GB855873A - Improvements to outer covers of pneumatic tyres - Google Patents

Abstract

855,873. Pneumatic tyres. PNEUMATIQUES & CAOUTCHOUC MANUFACTURE KLEBER COLOMBES. March 12, 1957 [March 12, 1956], No. 8105/57. Class 144 (2). A pneumatic tyre has a carcase formed by an even number of layers of parallel-cord plies each disposed with a cord angle of from 75 to 85 degrees to the mid-circumferential plane of the tyre and the cords in half the number of layers symmetrically crossed with respect to those of the other half, and an even number of breaker, or crown reinforcing, layers of parallel-cord plies disposed with a cord angle of from 5 to 15 degrees to the mid-circumferential plane complementary to that of the carcase cords, and the cords in half the layers symmetrically crossed with respect to those of the other half. Figs. 1 and 2 show an arrangement of carcase plies 1, 2, 3, 4 which each have one side edge anchored to a bead, and the other side edge terminating adjacent the opposite edge of the tread, to provide two layers in each side wall, and four layers in the crown region which is additionally reinforced by two crown plies 5, 6. Fig. 3 shows a carcase of four plies 7, 8, 9, 10, the edges of each of which are anchored to both beads respectively with intermediate plies 11, 12 between the plies 8, 9 and 9, 10 respectively extending across the axial width of the tread, there being again two crown reinforcing plies 13, 14. In a further arrangement, Fig. 4, an inner bead to bead carcase ply 15 is surmounted by a tread width ply 16 and the carcase is completed by plies 17, 18, anchored one to each bead, which overlap in the crown region beneath the crown reinforcing plies. In all cases the cords may be of metallic, or natural or synthetic textile material. Reference has been directed by the Comptroller to Specifications 700,435 and 769,325.