US3846779A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ultrasonic transducer
Assignee: Individual
•
Filing: 1972-08-28
•
Granted: 1974-11-05
•
Expires: 1992-08-28
Abstract
Abstract 1. IN AN ALARM DEVICE FOR DETECTING VARIATIONS IN ULTRASONIC SIGNALS AND ACTIVATING AN ALARM, A TRANSDUCER FOR TRANSMITTING OR RECEIVING ULTRASONIC SIGNALS IS AN AIR ENVIRONMENT COMPRISING A PIEZOELECTRIC ELEMENT COUPLED TO A THIN FLAT PLATE WHICH IS SUBSTANTIALLY LARGER THAN SAID PIEZOELECTRIC ELEMENT AND WHICH HAS A PERIPHERY MAINTAINED SUBSTANTIALLY FREE AND UNSUPPORTED DURING OPERATION, SAID PIEZOELECTRIC ELEMENT HAVING A RESONANT FREQUENCY AT WHICH IT IS EXICITABLE AND SAID FLAT PLATE HAVING A RESONANT FREQUENCY WHEN COUPLED TO SAID ELEMENT SUBSTANTIALLY EQUAL TO THE RESONANT FREQUENCY OF THE PIEZOELECTRIC ELEMENT. D R A W I N G
Inventors
- 👤 J Martner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 02:54
CPC Classifications
B; B06; B06B; B06B1/00; B06B1/02; B06B1/06; B06B1/0644; B06B1/0648; G; G08; G08B; G08B13/00; G08B13/16; G08B13/1609
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) | 1977-11-04 | 1978-05-06 | 1978-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-04 | 1982-05-06 | 1982-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-04 | 1986-05-06 | 1986-11-05 | $7700.00 | Window Closed / Lapsed |