| 摘要 |
PURPOSE:To lower noises by specifying the length of a lug groove, the quantity of deflection by load and the surface area of the lug groove in a lug tire. CONSTITUTION:The area of the entire surface of the whole lug grooves 5a in a lug tire in which the length l of the lug grooves 5a measured along the meridian of the tire is brought to 33-43% of tire width W and deflection delta at a time when JIS reference load is used as load under reference air pressure is brought to 0.170 or less of the height H of a tire section is brought to 18-27% of the area of the entire surface of a tread surface. The number of pitches of the lug grooves 5a is brought to 3.6(D/S)<1/2>-4.5(D/S)<1/2> [where D represents the diameter (mm.) of the equator of the tire and S the nominal width (inch) of the tire]. A noise level on an actual travelling can be lowered at that time. |
