Pedal control circuits for electronic piano

Claim 2

In an electronic musical instrument, the combination comprising: a plurality of playing keys each adapted to be operated between a normal position and an operated position, a single pole-double throw key switch operatively associated with each playing key with its movable contactor arranged to engage a first contact when said playing key is in the normal position to engage a second contact when said playing key is in its operated position, first circuit means including a first capacitor associated with each of said playing keys for producing a tone signal having a peak amplitude determined by the level of a voltage appearing across said first capacitor, pulse generating means associated with each of said playing keys including a second capacitor connected to the movable contactor of the associated keyswitch operative in response to movement of a playing key from its normal position to its operated position for generating a voltage pulse having a peak amplitude determined by the magnitude of a voltage applied to said second capacitor, means for coupling a voltage pulse from said pulse generating means to said first capacitor for rapidly charging said first capacitor to a level determined by the amplitude of said voltage pulse, player-operated volume control pedal means adapted to be moved from a first position to at least one other position, and second circuit means connected to the first contact of said key switch and operatively associated with said control pedal means for applying to said second capacitor a voltage having a first predetermined amplitude when said control pedal means is at said first position and for applying to said second capacitor a second different predetermined voltage when said pedal control means is at said at least one other position.

Claim 3

Apparatus according to claim 1, wherein said second circuit means comprises a switch operative when said control pedal means is at its first position to apply a first predetermined voltage to said pulse generating means, and operative when said control pedal means is at said at least one other position to apply a second different predetermined voltage to said pulse generating means.

Claim 4

Apparatus according to claim 1, wherein said second circuit means comprises a potentiometer having a movable contact controlled by said control pedal means and operative when said control pedal means is in its first position to apply a first predetermined voltage to said pulse generating means, and operative when said control pedal means is at different other positions to apply different predetermined voltages to said pulse generating means at each of said other positions.

Claim 5

In an electronic musical instrument, the combination comprising, a plurality of playing keys each adapted to be moved between a normal position and an operated position, organ tone generator means for generating an organ tone in response to operation of a playing key from its normal position to its operated position, first circuit means including a first capacitor for producing a piano tone signal having an amplitude determined by the level of a voltage appearing across said first capacitor, pulse generating means including a second capacitor operative in response to operation of a playing key from its normal position to its operated position for generating a voltage pulse having a peak amplitude determined by the magnitude of a voltage applied to said second capacitor, means for coupling said voltage pulse from said pulse generating means to said first capacitor for rapidly charging said first capacitor to a level determined by the peak amplitude of said pulse, a player-operated control pedal adapted to be moved from a first position to at least one other position, an organ expression device connected to said organ tone generator means and operatively associated with said control pedal for controlling the amplitude of said organ tone signals, and second circuit means operatively associated with said control pedal for applying a voltage of first predetermined magnitude to said second capacitor when said control pedal is at said first position and for applying to said second capacitor a voltage of second predetermined different magnitude when said control pedal is at said at least one other position, whereby the amplitude of the organ tone signals is a continuous function of the position of said control pedal and the peak amplitude of the piano tone signals is determined by the position of said control pedal at the moment of strike only of a playing key.

Claim 6

In an electronic musical instrument, the combination comprising, a plurality of playing keys each adapted to be moved between a normal position and an operated position, organ tone generator means for generating an organ tone in response to operation of a playing key from its normal position to its operated position, first circuit means including a first capacitor for producing a piano tone signal having an amplitude determined by the level of a voltage appearing across said first capacitor, pulse generating means including a second capacitor operative in response to operation of a playing key from its normal position to its operated position for generating a voltage pulse having a peak amplitude determined by the magnitude of a voltage applied to said second capacitor, means for coupling said voltage pulse from said pulse generating means to said first capacitor for rapidly charging said first capacitor to a level determined by the peak amplitude of said pulse, a player-operated control pedal adapted to be moved from a first position to at least one other position, an organ expression device connected to said organ tone generator means and operatively associated with said control pedal for controlling the amplitude of said organ tone signals, and second circuit means operatively associated with said control pedal for applying a voltage of first predetermined magnitude to said second capacitor when said control pedal is at said first position and for applying to said second capacitor a voltage of second predetermined different magnitude when said control pedal is at said at least one other position, whereby the amplitude of the organ tone signals is a continuous function of the position of said control pedal and the peak amplitude of the piano tone signals is determined by the position of said control pedal at the moment of strike only of a playing key.

