Automatic rhythm generator for electronic musical instrument

Claim 2

An automatic rhythm generator for an electronic musical instrument, comprising: an 35 accompaniment keyboard; a chord discrimination signal generator for generating a chord discrimination signal for a chord designated by said accompaniment keyboard; a detecting means for detecting a degree of change between the chord discrimination signal of the currently designated chord and a chord discrimination signal of an immediately preceding chord; memory means for sequentially storing the data representing said degree of change detected by said detecting means; a rhythm pattern change circuit means for changing the rhythm pattern in accordance with memory contents of said memory means; and means for producing rhythm tones in accordance with the rhythm pattern changed by said rhythm pattern change circuit.

Claim 3

An automatic rhythm generator according to claim 1, wherein the degree of change is obtained in accordance with a difference between roots of the currently designated chord and 45 the immediately preceding chord, and types of the currently designated chord and the immediately preceding chord.

Claim 4

An automatic rhythm generator according to claim 1, wherein the degree of change is obtained in accordance with the types of the currently designated chord and the immediately preceding chord.

Claim 5

An automatic rhythm generator according to claim 1, further comprising means for generating a plurality of chord change pattern data in accordance with the detected degree of chord change.

Claim 6

An automatic rhythm generator for an electronic musical instrument, comprising: an accompaniment keyboard; a code discrimination signal generator for generating a chord 55 discrimination signal for a chord designated by said accompaniment keyboard; a first detecting means for detecting a first degree of change between the chord discrimination signal of the currently designated chord and a chord discrimination signal of an immediately preceding chord; first memory means for sequentially storing the data representing said first degree of change; a second detecting means for detecting a second degree of change between the chord discrimina- 60 tion signal of the currently designated chord and a chord discrimination signal of a chord designated before a predetermined time interval; second memory means for storing the data representing said second degree of change; a rhythm pattern change circuit for changing the rhythm pattern in accordance with memory contents of said first and second memory means; and means for producing rhythm tones in accordance with the rhythm pattern changed by said 65 7 GB2156136A 7 rhythm pattern change circuit.

Claim 7

An automatic rhythm generator for an electronic musical instrument, comprising: an accompaniment keyboard; a code discrimination signal generator for generating a chord 55 discrimination signal for a chord designated by said accompaniment keyboard; a first detecting means for detecting a first degree of change between the chord discrimination signal of the currently designated chord and a chord discrimination signal of an immediately preceding chord; first memory means for sequentially storing the data representing said first degree of change; a second detecting means for detecting a second degree of change between the chord discrimina- 60 tion signal of the currently designated chord and a chord discrimination signal of a chord designated before a predetermined time interval; second memory means for storing the data representing said second degree of change; a rhythm pattern change circuit for changing the rhythm pattern in accordance with memory contents of said first and second memory means; and means for producing rhythm tones in accordance with the rhythm pattern changed by said 65 7 GB2156136A 7 rhythm pattern change circuit.

Claim 8

An automatic rhythm generator according to claim 5, further comprising means for generating a plurality of chord change pattern data in accordance with the detected first and second range of chord change.

Claim 9

An automatic rhythm generator according to claim 1, wherein said chord discrimination signal generator includes means for generating multi-bit data representing a chord name and a root of the chord.

Claim 10

An automatic rhythm generator according to claim 7, wherein said chord change memory circuit includes; a chord memory for storing precedingly designated chord data; chord comparison and calculation circuit for obtaining a difference data between the precedingly designated chord data stored in said chord memory and the currently designated chord data; chord change memory circuit for successively storing said difference data; means for driving said chord memory and chord change memory circuit when said difference data represents zero; and means for supplying an output of said chord change memory circuit to said rhythm pattern change circuit.

Claim 11

An automatic rhythm generator according to claim 8, wherein said chord comparison and calculation circuit has a function for calculating a difference between two pitches of roots in a successively obtained chord data; and said supplying means includes means for supplying bit data representing a chord name in a successively obtained chord data, to a rhythm pattern switch circuit, together with said difference data.

Claim 12

An automatic rhythm generator according to claim 1, wherein said rhythm pattern switch circuit includes means for successively comparing memory contents of said chord change memory circuit and chord change pattern memory circuit according to the progress of chord performance; means for outputting a rhythm pattern selection signal when a coincidence signal is outputted from said comparing means; and a rhythm pattern memory circuit being accessed by said rhythm pattern selection signal.

Claim 13

An automatic rhythm generator according to claim 7, wherein said chord change memory circuit includes a chord memory for storing precedingly designated chord data; a chord comparison and calculation circuit for obtaining difference data between the precedingly designaged chord data stored in said chord memory and currently designated chord data; a 30 chord change memory circuit for successively storing said difference data; means for driving said chord memory and chord change memory circuit according to the start of each measure; and means for supplying an output of said chord change memory circuit to said rhythm pattern switch circuit.

Claim 14

An automatic rhythm generator for electronic musical instrument, substantially as 35 hereinbefore described with reference to the accompanying drawings. Printed in the United Kingdom for Her Majesty's Stationery Office, Dd 8818935, 1985, 4235Published at The Patent Office, 2 5 Southampton Buildings, London, WC2A 1 AY, from which copies may be obtained.

Claim 15

An automatic rhythm generator for electronic musical instrument, substantially as 35 hereinbefore described with reference to the accompanying drawings. Printed in the United Kingdom for Her Majesty's Stationery Office, Dd 8818935, 1985, 4235Published at The Patent Office, 2 5 Southampton Buildings, London, WC2A 1 AY, from which copies may be obtained.