Patent ID: 9709919
Date: 2017-07-18
CPC Classifications: G03G

Claim:
1. A developing device comprising: a casing containing a two-component developer including toner and carrier; a developer bearer configured to carry the two-component developer on a surface of the developer bearer to transfer the two-component developer to a developing area facing a latent image bearer; a toner density sensor circuit configured to output an output value in accordance with toner density of the two-component developer inside the casing; and circuitry configured to: wherein the circuitry is configured to calculate a correction value for correcting the output value of the toner density sensor circuit based on the bulk density fluctuation, corrects the output value of the toner density sensor circuit based on the correction value, the circuitry is configured to estimate whether a current carrier charge at a timing at which the correction value is calculated differs from a carrier charge at a timing at which a previous correction value is calculated, and when the fluctuation in the current carrier charge with respect to the carrier charge obtained at the timing of the previous correction value is estimated as being less than a threshold, the circuitry is configured to cancel the calculation of the correction value.