摘要 |
1,189,445. Moulding pneumatic tyres. DUNLOP CO. Ltd. 4 Aug., 1967 [6 Aug., 1966], No. 35300/66. Heading B5A. [Also in Division B7] Apparatus for moulding at least the tread portion of a pneumatic tyre comprises a generally annular tread moulding matrix having on its radially-inner surface at least one generally circumferential flange for moulding a groove 2 in the tread and at least one circumferential groove for moulding a rib 1 in the tread, a plurality of circumferentially spacedapart transversely-extending blades extending radially inwardly of the base of the groove for moulding corresponding transversely-extending slots 3 in the tread rib, the width of the slots being smaller than the width of the groove, and one or more generally circumferential blades extending radially inwardly of the base of the groove for moulding a corresponding slot 4 or slots in the tread rib, said blade or blades intersecting some at least of the transversely extending blades. Each circumferentially extending blade may be provided with a portion which is wider in cross-section than the remainder of the blade, preferably located at the radially innermost edge. The widened portion may be circular or oval in cross-section. The term "generally circumferential" means parallel to or at an angle of not greater than 45 degrees to a circumferential line of the tyre and includes zig-zag and diagonal configurations. The term "transversely extending slots" means slots extending in a direction at any angle but not parallel to a circumferential line of the tyre and includes rectilinear, curved, wavy and zig-zag configurations.
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