Patent ID: 7000663

Claim:
A shaping drum for tire carcasses, comprising: a barrel having a central axis; two axially spaced bead-holding systems carried by the barrel for holding respective ones of the beads of a tire carcass to be shaped; a plurality of plates carried by the barrel, said plates being arranged circumferentially around said central axis and having radially outer surfaces defining a receiving surface for the tire carcass; a mechanical expansion mechanism comprising, for each plate, two arms which are articulated between a first clevics for each said plate and a first crown which is axially displaceable on the barrel, and a counter-arm articulated between one of said arms and a second crown mounted fixedly on the barrel, and permitting displacement of the plates radially between a retracted position and an expanded position of the drum by axial displacement of the first crown in combination with the locking generated by the counter-arm and the second crown; a second clevis integral with the radially inner side of each plate and articulated relative to the first clevis for pivotal movement of said plate about an axis parallel to said central axis; and guide means on each plate, the inner side of each plate bearing against the guide means of an adjacent plate, for positioning of the radially outer surface of each plate at the same radial distance from said central axis in the expanded position of the drum and for permitting tilting of the plates articulated thereto such that the plates are circumferentially superimposed on each other at least in part in the retracted position of the drum.