Patent ID: 9511556
Filing Date: 2016-12-06
CPC Classification: B29D

Claim Text:
1. A variable-diameter tire-building drum adapted for the manufacture of a green tire, comprising: a generally cylindrical receiving surface formed of radially mobile sectors and bearing elements that constitute 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, wherein disengageable locks keep the pushers in a position that the radially external surface of the sleeve is aligned with the receiving surface, wherein the keep of the pushers in the position is independent of the diameter to which the said receiving surface is brought, further comprising a mechanism able to alter the axial position of the mobile sectors between two extreme positions, wherein the mobile sectors reaching end stops in each of the extreme axial positions causes the locks to open or close respectively.