Abstract: In an image forming apparatus, a sheet is guided into a first conveyor path or a second conveyor path selectively when a first cover is in a closed position, and is ejected onto the first cover when the first cover is in an open position. Upon power-up, a controller causes a first conveyor roller to rotate but if the first cover is in the open position, when a sheet sensor detects a sheet, the controller does not cause a second conveyor roller to rotate, and causes a flapper to swing from a first position to a second position, and when a front end of the sheet reaches a position downstream of an upstream end of the flapper in a conveyance direction of the sheet conveyed by the first conveyor roller, the controller causes the flapper to swing from the second position to the first position.

Abstract: An image forming apparatus includes a photoconductive body, a light source, a deflector to deflect a light beam from the light source, a scanning optical system to image the deflected light beam onto the photoconductive body, a developing unit to supply developer to the photoconductive body, an optical sensor to detect the deflected light beam, a moving mechanism to move the developing unit to a first position and to a second position, and a controller configured to start driving the deflector, when the developing unit is in the second position, the light source to emit the light beam, thereby obtaining a detection signal of the light beam from the optical sensor, and after obtaining the detection signal of the light beam from the optical sensor, control the moving mechanism to move the developing unit to the first position.

Abstract: An image forming apparatus includes a housing, a toner image forming portion, a foil transfer unit, a sheet tray, and a discharge portion. The toner image forming portion is provided in the housing and configured to form a toner image on a sheet. The foil transfer unit is configured to superpose a foil with a surface of the sheet. The sheet tray is installable in the housing in an inserting direction and configured to accommodate a sheet to be supplied to the toner image forming portion. The first discharge portion is configured to discharge the sheet from the foil transfer unit to the outside of the housing in a discharging direction opposite to the inserting direction. The second discharge portion is configured to discharge the sheet from the toner image forming portion to the outside of the housing without passing through the foil transfer unit in the discharge direction.

Abstract: An image forming apparatus according to aspects of the present disclosure includes a cover, an interlocking mechanism, a sensor, a separation mechanism, a controller. In a state where the cover moves from a closed position to an open position while no power is supplied to the controller, a state of the interlocking mechanism changes from a first state to a second state. In a state where the sensor does not detect that the interlocking mechanism is in the second state when power supply to the controller is started, the separation mechanism keeps the developing roller located at a separation position at the separation position. On the other hand, in a state where the sensor detects that the interlocking mechanism is in the second state when power supply to the controller is started, the separation mechanism moves the developing roller located at a contact position to the separation position.

Abstract: A branch frame has a first guide surface and a second guide surface. In a state where a first cover is located at an open position, at least part of the first cover is located in a space through which a fixing device passes when the fixing device is detached from a mount portion, and the fixing device is unattachable to and undetachable from the mount portion through a first opening. In a state where the branch frame is attached to a main housing, at least part of the branch frame is located in the space, and the fixing device is unattachable to and undetachable from the mount portion through the first opening. In a state where the first cover and the branch frame are detached from the main housing, the fixing device is attachable to and detachable from the mount portion through the first opening.

Abstract: An image forming apparatus includes a housing having an opening, a cover configured to openably close the opening, photosensitive drums, cartridges, a first motor and a controller. Each cartridge has a developing roller, a storage chamber configured to store toner, and an agitator configured to agitate the toner. The first motor is configured to rotate the agitators. The controller rotates the agitators by rotating the first motor when forming an image on a sheet. The controller determines whether a new cartridge is included in the plurality of cartridges in response to the image forming apparatus being turned on or in response to the cover being closed. In a case where a new cartridge is included, the controller stirs toner with the agitators by rotating the first motor. In a case where a new cartridge is not included, the controller does not stir the toner.

Abstract: A controller is configured to control a print engine and a conveyor to form an image on both sides of a sheet. The controller is configured to: in a case where images to be formed on both sides of each of an Nth (N is a positive integer) sheet, an (N+1)th sheet, and an (N+2)th sheet are all monochrome image or all color image, convey the (N+2)th sheet to the print engine and form an image before forming an image on both sides of the (N+1)th sheet; and in a case where the images to be formed on both sides of each of the Nth sheet, the (N+1)th sheet, and the (N+2)th sheet are a mixture of the monochrome image and the color image, convey the (N+2)th sheet to the print engine and form an image after forming an image on both sides of the (N+1)th sheet.

