Storage stores therein a printing rate and an ideal developer supply amount of a developer to be supplied to a development device. The ideal developer supply amount is determined according to the printing rate. A developer amount detection section detects the amount of the developer in the development device. A supply amount detection section detects an actual developer supply amount by detecting the amount of the developer supplied by the developer supply section. A comparison section compares the actual development supply amount with the ideal developer supply amount and outputs first comparison information indicating a result of comparison. An adjusting section adjusts the actual developer supply amount of the developer supply section based on the first comparison information.

An image forming apparatus of an embodiment includes an image forming unit, a waste toner collection container, a paddle motor, and a controller. The controller acquires a replenishment amount for each toner cartridge, when the image forming component is replenished with the toner from the plurality of toner cartridges, sets a coefficient for each replenishment amount of the toner cartridges, at least one of each set coefficient is different from the others, each of the replenishment amount is corrected by each coefficient, and drives the paddle motor according to a cumulative amount of each corrected replenishment amount.

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.

Examples of a print liquid supply unit are described herein. In some examples, the print liquid supply unit includes an electrical interconnect. In some examples, the electrical interconnect is sealed in a supply joint from an outside of the supply unit to an inside of the supply unit. In some examples, the supply joint is welded to join housing components of the supply unit.

According to one embodiment, an image forming apparatus includes a storage portion, a first electrode, a second electrode, a measuring unit, a detected portion, an image forming unit, and a controller. The storage portion stores a recording material. The measuring unit measures a change of capacitance between the first electrode and the second electrode. The detected portion is located inside the storage portion and is capable of moving so that at least one of a distance to the first electrode and a distance to the second electrode changes. The image forming unit forms an image with the recording material. The controller controls supplying of the recording material to the storage portion in response to the change of the capacitance measured by the measuring unit.

An approach is provided for monitoring and reporting capacity of a toner cartridge in a printing device. The printing device determines estimated toner levels based on actual toner levels obtained from a toner sensor of the printing device. The estimated toner levels are determined based on a first actual toner level and a second actual toner level obtained from the toner senor and print usage between the two actual toner levels. The estimated toner levels are determined for levels below the second actual toner level and are mapped to synthetic toner levels. Visual indications of the synthetic toner levels are displayed on the printing device.

When, in a state where a developer borne by a developer bearing member is sandwiched by an opposing portion of an image bearing member and the developer bearing member, C denotes capacitance between the image bearing member and the developer bearing member, ΔV denotes a development contrast, Q/S denotes a charge amount per unit area of the developer borne by the developer bearing member, and Δv denotes a peripheral velocity ratio which is a ratio of a peripheral velocity of the developer bearing member to a peripheral velocity of the image bearing member, a first peripheral velocity ratio is set so that |Q/S×Δv|≤|C×ΔV| is satisfied, and a second peripheral velocity ratio which is larger than the first peripheral velocity ratio is set so that |Q/S×Δv|>|C×ΔV| is satisfied.

Examples of a print liquid supply unit are described herein. In some examples, the print liquid supply unit includes an electrical interconnect. In some examples, the electrical interconnect is sealed in a supply joint from an outside of the supply unit to an inside of the supply unit. In some examples, the supply joint is welded to join housing components of the supply unit.

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.

Example implementations relate to an apparatus to transfer a quantity of print material to a printing device through a transfer mechanism. In some examples, the apparatus includes a container including the quantity of print material, a transfer mechanism associated with the container, and a sensor associated with the transfer mechanism. In some examples, the sensor is to communicate to the printing device information about the transfer of the quantity of print material through the dispenser mechanism.