Pneumatic tire
AssigneeThe Yokohama Rubber Co., Ltd.
InventorKoji Nishio
Life of this patent
Estimating the term…
Abstract
In a pneumatic tire, a bead filler is radially outward of a bead core, a carcass turned up end is radially inward of an outer side end of the bead filler, the turned up end is spaced from a carcass body, a reinforcement layer is laterally outward of the bead filler, a sidewall rubber extends from a sidewall to the bead, an inner rubber reinforcing layer is between the bead filler and the reinforcement layer and adjacent to the turned up end, a crack suppression layer is between the reinforcement layer and the sidewall rubber, the crack suppression layer extends 5 mm or more from where the crack suppression layer overlaps, the reinforcement layer contacts the carcass body radially outwardly of the bead filler, and a 100% modulus KcM100 of the crack suppression layer is at least 1.5 times that of the sidewall rubber.
Claims14
A pneumatic tire, comprising:
- a tread portion extending in a tire circumferential direction and having an annular shape;
- a pair of sidewall portions respectively disposed on both sides of the tread portion;
- a pair of bead portions each disposed on an inner side in a tire radial direction of the sidewall portions;
- and
- a carcass layer mounted between the pair of bead portions and comprising a plurality of steel cords, the carcass layer being turned up around a bead core of each of the bead portions from a tire inner side to a tire outer side,
- a bead filler being disposed on an outer circumference of the bead core of each of the bead portions, a turned up end portion of the carcass layer being disposed on a radially inner side with respect to a radially outer side end portion of the bead filler, the turned up end portion of the carcass layer being spaced apart from a body portion of the carcass layer, at least one organic fiber reinforced layer that comprises a plurality of organic fiber cords being disposed on an outer side in a width direction of the bead filler in each of the bead portions, and a sidewall rubber layer exposed on a tire outer surface being disposed from the sidewall portion to the bead portion, and
- an inner rubber reinforcing layer being disposed between the bead filler and the organic fiber reinforced layer and adjacent to the turned up end portion of the carcass layer, a crack suppression layer being disposed between the organic fiber reinforced layer and the sidewall rubber layer, the crack suppression layer extending toward a radially outer side from a position where the crack suppression layer overlaps, by 5 mm or more, the organic fiber reinforced layer located on an outermost side in the tire width direction and contacting the body portion of the carcass layer at a position on a radially outer side with respect to the radially outer side end portion of the bead filler, and a 100% modulus KcM100 of the crack suppression layer being at least 1.5 times as large as a 100% modulus SM100 of the sidewall rubber layer, wherein
- the inner rubber reinforcing layer contacts the body portion of the carcass layer at a position on the radially outer side with respect to the radially outer side end portion of the bead filler, the inner rubber reinforcing layer has a 100% modulus KiM100 of from 4.5 MPa to 10.0 MPa, and the inner rubber reinforcing layer has an elongation at break KiEB of 300% or more.
Dependencies are inferred from the claim text.