TYRE BUILDING DRUM

摘要

Variable-diameter building drum intended for the manufacture of a green tire having a generally cylindrical receiving surface formed of radially mobile sectors and bearing elements the radially external part of which constitutes the receiving surface, the receiving surface comprising at least one circular groove containing an elastic circumferential sleeve which is held radially away from the bottom of the groove by pushers able to move radially with respect to the mobile sectors so as to align the radially external surface of the sleeve with the receiving surface when the drum is brought to a first laying diameter, and which is pressed against the bottom of the groove under the effect of circumferential elastic tensions when the drum is placed at a laying diameter greater than the said first laying diameter. Disengageable locks are able to keep the pushers in the position in which the radially external surface of the sleeve is aligned with the receiving surface regardless of the diameter to which the said receiving surface is brought.