US 12,441,071 B2
Process and plant for producing tyres for vehicle wheels
Davide Conti, Milan (IT); Christian De Col, Milan (IT); and Gianni Enrico Portinari, Milan (IT)
Assigned to PIRELLI TYRE S.P.A., Milan (IT)
Appl. No. 17/781,327
Filed by PIRELLI TYRE S.P.A., Milan (IT)
PCT Filed Dec. 18, 2020, PCT No. PCT/IB2020/062169
§ 371(c)(1), (2) Date May 31, 2022,
PCT Pub. No. WO2021/124237, PCT Pub. Date Jun. 24, 2021.
Claims priority of application No. 102019000024694 (IT), filed on Dec. 19, 2019.
Prior Publication US 2023/0001657 A1, Jan. 5, 2023
Int. Cl. B29D 30/22 (2006.01); B29D 30/20 (2006.01); B29D 30/24 (2006.01); B29D 30/26 (2006.01); B29D 30/70 (2006.01)
CPC B29D 30/22 (2013.01) [B29D 30/242 (2013.01); B29D 30/2607 (2013.01); B29D 30/70 (2013.01); B29D 2030/202 (2013.01); B29D 2030/209 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A process for producing tyres for vehicle wheels, comprising building a crown structure of the tyre, wherein building said crown structure comprises:
building a crossed belt structure on a substantially cylindrical first forming drum arranged in a first working area;
transferring said crossed belt structure from said first forming drum to a stationary annular holding member, the annular holding member arranged in a first service area which is downstream of said first working area with respect to a first direction of movement;
arranging a radially contractable/expandable second forming drum in a radially inner position with respect to said annular holding member;
transferring said crossed belt structure from said annular holding member to said second forming drum by radially expanding said second forming drum until said second forming drum is brought into an expanded condition in which said second forming drum is in contact with said crossed belt structure so as to toroidally shape said crossed belt structure; and
depositing at least one zero degrees belt layer on said second forming drum in a radially outer position with respect to said toroidally-shaped crossed belt structure;
wherein building said crown structure comprises, after having transferred said crossed belt structure from said first forming drum to said annular holding member:
moving said first forming drum along the first direction of movement from the first service area to a second service area arranged downstream of said first service area with respect to said first direction of movement and comprising a first support member; and
transferring said first forming drum to said first support member.