Patent US3764723A successfully refreshed from Google Patents.
US3764723A
Expired / Lapsed
US
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Voltage-controlled single tone selector for use in electronic musical instrument
Assignee: Nippon Gakki Co Ltd
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Filing: 1972-03-16
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Granted: 1973-10-09
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Expires: 1992-03-16
Abstract
Abstract A single tone selector for an electronic musical instrument provided with a plurality of tone generators and the same number of keys. Tone signals from the tone generators are respectively shunted by being connected to normally conducting voltage controlled diode switchers which are selectively rendered nonconductive one at a time in response to the different predetermined magnitudes of voltage. A key controlled variable voltage source generates upon key depression such magnitude of voltage as render the corresponding one of the diode switchers nonconductive to stop shunting the tone signal. The output voltages of the variable voltage source are supplied to the diode switchers by a common conductor. The variable voltage source is designed to generate such magnitude of voltage as renders only one of the diode switchers nonconductive even when two or more keys are simultaneously depressed. A tone signal from a tone generator corresponding to the diode switcher thus rendered nonconductive can be conducted to a common output terminal.
Inventors
- 👤 A Takeyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:58
CPC Classifications
G; G10; G10H; G10H1/00; G10H1/18; G10H1/22; Y; Y10; Y10S; Y10S84/00; Y10S84/02; Y10S84/23; Y10S84/25
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
196 words
A single tone selector for use in a keyboard type electronic musical instrument comPrising: a plurality of tone generators for producing tone signals; a common output terminal connected to said plurality of tone generators; a plurality of voltage controlled switching means of the same number as said plurality of tone generators and connected to said plurality of tone generators, said plurality of voltage controlled switching means being normally kept conducting so as to substantially shunt said tone generators thereby preventing said tone signals from being conducted to said common output terminal and being rendered non-conductive in response to voltages having predetermined different magnitudes, thereby enabling a tone signal to be produced at said output terminal; a plurality of keys of the same number as said tone generators; a key controlled variable voltage source means coupled to and controlled by operation of said plurality of keys so as to generate per key depression a voltage having a predetermined magnitude to render nonconductive the voltage controlled switching means corresponding to the depressed keys; and a common conductor means for supplying output voltages from said key controlled variable voltage source simultaneously to said plurality of voltage controlled switching means.
Claim 2
Dependent Claim
196 words
A single tone selector for use in a keyboard type electronic musical instrument comPrising: a plurality of tone generators for producing tone signals; a common output terminal connected to said plurality of tone generators; a plurality of voltage controlled switching means of the same number as said plurality of tone generators and connected to said plurality of tone generators, said plurality of voltage controlled switching means being normally kept conducting so as to substantially shunt said tone generators thereby preventing said tone signals from being conducted to said common output terminal and being rendered non-conductive in response to voltages having predetermined different magnitudes, thereby enabling a tone signal to be produced at said output terminal; a plurality of keys of the same number as said tone generators; a key controlled variable voltage source means coupled to and controlled by operation of said plurality of keys so as to generate per key depression a voltage having a predetermined magnitude to render nonconductive the voltage controlled switching means corresponding to the depressed keys; and a common conductor means for supplying output voltages from said key controlled variable voltage source simultaneously to said plurality of voltage controlled switching means.
Claim 3
Dependent Claim
16 words
A single tone selector according to claim 1 wherein said plurality of keys are pedal keys.
Claim 4
Dependent Claim
85 words
A single tone selector according to claim 1 wherein said voltage controlled switching means are each connected at one end to the corresponding tone generator through a first impedance means and also to said key controlled variable voltage source means through said common conductor means and further connected at the other end to a predetermined potential point grounded through a second impedance means; and wherein said common output terminal is connected to the junctions of said first impedance means and said voltage controlled switching means.
