US3700938A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electroacoustic transducer with magnetic transducing element clamping
Assignee: AT&T Inc
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Filing: 1971-12-15
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Granted: 1972-10-24
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Expires: 1991-12-15
Abstract
Abstract An electromechanical transducing element is bonded to a magnetic plate, and the composite structure is clamped within a transducer housing by means of one or more magnets attached thereto or embedded therein. The magnets serve to semirigidly clamp the plate to the housing, obviating the need for cement or other rigid clamping means, thereby reducing undesirable high or nonuniform stresses in the plate and allowing radial expansion and contraction of the plate due to thermal variations without damage to the transducer or alteration of its performance.
Inventors
- 👤 Herbert William Bryant
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:57
CPC Classifications
H; H04; H04R; H04R7/00; H04R7/16; H04R7/18; H04R7/22
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
42 words
An electroacoustic transducer comprising an electromechanical transducing element, a housing defining an internal chamber for containing said element, a diaphragm of magnetic material for supporting said element, and at least one magnet for clamping said diaphragm to said housing within said chamber.
Claim 2
Dependent Claim
42 words
An electroacoustic transducer comprising an electromechanical transducing element, a housing defining an internal chamber for containing said element, a diaphragm of magnetic material for supporting said element, and at least one magnet for clamping said diaphragm to said housing within said chamber.
Claim 3
Dependent Claim
27 words
The invention defined in claim 1 wherein said housing includes an inwardly extending lip for supporting said diaphragm and wherein said magnet is imbedded within said lip.
Claim 4
Dependent Claim
23 words
The invention defined in claim 2 wherein said lip is generally circular and wherein three magnets are spaced substantially equally around said lip.
Claim 5
Dependent Claim
12 words
The invention defined in claim 3 wherein said transducing element is rectangular.
Claim 6
Dependent Claim
16 words
The invention defined in claim 4 wherein said transducing element comprises a poled ferroelectric ceramic material.
Claim 7
Dependent Claim
26 words
The invention defined in claim 5 wherein said ceramic material is selected from the group consisting of barium titanate, lead zirconate-lead titanate, and sodium potassium niobate.
Claim 8
Dependent Claim
55 words
The invention defined in claim 1 wherein said housing includes a cup-shaped member having sidewalls, a bottom wall, and an inwardly extending lip around said sidewall for supporting said diaphragm in spaced relation from said bottom, and said magnet is fastened to said bottom wall and arranged to exert an attractive force on said diaphragm.
Claim 9
Dependent Claim
49 words
An electroacoustic transducer comprising an electromechanical transducing element, a housing defining an internal chamber for containing said element, a magnetic diaphragm for supporting said element, an inwardly extending lip within said chamber of said housing for supporting said diaphragm, and magnetic means for clamping said diaphragm to said lip.
Claim 10
Dependent Claim
49 words
An electroacoustic transducer comprising an electromechanical transducing element, a housing defining an internal chamber for containing said element, a magnetic diaphragm for supporting said element, an inwardly extending lip within said chamber of said housing for supporting said diaphragm, and magnetic means for clamping said diaphragm to said lip.
Claim 11
Dependent Claim
19 words
The invention defined in claim 8 wherein said magnetic means includes at least one magnet imbedded within said lip.
Claim 12
Dependent Claim
28 words
The invention defined in claim 8 wherein said lip is generally circular, and said magnetic means includes three magnets spaced substantially equally around the periphery of said lip.
Claim 13
Dependent Claim
23 words
The invention defined in claim 10 wherein said transducer further includes a magnetic ring atop said diaphragm for increasing the diaphragm clamping force.
Claim 14
Dependent Claim
34 words
The invention defined in claim 8 wherein said housing includes an inner bottom wall, and said magnetic means is fastened to said bottom wall and arranged to exert an attractive force on said diaphragm.
References Cited (Backward Citations)
US1886815A
Cited
US3120622A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-24 | 1976-04-24 | 1976-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-24 | 1980-04-24 | 1980-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-24 | 1984-04-24 | 1984-10-24 | $7700.00 | Window Closed / Lapsed |