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. 14, 1980
Filed:
Jun. 12, 1979
Emery J Hornyak, Jr, Temperance, MI (US);
Philip D Perry, Toledo, OH (US);
James E Sherman, Temperance, MI (US);
Owens-Illinois, Inc., Toledo, OH (US);
Abstract
Disclosed is a method and apparatus for preventing the formation of blisters in an electrically-heated forehearth that utilizes submerged electrodes connected to either a single or plural phase alternating current source. The electrodes are arranged so that Joule effect heating is effected by passing alternating current through the molten glass with the center tap of the secondary of the power transformer being connected to the positive side of a Direct Current source through a filter, while the negative side of the DC source is connected to a counter electrode, immersed in the glass at a point upstream of the forehearth. With this physical arrangement, the formation of blisters due to free electrons migrating to and collecting on some of the electrodes that are at different potentials than the others is prevented. This is accomplished by the fact that all of the forehearth electrodes are maintained at the same potential and the counter electrode is at a different potential so that these free electrons will collect at the single counter electrode and create bubbles or blisters at a position well in advance of the forehearth. With this system, the blisters will disappear before reaching the forehearth. The forehearth electrodes are disclosed as being formed of stainless steel with molybdenum tips and the electrode support being electrically isolated from the forehearth structure.