Patent US1712408A successfully refreshed from Google Patents.
Patent US3849679A successfully refreshed from Google Patents.
US3849679A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electroacoustic transducer with controlled beam pattern
Assignee: MASSA DONALD P COHASSET
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Filing: 1970-04-01
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Granted: 1974-11-19
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Expires: 1990-04-01
Abstract
Abstract A piezoelectric ceramic disc flexurally drives a thin vibratile diaphragm in its first overtone resonance mode. The center portion of the diaphragm has a displacement which is out of phase with respect to the displacement of the peripheral area of the diaphragm. A sound mask either precludes or selectively controls radiation from the center portion of the diaphragm.
Inventors
- 👤 F Massa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:30
CPC Classifications
G; G10; G10K; G10K9/00; G10K9/12; G10K9/122; H; H04; H04R; H04R17/00; H04R17/10
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
241 words
An electroacoustic transducer comprising a tubular housing open on at least one end, vibratile diaphragm means having a center portion and an outer peripheral portion, means for sealing the periphery of said vibratile diaphragm to close the open end of said tubular housing and form a clamped vibratile disc, transducer means comprising a piezoelectric disc rigidly bonded to one side of said diaphragm, electrical conductor means attached to said piezoelectric disc for imparting electrical signals thereto, the center and peripheral portions vibrating in different modes which give rise to alternative sonic effects depending upon the degree of interaction between said modes of vibration, and sound baffle means for controlling the radiation of sound from the center portion of said diaphragm as compared with the radiation of sound from the outer peripheral portion of said diaphragm, said vibratile diaphragm operating at its overtone resonant frequency mode of operation, wherein said means for controlling the sound radiating from the center portion comprises a rigid sound masking disc positioned over the center portion of said vibratile diaphragm and spaced away from the radiation surface thereof, the diameter of said sound masking disc being less than one-half the diameter of the free and unsupported portion of said vibratile disc, and the spacing between said sound masking disc and said vibratile diaphragm being a linear distance approximately equal to a number derived by dividing the area of said masking disc by the periphery of said disc.
Claim 2
Dependent Claim
241 words
An electroacoustic transducer comprising a tubular housing open on at least one end, vibratile diaphragm means having a center portion and an outer peripheral portion, means for sealing the periphery of said vibratile diaphragm to close the open end of said tubular housing and form a clamped vibratile disc, transducer means comprising a piezoelectric disc rigidly bonded to one side of said diaphragm, electrical conductor means attached to said piezoelectric disc for imparting electrical signals thereto, the center and peripheral portions vibrating in different modes which give rise to alternative sonic effects depending upon the degree of interaction between said modes of vibration, and sound baffle means for controlling the radiation of sound from the center portion of said diaphragm as compared with the radiation of sound from the outer peripheral portion of said diaphragm, said vibratile diaphragm operating at its overtone resonant frequency mode of operation, wherein said means for controlling the sound radiating from the center portion comprises a rigid sound masking disc positioned over the center portion of said vibratile diaphragm and spaced away from the radiation surface thereof, the diameter of said sound masking disc being less than one-half the diameter of the free and unsupported portion of said vibratile disc, and the spacing between said sound masking disc and said vibratile diaphragm being a linear distance approximately equal to a number derived by dividing the area of said masking disc by the periphery of said disc.
Claim 3
Dependent Claim
252 words
An electroacoustic transducer comprising a tubular housing open on at least one end, vibratile diaphragm means having a center portion and an outer peripheral portion, means for sealing the periphery of said vibratile diaphragm to close the open end of said tubular housing and form a clamped vibratile disc, transducer means comprising a piezoelectric disc rigidly bonded to one side of said diaphragm, electrical conductor means atTached to said piezoelectric disc for imparting electrical signals thereto, the center and peripheral portions vibrating in different modes which give rise to alternative sonic effects depending upon the degree of interaction between said modes of vibration, and sound baffle means for controlling the radiation of sound from the center portion of said diaphragm as compared with the radiation of sound from the outer peripheral portion of said diaphragm, said vibratile diaphragm operating at its overtone resonant frequency mode of operation, wherein said means for controlling the sound radiating from the center portion comprises a rigid sound masking disc positioned over the center portion of said vibratile diaphragm and spaced away from the radiating surface thereof, the diameter of said sound masking disc being less than one-half the diameter of the free and unsupported portion of said vibratile disc, said masking disc having a recess forming a cavity at its center portion on the side of the mask which faces said diaphragm, characterized in that there is a close spacing between the peripheral surface of said undercut disc and the opposing surface of said vibratile diaphragm.
Claim 4
Dependent Claim
252 words
An electroacoustic transducer comprising a tubular housing open on at least one end, vibratile diaphragm means having a center portion and an outer peripheral portion, means for sealing the periphery of said vibratile diaphragm to close the open end of said tubular housing and form a clamped vibratile disc, transducer means comprising a piezoelectric disc rigidly bonded to one side of said diaphragm, electrical conductor means atTached to said piezoelectric disc for imparting electrical signals thereto, the center and peripheral portions vibrating in different modes which give rise to alternative sonic effects depending upon the degree of interaction between said modes of vibration, and sound baffle means for controlling the radiation of sound from the center portion of said diaphragm as compared with the radiation of sound from the outer peripheral portion of said diaphragm, said vibratile diaphragm operating at its overtone resonant frequency mode of operation, wherein said means for controlling the sound radiating from the center portion comprises a rigid sound masking disc positioned over the center portion of said vibratile diaphragm and spaced away from the radiating surface thereof, the diameter of said sound masking disc being less than one-half the diameter of the free and unsupported portion of said vibratile disc, said masking disc having a recess forming a cavity at its center portion on the side of the mask which faces said diaphragm, characterized in that there is a close spacing between the peripheral surface of said undercut disc and the opposing surface of said vibratile diaphragm.
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) | 1977-11-18 | 1978-05-20 | 1978-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-18 | 1982-05-20 | 1982-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-18 | 1986-05-20 | 1986-11-19 | $7700.00 | Window Closed / Lapsed |