Grooved-core tooling for manufacturing pneumatic tires reinforced by stays passing through the inflation cavity

A tool for manufacturing a toroidal tire that has a crown suitable for forming a tread, a first annular bead and a second annular bead designed to make it possible to attach the tire to a mounting support such as a rim, together with a first sidewall and a second sidewall that connect the crown to the first bead and to the second bead respectively, the crown, the first and second sidewalls, and the first and second beads as a whole forming a wall having a concave inner surface that defines a cavity of the tire, said tool comprising:

• a toroidal core having, about its central axis, a convex outer receiving surface, which has a shape conjugate to the inner surface of the wall of the tire and which comprises to this end a radially outer crown zone suitable for receiving components forming the crown of the tire and, axially on either side of said crown zone, a first lateral zone turned in towards the central axis and suitable for receiving components forming the first sidewall and the first bead, together with a second lateral zone turned in towards the central axis and suitable for receiving components forming the second sidewall and the second bead, so that the core embodies a reserved volume which is externally delimited by the receiving surface and corresponds to the cavity of the tire;
• the core having a plurality of passages that extend inside the reserved volume, below the receiving surface, and which open onto said receiving surface so that each of said passages connects the crown zone of the receiving surface to one of the first and second lateral zones so that the core can receive, inside said passages, stays which are designed to be permanently incorporated into the structure of the tire and each extend in the cavity of the tire, connecting a crown anchor point situated in the crown of the tire to a lateral anchor point situated in one of the sidewalls or beads of the tire;
• wherein the passages for stays are formed by grooves that are hollowed out from the receiving surface in a thickness of the reserved volume so that they have a continuous opening along the profile of the receiving surface, from the crown zone to the lateral zone in question,
• wherein the core comprises an assembly of a plurality of annular sub-assemblies comprising;
• i) a central ring, which forms a central portion of the crown zone of the receiving surface suitable for receiving one or more components forming the crown of the tire, said central ring being without passages for stays;
• ii) a left lug, which is axially adjacent to the central ring, said left lug comprising the first lateral zone of the receiving surface as well as a portion of the crown zone that axially extends the central portion of the crown zone on the corresponding side of the central ring, and said left lug containing the grooves forming the passages for the stays that connect the first sidewall of the tire to the crown of the tire;
• and
• iii) a right lug, which is axially adjacent to the central ring, on the side of the central ring that is axially opposite the side receiving the left lug, said right lug comprising the second lateral zone of the receiving surface as well as a portion of the crown zone that axially extends the central portion of the crown zone on the corresponding side of the central ring, and said right lug containing the grooves forming the passages for the stays that connect the second sidewall of the tire to the crown of the tire;
• wherein the central ring, the left lug, and the right lug are each angularly split into sectors azimuthally about the central axis, with keys designed to be accessible radially from an inside and to be removed first on a dismantling of the sub-assembly in question, and arch segments supported and locked in position by the keys, and designed to become maneuverable after they have been released by the removal of the keys.