US3540472A
Expired / Lapsed
US
⏱️ 0.0 years remaining
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Assignee: Individual
•
Filing: 1967-07-13
•
Granted: 1970-11-17
•
Expires: 1987-07-13
Abstract
No abstract record available.
Inventors
- 👤 Richard F Brady
- 👤 Jean C Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:24
CPC Classifications
F; F16; F16K; F16K15/00; F16K15/02; F16K15/06; F16K17/00; F16K17/02; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7837; Y10T137/7866; Y10T137/7867; Y10T137/7868; Y10T137/7904; Y10T137/7908; Y10T137/7909; Y10T137/7913; Y10T137/7915
Claims Analysis
Total Claims: 0
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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) | 1973-11-16 | 1974-05-18 | 1974-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-11-16 | 1978-05-18 | 1978-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-11-16 | 1982-05-18 | 1982-11-17 | $7700.00 | Window Closed / Lapsed |