An image-forming apparatus includes a photosensitive drum, a development member, an intermediate transfer belt, a transfer member, a transfer voltage, a density detection unit, a temperature detection unit, and a control unit. The development member forms a toner image on a surface of the photosensitive drum, which the transfer member transfers to the intermediate transfer belt. The density detection unit detects an information related to a density of the toner image transferred to the intermediate transfer belt. The control unit controls a driving speed of the intermediate transfer belt. In a detection operation in which the density detection unit detects the information related to the density of the toner image transferred to the intermediate transfer belt in a state where the transfer voltage is applied to the transfer member, the control unit controls the driving speed based on an ambient temperature detected by the temperature detection unit.

An image forming apparatus, temperature control method, and temperature control device are provided. The apparatus includes the device, which acquires a first temperature difference between a temperature estimation value of a fixer, which is obtained by simulating a member temperature of a temperature control target serving as a heat capacitor-resistor circuit at an initial stage of operation of the fixer, and a detected temperature detected by a temperature sensor, and acquires a second temperature difference between a temperature estimation value of the fixer, which is obtained during an operation after the first temperature difference is acquired, and a detected temperature. The device calculates a difference between the first temperature difference and the second temperature difference, determines that the detected temperature is abnormal in response to the difference being equal to or greater than a threshold value, and performs temperature control for correcting a target temperature of the member temperature.

An image forming apparatus includes an image former that forms a color image by superimposing images of respective colors formed on respective different photoconductors on an intermediate transfer body, the image former continuously forming color images of pages on one continuous paper, and the image forming apparatus includes: a first hardware processor that performs job management for each color and generates print job data in which a margin region having a first width is set on an upstream or a downstream in a sheet passing direction of an image forming region of each page; a second hardware processor that detects a color shift amount of each color of the image forming region; and a third hardware processor that corrects a formation position of the image forming region to be a print target page next on the print job data for a color in which a color shift has occurred.

An image forming apparatus includes an image forming unit, a fixer, first and second temperature sensors, and storage and control units. The fixer fixes an image formed on the sheet by pressing. The first temperature sensor is disposed away from the image forming unit and the fixer, and measures an ambient temperature. The second temperature sensor is disposed closer to the image forming unit than the first temperature sensor, and measures an ambient temperature. The storage unit stores one or more difference values between first and second temperatures measured by the first and second temperature sensors when a switching condition is satisfied. When a difference between the one or more difference values in the storage unit and a latest difference value is equal to or larger than a threshold, the control unit stores information indicating that a reference value for determining an abnormality is exceeded.

A fixing device includes a heating rotating member and a pressure rotating member and performs image formation in one mode out of a plurality of modes including a first mode and a second mode. A time during which one of the heating rotating member and the pressure rotating member moves between an abutment position and a separation position in a case where the image formation is performed in the first mode is a first time, a time during which the one moves between the abutment position and the separation position in a case where the image formation is performed in the second mode is a second time, and the first time is shorter than the second time.

An image forming apparatus includes an image bearing member, a transfer member, an acquiring portion, an applying portion, and a controller. When a transfer voltage is subjected to constant-voltage control so that the transfer voltage applied to the transfer member by the applying portion is substantially constant, in a case that the transfer voltage, when a toner amount used for a toner image is a first toner amount, is a first voltage, the controller controls the applying portion so that the transfer voltage is a second voltage lower in absolute value than the first voltage in a case that the toner amount is a second toner amount greater than the first toner amount. The acquiring portion acquires toner amount information on the toner amount for each toner image transferred onto a single recording material.

An image forming apparatus includes an image bearing member, a transfer member, an acquiring portion, an applying portion, and a controller. When a transfer voltage is subjected to constant-voltage control so that the transfer voltage applied to the transfer member by the applying portion is substantially constant, in a case that the transfer voltage when a toner amount used for a toner image is a first toner amount is a first voltage, the controller controls the applying portion so that the transfer voltage is a second voltage smaller lower in absolute value than the first voltage in a case that the toner amount is a second toner amount ager greater than the first toner amount. The acquiring portion acquires toner amount information on the toner amount for each toner image transferred onto a single recording material.

An image forming apparatus includes a forming unit, a transfer unit, a blowing unit, a temperature detection unit, and a control unit. The forming unit forms a toner image on a photosensitive member. The transfer unit transfers the formed toner image onto a recording material. The blowing unit takes outside air into the apparatus to generate an air flow for adjusting a temperature of the transfer unit. The temperature detection unit detects an ambient temperature outside the apparatus. The control unit controls driving of the blowing unit based on the detected ambient temperature. The control unit drives the blowing unit in a case where the detected ambient temperature is less than or equal to a first temperature threshold and a gradient value indicating a change in the detected ambient temperature is at least a first gradient threshold.

An image forming apparatus includes an image forming portion, a heating portion that includes a heating element which is heated by power from a power supply and heats an image, a temperature detecting portion that detects temperature of the heating portion, and a power control portion that controls power supplied to the heating element based on information from the temperature detecting portion. The image forming apparatus further includes a detecting portion that detects whether voltage from the power supply exceeds a rated value, and when the detecting portion detects that the voltage from the power supply exceeds the rated value, the power control portion controls the power supply such that a waveform pattern of an electric current to the heating element in one control cycle becomes a waveform pattern of phase control, where power supplying time to the heating element in one half wave becomes a predetermined time or less.

An image forming apparatus controls the number of rotations of a photosensitive drum based on information related to the use of the photosensitive drum and a suspension time in a rotation operation of rotating the photosensitive drum after a lapse of the suspension time between a first image forming operation of forming an image on a transfer material and a second image forming operation performed after the first image forming operation.