US 4,043,725 AGranted

Apparatus for molding pneumatic vehicular tires

OwnerOskar Schmidtinventor

Life of this patent

Estimating the term…

Loading patent…

Abstract

A mold cavity for producing a pneumatic vehicular tire is radially expandable to form successive coaxial annular layers, e.g. carcass, reinforcing belt and tread, of the tire body. The mold cavity is defined by a stationary core, several outer annular mold walls alternately juxtaposable with the core, and a pair of opposite cheeks axially bracketing the core and the juxtaposed segments. The segments of each mold wall are movably mounted on a respective carrier ring and are radially outwardly retractable thereon to clear the cheeks whereby they can be axially moved into and out of alignment with the core. With successive operative positioning of segment sets of progressively increasing inner radii around the core, the mold cavity is expanded after each molding step preparatorily to formation of the next layer after partial hardening of the elastomeric material of the layer previously formed therein.

Claims10

Dependent claims

An apparatus for molding a pneumatic tire with a body formed from a plurality of coaxial annular layers of elastomeric material, comprising:

a frame;
a generally toroidal core on said frame centered on an axis;
a plurality of sets of mutually complementary ring segments with inner radii larger than the core radius, said inner radii being different for the several sets;
a plurality of carriers on said frame supporting the ring segments of respective sets with freedom of radial displacement, with reference to said axis, between an outwardly retracted position and a working position in which said segments complement one another to a continuous outer mold wall;
transport means coupled with said carriers for successively aligning the segments of sets with progressively larger inner radii with said core, the aligned segments in their working position defining with said core an annular mold cavity;
closure means on said frame positionable to seal said mold cavity against the outside preparatorily to admission of elastomeric material into said mold cavity;
and
actuating means on said frame coupled with said ring segments for displacing same between said retracted and working positions thereof.

5 more elements

Dependencies are inferred from the claim text.