US3883340A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Glass melting method
Assignee: AT&T Inc
•
Filing: 1973-03-29
•
Granted: 1975-05-13
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Expires: 1993-03-29
Abstract
Abstract The disclosed glass melting method makes use of an apparatus incorporating a skirted lid fixed to a stirring rod with a hollow stem. The lid fits over the melt container leaving a limited space between the lid and the container. The continual introduction of a gas into the container through the hollow stem of the stirring rod allows control of the atmosphere over the melt during the homogenization and conditioning steps in the formation of the glass. The continual outflow of gas between the container and the lid skirt reduces the possibility of contamination of the melt from the furnace atmosphere.
Inventors
- 👤 William George French
- 👤 Arthur David Pearson
- 👤 Arthur Richard Tynes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:11
CPC Classifications
C; C03; C03B; C03B5/00; C03B5/16; C03B5/18; C03B5/187
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
196 words
A method for the production of glass comprising; a. melting the constituents in a crucible to form a melt, b. maintaining the melt at an elevated temperature with a controlled atmosphere above the melt, the crucible being situated in a furnace, c. stirring the melt and d. cooling the melt characterized in that the controlled atmosphere is isolated from the furnace by the continual introduction of filtered gas of controlled composition into a partially enclosed chamber above the melt so that an outwardly flowing gas stream of linear velocity at least 10 feet per minute is maintained through a corridor at least one quarter of an inch long between the enclosed chamber and the furnace whereby the flow of contaminants from the furnace into the enclosed chamber is inhibited wherein the partially enclosed chamber and corridor are formed by suspending a skirted lid above the crucible, which skirted lid has an inner diameter more than one percent larger than the outer diameter of the crucible and which skirted lid is suspended by means of a hollow tube extending through the lid, which hollow tube additionally serves to introduce the filtered gas into the partially enclosed chamber.
Claim 2
Independent Claim
196 words
A method for the production of glass comprising; a. melting the constituents in a crucible to form a melt, b. maintaining the melt at an elevated temperature with a controlled atmosphere above the melt, the crucible being situated in a furnace, c. stirring the melt and d. cooling the melt characterized in that the controlled atmosphere is isolated from the furnace by the continual introduction of filtered gas of controlled composition into a partially enclosed chamber above the melt so that an outwardly flowing gas stream of linear velocity at least 10 feet per minute is maintained through a corridor at least one quarter of an inch long between the enclosed chamber and the furnace whereby the flow of contaminants from the furnace into the enclosed chamber is inhibited wherein the partially enclosed chamber and corridor are formed by suspending a skirted lid above the crucible, which skirted lid has an inner diameter more than one percent larger than the outer diameter of the crucible and which skirted lid is suspended by means of a hollow tube extending through the lid, which hollow tube additionally serves to introduce the filtered gas into the partially enclosed chamber.
Claim 3
Dependent Claim
20 words
A method of claim 1 in which the hollow tube is terminated at its lower end by a stirring member.
Claim 4
Dependent Claim
21 words
A method of claim 1 in which the gas stream has a linear velocity of at least 50 feet per minute.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-12 | 1978-11-11 | 1979-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-12 | 1982-11-11 | 1983-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-12 | 1986-11-11 | 1987-05-13 | $7700.00 | Window Closed / Lapsed |