Patent US3570456A successfully refreshed from Google Patents.
Patent US3372351A successfully refreshed from Google Patents.
US3372351A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mechanically strong mechanical resonant filter having weak coupling between resonators
Assignee: Telefunken Patentverwertungs GmbH
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Filing: 1964-01-20
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Granted: 1968-03-05
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Expires: 1984-01-20
Abstract
No abstract record available.
Inventors
- 👤 Borner Manfred
- 👤 Schussler Hans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:22
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/46; H03H9/48; H03H9/50
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
90 words
A MECHANICAL RESONANT FILTER DEVICE HAVING A SMALL RELATIVE BANDWIDTH COMPRISING, IN COMBINATION: AT LEAST TWO MECHANICAL RESONANT BODIES; AND HOMOGENEOUS COUPLING LINE MEANS FOR DIRECTLY CONNECTING SAID RESONANT BODIES, SAID COUPLING MEANS INCLUDING AT LEAST TWO COUPLING LINES CONNECTED FOR COUPLING OSCILLATIONS WHICH ARE ONLY APPROXIMATELY 180* PHASE-SHIFTED WITH RESPECT TO EACH OTHER IN THE PASS WAVE RANGE FOR REDUCING THE COUPLING FACTOR, SAID COUPLING LINES HAVING AN ACOUSTICAL LENGTH OF (2N+1)$/4, WHERE $=WAVELENGTH AT THE CENTER FREQUENCY OF THE COUPLING LINE AND N IS EQUAL TO AN INTEGER.
Claim 2
Dependent Claim
90 words
A MECHANICAL RESONANT FILTER DEVICE HAVING A SMALL RELATIVE BANDWIDTH COMPRISING, IN COMBINATION: AT LEAST TWO MECHANICAL RESONANT BODIES; AND HOMOGENEOUS COUPLING LINE MEANS FOR DIRECTLY CONNECTING SAID RESONANT BODIES, SAID COUPLING MEANS INCLUDING AT LEAST TWO COUPLING LINES CONNECTED FOR COUPLING OSCILLATIONS WHICH ARE ONLY APPROXIMATELY 180* PHASE-SHIFTED WITH RESPECT TO EACH OTHER IN THE PASS WAVE RANGE FOR REDUCING THE COUPLING FACTOR, SAID COUPLING LINES HAVING AN ACOUSTICAL LENGTH OF (2N+1)$/4, WHERE $=WAVELENGTH AT THE CENTER FREQUENCY OF THE COUPLING LINE AND N IS EQUAL TO AN INTEGER.
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) | 1971-03-05 | 1971-09-04 | 1972-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-03-05 | 1975-09-04 | 1976-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-03-05 | 1979-09-04 | 1980-03-05 | $7700.00 | Window Closed / Lapsed |