| 摘要 |
1,026,431. Pneumatic tyres. PIRELLI S.p.A. Jan. 16, 1964 [Feb. 2, 1963], No. 1975/64. Heading B7C. A pneumatic tyre of the replaceable tread type comprises a tyre casing 1 provided on its radially outer surface with at least three circumferentially extending, axially spaced ridges, the two outer ones forming locating shoulders, and a single tread ring 2 adapted to extend from shoulder to shoulder across the casing and provided on its radially inner surface with one or more circumferential grooves to accommodate the ridge or ridges 7, 8 of the casing which is or are axially spaced from the casing shoulders, the tread ring 2 being provided (a) with a plurality of axially spaced reinforcements 12, 13 disposed in the tread ring adjacent its radially inner surface and extending transversely of the tyre in a curve or curves over the axial regions of the tread ring defined by the groove or grooves, each reinforcement being constituted by parallel cords which extend substantially circumferentially of the tread ring, and (b) with at least two superposed strips 14, 15 of parallel cord fabric disposed radially outwardly of the reinforcements 12, 13 and having an axial width substantially equal to that of the tread surface, the cords of each strip making an angle ranging from 20 to 60 degrees with the mid-circumferential plane of the tyre. When the tread ring is provided with three or more axially spaced reinforcements the radius of curvature of the axially outermost reinforcements is smaller than the radius or radii of curvature of the remaining reinforcement or reinforcements in a transverse section of the tread ring. The casing has a radial cord carcass. |
