Tire

Abstract

The present invention provides a tire in which wet performance can be improved without sacrificing steering stability. A tire (1) has designated installation direction on a vehicle. An outboard shoulder land region (8) is provided with outboard shoulder sipes (26). The outboard shoulder sipe (26) comprises a deep bottom part (27) and a shallow bottom part (28) with a depth smaller than the deep bottom part (27). The shallow bottom part (28) comprises a first part (30) extending axially inwardly from the axially inner end (27i) of the deep bottom part (27) towards a tire equator C, a second part (31) extending axially outwardly from the outboard shoulder main groove (4) to wards an outboard tread edge (To), and a third part (32) connecting the first part (30) and the second part (31). The first part (30), the second part (31) and the third part (32) have different angles with respect to the tire axial direction.

Description

technical field

[0001] The present invention relates to a tire that maintains handling stability and improves wet performance. Background technique

[0002] Conventionally, there is known a tire provided with sipes in a tread portion. Such a tire exhibits high wet grip on a wet road surface due to, for example, the frictional force and wiping effect brought about by the edges of the sipes, so that wet performance can be improved.

[0003] In order to further improve wetland performance, consider increasing the number of sipes. However, in such tires, the rigidity of the land contact portion of the tread portion is lowered, so there is a problem that the steering stability performance tends to deteriorate.

[0004] prior art literature

[0005] patent documents

[0006] Patent Document 1: Japanese Patent Laid-Open No. 2016-13820 Contents of the invention

[0007] The problem to be solved by the invention

[0008] The present invention has been made in view of the abov...

Examples

Embodiment

[0086] Trial production according to the specifications in Table 1 has figure 1 The size of the basic pattern is 195 / 65R15 tires, and the drainage performance and handling stability of each trial tire are tested. Common specifications and test methods for each trial tire are as follows. The second portion, the first portion, and the third portion of the outer shoulder sipe are inclined in opposite directions with respect to the tire axial direction.

[0087] Groove depth of inner shoulder main groove and outer shoulder main groove: 6.2mm

[0088] Groove depth of crown main groove: 6.3mm

[0089] Depth D2 of the deep bottom of the second inner shoulder sipe: 3.6mm

[0090] Depth D3 of the shallow bottom of the second inner shoulder sipe: 1 mm

[0091] Depth D8 of deep bottom of outer shoulder sipe: 3.6mm

[0092]

[0093] Each test tire was mounted on all wheels of a rear-wheel drive passenger car under the following conditions. Then, the test driver drives on a test co...

technical field

[0001] The present invention relates to a tire that maintains handling stability and improves wet performance. Background technique

[0002] Conventionally, there is known a tire provided with sipes in a tread portion. Such a tire exhibits high wet grip on a wet road surface due to, for example, the frictional force and wiping effect brought about by the edges of the sipes, so that wet performance can be improved.

[0003] In order to further improve wetland performance, consider increasing the number of sipes. However, in such tires, the rigidity of the land contact portion of the tread portion is lowered, so there is a problem that the steering stability performance tends to deteriorate.

[0004] prior art literature

[0005] patent documents

[0006] Patent Document 1: Japanese Patent Laid-Open No. 2016-13820 Contents of the invention

[0007] The problem to be solved by the invention

[0008] The present invention has been made in view of the abov...

Examples

Embodiment

[0086] Trial production according to the specifications in Table 1 has figure 1 The size of the basic pattern is 195 / 65R15 tires, and the drainage performance and handling stability of each trial tire are tested. Common specifications and test methods for each trial tire are as follows. The second portion, the first portion, and the third portion of the outer shoulder sipe are inclined in opposite directions with respect to the tire axial direction.

[0087] Groove depth of inner shoulder main groove and outer shoulder main groove: 6.2mm

[0088] Groove depth of crown main groove: 6.3mm

[0089] Depth D2 of the deep bottom of the second inner shoulder sipe: 3.6mm

[0090] Depth D3 of the shallow bottom of the second inner shoulder sipe: 1 mm

[0091] Depth D8 of deep bottom of outer shoulder sipe: 3.6mm

[0092]

[0093] Each test tire was mounted on all wheels of a rear-wheel drive passenger car under the following conditions. Then, the test driver drives on a test co...

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