Patent ID: 8331817

Claim:
An image forming apparatus comprising: a developing device for developing a latent image formed on an image bearing member on the basis of image information, into a developed image with a developer, said developing device including a developer accommodating portion for accommodating the developer and a stirring member for stirring the developer in said developer accommodating portion; an optical remaining amount detecting device for detecting a remaining amount of the developer in said developer accommodating portion, by passing light through an inside of said developer accommodating portion; a consumption amount calculation device for calculating a consumption amount of the developer on the basis of the image information; and an outputting device for outputting an information signal indicative of a developer remaining amount, wherein: (1) when a drive time, which is an elapsed drive time of said stirring member since a start of continuously driving said stirring member during an image forming operation, is not shorter than a reference value, said outputting device outputs an information signal based on a detection result of said optical remaining amount detecting device, and (2) when the drive time is shorter than the reference value, a comparison is made between the consumption amount and a threshold, such that: (2-1) when the consumption amount is not less than the threshold, the image forming operation is temporarily interrupted, said stirring member is rotated, and then said outputting device outputs the information signal based on the detection result, and (2-2) when the consumption amount is less than the threshold, said outputting device outputs an information signal based on the consumption amount.