GB833994A - Improvements in or relating to pneumatic tyres - Google Patents

Abstract

833,994. Tubular tyres. DUNLOP RUBBER CO. Ltd. Nov. 30, 1956 [Dec. 16, 1955], No 36089/55. Class 144 (2). A tubular cycle tyre comprises a band 1 formed from convolutions of filamentary material, such as rubberized cotton cord progressively wound in continuous lengths in oblique zig-zag fashion from side to side on the exterior of a former, the included angle between the continuous lengths at each edge of the winding being substantially less than 180 degrees and the winding having a slight lag or lead to provide a double layer band which at any cross-section shows parallel obliquely-directed lengths in each layer with those in one layer being oppositely directed to those in the other layer, and the band being enveloped around a valved inner tube and having its edges 4, 5 secured together at the inner periphery 6 of the tubular tyre so formed. As shown, an annular internal tongue of tape is sewn to one edge of the band to overlap the abutting edges 4, 5 of the tyre, the edges 4, 5 being then sewn together by thread 7 and the sewn joint finally being covered by a tape 8. A pre-vulcanized tread 9 is adhered to the tyre, and the inner tube may be vulcanized to the tyre to provide a " tubeless " construction. In alternative arrangements, the cord winding may be such that each length thereof across the width of the band 1 may extend at different angles to the circumferential lineX-X over different parts of said length. In place of the sewn joint 7, the edges 4, 5 of the band may be joined by vulcanization thereto of the tongue 3. Specification 808,341 is referred to.