Abstract: An apparatus includes a lock member of a door that restricts, in a state in which a plurality of cartridges detachable from the apparatus is attached, removal of the plurality of consumable units from the apparatus. In a state in which a subscription contract of using a specific cartridge delivered from a service provider is made, in a case where at least one of the attached cartridges is the specific cartridge, the apparatus brings the lock member into a locked state, and when a predetermined unlock condition is satisfied, clears the locked state.

Abstract: An image forming apparatus to which a cartridge provided with a device including a memory is detachably mountable includes a controller for executing image formation control, an acquiring potion for acquiring first condition information which is image forming condition information from the memory in communication with the device, a verifying portion for verifying the first condition information acquired from the memory, a second condition information storing portion in which second condition information which is image forming condition information is stored, and an authenticating portion for executing authentication processing for authenticating the cartridge in communication with the device. The controller executes at least a part of the image formation control, using the first condition information or the second condition information selected on the basis of a verification result by the verifying portion, in parallel to the authentication processing by the authenticating portion.

Abstract: An image forming apparatus includes an image bearing member, a developing unit to develop an electrostatic latent image formed on the image bearing member with toner, and a detachable toner container in which toner for supplying to the developing unit is contained. A measuring unit measures information relating to an amount of toner in the developing unit, and a determination unit determines an amount of toner in the developing unit based on the measured information.

Abstract: An image forming apparatus includes an image bearing member; a developing device; a transfer member; a contact member provided downstream of the transfer member and upstream of the developing device with respect to a movement direction of a surface of the image bearing member and contacting the image bearing member at a contact portion, wherein the surface of the image bearing member passed through a transfer portion reaches the contact portion without being cleaned, a detecting portion for detecting a size of the sheet; and a controller for executing an operation in a cleaning mode for cleaning the contact member. The controller executes the operation in the cleaning mode when the controller discriminates that the size of the sheet detected by the detecting portion is smaller than a size of the toner image.

Abstract: The image forming apparatus includes an image bearing member, a developing unit for developing an electrostatic latent image formed on the image bearing member with toner, a cartridge that is detachably provided in an apparatus main body and that has at least the developing unit, a toner container that is detachably provided in the apparatus main body and that stores toner for supplying to the developing unit, a memory unit that stores information relating to a usage state of the cartridge, a measuring unit that measures an amount of toner in the developing unit, and a determination unit that determines the amount of toner in the developing unit based on information stored in the memory unit, information obtained by measurement by the measuring unit, and a measurement error of the measuring unit, at a time of an initial operation before performing an image forming operation.

Abstract: An image forming apparatus includes an image bearing member; a developing device; a transfer member; a contact member provided downstream of the transfer member and upstream of the developing device with respect to a movement direction of a surface of the image bearing member and contacting the image bearing member at a contact portion, wherein the surface of the image bearing member passed through a transfer portion reaches the contact portion without being cleaned, a detecting portion for detecting a size of the sheet; and a controller for executing an operation in a cleaning mode for cleaning the contact member. The controller executes the operation in the cleaning mode when the controller discriminates that the size of the sheet detected by the detecting portion is smaller than a size of the toner image.