US3456739A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air hammer apparatus of a tuyere changing machine for a blast furnace
Assignee: IHI Corp
•
Filing: 1967-05-29
•
Granted: 1969-07-22
•
Expires: 1987-05-29
Abstract
No abstract record available.
Inventors
- 👤 Makoto Sagae
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:27
CPC Classifications
C; C21; C21B; C21B7/00; C21B7/16; C21B7/166; Y; Y10; Y10T; Y10T29/00; Y10T29/53; Y10T29/53796; Y10T29/53839
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1566631A
Cited
GB191505924A
Cited
US1665135A
Cited
US2561577A
Cited
US2641831A
Cited
US3136040A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-07-21 | 1973-01-20 | 1973-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-07-21 | 1977-01-20 | 1977-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-07-21 | 1981-01-20 | 1981-07-22 | $7700.00 | Window Closed / Lapsed |