Diatonic and chromatic chord dial

• US 3,908,506 A
• Filed: 02/22/1974
• Issued: 09/30/1975
• Est. Priority Date: 02/22/1974
• Status: Expired due to Term

• Current Assignee: Verna M. Leonard
• Original Assignee: Verna M. Leonard
• Inventors: Leonard, Verna M.
• Primary Examiner(s): Franklin, Lawrence R.
• Application Number:
  US05/444,897
• Time in Patent Office: 585 Days
• Field of Search: 84/470-485 235/88
• US Class Current: 84/471.00R
• CPC Class Codes: G09B 15/007 using disc-shaped boards
• CPC Class Codes: G10G 1/02 Chord or note indicators, fixed or adjustable, for keyboard of fingerboards

Abstract

A device for teaching music students the correspondence between the scale tone intervals of a chord as measured with reference to the chromatic scale and the diatonic scale. The teaching aid comprises an outer disc and a concentrically and rotatably mounted inner disc, the outer disc having a continuous peripheral display of the chord symbols of a particular chord in the various key signatures, and the inner disc having two preferably radially stepped portions having thereon peripheral displays of the diatonic and chromatic scale intervals of the particular chord. The student rotates the inner disc until the chromatic scale indicia are adjacent to a particular chord symbol on the outer disc and writes in the names of the scale tones of the chord, and then repeats the process for the diatonic scale. The two discs may be mounted on a backing panel having the actual spaces between the piano keys indicated on the bottom portion for display directly on a piano keyboard.

Claims

1. A teaching aid for correlating diatonic and chromatic scale intervals comprising:

a disc having in peripherally arranged segments, a plurality of arrays of indicia naming a particular type of chord in a like number of key signatures, two radially adjacent annular concentric rows of spaced blank squares being provided radially inwardly of said arrays of indicia for the inscription in duplicate of the names of the scale tones of the chords denoted by said arrays, the individual squares of each of said rows being in radial alignment with the individual squares of the other of said rows;

a planar member mounted centrally for rotative adjustment on said disc and having a major portion extending a radial distance from the central mounting thereof short of the inner row of said rows of squares, a first arcuate edged portion the edge of which falls substantially into alignment with the inner margin of the inner row of squares and a second arcuate edged portion adjacent the first portion the edge of which extends over the inner row of squares and falls substantially into alignment with the inner margin of the outer row of squares;

one of said arcuate edged portions having indicia adjacent the edge thereof denoting the chromatic scale tone intervals of the scale tones of said named particular type of chord, the chromatic scale indicia being arranged such that the scale intervals denoted thereon can be moved into individual juxtaposition with a number of squares upon proper rotative adjustment of said planar member;

the other of said arcuate edged portions having indicia adjacent the edge thereof denoting the diatonic scale tone intervals of the scale tones of said named particular type of chord, the diatonic scale indicia being arranged such that the scale intervals denoted thereon can be moved into individual justaposition with a like number of squares upon proper rotative adjustment of said planar member.