Claim 5
Dependent Claim
77 words
A single tone selector according to claim 3 wherein said first impedance means includes a capacitor and a resistor and said second impedance means includes a resistor; and wherein the resistance value of said resistor of said first impedance means is larger than that of said resistor of said second impedance means; and wherein said output terminal is connected to the junction of said first impedance means and said voltage controlled switching means through a coupling capacitor.
Claim 6
Dependent Claim
169 words
A single tone selector according to claim 1 wherein said voltage controlled switching means are diode switching means each including first and second diodes each having an anode and cathode, with the cathode of said first diode connected to the anode of said second diode and the junction thereof further connected to the corresponding tone generator through a first impedance means and also to said key controlled variable voltage source means through said common conductor means; there are further provided serially connected resistors, with a unit resistor at one end of said series connected to a D.C. source and another unit resistor at the opposite end of said series grounded, both ends of each of said serially connected resistors being connected to the anode of said first diode of the corresponding diode switching means and the cathode of said second diode thereof; and there are further provided coupling capacitor means for connecting the junction of said first impedance means and said diode switching means to said common output terminal.
Claim 7
Dependent Claim
17 words
A single tone selector according to claim 5 wherein said first and second diodes are germanium diodes.
Claim 8
Dependent Claim
32 words
A single tone selector according to claim 5 wherein said first impedance means includes a capacitor and a resistor which has a larger resistance value than that of said serially connected resistors.
Claim 9
Dependent Claim
156 words
A single tone selector according to claim 1 wherein said voltage controlled switching means are diode switching means including first and second diodes disposed parallel in opposite directions with the first junction of said first and second diodes connected to the correspOnding tone generator through a first impedance means and also to said key controlled variable voltage source means through said common conductor means; there are further provided a plurality of serially connected resistors with a unit resistor at one end of said series connected to a D.C. source and another unit resistor at the opposite end of said series grounded, the junctions of said serially connected resistors being connected to the second junctions of said first and second diodes of the corresponding diode switching means; and there are further provided a plurality of coupling capacitor means for connecting the junctions of said first impedance means and said diode switching means to said common output terminal.
Claim 10
Dependent Claim
17 words
A single tone selector according to claim 8 wherein said first and second diodes are silicon diodes.
Claim 11
Dependent Claim
31 words
A single tone selector according to claim 8 wherein said first impedance means includes a capacitor and a resistor which has a larger resistance than that of said serially connected resistors.
Claim 12
Dependent Claim
98 words
A single tone selector according to claim 1 wherein said key controlled variable voltage source comprises: a resistor body having substantially the same length as the fully arranged length of said plurality of keys; a D.C. source connected across said resistor body; and a common flexible contact means having substantially the same length as that of said resistor body, so disposed as to face said resistor body with a predetermined space therebetween and connected to said common conductor means, said common flexible contact means being adapted to be actuated by said keys to contact with said resistor body.
Claim 13
Dependent Claim
76 words
A single tone selector according to claim 1 wherein said key controlled variable voltage source means comprises: a resistor body having substantially the same length as the fully arranged length of said plurality keys and provided with taps having the same number as said keys; a D.C. source connected across said resistor body; and key switches adapted to be actuated by said keys to connect said taps of said resistor body of said common conductor means.
Claim 14
Dependent Claim
65 words
A single tone selector according to claim 1 further comprising a voltage memory circuit connected between said key controlled variable voltage source means and said voltage controlled switching means so as to store output voltages from said key controlled variable voltage source means, thereby allowing said output voltages to be continuously supplied to said voltage controlled switching means even after the release of said keys.
Claim 15
Dependent Claim
69 words
A single tone selector according to claim 13 wherein said voltage memory circuit includes a field effect transistor having a drain, source and gate, said drain being connected to a D.C. source, said source being grounded through a resistor and connected to said voltage controlled switching means and said gate being connected to the output of said key controlled variable voltage source means and further grounded through a capacitor.
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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) | 1976-10-08 | 1977-04-09 | 1977-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-08 | 1981-04-09 | 1981-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-08 | 1985-04-09 | 1985-10-09 | $7700.00 | Window Closed / Lapsed |