Radial tire building drum

摘要

A radial tire building drum for forming a radial tire green case having bead portions into a toroidal shape, includes a drive shaft rotatable about a center axis of rotation and movable in a fore-and-aft direction thereof, a pair of drum units carried on the drive shaft and having a common center axis of rotation which is in axially alignment with the center axis of the drive shaft, the drum units being axially movable toward and away from each other along the center axis of the drive shaft by driving at least one of the drum units to move along the common center axis of rotation, a plurality of arcuate drum segments each retained to the pair of drum units and formed with an annular groove circumferentially extending therethrough, each of the arcuate drum segments being radially movable toward and away from the common center axis. The drum further includes a pair of annular rubber sealing members for hermetically sealing space defined by the green case and the pair of drum units and each having a radially inner end portion, a radially outer end portion and a bellows portion intervening between the radially outer end portion and the radially inner end portion, the radially inner end portions being supported by the drum units, the radially outer end portions being tightly received in the annular grooves formed in the arcuate drum segments.