The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 10, 1999
Filed:
Oct. 01, 1997
Michae buttedl Blank, Wuppertal, DE;
Klaus Schramm, Essen, DE;
Fried Krupp AG Hoesch-Krupp, Essen and Dortmund, DE;
Abstract
A method of injection-molding three-layer moldings, especially bottle blanks, having inner and outer layers of a 'material A' and of a 'material B'. Material B can be a material that acts as a barrier against the gases O.sub.2, CO.sub.2, and SO.sub.2, and against water vapor (H.sub.2 O). The method employs a device that comprises at least one mold and at least one flat hot runner. The mold has several cavities and the hot runner has the same number of dies. Material A is supplied to the cavities (1.1) through an annular gap between the inner (2.1) and the outer (2.2) component of each die. Material B is forced into the cavities through a hollow needle (3) that extends through the center of the inner die component by a piston (4) that is integrated into the die and cannot rotate. The needle has a port (6) that opens into it at a right angle and remains open as long as the needle remains advanced, in a closing position, and that is blocked when the needle is retracted. A reservoir (3.3) constituted by the hollow inside the needle is charged through the port while the needle is in its closing position.