US 12,434,510 B2
Pneumatic radial tire for passenger vehicles
Isao Kuwayama, Tokyo (JP); and Shintaro Hatanaka, Tokyo (JP)
Assigned to BRIDGESTONE CORPORATION, Tokyo (JP)
Appl. No. 18/708,207
Filed by BRIDGESTONE CORPORATION, Tokyo (JP)
PCT Filed Jun. 23, 2022, PCT No. PCT/JP2022/025173
§ 371(c)(1), (2) Date May 8, 2024,
PCT Pub. No. WO2023/105830, PCT Pub. Date Jun. 15, 2023.
Claims priority of application No. 2021-201244 (JP), filed on Dec. 10, 2021.
Prior Publication US 2025/0187378 A1, Jun. 12, 2025
Int. Cl. B60C 3/04 (2006.01); B60C 11/00 (2006.01); B60C 11/03 (2006.01); B60C 11/12 (2006.01)
CPC B60C 11/0332 (2013.01) [B60C 3/04 (2013.01); B60C 11/1204 (2013.01); B60C 2011/1209 (2013.01); B60C 2200/04 (2013.01)] 3 Claims
OG exemplary drawing
 
1. A pneumatic radial tire for passenger vehicles, comprising a tread, wherein
sectional width SW of the tire is less than 165 mm,
a ratio SW/OD of the sectional width SW to outer diameter OD of the tire is 0.26 or less, or the sectional width SW (mm) and the outer diameter OD (mm) of the tire satisfy the relational equation
OD(mm)≥−0.0187×SW(mm)2+9.15×SW(mm)−380(mm),
in a tire width direction cross-section, under reference conditions where the tire is mounted on a rim, filled with a prescribed internal pressure, and unloaded, when a straight line passing through a point on a tread surface on a tire equatorial plane and parallel to a tire width direction is m1, a straight line passing through ground contact edges E and parallel to the tire width direction is m2, a distance between the straight line m1 and the straight line m2 in a tire radial direction is a drop height LCR, and a tread width of the tire is TW, a ratio LCR/TW is greater than 0.045,
a contact surface of the tread has only two circumferential main grooves extending in a tire circumferential direction,
a barycenter of the two circumferential main grooves is positioned in a half portion of the tire on a vehicle-mounted outward side, which is one side of the tire in a tread width direction with the tire equatorial plane as a boundary, and
one or more width direction sipes extending in the tread width direction or at an angle of 45° or less to the tread width direction, and/or one or more hole-shaped sipes having a diameter of 2 mm or less, are provided only to a land portion on a vehicle-mounted inward side that is demarcated by one of the circumferential main grooves and a tread edge.