A drum unit includes a photosensitive drum, a developing unit, a toner cartridge, a connector and a relay board. The photosensitive drum is rotatable about a first axis extending in an axial direction. The developing unit includes a magnetic roller, a developer container, a conveyer member and a toner sensor. The developer container accommodates therein carrier, and has an inlet. The conveyer member is positioned in the developer container, and configured to convey toner and the carrier from the inlet toward the magnetic roller. The toner cartridge accommodates therein toner and is attachable to the developer container to replenish toner in the developer container through the inlet. The connector is electrically connected to an image forming apparatus. The relay board electrically connects the toner sensor to the connector. The relay board is configured to transmit a detection signal from the toner sensor to the image forming apparatus.

A transform wrapper is stored on a memory device and the memory device may be included in a printer cartridge. The transform wrapper may dynamically build a transform map for a printer based on metadata stored at the memory device. The metadata may indicate at least one of a type of depositing material, transform map, print media and printer.

In an image forming apparatus a toner cartridge includes a toner memory storing toner identification information. The toner cartridge is detachably attachable to a drum cartridge. The drum cartridge includes a drum memory storing drum identification information. The drum cartridge is detachably attached to the main-body casing. A controller performs a request process to request execution of a density correction process to correct a density of developer, in a case where a toner identification information determination process determines that the toner identification information stored in the toner memory does not match the toner identification information which is stored in the main-body memory in a toner identification information storing process or a drum identification information determination process determines that the drum identification information stored in the drum memory does not match the drum identification information which is stored in the main-body memory in the drum identification information storing process.

In an image forming apparatus, a controller performs processes in accordance with an operation mode settable to one of a first subscription mode and a second subscription mode. The first subscription mode corresponds to a first subscription in which a specific-color cartridge is a subscription subject and a non-specific-color cartridge is not the subscription subject. The second subscription mode corresponds to a second subscription in which both the specific-color cartridge and the non-specific-color cartridge are the subscription subject. The controller performs restricting usage of the non-specific-color cartridge in a case where the first subscription mode is set as the operation mode and the type information of the non-specific-color cartridge indicates the subscription type, compared to a case where the second subscription mode is set as the operation mode and the type information of the non-specific-color cartridge indicates the subscription type.

A cartridge includes: a housing; a storage medium having an electrical contact surface; and a holder movable relative to the housing. The holder includes a first holder member and a second holder member movable relative to the first holder member. The first holder member includes at least one pawl and holds the electrical contact surface at one end surface of the first holder member in a first direction crossing the electrical contact surface. The second holder member includes at least one corner part engageable with the at least one pawl to provide an engaging portion therebetween. The second holder member has a through-hole that is open at another end face of the second holder member in the first direction. The engaging portion is accessible from an outside of the holder through the through-hole.

Provided is a method for removing a first holder member from a second holder member in a cartridge. The cartridge includes: a housing; the first holder member holding an electrical contact surface; and the second holder member supported by the housing. The first holder member includes a pawl, and the second holder member includes a corner part engageable with the pawl of the first holder member. The electrical contact surface is held at one end surface of the first holder member in a first direction crossing the electrical contact surface. The method includes: disengaging the pawl from the corner part; and separating the housing and the second holder member from the first holder member in the first direction away from the one end surface of the first holder member.

An image forming apparatus includes an apparatus body, a cover, a cartridge, and a controller. The cartridge includes a second memory storing lifetime information indicating lifetime of the cartridge and identification information unique to the cartridge. In a case where the lifetime information indicates the initial value for the lifetime, the controller is configured to perform setting the cartridge to be usable in the image forming apparatus. In a case where the controller determines that the lifetime information does not indicate the initial value for the lifetime of the cartridge, the controller is configured to perform judging whether the identification information stored in the second memory matches a registration identification information stored in a first memory of the apparatus body. In a case where the identification information matches the registration identification information, the controller is configured to perform determining that the cartridge is usable for the image forming apparatus.

An image forming apparatus includes a developing cartridge, a main memory and a controller. The controller is configured to perform determining whether the developing cartridge is reached a lifetime on a basis of: at least one of s developing maximum printable number of sheets which corresponds to developing identification information, a maximum developing roller rotation number which corresponds to the developing identification information, and a maximum dot count which corresponds to the developing identification information; and at least one of a developing cumulative number of printed sheets, a cumulative developing roller rotation number and a cumulative dot count.

According to one example, an image forming apparatus includes a detection unit that detects temperature information on a temperature of a toner stored in a toner cartridge, an image forming unit that forms a toner image on a sheet with the toner supplied from the toner cartridge, a fixing unit that fixes the toner image formed on the sheet by the image forming unit, and a control unit that controls a fixing temperature in the fixing unit according to the temperature information detected by the detection unit and an accumulated time in which the temperature information is detected.

A cartridge includes: a housing; a storage medium having an electrical contact surface; and a holder movable relative to the housing. The holder includes a first holder member. and a second holder member movable relative to the first holder member. The first holder member includes at least one pawl and holds the electrical contact surface at one end surface of the first holder member in a first direction crossing the electrical contact surface. The second holder member includes at least one corner part engageable with the at least one pawl to provide an engaging portion therebetween. The second holder member has a through-hole that is open at another end face of the second holder member in the first direction. The engaging portion is accessible from an outside of the holder through the through-hole.