Patent US2450234A successfully refreshed from Google Patents.
US4414008A
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Process for producing optical fiber preform
Assignee: Sumitomo Electric Industries Ltd
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Filing: 1981-12-11
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Granted: 1983-11-08
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Expires: 2001-12-11
Abstract
Abstract A process for producing a porous optical fiber preform by hydrolyzing a gaseous glass forming material with a flame from an oxyhydrogen burner and depositing the resulting soot in a rod form in a muffle furnace is described, wherein the muffle furnace is supplied with a gas other than that from the oxyhydrogen burner, and said gas is maintained at a constant temperature.
Inventors
- 👤 Takao Edahiro
- 👤 Tetsuo Miyajiri
- 👤 Hiroshi Yokota
- 👤 Toru Kuwahara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 03:19
CPC Classifications
C; C03; C03B; C03B37/00; C03B37/01; C03B37/012; C03B37/014; C03B37/0144
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
78 words
A process for producing a porous optical fiber preform by hydrolyzing a gaseous glass forming material with a flame from an oxyhydrogen burner and depositing the resulting soot in a rod form in a muffle furnace, wherein the muffle furnace is supplied with a preheated gas other than that from the oxyhydrogen burner, said preheated gas being air supplied at a constant temperature at a level slightly lower than the temperature of the gas within the muffle furnace.
Claim 2
Dependent Claim
78 words
A process for producing a porous optical fiber preform by hydrolyzing a gaseous glass forming material with a flame from an oxyhydrogen burner and depositing the resulting soot in a rod form in a muffle furnace, wherein the muffle furnace is supplied with a preheated gas other than that from the oxyhydrogen burner, said preheated gas being air supplied at a constant temperature at a level slightly lower than the temperature of the gas within the muffle furnace.
Claim 3
Dependent Claim
29 words
A processing according to claim 1, wherein said preheated air has a temperature less than 50° C. lower than the average temperature of the gas within the muffle furnace.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-11-07 | 1987-05-09 | 1987-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-11-07 | 1991-05-09 | 1991-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-11-07 | 1995-05-09 | 1995-11-08 | $7700.00 | Window Closed / Lapsed |