Claim 7

In an electronic musical instrument, the combination comprising: a plurality of playing keys each adapted to be moved between a normal position and an operated position, a single pole-double throw keyswitch operatively associated with each playing key with its movable contactor arranged to engage a first contact when said playing key is n its normal position and to engage a second contact when said playing key is in its operated position, first circuit means including a first capacitor associated with each of said playing keys and each connected to the second contact of the associated keyswitch for producing a tone signal having a peak amplitude determined by the level of a voltage appearing across said first capacitor, second circuit means associated with each of said playing keys and each including a second capacitor connected to the movable contactor of the associated keyswitch, third circuit means connected to the first contact of each of said keyswitches including means for selectively applying to said second capacitor when the associated playing key is in its normal position one or the other of at least first and second potentials of different predetermined values for charging said second capacitor to the selected potential, and a movable player-operable control pedal operatively associated with said third circuit means and operative to select said first potential at a first operated position thereof and to select said second potential at a second operated position thereof for controlling the amplitude level, at the moment of strike only of a playing key, of the tone signal produced by said first circuit means.

Claim 8

In an electronic musical instrument, the combination comprising: a plurality of playing keys each adapted to be moved between a normal position and an operated position, a single pole-double throw keyswitch operatively associated with each playing key with its movable contactor arranged to engage a first contact when said playing key is n its normal position and to engage a second contact when said playing key is in its operated position, first circuit means including a first capacitor associated with each of said playing keys and each connected to the second contact of the associated keyswitch for producing a tone signal having a peak amplitude determined by the level of a voltage appearing across said first capacitor, second circuit means associated with each of said playing keys and each including a second capacitor connected to the movable contactor of the associated keyswitch, third circuit means connected to the first contact of each of said keyswitches including means for selectively applying to said second capacitor when the associated playing key is in its normal position one or the other of at least first and second potentials of different predetermined values for charging said second capacitor to the selected potential, and a movable player-operable control pedal operatively associated with said third circuit means and operative to select said first potential at a first operated position thereof and to select said second potential at a second operated position thereof for controlling the amplitude level, at the moment of strike only of a playing key, of the tone signal produced by said first circuit means.

Claim 9

Apparatus according to claim 5, wherein said third circuit means comprises a second single pole-double throw switch having its movable contactor connected to the first contact of said keyswitch, a first voltage source having said first predetermined potential connected to a first contact of said second switch, a second voltage source having said second predetermined potential connected to the second contact of said second switch, and wherein said apparatus further comprises means mechanically coupling said control pedal to the contactor of said second switch.

Claim 10

Apparatus according to claim 5, wherein said third circuit means comprises a potentiometer having a movable contact connected to the first contact of said keyswitch and controlled by said control pedal and operative when said control pedal is in a first operated position to charge said second capacitor to a first predetermined potential, and operative when said control pedal is at different other positions to charge said second capacitor to different predetermined potentials at each of said other positions.

Claim 11

Apparatus according to claim 7, wherein the combination further comprises: organ tone generator means for generating an organ tone in response to operation of a playing key from its normal position to its operated position, and an organ expression device connected to said organ tone generating means and operatively associated with said movable control pedal for controlling the amplitude of said organ tone signals as a function of the operated position of said control pedal.

Claim 12

Apparatus according to claim 8, wherein said organ expression device includes a second potentiometer connected between two sources of different potentials and having a movable contact controlled by said movable control pedal for controlling the amplitude of said organ tone signal as a continuous function of the position of said control pedal, whereas the peak amplitude of the piano tone signals is determined by the instantaneous position of said control pedal at the moment of strike only of a playing key.