US3434957A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aluminum reduction cell with aluminum and refractory layered bottom construction
Assignee: Individual
•
Filing: 1966-02-18
•
Granted: 1969-03-25
•
Expires: 1986-02-18
Abstract
No abstract record available.
Inventors
- 👤 Arthur F Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 07:32
CPC Classifications
C; C25; C25C; C25C3/00; C25C3/06; C25C3/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
68 words
THE ELECTROLYTIC CELL FOR THE REDUCTION OF ALUMINUM COMPRISING A METAL SHELL HAVING RELATIVELY UPRIGHT SIDES, ENDS AND A GENERALLY FLAT BOTTOM, A SLAB OF SOLID ALUMINUM OR COPPER AT THE BOTTOM, A LAYER OF REFRACTORY THERMAL INSULATION OVER THE SOLID SLAB OF SUCH THICKNESS THAT IT IS AN EFFECTIVE HEAT BARRIER PREVENTING THE MELTING OF THE SOLID SLAB, A CARBON CATHODE VESSEL IN THE CELL HAVING A
Claim 2
Dependent Claim
68 words
THE ELECTROLYTIC CELL FOR THE REDUCTION OF ALUMINUM COMPRISING A METAL SHELL HAVING RELATIVELY UPRIGHT SIDES, ENDS AND A GENERALLY FLAT BOTTOM, A SLAB OF SOLID ALUMINUM OR COPPER AT THE BOTTOM, A LAYER OF REFRACTORY THERMAL INSULATION OVER THE SOLID SLAB OF SUCH THICKNESS THAT IT IS AN EFFECTIVE HEAT BARRIER PREVENTING THE MELTING OF THE SOLID SLAB, A CARBON CATHODE VESSEL IN THE CELL HAVING A
References Cited (Backward Citations)
US2378142A
Cited
US3202600A
Cited
US2971899A
Cited
US3161579A
Cited
US3257307A
Cited
US3321392A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-03-24 | 1972-09-23 | 1973-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-03-24 | 1976-09-23 | 1977-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-03-24 | 1980-09-23 | 1981-03-25 | $7700.00 | Window Closed / Lapsed |