US3748502A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Piezoelectric helmholtz resonator for energy conversion
Assignee: Edo Corp
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Filing: 1971-08-04
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Granted: 1973-07-24
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Expires: 1991-08-04
Abstract
Abstract A Helmholtz resonator comprising an orifice and an otherwise enclosed volume includes one or more cascaded hollow piezoelectric cylinders. The resonator effects a conversion between an air flow and electrical energy, one energy form being applied as an input to excite the resonator and the other energy form being directly derivable as an output.
Inventors
- 👤 J Bernstein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 00:03
CPC Classifications
B; B06; B06B; B06B1/00; B06B1/02; B06B1/06; B06B1/0644; B06B1/0655
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
121 words
A Helmholtz resonator for converting between kinetic fluid energy and electrical energy, comprising first and second resonator end means and a Helmholtz resonator cavity therebetween, a hollow piezoelectric element disposed between said resonator end means and defining the side enclosure of said resonator cavity, first and second electrode means located respectively on the outer and inner surfaces of said hollow piezoelectric element, conductors connected to said electrodes, said first end means having an orifice therein, said second end means defining a cavity closure, and means for directing a fluid flow across said orifice, such that fluid flow across said orifice induces oscillations within the resonator cavity to induce periodic stress variations in the piezoelectric element and a voltage across said electrodes.
Claim 2
Dependent Claim
121 words
A Helmholtz resonator for converting between kinetic fluid energy and electrical energy, comprising first and second resonator end means and a Helmholtz resonator cavity therebetween, a hollow piezoelectric element disposed between said resonator end means and defining the side enclosure of said resonator cavity, first and second electrode means located respectively on the outer and inner surfaces of said hollow piezoelectric element, conductors connected to said electrodes, said first end means having an orifice therein, said second end means defining a cavity closure, and means for directing a fluid flow across said orifice, such that fluid flow across said orifice induces oscillations within the resonator cavity to induce periodic stress variations in the piezoelectric element and a voltage across said electrodes.
Claim 3
Dependent Claim
55 words
A combination as in claim 1 for arming an artillery projectile, further comprising an aperture located on the surface of said projectile such that a portion of the air flow past said aperture flows across said orifice, and circuitry connected to said conductors, said circuitry being activated when a voltage is induced across said conductors.
Claim 4
Dependent Claim
22 words
A combination as in claim 1, further comprising resilient insulating means spacing said piezoelectric element from said first and second end means.
Claim 5
Dependent Claim
28 words
A combination as in claim 1, wherein the orifice in said first end means has a cross-sectional area constricted from the cross-sectional area of said hollow piezoelectric element.
Claim 6
Dependent Claim
15 words
A combination as in claim 1 further comprising an electrical load connected to said conductors.
Claim 7
Dependent Claim
24 words
A combination as in claim 5 further comprising a rectifier and a low pass filter connected between one of said conductors and said load.
Claim 8
Dependent Claim
16 words
A combination as in claim 1 further comprising an inductance connected to one of said conductors.
Claim 9
Dependent Claim
32 words
A combination as in claim 7 wherein said resonator comprises a capacitive reactance at a natural resonance frequency, and wherein said inductance exhibits a substantially like absolute magnitude reactance at said frequency.
Claim 10
Dependent Claim
19 words
A combination as in claim 1 wherein said piezoelectric member comprises a plurality of hollow piezoelectric segments adhered together.
References Cited (Backward Citations)
US3150592A
Cited
US3215078A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-23 | 1977-01-22 | 1977-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-23 | 1981-01-22 | 1981-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-23 | 1985-01-22 | 1985-07-24 | $7700.00 | Window Closed / Lapsed |