PNEUMATIC TIRE
A pneumatic tire has a rubber hardness higher than a rubber hardness of a rim cushion rubber, and includes a reinforced rubber between a turned back portion of a carcass layer and a sidewall rubber and between the turned back portion and the rim cushion rubber. A height H 1 of a bead filler based on a measuring point of a rim diameter has a relationship of 0.10≤H 1/ SH≤0.23 with respect to a tire cross-sectional height SH. A height H 2 of the reinforced rubber based on the measuring point of the rim diameter has a relationship of 0.40≤H 2/ SH≤0.55 with respect to the tire cross-sectional height SH. A cross-sectional area S 2 of the reinforced rubber in a cross-sectional view in a tire meridian direction has a relationship of 1.10≤S 2/ S 1≤ 2.70 with respect to a cross-sectional area S 1 of the bead filler.
1 . A pneumatic tire, comprising:
a pair of bead cores;
a pair of bead fillers disposed on an outer side in a radial direction of the pair of bead cores;
a carcass layer wound and turned back toward an outer side in a tire width direction and wrapping the bead cores and the bead fillers;
a pair of cross belts disposed on an outer side in the radial direction of the carcass layer;
a tread rubber;
a sidewall rubber; and,
a rim cushion rubber,
the pneumatic tire comprising a reinforced rubber having a rubber hardness higher than a rubber hardness of the rim cushion rubber, the reinforced rubber being disposed between a turned back portion of the carcass layer and the sidewall rubber and between the turned back portion of the carcass layer and the rim cushion rubber,
a height H 1 of the bead filler based on a measuring point of a rim diameter having a relationship of 0.10≤H 1 /SH≤0.23 with respect to a tire cross-sectional height SH,
a height H 2 of the reinforced rubber based on the measuring point of the rim diameter having a relationship of 0.40≤H 2 /SH≤0.55 with respect to the tire cross-sectional height SH, and,
a cross-sectional area S 2 of the reinforced rubber in a cross-sectional view in a tire meridian direction having a relationship of 1.10≤S 2 /S 1 ≤2.70 with respect to a cross-sectional area S 1 of the bead filler.
2 . The pneumatic tire according to claim 1 , wherein a difference between the height H 2 of the reinforced rubber and the height H 1 of the bead filler has a relationship of 0.17≤(H 2 −H 1 )/SH≤0.45 with respect to the tire cross-sectional height SH.
3 . The pneumatic tire according to claim 1 , wherein an overlap L 1 of the reinforced rubber with respect to the bead filler in a tire radial direction has a relationship of 0.15≤L 1 /L 0 ≤0.65 with respect to a radial length L 0 of the bead filler.
4 . The pneumatic tire according to claim 1 , wherein a difference between a rubber hardness Hs2 of the reinforced rubber and a rubber hardness Hs1 of the bead filler has a relationship of 1≤Hs2−Hs1.
5 . The pneumatic tire according to claim 1 , wherein a rubber hardness Hs2 of the reinforced rubber is within a range of 88≤Hs2≤98.
6 . The pneumatic tire according to claim 1 , wherein a difference between the height H 1 of the bead filler and a rim flange height H 0 of a specified rim has a relationship of 0 mm≤H 1 −H 0 .
7 . The pneumatic tire according to claim 1 , wherein a difference between the height H 2 of the reinforced rubber and a height H 3 of the rim cushion rubber has a relationship of 0.10≤(H 2 −H 3 )/SH≤0.30 with respect to the tire cross-sectional height SH.
8 . The pneumatic tire according to claim 1 , wherein a height H 3 of the rim cushion rubber based on the measurement point of the rim diameter has a relationship of 0.25≤H 3 /SH≤0.35 with respect to the tire cross-sectional height SH.
9 . The pneumatic tire according to claim 1 , wherein an imaginary line X passing through an end point P on an outer side in the radial direction of the bead filler and orthogonal to a tire inner surface is defined, and a thickness T 2 of the reinforced rubber and a thickness T 3 of the rim cushion rubber on the imaginary line X have a relationship of 0.45≤T 2 /(T 2 +T 3 )≤0.70.
10 . The pneumatic tire according to claim 1 , wherein a difference between a rubber hardness Hs2 of the reinforced rubber and a rubber hardness Hs3 of the rim cushion rubber has a relationship of 13≤Hs2−Hs3.
11 . The pneumatic tire according to claim 1 , wherein a height H 4 of the turned back portion of the carcass layer has a relationship of 0.20≤H 4 /SH≤0.65 with respect to the tire cross-sectional height SH.
12 . The pneumatic tire according to claim 1 , wherein a difference between a height H 4 of the turned back portion of the carcass layer and the height H 1 of the bead filler based on the measuring point of the rim diameter has a relationship of 0.10≤(H 4 −H 1 )/SH with respect to the tire cross-sectional height SH.
13 . The pneumatic tire according to claim 1 , wherein a belt width Wb of the cross belt that is wider has a relationship of 1.10≤Wb/SH≤1.60 with respect to the tire cross-sectional height SH.
14 . The pneumatic tire according to claim 1 , wherein a belt width Wb of the cross belt that is wider has a relationship of 0.75≤Wb/SW≤0.95 with respect to a total tire width SW.
15 . The pneumatic tire according to claim 1 , wherein the pneumatic tire is a radial tire for a passenger vehicle having an aspect ratio of 60% or higher.