Pneumatic tire

Abstract

Provided is a pneumatic tire in which noise performance is improved by dispersing a pitch noise. At least one of a plurality of land portions (1~5) is formed of a rib on which a plurality of sipes (20) are provided at intervals in the tire circumferential direction, the plurality of sipes (20) include plural types of sipes (21, 22) different in length of a tire width direction, and each of the sipes includes a shoulder-side end portion and a center-side end portion, and when, with regard to each sipe in which the shoulder-side end portion is located closest to a center side among the pluralityof sipes (20), a position of the shoulder-side end portion of the sipe in the tire width direction is taken as a first reference position, and with regard to each sipe in which the center-side end portion is located closest to a shoulder side among the plurality of sipes (20), a position of the center-side end portion of the sipe in the tire width direction is taken as a second reference position, at one of the first reference position and the second reference position, the plurality of sipes (20) are arranged at regular intervals in the tire circumferential direction, and at other of the first reference position and the second reference position, the plurality of sipes (20) are arranged at irregular intervals in the tire circumferential directio.

Description

technical field [0001] The present invention relates to a pneumatic tire including a tread portion. Background technique [0002] In some conventional pneumatic tires, a plurality of cut grooves called sipes are formed on ribs divided by main grooves extending in the tire circumferential direction. By forming many sipes on the rib, it is possible to improve the edge effect, the water removal effect, and improve the running performance on icy and snowy roads, slippery roads, and the like. For example, Patent Documents 1 to 3 described below describe a pneumatic tire having ribs in which a plurality of sipes are arranged at regular intervals in the tire circumferential direction. [0003] However, when sipes are arranged at regular intervals along the tire circumferential direction on the ribs divided by the main grooves, false blocks (hereinafter referred to as "false blocks") will be formed in the region sandwiched between the main grooves and the sipe. Since the sizes and...

AI Technical Summary

Problems solved by technology

[0003] However, when sipes are arranged at regular intervals along the tire circumferential direction on the ribs divided by the main grooves, false blocks (hereinafter referred to as "false blocks") will be formed in the region sandwiched between the main grooves and the sipe. tire blocks"), since the sizes and shapes of the fake tire blocks are the same as each other, there is a problem that the high-frequency impact sound called pitch noise when the fake tire blocks touch the ground becomes louder.

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