A toner level detector, includes: a toner cartridge storing toner and having one side provided with a light-permeable region; an agitator, which is rotatably disposed in the toner cartridge and agitates the toner; a reflective region disposed on an inner surface on the other side of the toner cartridge; a first cleaner disposed on one side of the agitator; a second cleaner disposed on the other side of the agitator; and a transceiver, which is disposed on a body outside the toner cartridge, and outputs an emitting signal to the reflective region through the light-permeable region, wherein the reflective region reflects the emitting signal to generate a reflective signal received by the transceiver through the reflective region, wherein the first cleaner, which is rotating, intermittently cleans the light-permeable region, which is fixed; and the second cleaner, which is rotating, intermittently cleans the reflective region, which is fixed.

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.

An image forming apparatus, including: a photoconductor; a developing device; a developer storage; a supplier configured to supply developer; an optical sensor; and a controller configured to execute: a developing process of developing an electrostatic latent image on the photoconductor; a usage-amount obtaining process of obtaining a usage amount of the developer; a supplying process of supplying the developer to the developing device every time when the obtained usage amount becomes equal to or greater than a first threshold; and a detecting process of detecting, by the optical sensor, an amount of the developer in the developing device every time when the obtained usage amount becomes equal to or greater than a second threshold larger than the first threshold, and wherein the controller is configured to execute the detecting process in a period different from a period in which the developing process is being executed.

A powder transporting device includes: a circulation path that receives and accommodates a developer from multiple toner cartridges filled with the developer, and along which the accommodated developer is transported while circulating; a first supply port that allows the developer to be fed onto the circulation path; a transport path that merges with the circulation path at a portion of the circulation path upstream from the first supply port to allow the developer to be transported therealong into the circulation path; a second supply port through which the developer is fed to the transport path; a detector that detects the developer accommodated in the circulation path; a first transporter that transports the developer in the circulation path at a first transport speed; and a second transporter that extends along the transport path in the circulation path, and that transports the developer into the circulation path at a second transport speed higher than the first transport speed.

A toner supply device for supplying toner to a developing device includes a toner container containing toner to be supplied to the developing device and a remaining amount sensor for detecting the remaining amount of toner in the toner container. The toner container includes a cylindrical rotating container having a spiral conveying rib formed on the inner peripheral surface thereof and a paddle provided so as to be slidable on the inner peripheral surface of the rotating container. The remaining amount sensor detects the remaining amount of toner on the upstream side on or before the contact position of the paddle in the toner conveying direction.

An image forming apparatus includes an apparatus body, a display, a consumable cartridge and a controller. The consumable cartridge is attached to the apparatus body. The consumable cartridge includes a housing and a consumable product memory. The housing accommodates consumable material therein for use in image formation. The consumable product memory stores a first flag. The first flag indicates whether consumable material information indicating that an amount of the consumable material is reduced to a level equal to or less than a first threshold value is displayed or not displayed on the display. The controller is configured to execute a first display process for determining whether the consumable material information is displayed on the display in accordance with indication of the first flag stored in the consumable product memory.

A logic circuitry package for a replaceable print apparatus component comprises an interface to communicate with a print apparatus logic circuit, and at least one logic circuit. The logic circuit may be configured to identify, from a command stream received from the print apparatus, parameters including a class parameter, and/or identify, from the command stream, a read request, and output, via the interface, a count value in response to a read request, the count value based on identified received parameters.

A monitoring device is configured to monitor image recordation by a recorder using a recording material supplied from a first cartridge and a second cartridge. the monitoring device includes a memory and a controller. The controller is configured to obtain number-of-sheet information indicating a number of sheets on which the image recordation has been performed, first consumption amount information indicating a consumption amount of a recording material consumed from the first cartridge, and second consumption amount information indicating a consumption amount of a recording material consumed from the second cartridge, determine ratio information indicating a ratio of the recording material consumed from the second cartridge to a total consumption amount of the recording material consumed from the first and second cartridges based on the obtained first and second consumption amount information, and store the obtained number-of-sheet information and the determined ratio information in the memory.

An image forming apparatus includes: a detection unit configured to detect an amount of developer stored in a developing container and to output remaining amount information; and a control unit configured to perform control, during a replenishment of the developer to the developing container using a replenishment container, to cause a display unit to display a message related to the replenishment. When the replenishment is instructed, the control unit is further configured to perform a first control during the replenishment in a case where the remaining amount information indicates a first remaining amount, and configured to perform a second control different from the first control during the replenishment in a case where the remaining amount information indicates a second remaining amount greater than the first remaining amount.

An image forming apparatus measures, using a toner concentration sensor installed in a developing apparatus of the image forming apparatus, a toner concentration of a developer stored in the developing apparatus to obtain an output waveform. The image forming apparatus calculates, based on the output waveform, a first characteristic value corresponding to a volume of the developer. Based on a result of comparing the first characteristic value with a reference value calculated from a reference output waveform obtained in an initial state of the developing apparatus, the image forming apparatus determines whether to execute a discharge mode for discharging the developer from the developing apparatus and to control an amount of the developer. The image forming apparatus discharges, according to a result of the determining, a portion of the developer from the developing apparatus by controlling a driving speed of the developing apparatus when the discharge mode is executed.