US3708702A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electroacoustic transducer
Assignee: Siemens AG
•
Filing: 1970-12-02
•
Granted: 1973-01-02
•
Expires: 1990-12-02
Abstract
Abstract An electroacoustic transducer is described which is especially useful in telephones. An essentially flat frequency response curve in the voice range is realized by setting up a resonance peak in the free section of the diaphragm. The diaphragm is supported at its periphery by elastic bodies so that the fundamental frequency of oscillation of the diaphragm will have a node line in the region where the diaphragm is supported. The support arrangement according to the invention sets up at least a second node line having a smaller diameter than the fundamental node line and in the free section of the diaphragm.
Inventors
- 👤 O Brunnert
- 👤 H Schierl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:40
CPC Classifications
H; H04; H04R; H04R7/00; H04R7/16; H04R7/18
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
142 words
An electroacoustic transducer, comprising: a diaphragm constructed from electrostrictive material and means for supporting said diaphragm around the periphery thereof constructed of elastic material, said supporting means, in order to engage said diaphragm on both sides thereof, having at least an opposed pair of projections extending inwardly of said supporting means and around the perimeter thereof, the portions of said supporting means engaging said diaphragm on both sides thereof having corresponding elastic characteristics, whereby a resonance peak corresponding to the fundamental frequency of oscillation of said diaphragm, in the desired frequency range of operation of said transducer, and at least one additional resonance peak are set up, said additional resonance peak having a node line in the free section of said diaphragm and being at a frequency which is in the frequency bandwidth in which it is desired that said transducer operate.
Claim 2
Dependent Claim
142 words
An electroacoustic transducer, comprising: a diaphragm constructed from electrostrictive material and means for supporting said diaphragm around the periphery thereof constructed of elastic material, said supporting means, in order to engage said diaphragm on both sides thereof, having at least an opposed pair of projections extending inwardly of said supporting means and around the perimeter thereof, the portions of said supporting means engaging said diaphragm on both sides thereof having corresponding elastic characteristics, whereby a resonance peak corresponding to the fundamental frequency of oscillation of said diaphragm, in the desired frequency range of operation of said transducer, and at least one additional resonance peak are set up, said additional resonance peak having a node line in the free section of said diaphragm and being at a frequency which is in the frequency bandwidth in which it is desired that said transducer operate.
Claim 3
Dependent Claim
17 words
The electroacoustic transducer defined in claim 1 wherein said diaphragm is stressed to the point of bending.
Claim 4
Dependent Claim
14 words
The electroacoustic transducer defined in claim 1 wherein said elastic material is silicon rubber.
Claim 5
Dependent Claim
43 words
The electroacoustic transducer defined in claim 1 wherein said diaphragm is placed in said supporting means so that the edge area of said diaphragm which vibrates in a plane perpendicular to the surface plane of the diaphragm is free of said supporting means.
Claim 6
Dependent Claim
56 words
The electroacoustic transducer defined in claim 1 wherein said supporting means comprises at least two opposed pairs of said projections having a shape substantially corresponding to the peripheral shape of said diaphragm and wherein the radially outermost of said projections surround a surface area of said diaphragm smaller than the total surface area of said diaphragm.
Claim 7
Dependent Claim
38 words
The electroacoustic transducer defined in claim 5 wherein said supporting means has portions removed from its cross sectional area so that the portions of said supporting means having a smaller cross sectional area are vertically adjacent said projections.
Claim 8
Dependent Claim
16 words
The electroacoustic transducer defined in claim 1 wherein said projections have a trapezoidal cross sectional shape.
Claim 9
Dependent Claim
18 words
The electroacoustic transducer defined in claim 1 wherein said diaphragm includes at least a layer of piezoelectric material.
References Cited (Backward Citations)
US3137836A
Cited
US3085167A
Cited
US3166730A
Cited
US3222462A
Cited
US3297968A
Cited
US3331970A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-01-02 | 1976-07-03 | 1977-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-02 | 1980-07-03 | 1981-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-02 | 1984-07-03 | 1985-01-02 | $7700.00 | Window Closed / Lapsed |