Patent ID: 6381419
Filing Date: 2002-04-30
Classification: G03G

Abstract:
An image forming apparatus comprising:a developing device for developing an electrostatic image formed on an image bearing member by a developer; a developer supplying unit detachably attachable to a main body of said image forming apparatus for supplying the developer to said developing device; density detecting means for detecting a density of the developer in said developing device; and developer remaining amount detecting means for detecting information regarding a remaining amount of the developer in said developer supplying unit; a state of said developer supplying unit being judged on the basis of a result of the detection by said density detecting means and a result of the detection by said developer remaining amount detecting means, wherein said developer supplying unit is provided with a supply port for supplying the developer to said developing device therethrough, and a seal member for openably sealing said supply port, and when it is judged from the result of the detection by said developer remaining amount detecting means that the amount of the developer in said developer supplying unit exceeds a predetermined value and said developer supplying unit is a new condition and it is detected from the result of the detection by said density detecting means that the density of the developer is lower than a predetermined value, it is judged that opening of said seal member has not been effected.