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US3948137A Expired / Lapsed US ⏱️ 0.0 years remaining

Pitch determining voltage signal generating circuit for a voltage controlled type electronic musical instrument

Assignee: Nippon Gakki Co Ltd
•
Filing: 1975-03-12
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Granted: 1976-04-06
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Expires: 1995-03-12
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Abstract

Abstract This invention is directed to a keyboard circuit for generating pitch determining voltage signals whose voltage values exponentially vary with respect to notes. Key switches are connected between a DC voltage source and a voltage dividing resistance network, thus making it possible to use key switches having a simpler contact construction. Nevertheless, the keyboard circuit of the invention can act as a lower or higher tone preference circuit.

Inventors

  • 👤 Naoyuki Niinomi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 12:40
CPC Classifications
G; G10; G10H; G10H5/00; G10H5/002; G10H1/00; G10H1/18; Y; Y10; Y10S; Y10S84/00; Y10S84/02; Y10S84/08; Y10S84/20

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 197 words
In an electronic musical instrument comprising a keyboard circuit for producing at an output thereof a pitch determining voltage signal having a voltage representing the note of an actuated key, and a voltage controlled oscillator coupled to said keyboard circuit and responsive to the pitch determining voltage signal from the output of said keyboard circuit to generate a tone signal having a tone pitch which is a function of the pitch determining voltage signal, said keyboard circuit comprising: a DC voltage source; a voltage dividing network including a plurality of first resistors which are series connected and have a substantially equal resistance value, one end of the series-connection of said first resistors being connected to said output of said keyboard circuit, a second resistor connecting said output of said keyboard circuit to a reference potential point, and a plurality of third resistors connecting respective junctions between two adjacent series-connected first resistors to the reference potential point, said third resistors each having a substantially equal resistance value; and a plurality of key switches respectively connected between said DC voltage source and (i) each of said junctions and (ii) both ends of said series connection of said first resistors.
Claim 2
Dependent Claim 197 words
In an electronic musical instrument comprising a keyboard circuit for producing at an output thereof a pitch determining voltage signal having a voltage representing the note of an actuated key, and a voltage controlled oscillator coupled to said keyboard circuit and responsive to the pitch determining voltage signal from the output of said keyboard circuit to generate a tone signal having a tone pitch which is a function of the pitch determining voltage signal, said keyboard circuit comprising: a DC voltage source; a voltage dividing network including a plurality of first resistors which are series connected and have a substantially equal resistance value, one end of the series-connection of said first resistors being connected to said output of said keyboard circuit, a second resistor connecting said output of said keyboard circuit to a reference potential point, and a plurality of third resistors connecting respective junctions between two adjacent series-connected first resistors to the reference potential point, said third resistors each having a substantially equal resistance value; and a plurality of key switches respectively connected between said DC voltage source and (i) each of said junctions and (ii) both ends of said series connection of said first resistors.
Claim 3
Dependent Claim 30 words
An electronic musical instrument according to claim 1 wherein the resistance values of said first, second and third resistors r, R 1 and R have substantially the following relationships: ##EQU6##
Claim 4
Dependent Claim 22 words
An electronic musical instrument according to claim 1 wherein said key switches have a common terminal connected to said DC voltage source.
Claim 5
Dependent Claim 21 words
An electronic musical instrument according to claim 1 wherein each of said key switches is a single pole, single throw switch.
Claim 6
Dependent Claim 26 words
An electronic musical instrument according to claim 1 wherein said reference potential is at the same voltage level as one terminal of said DC voltage source.
Claim 7
Dependent Claim 15 words
An electronic musical instrument according to claim 5 wherein said reference potential is ground potential.
Claim 8
Dependent Claim 15 words
An electronic musical instrument according to claim 1 wherein said reference potential is ground potential.

References Cited (Backward Citations)

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US3417188A Cited
US3733955A Cited
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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) 1979-04-06 1979-10-06 1980-04-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-04-06 1983-10-06 1984-04-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-04-06 1987-10-06 1988-04-06 $7700.00 Window Closed / Lapsed

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