GB867338A - Double pneumatic tyre for vehicles - Google Patents

Abstract

867,338. Pneumatic tyres. ECKERT, W. Nov. 14, 1958, No. 36641/58. Class 144 (2). In a pneumatic tyre comprising two carcases 1 side-by-side joined by an integral common tread 4, 5 which is reinforced by a fabric layer 2 and defines a space 6 between the carcases, the tread surface is coplanar across the width thereof and is profiled on each side portion 5 to provide interrupted circumferential shoulder ribs a, interrupted circumferential ribs band narrower continuous circumferential ribs c, the various ribs being separated by circumferential grooves d and the centre portion 4 of the tread comprising groups of transverse blocks e, f separated circumferentially by large rectangular recesses g. As shown, the two carcases 1 are mounted on separate multi-piece rims 8 connected by a bridge-piece defining the inner periphery of the annular space 6, the bridge having apertures 9 for circulation of air. The tread recesses g overlie the space 6 and are each provided in the base thereof with an integrallyhinged flap 12 cut from the tread rubber radially outwardly of the fabric layer 2 and serving to control circulation of air from the space 6 through holes in the fabric layer 2 and the underlying tread rubber. The tyre carcases 1 may be used with or without tubes.