| 摘要 |
976,497. Pneumatic tyres. PIRELLI S.p.A. Nov. 19, 1963 [Dec. 5, 1962], No. 45577/63. Addition to 864,909. Heading B7C. In order to permit the distribution of concentrated stresses or shocks and to give a greater protection against punctures, the replaceable tread tyre disclosed in the parent Specification is modified by the provision of at least one pair of layers 3, 4 of metallic cords disposed radially outwardly with respect to the cincture 2, the cords being parallel to one another in each layer with the cords in one layer being crossed with respect to the cords in the other layer symmetrically with respect to the mid-plane of the tyre. The cord angle of the layers 3, 4 may be between 25 and 65 but is preferably between 30 and 50 degrees to the mid-plane of the tyre, and the diameter of the cords in these layers is preferably one-third of the diameter of the cincture cord. |
