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:
Oct. 20, 1981
Filed:
Apr. 12, 1979
Donald G Trutner, Chatham, NJ (US);
Luke Thorington, Easton, PA (US);
Duro-Test Corporation, N. Bergen, NJ (US);
Abstract
A method and apparatus for reworking hollow workpieces, illustratively glass lamp bulbs, to a desired dimensional accuracy and optical finish. In the method, a workpiece is placed within a mold having a cavity which defines the desired dimensions. Molten metal, preferably tin, of temperature sufficient to soften the workpiece is introduced into the hollow interior of the workpiece. The static pressure of the molten metal forces the softened workpiece into contact with the interior surface of the mold thereby imparting to the workpiece the desired dimensions. Molten metal of lower temperature is then introduced into the workpiece from a lower interior portion thereof, displacing the molten metal of high temperature out of the workpiece. The newly introduced molten metal cools the workpiece so that it may be handled without deforming. The molten metal is then removed from the interior of the workpiece and the workpiece is removed from the mold. The method may advantageously be employed in a nonoxidizing environment, such as one of nitrogen gas. In the apparatus, first and second mold portions have interior portions which align to define a mold cavity. The mold portions are laterally separated to receive a workpiece within the mold cavity. A reservoir supplies heated fluid to the interior of the hollow workpiece. The mold portions and contained workpiece are downwardly rotated to decant fluid from the interior of the workpiece.