Patent US470738A successfully refreshed from Google Patents.
US2311984A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Continuous rotary heat exchanger for catalyst systems
Assignee: Standard Oil Co
•
Filing: 1940-12-05
•
Granted: 1943-02-23
•
Expires: 1960-12-05
Abstract
No abstract record available.
Inventors
- 👤 Wilbur G Guild
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 13:16
CPC Classifications
B; B01; B01J; B01J8/00; B01J8/18; B01J8/1836; B01J8/08; B01J8/12; B01J2208/00; B01J2208/00008; B01J2208/00017; B01J2208/00106; B01J2208/00115; B01J2208/00132; B01J2208/0053
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1946-02-22 | 1946-08-24 | 1947-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1950-02-22 | 1950-08-24 | 1951-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1954-02-22 | 1954-08-24 | 1955-02-23 | $7700.00 | Window Closed / Lapsed |