Chord indicator for instruments having organ and piano-type keyboards

Claim 1

A chord teaching aid for instruments having a piano or organ-type keyboard adapted to be connected to a source of electric power, said aid including: a. an indicator panel having a first row of lights adapted to be aligned with the keys of the instrument extending over two octaves, b. the lights representing the black keys indicating the black keys as sharps, c. a second row of electric lights on the indicator panel representing only the black keys indicating the black keys are flats, d. lead means separately grounding each of the indicator lights representing white keys, e. electrically operated relay switch means connectable to the power source adapted when in a deenergized condition for connecting all the indicator lights of the first row representing black keys to ground, and in an energized condition adapted to connect only the indicator lights of the second row indicating that the black keys are flats to ground, f. a chord selector assembly operable remote from the indicator panel for connecting the indicator lights to the source of electric power, said assembly including: i. a base plate having a row of base contact elements arranged thereon in equidistantly spaced relationship and equal in number to total number of the first row of indicator lights connecting each of the base contact elements to its associated indicator lights representing a white key and a lead connecting each contact element with its associated indicator light representing a black instrument key, ii. a carriage mounted for slidable movement over the base plate longitudinally of the row of spaced contact elements thereon, iii. a row of contact elements on the carriage connectable in circuit to the power source for slidably contacting the base contact elements, said carriage contact elements being equal in number to the total number of notes required to be played for the selected chord and being so spaced so that when a first carriage contact element is positioned over any base contact element which represents the chord root note, the remainder of the carriage contact elements contact the base contact elements which represent the total number of notes, iv. a plurality of normally open chord selector switches mounted on the carriage for connecting selected carriage contact elements in circuit with one side of the power source, each switch representing one of the selected chords and being adapted when operated from the open to closed position to connect those carriage contact elements representing the notes of any chord selected to the source of electric power so as to energize the indicator lights associated with any of the base contact elements contacted by the carriage contact elements which are connected to the source of power, g. flat selector switch means in circuit between the relay switch and the power source for closing the relay switch circuit only when the black key notes of the chord selected are flats.