Vent apparatus for an injection mold
AssigneeGenCorp Inc.
InventorJames K. Brew
Life of this patent
Estimating the term…
Abstract
A closed injection mold for molding liquid resins into molded plastic articles containing at least one vent apparatus having a reciprocating vent pin operative to retract to open the vent opening and extend to close the vent opening. Each vent apparatus is responsive to a full resin level in the mold cavity to close the vent opening. When the vent opening is closed, cleansing fluid is automatically circulated through the debris charge line of the vent apparatus to clear the venting channels prior to the resin debris hardening.
Claims8
A mold wherein a liquid molding resin is injected into a closed mold cavity where the liquid resin is hardened in the mold, said mold having at least one vent opening communicating with a venting means for expelling air from the mold cavity the improvement comprising;
- said venting means comprising a vent tube having an interior channel communicating with the vent opening in the closed mold and with a debris discharge channel;
- a reciprocating means having a reciprocating vent pin slidably engaging the interior channel of the vent tube, the vent pin being operative to extend and close the vent opening and to retract and open the vent opening;
- and
- a purging channel interconnected and communicating with the interior channel of the vent tube and with said discharge channel.
Dependencies are inferred from the claim text.