Patent US4679240A successfully refreshed from Google Patents.
US4679240A
Expired / Lapsed
US
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Touch sensitive hearing aid volume control circuit
Assignee: OMNI HEARING SYSTEMS A CORP OF KANSAS
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Filing: 1985-04-15
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Granted: 1987-07-07
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Expires: 2005-04-15
Abstract
Abstract A touch sensitive electronic volume control circuit so that the gain of an amplifier can be changed to any level from zero to maximum and the gain can be retained for periods of time without user adjustment or for power supply replacement.
Inventors
- 👤 Jorgen Heide
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:42
CPC Classifications
H; H03; H03G; H03G3/00; H03G3/02; H03G3/04; H03G3/10; H04; H04R; H04R25/00; H01; H01H; H01H2300/00; H01H2300/004; H04R25/50; H04R25/65
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
293 words
A hearing aid, comprising: a housing; a sound sensing means located in the housing and having an output signal; a sound producing means located in the housing and having a signal input; an amplifier located in the housing and having a gain control input responsive to a change in the impedance connected to the gain control input, a signal input and an amplified signal output, with the sensing means output signal connected to the signal input and the amplified signal output connected to the producing means signal input; a direct current voltage source located in the housing and having a positive and a negative terminal a field effect transistor having a gate, a source and a drain located in the body, the source being coupled to one of (a) the negative terminal of the voltage source or (b) the gain control input of the amplifier and the drain being correspondingly coupled to the other of (a) the negative terminal of the voltage source or (b) the gain control input of the amplifier; a first capacitor located in the housing and connected between the gate and the negative terminal of the voltage source; a first and a second contact set, each contact set being mounted on the housing and comprising at least two conductive contacts spaced sufficiently close to be bridged by touch, the first contact set being connected between the gate and the negative terminal of the voltage source and the second contact set being connected between the gate and the positive terminal of the voltage source so that when the first contact set is touched the impedance from the drain to the source of the transistor increases and when the second contact set is touched the transistor drain to source impedance decreases.
Claim 2
Dependent Claim
293 words
A hearing aid, comprising: a housing; a sound sensing means located in the housing and having an output signal; a sound producing means located in the housing and having a signal input; an amplifier located in the housing and having a gain control input responsive to a change in the impedance connected to the gain control input, a signal input and an amplified signal output, with the sensing means output signal connected to the signal input and the amplified signal output connected to the producing means signal input; a direct current voltage source located in the housing and having a positive and a negative terminal a field effect transistor having a gate, a source and a drain located in the body, the source being coupled to one of (a) the negative terminal of the voltage source or (b) the gain control input of the amplifier and the drain being correspondingly coupled to the other of (a) the negative terminal of the voltage source or (b) the gain control input of the amplifier; a first capacitor located in the housing and connected between the gate and the negative terminal of the voltage source; a first and a second contact set, each contact set being mounted on the housing and comprising at least two conductive contacts spaced sufficiently close to be bridged by touch, the first contact set being connected between the gate and the negative terminal of the voltage source and the second contact set being connected between the gate and the positive terminal of the voltage source so that when the first contact set is touched the impedance from the drain to the source of the transistor increases and when the second contact set is touched the transistor drain to source impedance decreases.
Claim 3
Dependent Claim
35 words
The hearing aid of claim 1, wherein the amplifier gain increases as the impedance connected to the gain control input decreases and the gain decreases as the impedance connected to the gain control input increases.
Claim 4
Dependent Claim
31 words
The hearing aid of claim 1, wherein the source is directly connected to the negative terminal of the voltage source and the drain is directly connected to the gain control input.
Claim 5
Dependent Claim
31 words
The hearing aid of claim 1, wherein the source is capacitively coupled to the negative terminal of the voltage source and the drain is capacitively coupled to the gain control input.
Claim 6
Dependent Claim
47 words
The hearing aid of claim 3 or 4 wherein continuous touching of the first contact set produces a continuous increase in the transistor drain to source impedance and wherein continuous touching of the second contact set produces a continuous decrease in the transistor drain to source impedance.
Claim 7
Dependent Claim
14 words
The hearing aid of claim 3 or 4, wherein the transistor is a MOSFET.
Claim 8
Dependent Claim
17 words
The hearing aid of claim 3 or 4, wherein the first capacitor is a low leakage capacitor.
Claim 9
Dependent Claim
45 words
The hearing aid of claim 1 wherein continuous touching of the first contact set produces a continuous increase in the transistor drain to source impedance and wherein continuous touching of the second contact set produces a continuous decrease in the transistor drain to source impedance.
