Apparatus for runnerless injection-compression molding thermosetting materials

An improved injection-compression molding apparatus comprising:

• a stationary assembly comprised of:
• a stationary platen member,
• a heat plate mounted thereon, means to heat said plate, and
• a plurality of mold faces with runner channels mounted on said heat plate;
• a moveable assembly comprised of:
• a moveable platen member,
• a heat plate mounted thereon, means for heating said plate, and
• a plurality of mold faces mounted on said heat plate corresponding to and positioned to be aligned with the mold faces on said stationary assembly to form a plurality of mold cavities;
• p1 a feed nozzle assembly comprised of:
• a housing having a closed end and an open end,
• said open end adapted to be attached to the injection barrel of an injection molding machine,
• said closed end and interior of said housing forming an internal chamber,
• said internal chamber narrowing along a portion thereof to form a constricted zone,
• the portion of said housing adjacent said constricted zone containing a means for controlling the temperature within said constricted zone,
• said housing having a plurality of feed outlets positioned along the outside periphery thereof contiguous to said closed end, and
• said feed outlets connecting with said internal chamber;
• wherein said moveable heat plate has a temperature-controlled area comprised of a temperature-controlled plate member aligned with the closed end of said nozzle member, said plate having operably connected means for maintaining its temperature lower than that at which any substantial curing of the thermosetting molding material will occur but sufficiently high to maintan the molding material in a plasticized condition;
• means to move said moveable assembly to bring said moveable mold faces into close proximity and aligned with corresponding faces in said stationary assembly to form partially open mold cavities and runner channels connected to the exterior of the mold cavities,
• means for feeding a supply of plasticized thermosetting molding material into the open end of said nozzle member, through said feed outlets, through said runner channels and into said partially open mold cavities,
• means to seal off said runner channels to retain molding material in the mold cavities during the curing cycle,
• means for closing said partially open mold cavities to compress and cure the thermosetting material enclosed within the mold cavities by pressure and heat, and
• means for retracting said movable to separate said mold faces and remove a molded article.

An improved injection-compression molding apparatus comprising:

• a stationary assembly comprised of:
• a stationary platen member,
• a heat plate mounted thereon, means to heat said plate, and
• a plurality of mold faces with runner channels mounted on said heat plate;
• a moveable assembly comprised of:
• a moveable platen member,
• a heat plate mounted thereon, means for heating said plate, and
• a plurality of mold faces mounted on said heat plate corresponding to and positioned to be aligned with the mold faces on said stationary assembly to form a plurality of mold cavities;
• a feed nozzle assembly comprised of:
• a housing having a closed end and an open end,
• said open end adapted to be attached to the injection barrel of an injection molding machine,
• said closed end and interior of said housing forming an internal chamber,
• said internal chamber narrowing along a portion thereof to form a constricted zone,
• the portion of said housing adjacent said constricted zone containing a means for controlling the temperature within said constricted zone,
• said housing having a plurality of feed outlets positioned along the outside periphery thereof contiguous to said closed end, and
• said feed outlets connecting with said internal chamber;
• wherein the stationary heat plate has a temperature-controlled sleeve member therein, positioned to surround the housing member of said nozzle assembly and separate said heat plate from said housing;
• means to move said moveable assembly to bring said moveable mold faces into close proximity and aligned with corresponding faces in said stationary assembly to form partially open mold cavities and runner channels connected to the exterior of the mold cavities,
• means for feeding a supply of plasticized thermosetting molding material into the open end of said nozzle member, through said feed outlets, through said runner channels and into said partially open mold cavities,
• means to seal off said runner channels to retain molding material in the mold cavities during the curing cycle,
• means for closing said partially open mold cavities to compress and cure the thermosetting material enclosed within the mold cavities by pressure and heat, and
• means for retracting said moveable assembly to separate said mold faces and remove a molded article.

An improved injection-compression molding apparatus comprising:

• a stationary assembly comprised of:
• a stationary platen member,
• a heat plate mounted thereon, means to heat said plate, and
• a plurality of mold faces with runner channels mounted on said heat plate;
• a moveable assembly comprised of:
• a moveable platen member,
• a heat plate mounted thereon, means for heating said plate, and
• a plurality of mold faces mounted on said heat plate corresponding to and positioned to be aligned with the mold faces on said stationary assembly to form a plurality of mold cavities;
• a feed nozzle assembly comprised of:
• a housing having a closed end and an open end,
• said open end adapted to be attached to the injection barrel of an injection molding machine,
• said closed end and interior of said housing forming an internal chamber,
• said internal chamber narrowing along a portion thereof to form a constricted zone,
• the portion of said housing adjacent said constricted zone containing a means for controlling the temperature within said constricted zone,
• said housing having a plurality of feed outlets positioned along the outside periphery thereof contiguous to said closed end,
• said feed outlets connecting with said internal chamber;
• and
• said feed nozzle assembly positioned such that feed outlets project beyond said stationary assembly;
• means to move said moveable assembly to bring said moveable mold faces into close proximity and aligned with corresponding faces in said stationary assembly to form partially open mold cavities and runner channels connected to the exterior of the mold cavities, whereby said feed nozzle assembly is fixedly positioned with respect to said stationary assembly,
• means for feeding a supply of plasticized thermosetting molding material into the open end of said nozzle member, through said feed outlets, through said runner channels and into said partially open mold cavities,
• means to seal off said runner channels by movement of said moveable assembly with respect to said fixed nozzle assembly and said stationary assembly to retain molding material in the mold cavities during the curing cycle,
• means for closing said partially open mold cavities to compress and cure the thermosetting material enclosed within the mold cavities by pressure and heat, and
• means for retracting said moveable assembly to separate said mold faces and remove a molded article.