US4750207A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hearing aid noise suppression system
Assignee: Sivantos Inc
•
Filing: 1986-03-31
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Granted: 1988-06-07
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Expires: 2006-03-31
Abstract
Abstract A hearing aid responds to increased noise by changing its frequency response to reduce the effects of the noise. The hearing aid has a circuit which varies the frequency response of the unit as a function of low-frequency sounds, using a fast attack time and a much slower release time.
Inventors
- 👤 Anton M. Gebert
- 👤 Yuri Gokhin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:00
CPC Classifications
H; H04; H04R; H04R25/00; H04R25/50; H04R25/502; H03; H03G; H03G3/00; H03G3/20; H03G3/30; H03G3/32; H03G5/00; H03G5/16; H03G5/18
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
80 words
A hearing aid circuit, comprising: a high-pass filter with adjustable frequency response; a bandpass filter; and an attack and release circuit connecting the bandpass filter to the high-pass filter in a manner that an increased output from the bandpass filter changes the frequency response of the high-pass filter after an attack time and a decreased output from the bandpass filter changes the frequency response of the high-pass filter after a release time which is much longer than said attack time.
Claim 2
Dependent Claim
80 words
A hearing aid circuit, comprising: a high-pass filter with adjustable frequency response; a bandpass filter; and an attack and release circuit connecting the bandpass filter to the high-pass filter in a manner that an increased output from the bandpass filter changes the frequency response of the high-pass filter after an attack time and a decreased output from the bandpass filter changes the frequency response of the high-pass filter after a release time which is much longer than said attack time.
Claim 3
Dependent Claim
32 words
The hearing aid circuit of claim 1, wherein said high-pass filter comprises a filter capacitor and said attack and release circuit comprises a transistor with its collector-emitter circuit shunting said filter capacitor.
Claim 4
Dependent Claim
59 words
The hearing aid circuit of claim 2, wherein said attack and release circuit further comprises a timing capacitor which is connected to the base of said transistor, a charging resistor through which said timing capacitor is clamped, and a discharging resistor thereof which said timing capacitor is discharged, said charging resistor having a lower resistance than said discharging resistor.
References Cited (Backward Citations)
US3611145A
Cited
US3678416A
Cited
US3927279A
Cited
US3928733A
Cited
US4061875A
Cited
JPS5527742A
Cited
SU723791A1
Cited
US4363006A
Cited
US4405831A
Cited
US4425481A
Cited
US4425481B1
Cited
US4425481B2
Cited
DE3139088A1
Cited
DE3237988A1
Cited
US4490585A
Cited
US4517415A
Cited
US4506381A
Cited
US4419544A
Cited
JPS598500A
Cited
US4622692A
Cited
US4630302A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-06-07 | 1991-12-07 | 1992-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-06-07 | 1995-12-07 | 1996-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-06-07 | 1999-12-07 | 2000-06-07 | $7700.00 | Window Closed / Lapsed |