Patent US1938759A successfully refreshed from Google Patents.
Patent US5644746A successfully refreshed from Google Patents.
Patent US1290511A successfully refreshed from Google Patents.
Patent US2722433A successfully refreshed from Google Patents.
Patent US1729894A successfully refreshed from Google Patents.
US1729894A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Steel-derrick construction
Assignee: Individual
•
Filing: 1926-11-16
•
Granted: 1929-10-01
•
Expires: 1946-11-16
Abstract
No abstract record available.
Inventors
- 👤 Tracy S Park
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:26
CPC Classifications
E; E21; E21B; E21B15/00; Y; Y10; Y10T; Y10T403/00; Y10T403/71; Y10T403/7182
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) | 1932-09-30 | 1933-04-01 | 1933-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1936-09-30 | 1937-04-01 | 1937-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1940-09-30 | 1941-04-01 | 1941-10-01 | $7700.00 | Window Closed / Lapsed |