Abstract: A controller is configured to: when an inter-sheet time is shorter than or equal to a first time, maintain a developing roller in contact with a photosensitive drum during an inter-sheet time; when the inter-sheet time is longer than the first time and shorter than or equal to a second time longer than the first time, perform, during the inter-sheet time, at least part of temporary separation processing of temporarily separating the developing roller from the photosensitive drum in a state where the photosensitive drum is rotating; and when the inter-sheet time is longer than the second time, perform, during the inter-sheet time, at least part of temporary stop processing of separating the developing roller from the photosensitive drum and then stopping rotation of the photosensitive drum, and subsequently restarting rotation thereof and then bringing the developing roller into contact with the photosensitive drum.

Abstract: An image forming apparatus includes a developing roller, a photo-interrupter, and a separation mechanism. The developing roller is movable between a contact position and a separated position. The photo-interrupter includes a light emitting element and a light receiving element. The separation mechanism includes a cam configured to move the developing roller between the contact position and the separated position. The cam includes a phase detection wall extending in a circumference direction. The phase detection wall has a first slit and a second slit. The first slit allows the light emitted from the light emitting element to pass therethrough when the developing roller is at the separated position. The second slit allows the light emitted from the light emitting element to pass therethrough when the developing roller is at the contact position. A size of the first slit in the circumferential direction is different from that of the second slit.

Abstract: A transfer belt unit for use with an image forming apparatus includes: a transfer belt; and a belt memory. The transfer belt is configured to transfer toner on a photosensitive drum of the image forming apparatus onto a sheet conveyed to a portion between the photosensitive drum and the transfer belt. The transfer belt is also configured to make contact with a cleaning roller of the image forming apparatus and to be cleaned by the cleaning roller. The belt memory includes: a first storage area configured to store therein a first rotation time period indicating a total of a period of time that the cleaning roller rotates at a first rotational speed; and a second storage area configured to store therein a second rotation time period indicating a total of a period of time that the cleaning roller rotates at a second rotational speed faster than the first rotational speed.

Abstract: An image forming apparatus includes a photosensitive drum, a developing roller, a cam, a developing motor, a first transmission mechanism, and a second transmission mechanism. The cam moves the developing roller between a contacting position where the developing roller is in contact with the photosensitive drum and a separated position where the developing roller is separated from the photosensitive drum. The developing motor drives both the developing roller and the cam, and is rotatable in a normal rotating direction and a reverse rotating direction. The first transmission mechanism engages power transmission from the developing motor to the developing roller when the developing motor rotates in the normal rotating direction, and disengages the power transmission when the developing motor rotates in the reverse rotating direction. The second transmission mechanism can engage power transmission from the developing motor to the cam, irrespective of the rotating direction of the developing motor.

Abstract: An image forming apparatus, having a first photosensitive drum, a second photosensitive drum, a first developing roller, a second developing roller, a first moving mechanism, a second moving mechanism, a driving gear, a motor, a first gear train, a second gear train, and a third gear train, is provided. The first gear train having a first gear transmits a driving force from the motor to the first developing roller. The second gear train having a second gear transmits the driving force from the motor to the second developing roller. The second gear train is provided separately from the first gear train. The third gear train having a third gear transmits the driving force from the motor to at least one of the first moving mechanism and the second moving mechanism. The third gear train is provided separately from the first gear train and the second gear train.

Abstract: An image forming apparatus includes: a photosensitive drum; a developing roller; a separation mechanism configured to switch a state of the photosensitive drum and the developing roller between a contact state and a separation state; a main memory storing therein a first rotation number and a second rotation number; and a controller configured to perform calculating a deterioration quantity of the photosensitive drum based on the first rotation number and the second rotation number in the main memory. A surface of the developing roller contacts a surface of the photosensitive drum in the contact state, whereas the surface of the developing roller is separated from the surface of the photosensitive drum in the separation state. The first rotation number is the number of rotations of the photosensitive drum in the contact state, and the second rotation number is the number of rotations of the photosensitive drum in the separation state.

