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US4161203A Expired / Lapsed US ⏱️ 0.0 years remaining

Pneumatic radial tire

Assignee: Bridgestone Corp
•
Filing: 1977-04-26
•
Granted: 1979-07-17
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Expires: 1997-04-26
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Abstract

Abstract A pneumatic radial tire comprising a carcass, and a belt interposed between a tread and the carcass composed of at least two main cord layers whose cords are formed of an inextensible material such as a steel cord is disclosed. The tire further comprises at least one rubberized reinforcing layer interposed between the belt and the carcass and containing reinforcing elements. The reinforcing element is formed of a helically formed filament or a bundle of a plurality of helically formed filaments. The filament has a tensile breaking strength of at least 140 kg/mm 2 and elongation at tensile breaking strength which is at least 1.2 times the smallest elongation at tensile breaking strength of the main cord layers of the belt. The rubberized reinforcing layer as a whole is extensible and compressible.

Inventors

  • 👤 Yasuo Suzuki
  • 👤 Masaru Abe
  • 👤 Toshiro Tezuka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 00:11
CPC Classifications
B; B60; B60C; B60C9/00; B60C9/18; B60C9/28; B60C9/20; B60C9/2003; B60C9/2009; Y; Y10; Y10T; Y10T152/00; Y10T152/10; Y10T152/10495; Y10T152/10765; Y10T152/10792; Y10T152/10801; Y10T152/1081

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 175 words
In a pneumatic radial tire comprising a carcass composed of cords arranged substantially parallel with a vertical center section through the rotational axis of the tire and a belt interposed between a tread and said carcass and composed of at least two main cord layers whose cords are formed of an inextensible material such as a steel cord and arranged along different directions crossed at a small angle with respect to the circumferential direction of the tire, the improvement comprising at least one rubberized reinforcing layer interposed between said belt and said carcass and containing reinforcing elements spaced apart from each other and embedded therein, said reinforcing element being formed of at least a helically formed filament, said helically formed filament being formed of material having a tensile breaking strength of at least 140 kg/mm 2 and elongation at tensile breaking strength which is at least 1.2 times the smallest elongation at tensile breaking strength of said main cord layers of said belt, and said rubberized reinforcing layer as a whole being extensible and compressible.
Claim 2
Dependent Claim 175 words
In a pneumatic radial tire comprising a carcass composed of cords arranged substantially parallel with a vertical center section through the rotational axis of the tire and a belt interposed between a tread and said carcass and composed of at least two main cord layers whose cords are formed of an inextensible material such as a steel cord and arranged along different directions crossed at a small angle with respect to the circumferential direction of the tire, the improvement comprising at least one rubberized reinforcing layer interposed between said belt and said carcass and containing reinforcing elements spaced apart from each other and embedded therein, said reinforcing element being formed of at least a helically formed filament, said helically formed filament being formed of material having a tensile breaking strength of at least 140 kg/mm 2 and elongation at tensile breaking strength which is at least 1.2 times the smallest elongation at tensile breaking strength of said main cord layers of said belt, and said rubberized reinforcing layer as a whole being extensible and compressible.
Claim 3
Dependent Claim 55 words
A pneumatic radial tire as claimed in claim 1, wherein said helically formed filament of said reinforcing element has a filament diameter φ of 0.1 to 1.0 mm and average diameter D projected on a plane perpendicular to the axial direction of one pitch of the filament and given by D=(Dmax+Dmin)/2 of 2φ to 20φ.
Claim 4
Dependent Claim 23 words
A pneumatic radial tire as claimed in claim 1, wherein said helically formed filament of said reinforcing element is formed of steel wire.
Claim 5
Dependent Claim 58 words
A pneumatic radial tire as claimed in claim 1, wherein said main cord layer of said belt contains cords inclined at an angle of at most 30° with respect to the circumferential direction of the tire and said reinforcing element is inclined at an angle of 35° to 90° with respect to the circumferential direction of the tire.
Claim 6
Dependent Claim 48 words
A pneumatic radial tire as claimed in claim 1, wherein rubber in which is embedded said reinforcing element has a Shore A hardness of 50° to 85°, 300% modulus of elasticity of 100 to 200 kg/cm 2 and tensile breaking strength of 150 to 250 kg/cm 2 .

References Cited (Backward Citations)

GB851898A Cited
US3543828A Cited
US3345228A Cited
US3242965A Cited
US3449199A Cited
US3392774A Cited
US3667529A Cited
US3682222A Cited
FR2096405A1 Cited
US4077454A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-07-16 1983-01-15 1983-07-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-07-16 1987-01-15 1987-07-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-07-16 1991-01-15 1991-07-17 $7700.00 Window Closed / Lapsed

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