Claim 10
Dependent Claim
12 words
The hearing aid of claim 1, wherein the transistor is a MOSFET.
Claim 11
Dependent Claim
15 words
The hearing aid of claim 1, wherein the first capacitor is a low leakage capacitor.
Claim 12
Dependent Claim
31 words
The hearing aid of claim 1, wherein the source is directly connected to the gain control input and the drain is directly connected to the negative terminal of the voltage source.
Claim 13
Dependent Claim
31 words
The hearing aid of claim 1, wherein the source is capacitively coupled to the gain control input and the drain is capacitively coupled to the negative terminal of the voltage source.
Claim 14
Dependent Claim
204 words
A touch sensitive volume control circuit, comprising: a direct current voltage source having a positive and a negative terminal; an amplifier having a gain control input responsive to an impedance connected to the gain control input; a field effect transistor having a gate, a source and a drain, the source being selectively coupled to one of (a) the negative terminal of the voltage source or (b) the gain control input and the drain being correspondingly coupled to the other of (a) the negative terminal of the voltage source or (b) the gain control input; a first capacitor connected between the gate and the negative terminal of the voltage source; a first and a second contact set, each contact set comprising two conductive contacts spaced sufficiently close to be bridged by touch, the first contact set being connected between the gate and the negative terminal of the voltage source and the second contact set being connected between the gate and the positive terminal of the voltage source so that when the first contact set is touched the impedance from the drain to the source of the transistor is increased and when the second contact set is touched the transistor drain to source impedance is decreased.
Claim 15
Dependent Claim
204 words
A touch sensitive volume control circuit, comprising: a direct current voltage source having a positive and a negative terminal; an amplifier having a gain control input responsive to an impedance connected to the gain control input; a field effect transistor having a gate, a source and a drain, the source being selectively coupled to one of (a) the negative terminal of the voltage source or (b) the gain control input and the drain being correspondingly coupled to the other of (a) the negative terminal of the voltage source or (b) the gain control input; a first capacitor connected between the gate and the negative terminal of the voltage source; a first and a second contact set, each contact set comprising two conductive contacts spaced sufficiently close to be bridged by touch, the first contact set being connected between the gate and the negative terminal of the voltage source and the second contact set being connected between the gate and the positive terminal of the voltage source so that when the first contact set is touched the impedance from the drain to the source of the transistor is increased and when the second contact set is touched the transistor drain to source impedance is decreased.
Claim 16
Dependent Claim
30 words
The circuit of claim 13, wherein the source is directly connected to the negative terminal of the voltage source and the drain is directly connected to the gain control input.
Claim 17
Dependent Claim
30 words
The circuit of claim 13 wherein the source is capacitively coupled to the negative terminal of the voltage source and the drain is capacitively coupled to the gain control input.
Claim 18
Dependent Claim
47 words
The hearing aid of claim 14 or 15, wherein continuous touching of the first contact set produces a continuous increase in the transistor drain to source impedance and wherein continuous touching of the second contact set produces a continuous decrease in the transistor drain to source impedance.
Claim 19
Dependent Claim
17 words
The circuit of claim 14 or 15, wherein the field effect transistor has a high input impedance.
Claim 20
Dependent Claim
11 words
The circuit of claim 17, wherein the transistor is a MOSFET.
Claim 21
Dependent Claim
16 words
The circuit of claim 14 or 15, wherein the first capacitor is a low leakage capacitor.
Claim 22
Dependent Claim
45 words
The hearing aid of claim 13, wherein continuous touching of the first contact set produces a continuous increase in the transistor drain to source impedance and wherein continuous touching of the second contact set produces a continuous decrease in the transistor drain to source impedance.
Claim 23
Dependent Claim
15 words
The circuit of claim 13, wherein the field effect transistor has a high input impedance.
Claim 24
Dependent Claim
11 words
The circuit of claim 21, wherein the transistor is a MOSFET.
Claim 25
Dependent Claim
14 words
The circuit of claim 13, wherein the first capacitor is a low leakage capacitor.
Claim 26
Dependent Claim
30 words
The circuit of claim 13, wherein the source is directly connected to the gain control input and the drain is directly connected to the negative terminal of the voltage source.
Claim 27
Dependent Claim
30 words
The circuit of claim 13, wherein the source is capacitively coupled to the gain control input and the drain is capacitively coupled to the negative terminal of the voltage source.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-07-06 | 1991-01-05 | 1991-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-06 | 1995-01-05 | 1995-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-06 | 1999-01-05 | 1999-07-07 | $7700.00 | Window Closed / Lapsed |