Patent ID: 9037007
Filing Date: 2015-05-19
Classification: G03G

Abstract:
1. An image forming apparatus, comprising: a toner case for storing toner; a developing device configured to attach toner to an electrostatic latent image formed on an image carrier, so as to form a toner image on the image carrier; a toner sensor configured to detect an amount of the toner in the developing device; a toner supply mechanism configured to supply the developing device with the toner stored in the toner case, based on an output value of the toner sensor; a dot-count calculation section configured to count, based on image data, the number of dots printed on a transfer target, and calculate, based on a count value, a toner consumption amount that is an amount of the toner consumed in the developing device; a toner supply amount calculation section configured to calculate a toner supply amount that is an amount of the toner supplied by the toner supply mechanism from the toner case to the developing device; a cumulative toner supply amount holding section configured to hold a cumulative toner supply amount that is a cumulative amount of the toner supplied from a point when use of the toner in the toner case is started; a correction toner supply amount calculation section configured to calculate a correction toner supply amount that is a used amount of the toner in the toner case, based on the toner consumption amount and the toner supply amount, the toner consumption amount being calculated by the dot-count calculation section, and the toner supply amount being calculated by the toner supply amount calculation section; and a cumulative toner supply amount updating section configured to add the correction toner supply amount and the cumulative toner supply amount, and store a value resulting from the addition as a new cumulative toner supply amount in the cumulative toner supply amount holding section, the correction toner supply amount being calculated by the correction toner supply amount calculation section, and the cumulative toner supply amount being held by the cumulative toner supply amount holding section.