| 摘要 |
PURPOSE:To narrow the distance between ridges or rows and generate a high tractive force on the work in plowland of paddy field and plowed field by specifying the width of lug row composed of lugs, the ratio of the width of lug row to a drop amount from the maximum radius of tire and tire width directional inner angle of the lugs. CONSTITUTION:A plurality of staggered lugs 14 are provided in the peripheral direction on both sides of the equatorial surface on the peripheral portion from the neighborhood of an equatorial surface 16 on the tread portion 12 of a tire 10 to a side wall portion 13. In this case, the grounding shape of each lug 14 is approximately linear wherein a width directional inner angle alpha between a front side ridgeline 14c in the rotational direction at the width directional outer edge and the rotational direction A is set in a range from 30 to 55 degrees. A width TW of the lug row composed of the lug 14 is not more than maximum width SW of a portion not including the tread 12 (the side wall portion 13). Further, the ratio D/TW of a fall height D, from the maximum radius, of an intersection P of an extension line M to be extended along an outer contour line 14A from neighborhood of the equatorial surface 16 to and an extension line N to be extended from an outer side 14D in the width direction of the lug 14 to outside in the radius direction is set in a range from 0.5 to 3%. |
