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US3474400A
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Sonic presence detection system and method
Assignee: SPX Technologies Inc
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Filing: 1967-04-07
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Granted: 1969-10-21
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Expires: 1987-04-07
Abstract
No abstract record available.
Inventors
- 👤 John H Auer Jr
- 👤 Jerry P Huffman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:03
CPC Classifications
G; G08; G08G; G08G1/00; G08G1/01; G08G1/04; G01; G01S; G01S1/00; G01S1/72; G01S15/00; G01S15/02; G01S15/04; G01S15/06; G01S15/08; G01S15/10; G01S15/18; G01S7/00; G01S7/52; G01S7/523; G01S7/526; G01S7/527; G01S7/529; Y; Y10; Y10S; Y10S367/00; Y10S367/903
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) | 1972-10-20 | 1973-04-21 | 1973-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-10-20 | 1977-04-21 | 1977-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-10-20 | 1981-04-21 | 1981-10-21 | $7700.00 | Window Closed / Lapsed |