Patent US3022858A successfully refreshed from Google Patents.
US3022858A
Expired / Lapsed
US
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Apparatus and methods for production of helium by diffusion
Assignee: American Optical Corp
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Filing: 1959-09-25
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Granted: 1962-02-27
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Expires: 1979-09-25
Abstract
No abstract record available.
Inventors
- 👤 Edgar D Tillyer
- 👤 Willard E Folland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:37
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/22; B01D63/00; B01D63/06; C; C01; C01B; C01B23/00; B01D2313/00; B01D2313/18; B01D2319/00; B01D2319/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
26 words
A METHOD FOR EXTRACTING COMMERCIALLY PURE HELIUM FROM A MIXTURE OF GASES AND FOR MONITORING THE PURITY OF SAID HELIUM COMPRISING THE STEPS OF SEPARATING HELIUM
Claim 2
Independent Claim
26 words
A METHOD FOR EXTRACTING COMMERCIALLY PURE HELIUM FROM A MIXTURE OF GASES AND FOR MONITORING THE PURITY OF SAID HELIUM COMPRISING THE STEPS OF SEPARATING HELIUM
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) | 1965-02-26 | 1965-08-28 | 1966-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-02-26 | 1969-08-28 | 1970-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-02-26 | 1973-08-28 | 1974-02-27 | $7700.00 | Window Closed / Lapsed |