Patent US5153476A successfully refreshed from Google Patents.
US5153476A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acoustic vibrator with variable sensitivity to external acceleration
Assignee: United States Department of the Army
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Filing: 1991-03-11
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Granted: 1992-10-06
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Expires: 2011-03-11
Abstract
Abstract Biasing electrodes on a piezoelectric acoustic vibrator alter the sensitivity of the acoustic vibrator and can be used to compensate for external stresses applied to the acoustic vibrator. The biasing electrodes and the circuitry providing electric signals to them are separate from the RF circuitry feeding the RF signal electrodes of the acoustic vibrator. Biasing electrodes can be used on bulk acoustic wave devices or surface acoustic wave devices. The biasing electrodes can be energized by a static D.C. voltage source, or can be used in a dynamic biasing arrangement to provide instantaneous compensation for changing environmental conditions.
Inventors
- 👤 John A. Kosinski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:20
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/15; H03H9/17; H03H9/177; G; G01; G01P; G01P15/00; G01P15/02; G01P15/08; G01P15/097; G01P15/0975; H03H9/02; H03H9/02007; H03H9/02086; H03H9/02133; H03H9/02228; H03H9/02535; H03H9/02818; H03H9/125; H03H9/145; H03H9/25
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
172 words
An acoustic vibrator subject to external stresses comprising: a substrate; first electrode means arranged on said substrate for creating a mechanical mode shape of said substrate, said mechanical mode shape having a predetermined characteristic frequency in the absence of external stresses, said first electrode means being electrically connected to a first external means for supplying a first group of signals; and second electrode means electrically connected to a second external means for supplying a second group of signals, said first and second external means being separate from each other, said second electrode means arranged on said substrate for generating bias stresses by application of electrical bias signals, said second electrode means being arranged around the first electrode means such that said electrical bias signals do not effect said mechanical mode shape, said second electrode means arranged to detect external stress on said substrate and adjust said biasing signals in response thereto; wherein frequency perturbations caused by external stresses are compensated for by said electrical bias voltages applied to said second electrode means.
Claim 2
Dependent Claim
172 words
An acoustic vibrator subject to external stresses comprising: a substrate; first electrode means arranged on said substrate for creating a mechanical mode shape of said substrate, said mechanical mode shape having a predetermined characteristic frequency in the absence of external stresses, said first electrode means being electrically connected to a first external means for supplying a first group of signals; and second electrode means electrically connected to a second external means for supplying a second group of signals, said first and second external means being separate from each other, said second electrode means arranged on said substrate for generating bias stresses by application of electrical bias signals, said second electrode means being arranged around the first electrode means such that said electrical bias signals do not effect said mechanical mode shape, said second electrode means arranged to detect external stress on said substrate and adjust said biasing signals in response thereto; wherein frequency perturbations caused by external stresses are compensated for by said electrical bias voltages applied to said second electrode means.
Claim 3
Dependent Claim
12 words
The acoustic vibrator of claim 1 wherein said substrate comprises piezoelectric material.
Claim 4
Dependent Claim
15 words
The acoustic vibrator of claim 2 wherein said first group of signals comprises RF signals.
Claim 5
Dependent Claim
16 words
The acoustic vibrator of claim 3 wherein said second group of signals comprise DC bias signals.
Claim 6
Dependent Claim
55 words
The acoustic vibrator of claim 4, wherein said second external means comprises at least one independently adjustable DC source, and said second electrode means for generating bias stresses comprises. a plurality of bias electrodes arranged on said substrate in a predetermined manner, each said bias electrode being connected to a single independently adjustable DC source.
Claim 7
Dependent Claim
23 words
The acoustic vibrator of claim 5, wherein said bias electrodes are arranged to provide stress bias along at least two mutually orthogonal lines.
Claim 8
Dependent Claim
16 words
The acoustic vibrator of claim 3 wherein said second group of signals comprise AC biasing signals.
Claim 9
Dependent Claim
14 words
The acoustic vibrator of claim 7, wherein said AC biasing signals are dynamically adjusted.
Claim 10
Dependent Claim
25 words
The acoustic vibrator of claim 8 wherein said second electrode means for generating bias stresses comprises a plurality of interdigitated electrodes arranged on said substrate.
Claim 11
Dependent Claim
23 words
The acoustic vibrator of claim 9 wherein said interdigitated electrodes are arranged to provide stress bias along at least two mutually orthogonal lines.
Claim 12
Dependent Claim
28 words
The acoustic vibrator of claim 1 wherein said substrate and said first electrode means for creating a mechanical mode pattern are arranged as a bulk acoustic wave device.
Claim 13
Dependent Claim
28 words
The acoustic vibrator of claim 1 wherein said substrate and said first electrode means for creating a mechanical mode pattern are arranged as a surface acoustic wave device.
Claim 14
Dependent Claim
60 words
The acoustic vibrator of claim 12 wherein said substrate further comprises first and second major surfaces, each having a periphery, wherein said first electrode means for creating a mechanical mode shape are arranged on said first major surface of said substrate and said second electrode means for generating bias stress are arranged on said first major surface of said substrate.
Claim 15
Dependent Claim
28 words
The acoustic vibrator of claim 13 wherein said second electrode means for generating bias stress are arranged along the periphery of said first major surface of said substrate.
Claim 16
Dependent Claim
60 words
The acoustic vibrator of claim 12 wherein said substrate further comprises first and second major surfaces, each having a periphery, wherein said first electrode means for creating a mechanical mode shape are arranged on said first major surface of said substrate and said second electrode means for generating bias stress are arranged on said second major surface of said substrate.
Claim 17
Dependent Claim
28 words
The acoustic vibrator of claim 15 wherein said second electrode means for generating bias stresses is arranged along the periphery of said second major surface of said substrate.
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| 3.5 Years (Year 4) | 1995-10-06 | 1996-04-06 | 1996-10-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-10-06 | 2000-04-06 | 2000-10-06 | $3760.00 | Window Closed / Lapsed |
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