| 摘要 |
PURPOSE: To adequately operate when a tire is employed on any axle, prevent the noise emission and behave in a uniform manner, irrespective of the road surface conditions by constituting grooves which separate the different ribs from each other by design units extending in circumferentially opposite directions and having deep and shallow sipes and long and short legs in which the intermediate portions of legs form angles in a predetermined range with respect to the equatorial plane. CONSTITUTION: In the tire tread structure, four circumferentially extending grooves 1-4 divide the tread into shoulder ribs 10, 14, intermediate ribs 11, 13 and a central rib 12, and zig-zag shaped repetitive design units of the edges of the grooves on either side thereof are constituted of short legs 5, 7, 35, 37 and long legs 6, 8, 36, 38 in the ratio of length of long leg to short leg being below 15. The ribs 11, 12, 13 are provided with deep sipes 40-42 and 43-45 and shallow sipes 50-52 and 53-55, and the portions 42, 45 and the portions 40, 43 are respectively situated in the continuation of the legs 5, 7 and the legs 35, 37. The intermediate portions 41 and 44 form with respect to the equatorial plane angles ranging respectively between 30 deg. and 70 deg. and between 50 deg. and 90 deg.. The tire having the tire tread structure adequately operates, even if employed on any axle such as a steering axle, a driving axle, a driven axle or the like and has a low noise emission and can behave in a uniform manner, irrespective of the road surface conditions. |