Abstract: An image forming apparatus includes a housing having an opening, a cover configured to openably close the opening, photosensitive drums, cartridges, a first motor and a controller. Each cartridge has a developing roller, a storage chamber configured to store toner, and an agitator configured to agitate the toner. The first motor is configured to rotate the agitators. The controller rotates the agitators by rotating the first motor when forming an image on a sheet. The controller determines whether a new cartridge is included in the plurality of cartridges in response to the image forming apparatus being turned on or in response to the cover being closed. In a case where a new cartridge is included, the controller stirs toner with the agitators by rotating the first motor. In a case where a new cartridge is not included, the controller does not stir the toner.

Abstract: A first transport unit transports, along a first path, a sheet transported from an image forming unit. A second transport unit transports the sheet along a second transport path branched from a junction with the first transport path. A first cover, when open, holds the sheet transported to an exterior of a housing and, when closed, partially constitutes the second transport unit. A flap is disposed at the junction and, when at a first position, blocks the second transport path and guides the sheet along the first transport path and, when at a second position, blocks the first transport path and guides the sheet along the second transport path. A drive unit moves the flap between the first position and the second position. A moving mechanism moves away from the flap in response to closing of the first cover, and pushes and moves the flap to the second position.

Abstract: A controller is configured to, when forming an image on one sheet, in a case where a length of one sheet in a conveyance direction is larger than a first length, drive a moving mechanism to move a plurality of developing rollers from a separation position to a contact position, temporarily stop driving of the moving mechanism, and then, at a first timing, again drive the moving mechanism to move the plurality of developing rollers from the contact position to the separation position; and in a case where the length of the one sheet in the conveyance direction is smaller than or equal to the first length, drive the moving mechanism to move the plurality of developing rollers from the separation position to the contact position and then to move the plurality of developing rollers from the contact position to the separation position without stopping driving of the moving mechanism.

Abstract: A branch frame has a first guide surface and a second guide surface. In a state where a first cover is located at an open position, at least part of the first cover is located in a space through which a fixing device passes when the fixing device is detached from a mount portion, and the fixing device is unattachable to and undetachable from the mount portion through a first opening. In a state where the branch frame is attached to a main housing, at least part of the branch frame is located in the space, and the fixing device is unattachable to and undetachable from the mount portion through the first opening. In a state where the first cover and the branch frame are detached from the main housing, the fixing device is attachable to and detachable from the mount portion through the first opening.

Abstract: An image forming apparatus according to aspects of the present disclosure includes a cover, an interlocking mechanism, a sensor, a separation mechanism, a controller. In a state where the cover moves from a closed position to an open position while no power is supplied to the controller, a state of the interlocking mechanism changes from a first state to a second state. In a state where the sensor does not detect that the interlocking mechanism is in the second state when power supply to the controller is started, the separation mechanism keeps the developing roller located at a separation position at the separation position. On the other hand, in a state where the sensor detects that the interlocking mechanism is in the second state when power supply to the controller is started, the separation mechanism moves the developing roller located at a contact position to the separation position.

Abstract: An image forming apparatus, having first, second, third, and fourth photosensitive drums, first, second, third, and fourth developing rollers, a development-driving gear, a development motor, a first development gear train having a first gear, a second development-gear train having a second gear, a process-driving gear, a process motor, a first process-gear train having a third gear, and a second process gear-train having a fourth gear, is provided. The first development-gear train transmits a driving force from the development motor to the first and second developing rollers. The second development-gear train transmits the driving force from the development motor to the third and fourth developing rollers. The first process-gear train transmits a driving force from the process motor to the first and second photosensitive drums. The second process-gear train transmits the driving force from the process motor to the third and fourth photosensitive drums.

Abstract: An image forming apparatus includes: a first developing roller movable between a first contact position and a first separated position; a second developing roller movable between a second contact position and a second separated position; and a controller. When a sheet interval is shorter than a first interval and is longer than or equal to a second interval, the controller maintains the first developing roller at the first contact position even after the completion of its development for a preceding sheet, controls the first developing roller to start development for a subsequent sheet, moves the second developing roller to the second separated position after the completion of its development for the preceding sheet, moves the second developing roller again to the second contact position, and controls the second developing roller to start development for the subsequent sheet after the second developing roller is moved again to the second contact position.