ULTRASONIC SPLICING OF RUBBER COATED FABRIC

1386732 Seaming non-metallic sheet material FIRESTONE TIRE & RUBBER CO 1 Feb 1973 [7 June 1972] 5200/73 Heading B5K The edges of two reinforcing cord-fabric plies having a coating of a compound of natural or synthetic rubber which is not vulcanized or cross-linked, the cords of each ply being parallel to each other and to said edges, are butt joined by bringing said edges together with the cords in each ply arranged parallel to the cords in the other ply and subjecting said abutting edges to sonic or ultrasonic vibrations to join the edges without causing cross-linking or vulcanization of the compound. The fabric, e.g. tyre cord fabric, may comprise parallel cords of rayon, nylon, polyester, steel or glass. In splicing apparatus, Fig. 1, a power source (not shown) supplies electrical energy to six converters 11 which change electrical energy into mechanical energy and which are connected to six boosters 12 which increase the magnitude of the mechanical energy. The boosters 12 are connected to separate (ultra)sonic horns 13 which are brought into contact with and apply a predetermined pressure to the plies 40 to be spliced by hydraulic or pneumatic cylinders 14. These plies 40 are supplied by a conveyer belt 20. To ensure that the pressure applied during splicing is uniform, the belt 20 is backed by plates 30 supported by an air bag 31.