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:
Dec. 29, 1992
Filed:
Apr. 02, 1992
William D O'Brien, Jr, Lilburn, GA (US);
AT&T Bell Laboratories, Murray Hill, NJ (US);
Abstract
A preform tube (31) is caused to be collpased into a preform rod by causing a heat zone (54) provided by a torch assembly (50) to traverse the tube longitudinally in a plurality of passes. During this so-called collapse mode, a muffle tube (100) encloses that portion of the tube which extends through the torch assembly. Advantageously, the muffle tube projects a predetermined distance beyond one major face of the torch assembly. The torch assembly comprises annular semi-circular end plates and as annular semi-circular center portion having a plurality of exit ports through which gases are directed into engagement with the tube. The center portion is caused to be recessed between the end plates thereby causing the heat zone generated by the gases to be narrowed. The narrowing of the heat zone and the substantial confinement of the heat energy within the muffle tube cooperate with increased gas flow rates to cause the tube to be collapsed in a time period which is substantially less than that achieved by prior art methods.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile