Radial tire with even wear at tread shoulders
AssigneeSumitomo Rubber Industries, Ltd.
InventorsKenji Saito, Akira Kajikawa, Akihiro Nakatani, Atsushi Yamahira, Hiroyuki Noma, Kazuhiko Kawamura
Life of this patent
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Abstract
A belted radial ply tire which comprises a bead core disposed in each bead portion, a carcass extending between the bead portions and turned up around the bead cores, and a belt comprising at least two cross plies disposed radially outside the carcass and inside the tread, and in a state that the tire is mounted on its regular rim and inflated to its regular inner pressure but loaded with no tire load, the effective belt width BW of the effective belt part BE of the belt, the belt edge camber height CH of the belt, and the tire section width TW satisfy 2.50(BW/TW)-1.25<CH<13.3(BW/TW)-4.65.
Claims12
A belted radial ply tire comprising
- a tread
- a bead core disposed in each of a pair of bead portions,
- a carcass extending between the pair of bead portions and turned up around each of the bead cores, and
- a belt comprising at least two cross plies disposed radially outside the carcass and inside the tread,
- in a normal state that the tire is mounted on its regular rim and inflated to its regular inner pressure but loaded with no tire load,
- a belt profile comprising a central part IP and a pair of lateral parts OP, wherein,
- said belt profile is defined by a thickness center curve L drawn radially equidistantly from the centers of the cords which compose each of two plies forming the effective belt part BE, the effective belt part BE being the part of the belt where the two widest plies overlap such that the cord directions of the respective plies cross each other,
- said central part IP extends between two points B, one located on each side of the tire equatorial plane and spaced apart a distance of 0.3 times the effective belt width BW from the tire equatorial plane, the effective belt width BW in millimeters being the maximum width of the effective belt part BE measured between the axially outermost edge points A thereof,
- said central part IP having a single radius CR1 of curvature being more than 1.4 times and not more than 15 times the tire section width TW in millimeters,
- each said lateral part OP extending axially outwardly from one of the points B to the adjacent outermost edge point A and having a curvature smoothly connected to the curvature of said central part IP, and
- the axially outer edge of each said lateral part OP cambered radially inwardly of the tire, so that said effective belt width BW, said tire section width TW and the belt edge camber height CH in millimeters defined as the radial distance between each of said points A and corresponding points B satisfy the following equation:
- 2.50(BW/TW)-1.25<CH<13.3(BW/TW)-4.65.
A belted radial ply tire comprising
- a tread,
- a bead core disposed in each of a pair of bead portions,
- a carcass extending between the pair of bead portions and turned up around each of the bead cores, and
- a belt comprising at least two cross plies disposed radially outside the carcass and inside the tread,
- in a state that the tire is mounted on its regular rim and inflated to its regular inner pressure but loaded with no tire load,
- the effective belt width BW in millimeters of the effective belt part BE of the belt,
- the belt edge camber height CH in millimeters of the belt, and
- the tire section width TW in millimeters
- satisfying the following equation:
- 2.50(BW/TW)-1.25<CH<13.3(BW/TW)-4.65
- wherein
- the effective belt width BW is the maximum width of the effective belt part BE measured between the axially outermost edge points A thereof,
- the effective belt part BE is the part of the belt where the two widest belt plies overlap such that the cord directions of the respective plies cross each other, and
- the belt edge camber height CH is the radial distance between each of the outermost edge points A of the effective belt part BE and two corresponding points B one of which is located axially inward of each of the outermost edge points A by an axial distance of 0.2 times the effective belt width BW.
Dependencies are inferred from the claim text.