Pneumatic tire

Abstract

The present invention provides a pneumatic tire which has advantages in operation stability and non-uniform wearing resistance on an icy road and a dry road. A pattern block (5) is separately provided with a plurality of sipings (7) along a circumferential direction of the tire. The sipings extend along a direction of transversely cutting the pattern block (5) in the axial direction of the tire. The sipings (7) comprise the following components: hollow and narrow sipings (10) which respectively have a width that is larger than 0.1mm and is smaller than 0.3mm and have a depth that is 0.5-0.6 times of a maximal depth of the transverse grooves; deep and thick sipings (11) which respectively have a width that is larger than 0.3mm and is smaller than 1.0mm and have a depth that is larger than that of the hollow and narrow sipings (10). The hollow and narrow sipings (10) and the deep and thick sipings (11) are alternately formed along a circumferential direction of the tire. Furthermore two ends of each hollow and narrow siping (10) are opened at two side surfaces of the pattern block (5).

Description

technical field [0001] The present invention relates to a pneumatic tire capable of achieving a high balance between handling stability on icy roads and dry roads, uneven wear resistance, and the like. Background technique [0002] A tire suitable for winter use including a studless tire has a block pattern divided into a plurality of blocks on its tread portion. In addition, in order to obtain a sufficient driving force on an icy road surface, sipes are provided on the above-mentioned blocks at intervals in the tire circumferential direction, and the sipes extend in a direction transverse to the above-mentioned block. [0003] Conventionally, various proposals have been made regarding the sipes. For example, Patent Document 1 below describes a three-dimensionally curved sipe using a so-called miura folding method in order to improve running performance on icy roads. Such a sipe is such that even when a shear force acts on the block, the sipe surfaces are firmly engaged wi...

AI Technical Summary

Problems solved by technology

[0006] However, when the thickness of the blade is reduced, the blade is deformed due to the force from the tire side during vulcanization, so vulcanization failure may occur

Also, when the thickness of the blade is reduced in consideration of the durability and rigidity of the blade, the height in the radial direction of the tire cannot be sufficiently increased, and the depth of the sipe has to be reduced in the end.

Such sipes significantly reduce performance on ice due to wear, and when driving on dry roads, there is a tendency for uneven wear to occur because the blocks cannot deform softly

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