Patent US4718470A successfully refreshed from Google Patents.
US4718470A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pneumatic radial tires
Assignee: Bridgestone Corp
•
Filing: 1986-03-07
•
Granted: 1988-01-12
•
Expires: 2006-03-07
Abstract
Abstract A pneumatic radial tire comprising a carcass of a radial structure and a belt superimposed about a crown portion of the carcass is disclosed. The belt is composed of at least one open-twisted steel cord layer formed by embedding open-twisted steel cords. Each cord is composed of 4-5 steel filaments and having an elongation of 0.2-0.7% under a load of 5 kg/cord and a twisting pitch of 8-16 mm, in a coating rubber having a 100% modulus of 30-70 kg/cm2.
Inventors
- 👤 Noboru Kusakabe
- 👤 Masaaki Morimoto
- 👤 Eiichi Koyama
- 👤 Koichi Kojima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 16:53
CPC Classifications
D; D07; D07B; D07B1/00; D07B1/06; D07B1/0606; D07B1/062; B; B60; B60C; B60C9/00; B60C9/0007; B60C9/18; B60C9/20; B60C9/2003; B60C9/2006; D07B2201/00; D07B2201/20; D07B2201/2015; D07B2201/2022; D07B2201/2024; D07B2201/2029; Y; Y10; Y10S; Y10S57/00; Y10S57/902
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
164 words
A passenger car pneumatic radial tire comprising a carcass of radial structure and a belt superimposed about an outer periphery of a crown portion of said carcass and composed of a rubberized steel cord layer, the improvement wherein said belt is composed of at least one open-twisted steel cord layer formed by embedding open-twisted steel cords, each cord being composed of 4 to 5 adjacent steel filaments with an open-twisted construction in the lengthwise direction of the cord, said open-twisted construction having alternatively an open-twisted portion in which all of steel filaments are twisted without being closed to each other and a relatively closely twisted portion wherein at least two, but not all, of the adjacent filaments are substantially closed with each other and, said cord having an elongation of 0.2 to 0.7 percent under a load of 5 kg/cord and a twisting pitch of 8 to 16 mm, in a coating rubber having a 100% modulus of 30 to 70 kg/cm 2 .
Claim 2
Dependent Claim
164 words
A passenger car pneumatic radial tire comprising a carcass of radial structure and a belt superimposed about an outer periphery of a crown portion of said carcass and composed of a rubberized steel cord layer, the improvement wherein said belt is composed of at least one open-twisted steel cord layer formed by embedding open-twisted steel cords, each cord being composed of 4 to 5 adjacent steel filaments with an open-twisted construction in the lengthwise direction of the cord, said open-twisted construction having alternatively an open-twisted portion in which all of steel filaments are twisted without being closed to each other and a relatively closely twisted portion wherein at least two, but not all, of the adjacent filaments are substantially closed with each other and, said cord having an elongation of 0.2 to 0.7 percent under a load of 5 kg/cord and a twisting pitch of 8 to 16 mm, in a coating rubber having a 100% modulus of 30 to 70 kg/cm 2 .
Claim 3
Dependent Claim
31 words
The pneumatic radial tire according to claim 1, wherein said open twisted portion and relatively closely twisted portion have an open space to make it possible to penetrate a coating rubber.
Claim 4
Dependent Claim
21 words
The pneumatic radial tire according to claim 1, wherein said coating rubber has a 100% modulus of 35-55 kg/cm 2 .
Claim 5
Dependent Claim
20 words
The pneumatic radial tire according to claim 1, wherein said steel filament has a diameter of 0.12 to 0.4 mm.
Claim 6
Dependent Claim
85 words
An open-twisted steel cord comprising; 4 to 5 adjacent steel filaments with an open-twisted construction in the lengthwise direction of the cord, said open-twisted construction having alternatively an open-twisted portion in which all of the steel filaments are twisted without being closed to each other and a relatively closely twisted portion wherein at least two, but not all, of the adjacent filaments are substantially closed with each other and, said cord having an elongation of 0.2 to 0.7 percent under a load of 5 kg/cord.
Claim 7
Dependent Claim
85 words
An open-twisted steel cord comprising; 4 to 5 adjacent steel filaments with an open-twisted construction in the lengthwise direction of the cord, said open-twisted construction having alternatively an open-twisted portion in which all of the steel filaments are twisted without being closed to each other and a relatively closely twisted portion wherein at least two, but not all, of the adjacent filaments are substantially closed with each other and, said cord having an elongation of 0.2 to 0.7 percent under a load of 5 kg/cord.
Claim 8
Dependent Claim
31 words
The open-twisted steel cord according to claim 5, wherein said open twisted portion and relatively closely twisted portion have an open space to make it possible to penetrate a coating rubber.
Claim 9
Dependent Claim
20 words
The open-twisted steel cord according to claim 5, wherein said steel filament has a diameter of 0.12 to 0.4 mm.
Claim 10
Dependent Claim
20 words
The open-twisted steel cord according to claim 5, wherein a twisting pitch of said cord is 8 to 16 mm.
Claim 11
Dependent Claim
17 words
The open-twisted steel cord according to claim 5, wherein said cord is a 1×4 or 1×5 construction.
References Cited (Backward Citations)
US2492352A
Cited
US3090189A
Cited
US3273978A
Cited
US3682222A
Cited
US4047552A
Cited
US4161203A
Cited
US4258543A
Cited
US4333306A
Cited
JPS56163905A
Cited
US4399853A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-01-11 | 1991-07-13 | 1992-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-01-11 | 1995-07-13 | 1996-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-01-11 | 1999-07-13 | 2000-01-12 | $7700.00 | Window Closed / Lapsed |