Studless tire
AssigneeSumitomo Rubber Industries, Ltd.
InventorsKenji Hatakenaka, Kenichi Mineta, Akihiro Miyoshi
Life of this patent
Estimating the term…
Abstract
A studless tire with a tread pattern comprising blocks that are defined by longitudinal and transverse grooves and having at least one row of blocks that extends in the peripheral direction of the tire. The peripheral rows of blocks are such that at least one sub-block is provided within one pitch of the tread pattern outside an adjacent block in the tire's rotating axle. And the sub-block is separated from the block by a sub-groove less deep than the longitudinal and transverse grooves and has the longer side in the peripheral direction and the shorter side in the direction of the rotating axle.
Claims4
A studless tire comprising:
- a tread portion having a pair of tread ends including;
- first transverse grooves in a width direction of said studless tire, said first transverse grooves having a first depth,
- a first longitudinal groove on a center line of the tire through the ground contact area of said tread portion, said first longitudinal groove having said first depth,
- a pair of second longitudinal grooves, one on each side of the center line, each of said second longitudinal grooves having said first depth,
- a pair of third longitudinal grooves, one of said third longitudinal grooves being disposed between said first longitudinal groove and one of said second longitudinal grooves, the other of said third longitudinal grooves being disposed between said first longitudinal groove and the other of said second longitudinal grooves, each said third longitudinal groove having said first depth, each of said third longitudinal grooves including first portions and second portions such that the first portions and the second portions of the third longitudinal groove alternate and the first portions of the third longitudinal groove are offset from the second portions of the third longitudinal groove in the axial direction of the tire,
- fourth longitudinal grooves, each of said fourth longitudinal grooves being a subgroove and having a second depth which is shallower than said first depth, and
- fifth longitudinal grooves, each of said fifth longitudinal grooves being a subgroove and having said second depth wherein, on each side of the center line of the tire, said fourth longitudinal grooves are disposed between one of said third longitudinal grooves and said first longitudinal groove, said fifth longitudinal grooves are disposed between one of said second longitudinal grooves and one of said portions of one of said third longitudinal grooves adjacent thereto, said fourth longitudinal grooves and said fifth longitudinal grooves alternate in the circumferential direction and no fourth longitudinal groove is interposed between said one of said portions and said first longitudinal groove;
- and
- shoulder portions including buttress portions which extend radially inward from each said tread end, wherein
- said first transverse grooves and said first, second, third, fourth, and fifth longitudinal grooves form a tread pattern having a plurality of tread blocks and sub-blocks.
Dependencies are inferred from the claim text.