US2581007A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Swimming helmet
Assignee: Individual
•
Filing: 1947-01-11
•
Granted: 1952-01-01
•
Expires: 1967-01-11
Abstract
No abstract record available.
Inventors
- 👤 Donald J Douglas
- 👤 Russell L Douglas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 01:19
CPC Classifications
A; A63; A63B; A63B33/00; A42; A42B; A42B1/00; A42B1/04; A42B1/12; A63B33/002; F; F16; F16K; F16K15/00; F16K15/14; F16K15/1401; F16K15/148; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7837; Y10T137/7838; Y10T137/7879; Y10T137/7888; Y10T137/789; Y10T137/7904; Y10T137/7922; Y10T137/7929
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US645408A
Cited
GB191212142A
Cited
US1433676A
Cited
US1501591A
Cited
US1483226A
Cited
CH183068A
Cited
US2063232A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-12-31 | 1955-07-02 | 1956-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-12-31 | 1959-07-02 | 1960-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-12-31 | 1963-07-02 | 1964-01-01 | $7700.00 | Window Closed / Lapsed |