US3694677A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vhf-uhf piezoelectric resonators
Assignee: United States Department of the Army
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Filing: 1971-03-03
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Granted: 1972-09-26
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Expires: 1991-03-03
Abstract
Abstract This disclosure relates to crystals and particularly to very high frequency crystals. More particularly, this disclosure relates to techniques for increasing the fundamental resonant frequency of crystals beyond the limits of currently available mechanical techniques by reducing the thickness of a portion of the center of a standard crystal. This provides an effective resonant sector of an area and thickness that would be virtually impossible to manufacture or to mount by conventional techniques or use in existing mechanical structures.
Inventors
- 👤 Gunter K Guttwein
- 👤 Arthur D Ballato
- 👤 Theodore J Lukaszek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:32
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/15; H03H9/17; H03H9/177
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
26 words
A piezoelectric crystal as in claim 1 wherein one of said sides of said center portion is level with the corresponding side of said outer portion.
Claim 2
Dependent Claim
47 words
A piezoelectric crystal as in claim 1 wherein said one side of said center portion is below the level of the corresponding side of said outer portion, and said other side of said center portion is below the level of the corresponding side of said outer portion.
Claim 3
Dependent Claim
39 words
A piezoelectric crystal as in claim 1 wherein the diameter of said center portion is two-thirds of the diameter of said outer portion, and the thickness of said center portion is one-third of the thickness of said outer portion.
References Cited (Backward Citations)
US2498737A
Cited
US3363119A
Cited
US3382381A
Cited
US3396287A
Cited
US3569750A
Cited
US3576453A
Cited
US3585418A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-26 | 1976-03-27 | 1976-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-26 | 1980-03-27 | 1980-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-26 | 1984-03-27 | 1984-09-26 | $7700.00 | Window Closed / Lapsed |