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US 4,799,876 AGranted
Blow molding apparatus
AssigneePhillips Petroleum Company
InventorDonald L. Peters
Life of this patent
Estimating the term…
Abstract
Blow molding of a parison with a blow needle is aided by the use of a sealing member which includes at least one projection which completely surrounds the blow needle. During inflation of the parison, the projections come into sealing contact with the exterior surface thereof so as to effectively prevent leakage of blow gas from the interior of the parison around the blow needle.
Claims14
A blow molding apparatus comprising:
- mold means which includes a pair of movable mold halves which are adapted to receive a parison in a cavity defined therebetween;
- blow means which includes a blow needle, having a longitudinal axis and a blow gas outlet end, which is adapted to puncture said parison with said gas outlet end and extend into the interior of said parison;
- sealing means which includes a plurality of generally concentric projections, each said projection completely surrounding said needle and having a first end, with inner and outer closed boundaries, and also a second end, wherein each said projection extends from said first end to said second end in a direction generally toward said cavity and generally parallel to said needle longitudinal axis, said sealing means being capable of assuming at least one position such that said projections extend into said cavity, whereby a parison can come into sealing contact with said projections at its exterior surface while said blow needle extends into the interior of said parison during blow molding thereof.
Dependencies are inferred from the claim text.