IT1036408B - SAFETY PNEUMATIC - Google Patents

Abstract

1507082 Pneumatic tyres PNEUMATIQUES CAOUTCHOUC MANUFACTURE ET PLASTIQUES KLEBER-COLOMBES 24 June 1975 [2 July 1974] 26810/75 Heading B7C A pneumatic tyre provided in each side wall with an annular chamber 20, which extends from adjacent the associated bead to adjacent the associated shoulder, has an annular rubber element 30 adhered to the inner surface of the carcass in each shoulder region of the tyre. The chambers 20 may each be inflated via a valve (not shown) in its wall 17 to a pressure higher than that of chamber 15. Alternatively, the chambers 20 may each contain a flexible cellular material. The carcass reinforcement may comprise a single ply of cord fabric 21 the edges of which may overlap or terminate as illustrated in Fig. 1, or may comprise two plies 21a, 21b (Fig. 3). The cords may be radial, or oblique with cords in adjacent plies crossing. The plies may be interrupted in the crown of the tyre. Further, reinforcing fabric strips 24, 25 may be provided. In the tyre of Fig. 3, the plies 21a, 21b may comprise metal and textile cords respectively in order that the inner walls 18 may be stiffer than walls 17. The differing stiffnesses may be achieved by a higher filament density or heavier filaments for the inner ply or a harder rubber for the inner ply. The walls 17, 18 may alternatively each be reinforced by one or more layers of a rubbery mixture containing, preferably orientated fibres. Support pads 31 (32) may be provided on the sidewalls and/or the tread and may comprise a self-lubricating rubber or may be covered with a layer of friction-less material. The apex strips 29 may extend into the inner walls 18 (Fig. 5, not shown) in which case chafer strips (26) are provided which extend from each bead seat into the outer walls 17.