| 摘要 |
1281958 Pneumatic tyres FIRESTONE TIRE & RUBBER CO 13 July 1970 [8 Aug 1969] 33955/70 Heading B7C [Also in Division D1] A pneumatic tyre comprises a crossply carcass and a breaker each of parallel cord plies, the cord angle of the breaker plies being less than or equal to that of the carcass plies and the cords of the breaker plies being of 1650/2 denier rayon and having a twist in the range of 4.8 x 4À8 to 9 x 9 turns per inch, which is 40-75% of the more often used twist for this denier. The breaker comprises plies 15, 16 of parallel rayon cords while the carcass plies 12, 13 are of rayon, nylon or polyester. The breaker cords may be inclined from 21 to 35 degrees to said plane and the carcase cords from 30 to 45 degrees, and 1100/2, 2200/3 or 1650/3 denier cords with twists within the ranges 5À6 Î 5À6 to 11À25 Î 11À25, 4 Î 4 to 7À5 Î 7À5 or 3À4 x 3À4 to 6À38 x 6À38 respectively, may be used. |
