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.

A protruding portion protruding in a rotation axis direction of an image bearing member is provided at a position between the tip of a separation claw and an apex of the separation claw, when the apex of the separation claw is disposed at a position farthest from the surface of the image bearing member in a direction perpendicular to a straight line connecting the tip and the rotation center of a shaft portion of the separation claw.

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.

An image forming apparatus has a photosensitive member, a plurality of corona chargers configured to charge the photosensitive member by corona discharge, a plurality of charge output circuits configured to output a charging voltage being applied to each of the corona chargers, a plurality of abnormal discharge detection circuits configured to output an abnormal discharge detection signal according to abnormal discharge occurring in each of the corona chargers, and a controller configured to have a common input port connected to the abnormal discharge detection circuits wherein the abnormal discharge detection signal output from each of the abnormal discharge detection circuits is input to the controller through the common input port. Each of the abnormal discharge detection circuits is connected to a corresponding one circuit out of the charge output circuits.

An image forming apparatus includes an apparatus body, a toner cartridge, a replaceable part, an apparatus body memory, and a controller. The replaceable part includes a replaceable part memory storing therein extended-use allowance-and-restriction information. The extended-use allowance-and-restriction information indicates one of allowance information and restriction information. The extended use is defined as use of the replaceable part even after the replaceable part exceeds the remaining life indicated by the life information stored in the apparatus body memory. The apparatus body memory stores life information indicating remaining life of the replaceable part. In a case where the controller determines that the extended-use allowance-and-restriction information indicates the restriction information, the controller is configured to restrict the extended use of the replaceable part. In a case where the controller determines that the extended-use allowance-and-restriction information indicates the allowance information, the controller is configured to allow the extended use of the replaceable part.

An image forming apparatus includes an optical print head, an optical print head moving mechanism, an abutting portion, a projected portion, an opposing portion, and a preventing portion provided on the projected portion so that in a state in which a drum cartridge is dismounted from a main assembly of the image forming apparatus, the preventing portion is contacted to the opposing portion by movement of the optical print head moved by the moving mechanism toward a side downstream of the exposure position with respect to the movement direction and prevents further movement of the optical print head in the movement direction and so that in a state in which the drum cartridge is mounted in the main assembly and the abutting portion contacts the drum cartridge, the preventing portion is in non-contact with the opposing portion.

An image forming apparatus has an openable-closable member, an image carrier, a cover sheet, and a cover moving mechanism. The openable-closable member is arranged in an open position where it keeps a recording medium conveying passage open and in a closed position where it keeps the recording medium conveying passage closed. The cover sheet is reciprocatable between a protection position where it covers the recording medium conveying passage side of the image carrier and a retracted position where it is retracted from the recording medium conveying passage. The cover moving mechanism moves the cover sheet to the retracted position or to the protection position by opening and closing the openable-closable member. Drawing out the cover sheet in the protection position to the recording medium conveying passage side causes the cover sheet to be arranged in a recording medium removal position.

An image forming apparatus includes an optical print head, an optical print head moving mechanism, an abutting portion, a projected portion, an opposing portion, and a preventing portion provided on the projected portion so that in a state in which a drum cartridge is dismounted from a main assembly of the image forming apparatus, the preventing portion is contacted to the opposing portion by movement of the optical print head moved by the moving mechanism toward a side downstream of the exposure position with respect to the movement direction and prevents further movement of the optical print head in the movement direction and so that in a state in which the drum cartridge is mounted in the main assembly and the abutting portion contacts the drum cartridge, the preventing portion is in non-contact with the opposing portion.

A solid lubricant application device includes: a rotating body; a solid lubricant applied to the rotating body; a resilient urging member that causes the solid lubricant to abut toward a circumferential surface of the rotating body; and a guide mechanism that guides movement of the solid lubricant. When a straight line parallel to a direction in which the solid lubricant abuts against the rotating body is referred to as a first straight line, and a straight line parallel to a direction in which the resilient urging member and the solid lubricant are connected is referred to as a second straight line, the guide mechanism guides the movement of the solid lubricant such that an intersecting angle, which is a smaller one of angles formed by the first straight line and the second straight line, decreases as the solid lubricant is applied to the rotating body and accordingly changed in shape.

An image forming apparatus includes a latent image bearer, an intermediate transferor, a primary transferor, a second transferor, and a cleaning blade. The latent image bearer has a surface onto which a lubricant comprising zinc stearate is supplied. The intermediate transferor has a surface onto which the toner image is transferred, the surface including an adhering region to which the lubricant from the latent image bearer adheres. The cleaning blade cleans the surface of the intermediate transferor including the adhering region, after the toner image is secondarily transferred. In a region outside at least a horizontal A4 sheet passing width on the intermediate transferor, a ratio of a peak area derived from zinc stearate to a peak area derived from the intermediate transferor in a difference spectrum between attenuated total reflection (ATR) infrared absorption spectrums of the intermediate transferor in an unused state and after use is 0.892 or less.