초록 ▼

A method and apparatus for blow molding plastic articles which utilizes one or more fixed needles and one or more micro vents associated with a blow mold cavity. Each needle has a first passage associated therewith through which vacuum is supplied to pull the molten plastic about the needle and a se

A method and apparatus for blow molding plastic articles which utilizes one or more fixed needles and one or more micro vents associated with a blow mold cavity. Each needle has a first passage associated therewith through which vacuum is supplied to pull the molten plastic about the needle and a second passage therein through which air under pressure is introduced to tear the plastic and blow the article to the confines of the mold which has been closed about the plastic parison. Micro vents facilitate exhausting air which is about the parison. Preferably the second passage for compressed air is provided by a central bore and the first passage for the vacuum is provided by an annular space about the fixed needle. In a modified form, the fixed needle comprises dual air passages. Provision is made for utilizing plural molds with controls for supplying air and vacuum.

대표청구항 ▼

[ What is claimed is:] [1.] A method of blow molding hollow plastic containers comprising the steps of:providing a blow mold comprising mold portions which when closed define a mold cavity,providing a fixed blow needle in at least one mold portion, said blow needle having an opening,positioning a mo

[ What is claimed is:] [1.] A method of blow molding hollow plastic containers comprising the steps of:providing a blow mold comprising mold portions which when closed define a mold cavity,providing a fixed blow needle in at least one mold portion, said blow needle having an opening,positioning a molten hollow plastic parison between said mold portions,closing said mold portions about said plastic parison,providing fixed means in said one mold portion surrounding said fixed blow needle for pulling the molten plastic parison about the fixed blow needle,applying vacuum to the mold cavity through said fixed means to pull the molten plastic parison about the fixed blow needle, andthereafter providing air through the opening in said fixed needle to tear the plastic and to expand the parison to the confines of the mold cavity.