TIRE BUILDING MACHINE DRUM

摘要

A contractible tire building drum having segmental cylindrical shoulder rings with flanges at the ends and a stretchable bladder positioned over and between the shoulder rings. Each of the shoulder rings has a primary set of segments and a secondary set of segments alternately spaced around the ring. The primary and secondary sets of segments are retractable from positions in the cylindrical shoulder ring to a nested position radially inward. Guide means are provided to displace the secondary segments in an axial direction during retraction of the segments so that the secondary segments are axially displaced from the primary segments with the flanges of the secondary segments overlapping the flanges of the primary segments.