Pneumatic tire

Patent metadata

Field	Value
Publication number	US-9962998-B2
Application number	US-201414912203-A
Country	US
Kind code	B2
Filing date	Aug 7, 2014
Priority date	Aug 23, 2013
Publication date	May 8, 2018
Grant date	May 8, 2018

Abstract

A pneumatic tire includes a recess formed on a groove wall surface of a circumferential groove opposite to a widthwise groove. A wall surface defined by the recess includes an inclined surface inclined towards the widthwise groove from a tire radial direction outer side towards a tire radial direction inner side and a curved surface connecting a tire radial direction inner end of the inclined surface to a bottom defined by the recess, the curved surface having a center of curvature on the side of the widthwise groove. As a connection point between the inclined surface and the curved surface is at a position in the tire circumferential direction at which a width W of the recess in the tire width direction is smaller, the connection point is located further inward in the tire radial direction.

First claim

The invention claimed is:

1. A pneumatic tire comprising, in a tread surface, at least one circumferential groove extending along a tire circumferential direction and a plurality of widthwise grooves opening to the circumferential groove, the widthwise grooves having a groove width wider than a groove width of the circumferential groove at least in a portion opening to the circumferential groove, and the widthwise grooves extending in a direction inclined with respect to the tire circumferential direction, wherein
a recess is formed on a groove wall surface of the circumferential groove opposite to the widthwise groove,
the recess has a width W measured from a connection point between the recess and the circumferential groove in a tire width direction,
a wall surface defined by the recess includes an inclined surface inclined towards the widthwise groove from a tire radial direction outer side towards a tire radial direction inner side and a curved surface connecting a tire radial direction inner end of the inclined surface to a bottom defined by the recess, the curved surface having a center of curvature on the side of the widthwise groove,
a connection point between the inclined surface and the curved surface has a height h expressed in mm in the tire radial direction,
the height h of the connection point gradually decreases towards the widthwise groove from a position at which the recess has the largest width, and
the widthwise grooves communicate between the circumferential groove and a tread edge.

2. The pneumatic tire of claim 1 , wherein
0.11 W+ 3.94≤ h≤ 0.33 W+ 22.3

in mm.

3. The pneumatic tire of claim 1 , wherein
0< h≤H/ 2
where H is a height in mm of a land portion defined by the recess.

4. The pneumatic tire of claim 1 , wherein in a standard state in which the tire is mounted on an applicable rim, a prescribed internal pressure is applied, and no load is applied, an inclination angle of the inclined surface with respect to the tire radial direction is greater than 0° and less than 30°.

5. The pneumatic tire of claim 1 , wherein in the standard state, a radius of curvature of the curved surface in the recess is constant.

6. The pneumatic tire of claim 1 , wherein a line connecting two end points of the curved surface where the curved surface meets the circumferential groove lies along the tire circumferential direction.

7. The pneumatic tire of claim 1 , wherein the recess has a triangular planar shape when viewed from the tread surface.

8. The pneumatic tire of claim 1 , wherein
0.0025 TW≤Wc 2≤0.025 TW

where TW is a tread width between ground contact edges when the tire is mounted on an applicable rim, a prescribed internal pressure is applied, and a maximum load is applied, and Wc 2 is the groove width of the circumferential groove.

Assignees

• Bridgestone Corp

Inventors

• Ogane Shun

Classifications

• B60C2011/0381

  Blind or isolated grooves · CPC title

• B60C2011/0353

  characterised by width · CPC title

• B60C2011/133

  comprising recesses · CPC title

• B60C2011/0355

  characterised by depth · CPC title

• B60C11/0327

  characterised by special properties of the tread pattern · CPC title