| 摘要 |
PURPOSE:To reduce pattern noises while maintaining wandering and water dischargeability by forming a land part by disposing a plurality of grooves on a cylindrically extending tread part and specifying the sectional forms of the grooves positioned on the outside of the width direction of the tread part. CONSTITUTION:Four grooves 2 extending zigzag in a tire circumferential direction are disposed on a tread part 1 and five ribs 3 are formed. S formed sipes 4 opened in the grooves on both side in a width direction sandwiching the ribs are provided on the second ribs 3-2 out of the five rib s 3 and shoulder sipes 8 extending from a shoulder rib 3-3 to a buttress 7 are provided in the vicinity of a tread width end 6. In this case, in the groove 2, an opening 20 opened on the surface of the tread part and a following side wall 22 are extended toward the inner side of a tire radial direction while curvature radius R makes a projecting curve of 2.1mm and narrows a groove width and a groove width at the narrowest part 26 is formed 40% of an opening groove. Thus, pattern noises can be reduced. |
