An image forming apparatus include a latent image bearer, charger, latent image forming unit, developing unit, receiver unit, transfer unit, information acquisition unit, and correction unit. The charger charges the latent image bearer with a predetermined charging potential. The latent image forming unit forms an electrostatic latent image on the latent image bearer. The developing unit develops the electrostatic latent image to form a toner image. The receiver unit receives the toner image from the talent image bearer. The transfer unit applies a predetermined transfer bias to transfer the toner image to the receiver unit. The information acquisition unit acquires residual image generation determination information. When predetermined residual image generation condition is satisfied, a correction unit corrects image forming condition such that surface potential unevenness of the latent image bearer subsequent to transfer is smaller than that generated where predetermined residual image generation condition is not satisfied.

An image forming apparatus includes a plurality of image carriers, an intermediate transfer body, a plurality of primary transfer members, a secondary transfer member, a first guide member, and a controller. The first guide member guides a recording medium along a conveying direction. The controller controls a primary transfer bias and a secondary transfer bias. A plurality of the primary transfer members include an upstream side primary transfer member and a downstream side primary transfer member. The controller makes an absolute value of the primary transfer bias applied to the downstream side primary transfer member larger than an absolute value of the primary transfer bias applied to the upstream side primary transfer member. The controller lowers an absolute value of the secondary transfer bias when the recording medium separates from the first guide member.

To provide an image forming apparatus capable of suppressing an increase in the cost of a process cartridge and capable of reducing image defects caused by replacement of the process cartridge. A process cartridge including a charging roller and a developing unit is attachable to and detachable from an image forming apparatus. A development temperature sensor is disposed in the developing unit. An in-device temperature sensor is disposed outside the process cartridge inside the image forming apparatus. In the case where a temperature detected by the development temperature sensor is lower than a temperature detected by the in-device temperature-humidity sensor, a peak-to-peak voltage of an alternating-current voltage applied to the charging roller is set based on the result of detection by the development temperature sensor.

An image forming apparatus has: an image supporting member, a charger, a power source unit, an amperometric detector, and a processor. The power source unit applies a plurality of charging voltages, which includes alternating voltages respectively, to the charger sequentially while no print medium is fed. The alternating voltages have different peak-to-peak voltages for a forward discharge range and different peak-to-peak voltages for a reverse discharge range, respectively. The amperometric detector detects values of alternating current flowing in the charger during application of the charging voltages. The processor derives characteristic lines of alternating current value with respect to alternating voltage for the forward discharge range and for the reverse discharge range, respectively, from the values detected by the amperometric detector. The processor derives a peak-to-peak voltage to be used in a process in a different way depending on a difference in slope between the characteristic lines.

When it is judged that a predetermined operation for eliminating a cause for stopping a job is being executed, a following job is restricted from being executed prior to a stopped job. A control method for controlling a job processing apparatus for storing received jobs in a storage unit and sequentially executing the stored jobs includes determining, when a cause for stopping the job to be executed is generated, whether a state in which the cause for stopping the job is not eliminated has continued for a predetermined time, executing, when it is determined that the state in which the cause for stopping the job is not eliminated has continued for the predetermined time, a following job that follows the job is executed prior to the job, judging whether a predetermined operation for eliminating the cause for stopping the job is being executed, and restricting, when it is judged that a predetermined operation for eliminating the cause for stopping the job is being executed, the following job is restricted from being executed prior to the job.

An image forming apparatus according to an embodiment includes a first image forming unit that forms an image on a sheet using a decolorable color material for a decolorable image forming job. A second image forming unit forms an image on a sheet using a non-decolorable color material for a non-decolorable image forming job. A heat source heats the sheet at a control temperature according to a job type. A storage unit includes a job queue that registers jobs in a received order. When a plurality of jobs that differ in the control temperature are registered in the job queue, a controller that changes an execution order of the jobs in the job queue into the ascending order of the control temperature of the heat source, and executes the jobs registered in the job queue according to the changed order.

An image forming apparatus includes an image bearer on which an image is formed; a transfer device to form a transfer portion between the image bearer and the transfer device; a voltage application device to apply a transfer voltage to the transfer device to transfer the image from the image bearer to a transfer target at the transfer portion; an abnormality sensor to detect an abnormal level of the transfer voltage; a temperature sensor to detect an ambient temperature; and a control circuit. The control circuit controls the voltage application device to continue applying the transfer voltage irrespective of whether the abnormality sensor has detected the abnormal level of the transfer voltage when a detection temperature of the temperature sensor is below a predetermined temperature.

An image forming apparatus comprises a paper feeding unit which feeds a sheet-shaped recording medium, an image forming unit which forms a toner image on the recording medium fed from the paper feeding unit, a fixing unit which fixes the toner image formed by the image forming unit on the recording medium, a stacking unit which stacks the recording medium on which the toner image is fixed by the fixing unit, a temperature sensor which detects the surface temperature of the recording mediums stacked on the stacking unit and a control unit which determines, according to the printing information of the recording medium, whether or not to feed a new recording medium from the paper feeding unit when the surface temperature of the recording mediums detected by the temperature sensor is above a threshold temperature.

An image forming apparatus includes an image forming portion for forming form a toner image; an intermediary transfer belt for receiving the toner image; a blade for cleaning the belt by removing residual toner therefrom; an ambient condition sensor for detecting an ambient condition; a memory for storing information relating to a use amount of the belt; a controller for executing an operation in a mode in which a toner is deposited on the belt in a area corresponding to between a preceding sheet and a succeeding sheet during a execution of a continuous image forming job for continuously forming the images on the sheets to supply the toner to the blade, wherein the controller controls a frequency of the operations in the mode, on the basis of a output of the sensor during an image formation job in the information stored in the memory.

According to an embodiment, an image forming apparatus includes an image forming unit that forms an image on a sheet. A heat source heats the sheet at a control temperature according to a job type. A storage unit includes a job queue that registers jobs in a received order. When a plurality of jobs that differ in the control temperature are registered in the job queue, a controller groups the jobs registered in the job queue into job groups according to the control temperature. The controller also changes an execution order of the job groups in the job queue into the ascending order of the control temperature of the heat source, and executes the jobs registered in the job queue according to the changed order.