Drum for a play in forming raw pneumatic

摘要

Drum for a play in forming raw pneumatic.It is described a drum forming into a piece of raw tyre comprising lower zones formed of a reinforcement ring circular moves in rotation around an axis XX 39, comprising means for retaining the bead (2a, 2b) mounted opposite one another on a spindle cent Ral (1), each of said means of retention of bead comprising a support (5a)5B) mounted axially mobile manner in relation to said spindle (1), a set of segments of return (9a, 9B) distributed ring around the axis XX 39 , flowing radially between two circular rings (6a, 7a, 6b, 7b) fixed on the support (5a, 5b). Comprising a headquarters Receipt of the bead (10a, 10b), and a membrane reversal (12a.12b) which can slide on the seat of the receipt of the ticket, anchored in a manner airtight by its two ends (121a, 122a, 121b, 122b) on the circumference radially outer circular rings (6a, 7a, 6b, 7b) and anchored mechanically by appropriate means (14a, 14b) in the segments of Take (9a, 9B) along the line of the anchoring circumferential (90 a ).The said drum is characterized in that the section of the seat receiving the bead (10a, 10b) is of essentially circular shape with a length developed L1, and the line of the circumferential membrane anchor reversal (121, 12b) in return segments (9a, 9B) is displaced axially Toward the center of the drum in a length L2 on the seat for receiving the bead (l0a, 10b)The length L2 being between 0.7 and 2 times the length L1.