US4250415A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electromechanical transducers
Assignee: Individual
•
Filing: 1978-06-29
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Granted: 1981-02-10
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Expires: 1998-06-29
Abstract
Abstract The invention relates to electromechanical transducers comprising an electret 4 between two electricity conducting electrodes 1 and 2. A solid intermediate layer 7 having a different deformability from that of the electret is placed between said electret and an electrode, the material forming said layer having an electrical resistivity higher than 10 15 ohms.cm (for instance a silicone elastomer) and said layer having a smooth and continuous face in intimate contact with the whole of the useful area of the charged face of the electret.
Inventors
- 👤 Jacques Lewiner
- 👤 Claude Hennion
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:38
CPC Classifications
H; H04; H04R; H04R19/00; H04R19/01; H02; H02N; H02N1/00; H02N1/06; H02N1/08
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
127 words
An electro-mechanical transducer comprising disposed between two electrically conducting electrodes which have connected to the same outside utilization circuit, on the one hand, an electret comprising a dielectric foil permanently electrically charged on at least one of its two faces or adjacent thereto, and on the other hand, disposed between said at least one face of the electret and the facing electrode face, a solid intermediate layer made from a material having a deformability different from that of the electret, the material forming said intermediate layer having an electrical resistivity at least greater than 10 15 ohms/cm and said intermediate layer having a smooth and continuous face in intimate contact with the whole of the useful area of said at least one charged face of the electret.
Claim 2
Dependent Claim
127 words
An electro-mechanical transducer comprising disposed between two electrically conducting electrodes which have connected to the same outside utilization circuit, on the one hand, an electret comprising a dielectric foil permanently electrically charged on at least one of its two faces or adjacent thereto, and on the other hand, disposed between said at least one face of the electret and the facing electrode face, a solid intermediate layer made from a material having a deformability different from that of the electret, the material forming said intermediate layer having an electrical resistivity at least greater than 10 15 ohms/cm and said intermediate layer having a smooth and continuous face in intimate contact with the whole of the useful area of said at least one charged face of the electret.
Claim 3
Dependent Claim
17 words
A transducer according to claim 1, characterized in that the intermediate layer is formed from an elastomer.
Claim 4
Dependent Claim
15 words
A transducer according to claim 2, characterized in that the elastomer comprises a silicone-based composition.
Claim 5
Dependent Claim
22 words
A transducer according to claim 2, characterized in that the elastomer is in the form of a foam with an integral skin.
Claim 6
Dependent Claim
11 words
A transducer according to claim 3 wherein said elastomer comprises methylvinylsiloxane.
Claim 7
Dependent Claim
11 words
A transducer according to claim 3 wherein said elastomer comprises methyvinylphenylsiloxane.
Claim 8
Dependent Claim
17 words
A transducer according to claim 1, characterized in that the intermediate layer comprises an aluminum oxide-based composition.
Claim 9
Dependent Claim
21 words
A transducer according to claim 1, characterized in that the electrodes, the electret and the intermediate layer are coaxial and concentric.
Claim 10
Dependent Claim
42 words
A transducer according to claim 1, for which the intermediate layer and the electret are both include parallel flat faces, said transducer being arranged so as to expose its intermediate layer to pressure variations generated by the simple touch of a finger.
Claim 11
Dependent Claim
47 words
A transducer according to claim 9, wherein said transducer is associated with several other transducers of the same type, each actuatable through an aperture in a rigid cover, all the apertures in said cover being aligned with each other so as to form a multiple control keyboard.
Claim 12
Dependent Claim
29 words
A transducer according to claim 1, characterized in that the intermediate layer is formed from a material having a thermal expansion coefficient distinctly different from that of the electret.
Claim 13
Dependent Claim
72 words
A transducer according to claim 1, characterized in that the electret and the intermediate layer are formed from materials having absorption coefficients distinctly different for certain radiations, thereby resulting in differences in heating and thus in the deformation of these materials, the assembly of the electrodes, the electret and the intermediate layer being arranged so that the layer and the electret may be reached by such radiations emitted from outside the electrodes.
Claim 14
Dependent Claim
64 words
A transducer according to claim 1, further comprising, stacked successively on each of the two faces of a common central electrode, an electret, an intermediate layer made from of material which deforms differently than the last-mentioned electret and which has an electrical resistivity greater than 10 15 ohms/cm. and a second electrode, the order of stacking of the layer and the electret being reversible.
Claim 15
Dependent Claim
19 words
A transducer according to claim 1 wherein the transducer is associated with an electrical circuit of the MOS type.
Claim 16
Dependent Claim
38 words
A transducer according to claim 14, characterized in that the MOS type electrical circuit comprises a resistor determining the input impedance, an inverter and a feed-back resistor, the output of this circuit being applied to a utilization circuit.
Claim 17
Dependent Claim
28 words
A transducer according to claim 1, wherein the transducer is associated with a dead point overshoot resilient control mechanism allowing the trigger pressure threshold to be accurately determined.
References Cited (Backward Citations)
US3967027A
Cited
US3736436A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-02-10 | 1984-08-11 | 1985-02-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-10 | 1988-08-11 | 1989-02-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-10 | 1992-08-11 | 1993-02-10 | $7700.00 | Window Closed / Lapsed |