A sensor unit includes a first movable member including a member-to-be-detected, a sensor, and a second movable member. When a sheet is normally fed, the first movable member is in a first position, the member-to-be-detected is in a first phase, the second movable member is in a second position, and a functional/non-functional state of the member-to-be-detected is one state. When the sheet is not fed and the first movable member is in a second position, the member-to-be-detected is in the first phase, the second movable member is in a third position, and the functional/non-functional state is the other state. When the first movable member is in the first position and the second movable member is in a fourth position, by movement of the member-to-be-detected to a second phase, the functional/non-functional state is changed from the one state to the other state and an output of the sensor changes.

An image forming apparatus includes a drum cartridge and a controller. The drum cartridge includes a photosensitive drum, a charger and a drum cartridge memory storing a life count value and discharge history information. The controller includes a voltage applying circuit, and an abnormal discharge detection circuit. In a case where the abnormal discharge detection circuit detects an abnormal discharge, the controller does not permit printing in a case where the life count value is equal to or more than a first reference value and a number of abnormal discharges which is included in the discharge history information read from the drum cartridge memory is equal to or more than a particular threshold value, or permits printing in a case where the life count value is equal to or more than the first reference value and the number of abnormal discharges is less than the particular threshold value.

An image forming apparatus includes an image forming part, a canceling processing part, a first switching processing part and a second switching processing part. The canceling processing part is performable an image canceling operation where a toner image formed on an intermediate transferring member is removed from the intermediate transferring member without transferred to a sheet. The first switching processing part is capable of switching a printing mode in the image forming part between a plurality of printing modes having different printing conditions in the image forming part, based on an image data under waiting for printing and a predetermined first switching condition. The second switching processing part is capable of switching the printing mode based on the image data under waiting for printing and a predetermined second switching condition when the image canceling operation is performed.

An image forming apparatus includes an image forming part, a toner storage part, a toner conveyance part, a drive motor and a control part. The image forming part forms an image on a sheet using a toner. The toner storage part stores the toner replenished to the image forming part. The toner conveyance part conveys the toner. The drive motor generates a drive force by which the toner conveyance part conveys the toner. The control part generates a control signal for controlling the drive motor, based on information showing a rotational speed of the drive motor. The control part executes a determination processing for determining whether a driving of the drive motor is stopped, based on the control signal.

An image forming apparatus includes a paper transport unit, an image forming unit, a reading unit, a foreign matter detection signal generation circuit, and a foreign matter detection control circuit. The foreign matter detection signal generation circuit generates a first foreign matter detection signal, based on an analog image signal to be output from a line sensor. In foreign matter detection processing, when a pixel that reads foreign matter continues by a specific first consecutive number or more in a signal based on the analog image signal of each pixel to be output from the line sensor, the foreign matter detection signal generation circuit sets a level of the first foreign matter detection signal to a level indicating the presence of foreign matter.

A printer including a transport path; a transport mechanism that is disposed in the transport path and transports the medium in a transporting direction caused when printing is executed by a recording section; a discharge-side transport path that forms a part of a downstream side in the transporting direction from the recording section in the transport path and is movable to a position close to the transport mechanism and a position separated from the transport mechanism; and a control section that controls the recording section and the transport mechanism. In a state where a transport failure of the medium occurs in the transport path, in a case where a predetermined condition is satisfied, the control section executes an additional transport process of discharging the medium to the discharge-side transport path by transporting the medium in the transporting direction by a predetermined amount by the transport mechanism.

A fixing device (7) includes a fixing member (21), a pressing member (22), a rotation detector (41), and an auxiliary driving part (42). The fixing member (21), with rotating around an axis, heats a toner image on a medium (S). The pressing member (22), with rotating around an axis, forms a pressing area (N) with the fixing member (21) and presses toner on the medium (S) passing through the pressing area (N). The rotation detector (41), when the medium (S) stops while being sandwiched between the fixing member (21) and the pressing member (22), detects rotation of the fixing member (21) or the pressing member (22) generated in a process of extracting the medium (S) toward an upstream side or a downstream side in a passing direction. The auxiliary driving part (42), while the medium (S) is being extracted, determines a rotating direction of the fixing member (21) or the pressing member (22) based on a detection result by the rotation detector (41), and rotates the fixing member (21) or the pressing member (22) in the rotating direction.

An energization controlling portion selectively controls energization of a plurality of heat generating elements so that electric power to be supplied to the heat generating elements to heat a non-image heating region, through which an image formed on a recording material does not pass, among a plurality of heating regions of an image heating portion, is smaller than electric power to be supplied to the heat generating elements to heat an image heating region, through which the image passes, among the plurality of heating regions. When an abnormality detecting portion detects an abnormality in an image forming apparatus, the energization controlling portion increases the electric power to be supplied to the heat generating elements to heat the non-image heating region.

A conveying device includes a rotating carrier, an inlet rotary body, an outlet rotary body, a downstream conveyor, and an inching controller. The rotating carrier carries a sheet. The inlet rotary body transfers the sheet to the rotary carrier from upstream of the rotary carrier in a conveyance direction of the sheet. The outlet rotary body transfers the sheet to a downstream area from the rotary carrier in the conveyance direction. The downstream conveyor conveys the sheet downstream from the outlet rotary body in the conveyance direction. The inching controller performs an inching operation to convey the sheet on a conveyance path including at least the downstream conveyor. The inching controller causes at least the outlet rotary body and the downstream conveyor to perform a conveying operation in conjunction with each other in the inching operation.

An image forming apparatus includes a drum cartridge and a controller. The drum cartridge includes a photosensitive drum, a charger and a drum cartridge memory storing a life count value and discharge history information. The controller includes a voltage applying circuit, and an abnormal discharge detection circuit. In a case where the abnormal discharge detection circuit detects an abnormal discharge, the controller does not permit printing in a case where the life count value is equal to or more than a first reference value and a number of abnormal discharges which is included in the discharge history information read from the drum cartridge memory is equal to or more than a particular threshold value, or permits printing in a case where the life count value is equal to or more than the first reference value and the number of abnormal discharges is less than the particular threshold value.