Patent US5149197A successfully refreshed from Google Patents.
US5149197A
Expired / Lapsed
US
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Piezo electric resonator temperature sensor
Assignee: Nortel Networks Ltd
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Filing: 1991-05-28
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Granted: 1992-09-22
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Expires: 2011-05-28
Abstract
Abstract The temperature of a quartz crystal oscillator is determined by comparison of a pair of inharmonically related overtone oxcillations of the same vibrational type, e.g. a thickness shear mode, and of the same overtone order. The use of inharmonically related signals relaxes the contraints on crystal design. The technique may be employed in a crystal controlled frequency synthesizer to provide a feedback signal for maintaining constant output frequency.
Inventors
- 👤 George H. S. Rokos
- 👤 Peter E. Morley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 05:12
CPC Classifications
G; G01; G01K; G01K7/00; G01K7/32
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
147 words
A method of determining the temperature of a crystal resonator comprising a lenticular quartz body, the method comprising providing a plurality of electrodes on said body, generating via said electrodes first and second harmonics of respective first and second C-mode fundamental vibrations, said first and second harmonics being mutually inharmonically related, of similar frequency and of the same overtone order, and comparing said first and second harmonics whereby to derive a signal indicative of the oscillator temperature, wherein each said harmonic fundamental vibration is a shear mode harmonic vibration characterised as an (n, a, b) vibration where n is the overtone number and is equal to the number of nodes along a first direction, a is the number of anti-nodes along a second direction perpendicular to the first direction, and b is the number of anti-nodes along a third direction perpendicular to said first and second direction.
Claim 2
Independent Claim
147 words
A method of determining the temperature of a crystal resonator comprising a lenticular quartz body, the method comprising providing a plurality of electrodes on said body, generating via said electrodes first and second harmonics of respective first and second C-mode fundamental vibrations, said first and second harmonics being mutually inharmonically related, of similar frequency and of the same overtone order, and comparing said first and second harmonics whereby to derive a signal indicative of the oscillator temperature, wherein each said harmonic fundamental vibration is a shear mode harmonic vibration characterised as an (n, a, b) vibration where n is the overtone number and is equal to the number of nodes along a first direction, a is the number of anti-nodes along a second direction perpendicular to the first direction, and b is the number of anti-nodes along a third direction perpendicular to said first and second direction.
Claim 3
Dependent Claim
26 words
A method as claimed in claim 1, wherein said first and second harmonics comprise respectively an (n, 1, 1) overtone and an (n, 1, 2) overtone.
Claim 4
Dependent Claim
26 words
A method as claimed in claim 1, wherein said first and second harmonics comprise respectively an (n, 2, 1) overtone and an (n, 2, 2) overtone.
Claim 5
Dependent Claim
24 words
A method as claimed in claim 1, wherein the crystal cut is selected from the group consisting of the SC, AT or BT cuts.
Claim 6
Dependent Claim
23 words
A method as claimed in claim 2, wherein said first and second harmonics are third harmonics for which n is equal to 3.
Claim 7
Dependent Claim
23 words
A method as claimed in claim 3, wherein said first and second harmonics are third harmonics for which n is equal to 3.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-09-22 | 1996-03-23 | 1996-09-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-09-22 | 2000-03-23 | 2000-09-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-09-22 | 2004-03-23 | 2004-09-22 | $7700.00 | Window Closed / Lapsed |