US3522724A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for testing clean room filtration efficiency
Assignee: Kidde Inc
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Filing: 1968-03-29
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Granted: 1970-08-04
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Expires: 1988-03-29
Abstract
No abstract record available.
Inventors
- 👤 James V Knab
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:28
CPC Classifications
G; G01; G01M; G01M3/00; G01M3/02; G01M3/04; G01M3/20; F; F24; F24F; F24F13/00; F24F13/08; F24F13/10; F24F13/14; F24F13/1413; F24F13/1426; F24F3/00; F24F3/12; F24F3/16; F24F3/167; F24F2013/1473
Claims Analysis
Total Claims: 0
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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) | 1973-08-03 | 1974-02-02 | 1974-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-08-03 | 1978-02-02 | 1978-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-08-03 | 1982-02-02 | 1982-08-04 | $7700.00 | Window Closed / Lapsed |