneumatic tire construction
US3051212A (en) * 1959-06-26 1962-08-28 Du Pont Reinforced composite structures
US3243338A (en) * 1960-07-27 1966-03-29 Dunlop Tire & Rubber Corp Flexible elastomeric articles and reinforcement therefor
US3195603A (en) * 1964-04-14 1965-07-20 Du Pont Pneumatic tire and process of manufacture

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3849976A (en) * 1966-09-13 1974-11-26 Ici Ltd High modulus tire cord
US3889457A (en) * 1968-10-11 1975-06-17 Ici Ltd Macrofilamentary yarns
US3638706A (en) * 1968-11-05 1972-02-01 Ici Ltd Macrofilamentary tire yarns
US3690362A (en) * 1970-09-28 1972-09-12 Allied Chem High strength polyethylene terephthalate yarn and cord produced therefrom
US3858386A (en) * 1971-07-06 1975-01-07 Fiber Industries Inc Polyester yarn production
DE2161967A1 (en) * 1971-12-14 1973-06-20 Hoechst Ag TIRE WIRE AND METHOD OF MANUFACTURING THIS WIRE
US4043985A (en) * 1971-12-14 1977-08-23 Hoechst Aktiengesellschaft Tire monofilaments
US4328850A (en) * 1978-08-07 1982-05-11 The Toyo Rubber Industry Co., Ltd. Radial tire for truck and bus having specified tread to tire width ratio
US4715176A (en) * 1985-06-03 1987-12-29 Mitsuboshi Belting Ltd. Power transmission tensile cord and belt manufacture
US5442903A (en) * 1991-02-21 1995-08-22 Rhone-Poulenc Fibres Thermoset twist composed of synthetic monofilaments
WO2016091810A1 (en) 2014-12-09 2016-06-16 Compagnie Generale Des Etablissements Michelin Cellulose textile cord having an at least triple twist
US10689780B2 (en) 2014-12-09 2020-06-23 Compagnie Generale Des Etablissements Michelin High modulus textile cord with an at least triple twist
WO2016091812A1 (en) 2014-12-09 2016-06-16 Compagnie Generale Des Etablissements Michelin High modulus textile cord with an at least triple twist
WO2016091811A1 (en) 2014-12-09 2016-06-16 Compagnie Generale Des Etablissements Michelin Aramid textile cord with an at least triple twist
WO2016156263A1 (en) 2015-03-31 2016-10-06 Compagnie Generale Des Etablissements Michelin Hybrid reinforcing element with differential twist
US10688828B2 (en) 2015-03-31 2020-06-23 Compagnie Generale Des Etablissments Michelin Hybrid reinforcing element with differential twist
WO2018202982A1 (en) 2017-05-05 2018-11-08 Compagnie Generale Des Etablissements Michelin Tyre for vehicle
WO2018202981A1 (en) 2017-05-05 2018-11-08 Compagnie Generale Des Etablissements Michelin Vehicle tyre
WO2018202983A1 (en) 2017-05-05 2018-11-08 Compagnie Generale Des Etablissements Michelin Tyre for a vehicle
WO2018202980A1 (en) 2017-05-05 2018-11-08 Compagnie Generale Des Etablissements Michelin Tyre for a vehicle
WO2019180367A1 (en) 2018-03-20 2019-09-26 Compagnie Generale Des Etablissements Michelin Pneumatic tyre comprising an improved aramid textile cord with an at least triple twist
WO2019180369A1 (en) 2018-03-20 2019-09-26 Compagnie Generale Des Etablissements Michelin Improved aramid textile cord with an at least triple twist
WO2023088848A1 (en) 2021-11-19 2023-05-25 Compagnie Generale Des Etablissements Michelin Tyre comprising a pair of flexible bead cores
FR3129322A1 (en) 2021-11-19 2023-05-26 Compagnie Generale Des Etablissements Michelin Pneumatic comprising a pair of flexible rods

Also Published As

Publication number Publication date
DE1510599A1 (en) 1970-02-05
MY6900006A (en) 1969-12-31
GB1081089A (en) 1967-08-31

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