Pneumatic tire
AssigneeSumitomo Rubber Industries, Ltd.
InventorRyo Oba
Life of this patent
Estimating the term…
Abstract
To provide a pneumatic tire which is improved in on-snow performance, while maintaining steering stability on dry road surface. The pneumatic tire is provided in a tread portion 2 with a pair of shoulder main grooves 3, a center main groove 4, shoulder land portions 6, and middle land portions 5. The middle land portions 5 are provided with middle lateral grooves 10 extending from the shoulder main grooves 3 toward the inside in the tire axial direction, while gradually decreasing the angle with respect to tire circumferential direction. The middle lateral groove 10 is provided with a groove bottom sipe 15 opened in the groove bottom.
Claims14
A pneumatic tire comprising a tread portion provided with
- a pair of shoulder main grooves extending continuously in the tire circumferential direction on the outermost tread edge side,
- a center main groove extending continuously in the tire circumferential direction between the shoulder main grooves,
- a shoulder land portion on the outer side in the tire axial direction of each of the shoulder main grooves, and
- a middle land portion between each of the shoulder main grooves and the center main groove,
- wherein the middle land portion is provided with middle lateral grooves each extending from the shoulder main groove toward the inside in the tire axial direction, while decreasing the angle with respect to the tire circumferential direction,
- wherein the middle lateral grooves include first middle lateral grooves extending to the center main groove and second middle lateral grooves terminating in the middle land portion, and the middle lateral grooves are each provided with a groove bottom sipe extending along the middle lateral groove and opened in the groove bottom of the middle lateral groove, and
- wherein the groove bottom sipe has a width of from 0.4 to 1.0 mm and the middle lateral groove has a width of from 1.3 to 3.0 mm and a depth of from 0.6 to 1.5 mm.
A pneumatic tire comprising
- a tread portion provided with a pair of shoulder main grooves extending continuously in the tire circumferential direction on the outermost tread edge side, a center main groove extending continuously in the tire circumferential direction between the shoulder main grooves, a shoulder land portion on the outer side in the tire axial direction of each of the shoulder main grooves, and a middle land portion between each of the shoulder main grooves and the center main groove,
- wherein said middle land portion is provided with middle lateral grooves extending from the shoulder main groove toward the inside in the tire axial direction, while decreasing the angle with respect to the tire circumferential direction, and the middle lateral grooves are each provided with a groove bottom sipe extending along the middle lateral groove and opened in the groove bottom of the middle lateral groove,
- wherein said shoulder land portion is provided with a shoulder sub groove extending continuously in the tire circumferential direction and having a smaller groove width than that of the shoulder main groove, so as to define a main portion on the outside in the tire axial direction of the shoulder sub groove and a secondary portion between the shoulder sub groove and the shoulder main groove, the secondary portion having a width in the tire axial direction which is 0.15 to 0.30 times the width in the tire axial direction of the shoulder land portion, and
- wherein the main portion is provided with a plurality of shoulder lug grooves extending from a tread edge toward the inside in the tire axial direction and terminating without being communicated with the shoulder sub groove.
Dependencies are inferred from the claim text.