Patent ID: 6209602
Filing Date: 2001-04-03
Classification: B60C

Abstract:
A pneumatic agriculture tire for an industrial type tractor having a maximum section width (W), an axis of rotation, an equatorial plane (EP), centered between the maximum section width and being perpendicular to the axis, a casing having a belt reinforcement structure and a carcass reinforced with rubber coated cords, a rubber tread disposed radially outwardly of the carcass, the tread being divided on each side of the equatorial plane (EP) into a first and a second tread half, the tread has a pair of lateral tread edges, the distance between the tread edges defines the tread width, the tread has an inner tread and a plurality of tread lugs projecting radially from the inner tread, the tread lugs including:a plurality of central lugs arranged in a circumferentially continuous row and extending across the equatorial plane (EP), each central lug is inclined relative to the equatorial plane (HP), each central lug having a leading end and a trailing end, each leading end and each trailing end having an enlarged lug head, the leading end of each central lug being located on an opposite side of the equatorial plane (EP) relative to the trailing end of the same central lug, the central lugs having a length of about 30% of the tread width;a plurality of shoulder lugs divided into first and second rows each row of shoulder lugs extending from each of the lateral tread edges toward the equatorial plane of the tire, the shoulder lugs having an axially inner end being axially spaced from a leading end and a trailing end of axially adjacent central lugs, the shoulder lugs having an overall lug length of greater than 30% of the tread width, each shoulder lug being located within one tread half, the shoulder lugs and central lugs are axially spaced at the outer surface of the lugs such that the axially inner ends of the first and second rows of shoulder lugs are axially aligned within each respective row, and the leading ends and trailing ends of the central lugs are respectively axially aligned, a plane P.sub.1 tangent to the axially inner ends of the first row of shoulder lugs is spaced an axial distance d.sub.1 from a plane C.sub.T tangent to the trailing ends of the central lugs, and a plane P.sub.2 tangent to the axially aligned inner ends of the second row of shoulder lugs is spaced a distance d.sub.2 from a plane C.sub.L, the plane C.sub.L being tangent to the leading ends of the central lugs, the tread being characterized in that the distances d.sub.1 and d.sub.2 each being at least 5% of the tread width and forming two circumferentially continuous straight channels around the periphery of the tread.