Method and device for producing preforms with special geometries
AssigneeNetstal-Maschinen AG
InventorsStefan Bock, Britta Scheunemann
Life of this patent
Estimating the term…
Abstract
Preforms with a neck region and a preform body and having an enlarged geometry in comparison with the cavity of the injection mold are produced by injecting a polymer melt into the mold with a geometry of the cavity in the mold such that the radial extent of an inner space in the preform body thereby produced is not greater than the radial extent of the inner space in the neck region, the preforms are removed from the open mold by a removal gripper, and the preforms in the removal gripper are inflated using positive pressure such that the geometry of the inflated preform body is larger than the cavity in the injection mold.
Claims16
A method for producing a preform, comprising:
- injecting a polymer melt into an injection mould having a cavity shaped to mold a preform formed with a neck region and defined by an inner space having in a preform body region a radial extent which is not greater than a radial extent of the inner space in the neck region adjacent the preform body region;
- opening the injection mould after a first cooling step;
- removing the preform from the open mould with a removal gripper;
- and
- inflating the preform relative to the cavity of the injection mould with use of a positive pressure so that the preform increases relative to the cavity of the injection mould and a wall of the inflated preform is urged against a wall of a cavity of the removal gripper, said cavity of the removal gripper sized greater in a base region of the preform than the cavity of the injection mould,
- wherein said inflating step includes inflating the base region of the preform in the removal gripper with the positive pressure in a range between 0.5 and 8 bar.
A method for producing a preform, comprising:
- injecting a polymer melt into an injection mould having a cavity shaped to mold a preform formed with a neck region and defined by an inner space having in a preform body region a radial extent which is not greater than a radial extent of the inner space in the neck region adjacent the preform body region;
- opening the injection mould after a first cooling step;
- removing the preform from the open mould with a removal gripper;
- inflating the preform relative to the cavity of the injection mould with use of a positive pressure so that the preform increases relative to the cavity of the injection mould and a wall of the inflated preform is urged against a wall of a cavity of the removal gripper, said cavity of the removal gripper sized greater in a base region of the preform than the cavity of the injection mould, and
- tempering a removal sleeve of the removal gripper to condition the preform at a temperature range between 90° and 150° C.
Dependencies are inferred from the claim text.