Patent US3859477A successfully refreshed from Google Patents.
US3859477A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic transducer
Assignee: Tesla AS
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Filing: 1973-07-18
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Granted: 1975-01-07
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Expires: 1993-07-18
Abstract
Abstract An electrostatic transducer of the condenser type used as a loudspeaker and/or microphone comprising an assembly of at least one fixed electrode, a diaphragm and a spacer arranged therebetween. The assembly is spirally wound about a central core into a substantially cylindrical shape. The acoustic input/output thereof being situated at at least one of the frontal ends of the cylinder.
Inventors
- 👤 Zdenek Skvor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:08
CPC Classifications
H; H04; H04R; H04R19/00; H04R19/02
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
164 words
An electrostatic transducer capable of receiving and transmitting, comprising an assembly of a pair of elongate fixed electrodes, alternating with a pair of conforming diaphragms and two pairs of similarly elongate dielectric strip spacers, said assembly being convoluted into a tight spirally wound cylinder having the electrodes, and diaphragms alternating successively from the center to the outer periphery thereof, each separated by a spacer strip in contiguous contact therewith, said spacer strips being constructed in the configuration of a unitary comb-like structure to provide in said tight spirally wound cylinder a plurality of separated ports being open to free space on one plane which would lie on a base, herein termed frontal end, of said cylinder and closed on another plane which would lie on the opposite base, herein also termed frontal end, of said cylinder for each spacer strip, said ports providing a free space between successive radial convolutions of said electrodes and diaphragms, the accoustic input/outputs of said transducer being said ports.
Claim 2
Dependent Claim
164 words
An electrostatic transducer capable of receiving and transmitting, comprising an assembly of a pair of elongate fixed electrodes, alternating with a pair of conforming diaphragms and two pairs of similarly elongate dielectric strip spacers, said assembly being convoluted into a tight spirally wound cylinder having the electrodes, and diaphragms alternating successively from the center to the outer periphery thereof, each separated by a spacer strip in contiguous contact therewith, said spacer strips being constructed in the configuration of a unitary comb-like structure to provide in said tight spirally wound cylinder a plurality of separated ports being open to free space on one plane which would lie on a base, herein termed frontal end, of said cylinder and closed on another plane which would lie on the opposite base, herein also termed frontal end, of said cylinder for each spacer strip, said ports providing a free space between successive radial convolutions of said electrodes and diaphragms, the accoustic input/outputs of said transducer being said ports.
Claim 3
Dependent Claim
41 words
The transducer according to claim 1 including an acoustic wave guide axially located at at least one end of said cylindrical assembly, said wave guide having an input cross-section substantially equal to the area of the frontal end of said transducer.
Claim 4
Dependent Claim
24 words
The transducer according to claim 1 wherein a variable charge is impressed upon the fixed electrodes about said assembly operating as a push-pull transducer.
Claim 5
Dependent Claim
32 words
The transducer according to claim 1 wherein a variable charge is impressed between at least one diaphragm and at least one of said fixed electrodes, said assembly operating as a pressure transducer.
Claim 6
Dependent Claim
22 words
The transducer according to claim 1 wherein an amplifier is attached to said fixed electrodes, said assembly operating as a microphone receiver.
Claim 7
Dependent Claim
22 words
The transducer according to claim 1, including a central core formed of insulator material, said convoluted assembly being secured about said core.
Claim 8
Dependent Claim
31 words
The transducer according to claim 6 wherein said fixed electrodes, diaphragms, and spacers comprise elongated narrow strips wound about said core in the direction of the longitudinal axis of the strips.
Claim 9
Dependent Claim
39 words
The transducer according to claim 1 wherein said spacers comprise elongated strips of insulator material, said spacers being alternatively arranged with respect to said one plane so that input/output ports are provided on both frontal ends of said assembly.
Claim 10
Dependent Claim
20 words
The transducer according to claim 8 wherein at least one of the frontal ends of said cylindrical assembly are planar.
Claim 11
Dependent Claim
20 words
The transducer according to claim 8 wherein at least one of the frontal ends of said cylindrical assembly is curved.
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) | 1978-01-06 | 1978-07-08 | 1979-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-06 | 1982-07-08 | 1983-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-06 | 1986-07-08 | 1987-01-07 | $7700.00 | Window Closed / Lapsed |