US 5,085,822 A · Method for stretch blow molding and uniformly cooling a hollow heat-resistant

Abstract

A method for stretch blow molding a preform into a hollow container having a heat-resistant property, including the steps of heat setting the hollow container by maintaining the hollow container heated for a predetermined period of time within a blow mold and cooling the hollow container by the use of a cooling medium blown out from the forward end of a stretching rod at least during backward movement of the stretching rod. If the heat setting operation is to be performed in a heat setting mold separately of the blow mold, the hollow container is cooled by the cooling medium blown out from the forward end of a cooling medium introducing rod while being moved. Since the cooling medium outlet is axially moved, the hollow container can be cooled uniformly, even if the hollow container has a particularly increased rate of longitudinal stretch. If a cooling medium introducing tube for introducing the cooling medium along the central axis of the rod is thermally insulated, any sweating and/or freezing on the rod can be prevented.

Claims8

Dependent claims

A method for stretch blow molding a preform into a hollow container having a heat-resistant property, comprising the steps of:

positioning the preform in place within a heated blow mold;
biaxially stretching and blow molding said preform into said hollow container by longitudinally stretching said preform under the action of a stretching rod moved forwardly while causing a forward end of said stretching rod to engage the internal bottom of said preform and by transversely stretching said preform under the action of blowing fluid blown out from a blow core located within the neck portion of said preform;
holding said hollow container within said blow mold under a blowing pressure and heat setting said hollow container by maintaining said hollow container heated for a predetermined period of time;
cooling said hollow container, which has been heat set, by a cooling medium blown out from the forward end of said stretching rod at least during backward movement of said stretching rod away from the internal bottom of said reform;, and
thereafter removing said hollow container from said blow mold.

2 more elements

A method for stretch blow molding a preform into a hollow container having a heat-resistant property, comprising the steps of:

positioning the preform in place within a blow mold;
biaxially stretching and blow molding said preform into said hollow container by longitudinally stretching said preform under the action of a stretching rod moved forwardly while causing a forward end of said stretching rod to engage the internal bottom of said preform and by transversely stretching said preform under the action of blowing fluid blown out from a blow core located within the neck portion of said preform.
transferring the hollow container from said blow mold into a heated heat setting mold after the hollow container has been subjected to the biaxially stretching and blow molding step in said blow mold and then maintaining the hollow container heated for a predetermined period of time to heat set the hollow container;
then cooling the hollow container by a cooling medium blown out from the forward end of a cooling medium introducing rod put into said hollow container through the neck portion of said hollow container while moving said cooling medium introducing rod in the longitudinal axial direction within the interior of the hollow container;
and
thereafter removing the hollow container out of said blow mold.

3 more elements

Dependencies are inferred from the claim text.

Method for stretch blow molding and uniformly cooling a hollow heat-resistant

Life of this patent

Method for stretch blow molding and uniformly cooling a hollow heat-resistant

Life of this patent

Abstract

Claims8