US3521870A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Basic refractory monolith
Assignee: Dresser Industries Inc
•
Filing: 1969-05-16
•
Granted: 1970-07-28
•
Expires: 1989-05-16
Abstract
No abstract record available.
Inventors
- 👤 Thomas W Lewis
- 👤 George R Henry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 20:54
CPC Classifications
F; F27; F27D; F27D1/00; F27D1/0003; F27D1/0006; C; C04; C04B; C04B35/00; C04B35/01; C04B35/03; C04B35/04; C04B35/043; C04B35/047; C04B35/0473; C04B35/12; C04B35/42; C04B35/44; C21; C21C; C21C7/00; C21C7/10; F23; F23M; F23M5/00; F23M2700/00; F23M2700/005
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1973-07-27 | 1974-01-26 | 1974-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-07-27 | 1978-01-26 | 1978-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-07-27 | 1982-01-26 | 1982-07-28 | $7700.00 | Window Closed / Lapsed |