Patent ID: 8606124

Claim:
A toner cartridge comprising: a toner container configured to contain toner; a toner supplying opening formed in the toner container; a conveying member configured to convey the toner toward the toner supplying opening in the toner container; a driving gear configured to rotationally drive the conveying member; an agitating member configured to agitate the toner in the toner container; a driven gear configured to rotate in association with rotational driving of the driving gear to rotate the agitating member, wherein a number of teeth (N 1 ) of the driven gear is greater than a number of teeth (N 2 ) of the driving gear; and a rotational body configured to rotate according to rotation of the driven gear, having a plurality of light incidence parts in rotational circumference, wherein the number of the light incidence parts is 1/K′ or more when a ratio of the number of the teeth (N 1 ) and the number of the teeth (N 2 ) is K′=N 2 /N 1 .