GB321937A - Improvements in methods of and apparatus for curing inner tubes - Google Patents

Abstract

321,937. Firestone Tyre & Rubber Co. (1922), Ltd., (Firestone Tire & Rubber Co.). Aug. 17, 1928. Vulcanizing processes.-A tubular unvulcanized annulus is first inflated, nearly to its finished size, on a former on which it is manipulated to remove twists and bring the longitudinal splice or thickened portion around its inner periphery. The tube is removed, without deflation, from the former, placed in a mould, further expanded. and vulcanized. The apparatus described comprises a table 10 carrying a rotatable former 16 on which the tube is inflated by air or carbondi-oxide from a tank 11, and a mould 18. For ordinary tubes, the former is shaped as shown in Fig. 1, but for tyre-sectioned tubes having a thick inner peripheral portion, the former is shaped as shown in Fig. 4. The mould comprises the usual jacketed portions 18a, 18b to which steam or other heating medium is supplied from a pipe 25 through a valve 26, rigid and flexible pipes 27. 31 to the upper and lower portions 18<b>, 18<a> respectively. The upper portion has two outlet pipes 47, 54 and the lower portion a single outlet 39 provided with sand traps 51, 59, 41 and connected through a pipe 43 and valve 61 to a steam trap 62. Water, for cooling the mould, may be admitted from a pipe, not shown, through the pipes 27, 31, and a thermometer is arranged in a branch 45 of pipe 43. For complete inflation of the tube in the mould, air is fed from tank 11 through pipe 63 and flexible coil 64 to a valve 65 adapted to be connected to the valve stem of the tube.