An image forming apparatus includes a main body housing, a first cartridge to store first developer, a second cartridge to store second developer, a first temperature sensor to detect an inside temperature as a temperature inside the main body housing, and a controller configured to calculate a first control temperature corresponding to the first cartridge, using the detected inside temperature and a first coefficient to be multiplied by the inside temperature, calculate a second control temperature corresponding to the second cartridge, using the detected inside temperature and a second coefficient to be multiplied by the inside temperature, the second coefficient being different from the first coefficient, and perform cooling control to cool an inside of the main body housing when at least one selected from the first control temperature and the second control temperature is higher than a particular threshold.

A motor control apparatus excites an excitation phase targeted for excitation among a plurality of excitation phases of a motor. The motor control apparatus, in a state in which a rotor of the motor is stopped, excites an excitation phase corresponding to a stop position of the rotor among the plurality of the excitation phases, and measures a physical quantity which changes in accordance with an inductance of at least one of a plurality of coils configuring the plurality of excitation phases. The motor control apparatus estimates a temperature of the rotor from a measurement value of the measured physical quantity, and decides a parameter value for control of the motor based on the estimated temperature.

An image forming apparatus includes an image bearer, a developing device, a fixing device, and circuitry. The developing device contains a developer and develops a latent image on the image bearer with the developer. The developing device includes a stirrer to stir the developer. The fixing device fixes a toner image onto a sheet. The circuitry performs start-up operations after receiving a print start command and before starting a printing operation. The start-up operations includes starting a warm-up operation of the fixing device and starting, during the warm-up operation, a stirring operation in which the stirrer stirs the developer.

An image forming apparatus includes a tray which is movable between a housed position at which the tray is housed in a housing portion of a body and a drawn-out position, a first cartridge detachably attached to the tray and including a first developing roller, and a second cartridge detachably attached to the tray and including a second developing roller. In a contacting state where (i) the first cartridge and the second cartridge are attached to the tray, (ii) the tray is in the housed position, (iii) the first developing roller contacts a first photosensitive drum, and (iv) the second developing roller contacts a second photosensitive drum, a position of a first projection of the first cartridge and a position of a first holder to which a first memory is fixed at least partially overlap each other with respect to the vertical direction.

An image forming apparatus comprising: an acceptance section; a prediction section which predicts, based on margin information contained in an instruction for execution of an accepted job, an arrangement pattern of a plurality of sheets to be obtained by the execution; a determination section which determines, based on the margin information, whether or not a sum of respective areas of margin regions of the plurality of sheets is greater than a threshold associated with the predicted arrangement pattern; and an adjusted printing section which downscales, in response to a determination that the sum is greater than the threshold, an overall image consisting of a set of partial images intended to be formed and arranged in the predicted arrangement pattern, in such a manner as to fall within one or more sheets arranged in an altered arrangement pattern, and forms the downscaled image on the one or more sheets.

An image formation apparatus according to one or more embodiments includes: an engagement part to which a replacement unit with a first communication part is detachably attachable; a second communication part configured, in a state where the replacement unit is attached to the engagement part, to communicate wirelessly with the first communication part of the replacement unit; and a control unit programmed to control the second communication part. In a process of causing the second communication part to communicate wirelessly with the first communication part a plurality of times, the control unit detects a change in a response from the first communication part.

An angle estimator includes correction means for correcting a phase of an error parameter to obtain a corrected error parameter and estimation means for calculating an estimated speed and an estimated angle of the motor based on the corrected error parameter. The error parameter is a function of an angle error representing a difference between an actual angle and an estimated angle of a motor.

An example method of controlling a printing process in accordance with aspects of the present disclosure includes controlling an optical density of a printed image such that the optical density is increased for a predetermined portion of a leading edge of a page.

Provided is an image forming apparatus capable of reducing a downtime for switching between a monochrome image forming mode and a color image forming mode. In the image forming apparatus, images formed by a plurality of image forming stations are transferred in superimposition onto a transfer member. Further, the image forming apparatus controls image formation in each of a first mode of performing image formation using only an image forming station located at the most downstream position in a moving direction of the transfer member among the plurality of image forming stations, and a second mode of performing image formation using the plurality of image forming stations.

An image forming apparatus includes an image bearing drum; a drum charging member at a charging position opposed to the drum, with a charging bias; a developing member for developing an electrostatic image formed on the drum with toner, with a developing bias; a transfer member for transferring a toner image from the drum onto a sheet, with a transfer bias; a transfer bias source for outputting transfer bias; and a controller for effecting control to start raising of the transfer bias so as to correspond to timing at which an area of the drum passing at a timing of starting of raising of the charging bias passes the transfer position and to complete the raising of the transfer bias so as to correspond to timing at which an area of the drum passing at a timing of completion of raising of the charging bias passes the transfer position.