Patent ID: 7532828
Filing Date: 2009-05-12
Classification: G03G

Abstract:
1. An image forming apparatus, which uses a developing device including: a developer carrying member developing an electrostatic latent image formed on an electrophotographic photosensitive member with a developer; a developer containing portion containing the developer; an agitating member provided rotatably in the developer containing portion to agitate the developer; and a developer remaining amount detecting member outputting a signal for detecting a remaining amount of the developer contained in the developer containing portion, the image forming apparatus comprising: a main body controller to which the signal is input, and which detects the remaining amount by using a first detecting unit that sets a reference value serving as a reference for detecting the remaining amount by the signal, and thereafter calculates the remaining amount based on an amount of change in the signal from the reference value, and a second detecting unit that detects the remaining amount based on a band of fluctuation in the signal corresponding to a rotational period of the agitating member.