| 摘要 |
PURPOSE:To surely prevent separation of plies by disposing a covering ply which is made of organic fiber as wide as covering the uppermost ply, on a belt lamination of a plurality of the plies which are interposed between the tread part and the carcass of the tyre described in the heading. CONSTITUTION:In a tyre described in the heading which has a belt lamination 10 disposed between a tread part and a radial ply carcass at the crown part thereof, a belt lamination 10 is built up by the first to the third plies 11-13 each of which is made of steel cord. The cord angle of the first ply 11 is set within the range of approximately 50 deg.-70 deg. with respect to the circumferential direction of the tyre. The cord angle of the second ply 12 is determined within the range of approximatey 10 deg.-20 deg. with respect thereto and inclined in the same direction as that of said ply 11 and the width thereof is determined greater than that of each of the first and third plies 11 and 13 and approximately equivalent to that of the tread. A covering ply which is made of organic fiber of 10<5>kg f/cm<2> or more in initial modulus and is wider than the third ply 13 is disposed on the aforesaid belt lamination 10. |
