Patent ID: 7536120
Filing Date: 2009-05-19
Classification: G03G

Abstract:
1. An image forming apparatus comprising: a first developing device for developing an electrostatic image with a first developer including a first toner; a second developing device for developing an electrostatic image with a second developer including a second toner which is different from the first toner; a first supplying device for supplying the first toner into said first developing device; a second supplying device for supplying the second toner into said second developing device; a toner content detecting device for detecting a toner content in the first developer in said first developing device; an image density detecting device for detecting an image density of a reference toner image formed using said first developing device and said second developing device; and a controller for operating said image forming apparatus selectively in: wherein when the toner is supplied on the basis of a result of detection, by said image density detecting device, of the reference toner image formed at a predetermined interval or for each of a predetermined number of image formations in each of the first and second modes, said controller operates said image forming apparatus such that the predetermined interval is longer, or the predetermined number of image formations is greater in the first mode than in the second mode.