Automatic rhythm sound producing device adapted for use with keyboard musical instruments

Claim 1

An automatic rhythm sound producing device adapted for use with a keyboard musical instrument which includes a first playing section having-a plurality of keys arranged in the order of musical notes for playing tones of a melody and those of an accompaniment upon selective depression of said keys, said first playing section being separate from said automatic rhythm sound producing device, said automatic rhythm sound producing device comprising: a clock pulse generator for generating a repetitive frequency signal corresponding to a multiple of the basic rhythm frequency; a frequency dividing counter chain including a plurality of counter stages and coupled with the clock pulse generator for counting down to submultiples of the frequency of signals generated from said clock pulse generator and including a resetting means for maintaining said counter chain normally inoperative; a timing pulse encoder connected to the stages of said counter chain for producing a plurality of rhythm pattern signals each being comprised of a preset different combination of output signals from said clock generator; a plurality of rhythm sound generators supplied with said respective rhythm pattern signals for producing a preset rhythm sound corresponding to a rhythm pattern selected from the output rhythm pattern signals of said encoder; and circuit means coupled to said first playing section to generate a trigger pulse upon detection of the depression of a key in the keyboard of said separate first playing section, and connected to said counter chain through the said resetting means to initiate the operation of said counter chain responsive to said detection of the depression of a key in said first playing section, thereby automatically initiating generation of rhythm sounds.