초록 ▼

An apparatus is provided for injection molding a pneumatic tire having corresponding symmetrical parts such as the sidewalls of the tire which are geometrically symmetrical and have substantially the same physical characteristics. The apparatus involves means for providing a feed stream of suitable

An apparatus is provided for injection molding a pneumatic tire having corresponding symmetrical parts such as the sidewalls of the tire which are geometrically symmetrical and have substantially the same physical characteristics. The apparatus involves means for providing a feed stream of suitable plastic or elastomeric compound such as rubber, separating the feed stream into intermediate streams and remixing the intermediate stream before injection into the mold. The compound is injected into the mold cavities at uniformly spaced points along at least one of the annular zones of the cavity. The feed stream is preferably separated into two streams, one of which comes primarily from the outer portion of the stream and the other predominantly from near the center of the stream and then these streams are intermixed to provide a stream which is substantially uniform in composition throughout. Similarly prepared streams are injected into the two parts of the mold cavity which form a pair of symmetrical parts of the tire such as the two sidewalls.

대표청구항 ▼

An apparatus for the injection molding of pneumatic tires, comprising in combination with a mold provided with cavities arranged to generate symmetrical parts of the tire having the desired geometrical characteristics, at least one primary feed-conduit for a primary feed stream of fluid molding comp

An apparatus for the injection molding of pneumatic tires, comprising in combination with a mold provided with cavities arranged to generate symmetrical parts of the tire having the desired geometrical characteristics, at least one primary feed-conduit for a primary feed stream of fluid molding compound; a first means, for drawing, from said primary feed-conduit, first intermediate streams predominantly formed from the outer strata of said primary feed stream; a second means, for drawing, from said primary feed conduit, second intermediate streams predominantly formed from the axial strata of said primary feed stream; a third means, for combining, at least one of each of said first and second intermediate streams, to form a combined stream; and a plurality of injection conduits, each one for an injection stream drawn from said combined stream, for filling a mold cavity corresponding to each part of every pair of symmetrical parts of the tire, with fluid molding compound contained in said injection stream.