Expandable mandrel having adjustable width

Abstract

A rotatable drum useful in the manufacture of vehicle tires. A plurality of segments collectively define the outer circumferential surface of the drum. These segments are divided into two sets, one set being disposed on each of the opposite sides of a transverse center plane of the drum, the center plane being oriented normal to the rotational axis of the drum. The two sets of segments are mounted for selective positioning thereof axially of the drum from a location external of the drum to adjust the overall working width of the drum. Further, the segments are selectively positionable between expanded positions radially of the rotational axis of the drum to provide a relatively continuous circumferential outer surface of the drum for the layup of a tire carcass thereon, and collapsed positions radially of the drum to permit the removal of a formed toroidal carcass from the drum. Movement of the plurality of segments of each of the two sets of segments radially of the rotational axis of the drum is effected by “slaving” the two sets of segments off a central mechanism which controls the radial positions of all the segments simultaneously and equidistantly from the rotational axis of the drum, while further providing for axial movement of the two sets of segments relative to one another while the segments are positioned at any given radial location of the segments.