Patent ID: 8991449
Filing Date: 2015-03-31
Classification: B60C

Abstract:
1. A pneumatic tire including a tread portion, said tread portion comprising: four main circumferential grooves having groove width HG of not less than 4 mm consisting of a pair of axially inner main circumferential grooves extending on both sides of the tire equator in the tire circumferential direction, and a pair of axially outer main circumferential grooves located on the outer side of said axially inner main circumferential grooves, a central land portion provided between said axially inner main circumferential grooves, a pair of middle land portions each provided between one of said axially inner main circumferential grooves and one of said axially outer main circumferential grooves, and a pair of shoulder land portions each provided between one of said axially outer main circumferential grooves and a ground contact edge of the tread, wherein each of said central land portion, said middle land portions and said shoulder land portions is divided into a plurality of blocks by axial grooves across each land portion, wherein the blocks are aligned in the circumferential direction, and a sipe is provided on each block, each of the axial grooves provided in each of said middle land portions comprises an axially inner portion and an axially outer portion, said axially inner portion is inclined with respect to an axial direction of the tire and has a groove width increasing axially outwardly, said axially outer portion is inclined in opposite direction with respect to said axially inner portion and has a groove width increasing axially outwardly, said axially inner portion and said axially outer portion are connected to form a V-shape, said central land portion has an axial width We being 10% to 15% of a tread ground contacting width TW, each of said middle land portions has an axial width Wm being 15% to 22% of the tread ground contacting width TW, each of said shoulder land portions has an axial width Ws being 15% to 22% of the tread ground contacting width TW; and each of only said middle land portions comprises a straight narrow circumferential groove extending in the circumferential direction of the tire and having a groove width Hg of 2 to 6 mm so as to divide said each middle land portion into an axially inner part and an axially outer part located on the inner side and the outer side of said narrow circumferential groove.