Patent US4409441A successfully refreshed from Google Patents.
US4409441A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ultrasonic transducer for use in a vibratory environment
Assignee: Polaroid Corp
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Filing: 1981-07-02
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Granted: 1983-10-11
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Expires: 2001-07-02
Abstract
Abstract A capacitance-type electrostatic transducer is provided that can be operated in an environment where it may be subjected to excessive mechanical vibrations. Unwanted gain variations and/or spurious electrical signals produced by said transducer when operated in such an environment are precluded by preventing relative movement between the spring that urges the backplate into cooperative engagement with the vibratile diaphragm of the transducer and said transducer backplate, at the point of contact between said spring and said backplate.
Inventors
- 👤 Joseph E. Murray, Jr.
- 👤 Paul J. Sylvester
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 01:33
CPC Classifications
G; G01; G01H; G01H11/00; G01H11/06; H; H04; H04R; H04R19/00
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
93 words
An electroacoustical transducer assembly, comprising: a relatively inflexible backplate having an electrically conductive major surface and having another electrically conductive surface electrically connected to said major surface on the opposite side thereof; a relatively flexible diaphragm having electrically conductive and electrically nonconductive surfaces on opposite sides thereof; and an electrically conductive spring, having a portion thereof fixedly attached to said electrically conductive opposite-side backplate surface, for connecting said backplate to an electrical circuit, for urging said major backplate surface into engagement with said electrically nonconductive diaphragm surface and for properly tensioning said diaphragm.
Claim 2
Dependent Claim
93 words
An electroacoustical transducer assembly, comprising: a relatively inflexible backplate having an electrically conductive major surface and having another electrically conductive surface electrically connected to said major surface on the opposite side thereof; a relatively flexible diaphragm having electrically conductive and electrically nonconductive surfaces on opposite sides thereof; and an electrically conductive spring, having a portion thereof fixedly attached to said electrically conductive opposite-side backplate surface, for connecting said backplate to an electrical circuit, for urging said major backplate surface into engagement with said electrically nonconductive diaphragm surface and for properly tensioning said diaphragm.
Claim 3
Dependent Claim
25 words
The apparatus of claim 1, wherein said conductive spring is configured to provide an electrically conductive path to an electrical circuit external of said transducer.
Claim 4
Dependent Claim
30 words
The apparatus of claim 1, wherein said electrically conductive spring is a leaf spring and a center portion of said leaf spring is fixedly attached to said opposite-side backplate surface.
Claim 5
Dependent Claim
30 words
The apparatus of claim 1, wherein said electrically conductive spring is a conventional coil spring and an end of said coil spring is fixedly attached to said opposite-side backplate surface.
Claim 6
Independent Claim
20 words
The apparatus of claims 3 or 4, wherein said electrically conductive spring is laser welded to said opposite-side backplate surface.
Claim 7
Dependent Claim
20 words
The apparatus of claim 1, wherein said backplate is constructed of aluminum and said spring is constructed of stainless steel.
Claim 8
Dependent Claim
16 words
The apparatus of claim 1, wherein said major backplate surface includes a plurality of concentric grooves.
Claim 9
Dependent Claim
28 words
The apparatus of claim 1, wherein said backplate is constructed of a plastic material with electrically conductive major and opposite-side surfaces that are electrically connected to one another.
Claim 10
Dependent Claim
90 words
In an electroacoustical transducer assembly comprising a relatively inflexible backplate having electrically conductive opposed major surfaces in common electrical connection, a flexible diaphragm extending across one of said major surfaces, an electrically conductive spring having one portion in engagement with the other of said major surfaces to urge said backplate into proper tensioning contact with said diaphragm and to provide electrical contact to said backplate, the improvement wherein said spring portion is fixedly attached to said backplate to provide a vibration resistant conductive path between said spring and said backplate.
Claim 11
Dependent Claim
90 words
In an electroacoustical transducer assembly comprising a relatively inflexible backplate having electrically conductive opposed major surfaces in common electrical connection, a flexible diaphragm extending across one of said major surfaces, an electrically conductive spring having one portion in engagement with the other of said major surfaces to urge said backplate into proper tensioning contact with said diaphragm and to provide electrical contact to said backplate, the improvement wherein said spring portion is fixedly attached to said backplate to provide a vibration resistant conductive path between said spring and said backplate.
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) | 1986-10-10 | 1987-04-11 | 1987-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-10 | 1991-04-11 | 1991-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-10 | 1995-04-11 | 1995-10-11 | $7700.00 | Window Closed / Lapsed |