Abstract: An image forming system includes an image forming apparatus, a cutting apparatus, and a controller. The cutting apparatus includes a conveyance path, a first cutting unit configured to cut, at a cutting position with respect to a conveyance direction of the sheet on the conveyance path, the sheet in a width direction perpendicularly intersecting with the conveyance direction, and a second cutting unit configured to cut, at a cutting position with respect to the width direction, the sheet in the conveyance direction. The controller is configured to control the cutting apparatus such that, in a case where the sheet is cut neither with the first cutting unit nor with the second cutting unit, the sheet is conveyed through the conveyance path with the first cutting unit and the second cutting unit retreated not to contact with the sheet passing through the conveyance path.

Abstract: An image forming system includes an image forming apparatus, a cutting apparatus, and a controller. The cutting apparatus includes a conveyance path, a first cutting unit configured to cut, at a cutting position with respect to a conveyance direction of the sheet on the conveyance path, the sheet in a width direction perpendicularly intersecting with the conveyance direction, and a second cutting unit configured to cut, at a cutting position with respect to the width direction, the sheet in the conveyance direction. The controller is configured to control the cutting apparatus such that, in a case where the sheet is cut neither with the first cutting unit nor with the second cutting unit, the sheet is conveyed through the conveyance path with the first cutting unit and the second cutting unit retreated not to contact with the sheet passing through the conveyance path.

Abstract: An image forming system includes an image forming apparatus, a cutting apparatus, and a controller. The cutting apparatus includes a conveyance path, a first cutting unit configured to cut, at a cutting position with respect to a conveyance direction of the sheet on the conveyance path, the sheet in a width direction perpendicularly intersecting with the conveyance direction, and a second cutting unit configured to cut, at a cutting position with respect to the width direction, the sheet in the conveyance direction. The controller is configured to control the cutting apparatus such that, in a case where the sheet is cut neither with the first cutting unit nor with the second cutting unit, the sheet is conveyed through the conveyance path with the first cutting unit and the second cutting unit retreated not to contact with the sheet passing through the conveyance path.

Abstract: A frame of an image forming apparatus, includes: a bottom plate having a bottom face whose shape is substantially quadrangular; a first caster; a second caster; a third caster attached near a second side of the bottom face, the third caster being disposed such that a barycenter of the image forming apparatus is located inside a triangle formed by imaginary lines connecting the first caster, the second caster, and the third caster; and a fourth caster attached to a region outside the triangle, the fourth caster being provided closer to the second side than the barycenter, wherein in a case where the image forming apparatus is installed on the installation face which is flat, the first caster, the second caster, and the third caster are installed on the installation face, and the fourth caster is located away from the installation face.

Abstract: An image forming system includes a first unit, a second unit, and a third unit. The first unit includes an image forming unit that forms an image on a sheet fed from a feed unit. The second unit is arranged on a downstream side of the first unit and includes a cutting unit that cuts the sheet on which the image is formed by the image forming unit. The third unit is arranged on a downstream side of the second unit and includes a post-processing unit that post-processes the sheet cut by the cutting unit. A sheet cut to have a first size is discharged to a first discharge unit provided in the second unit. A sheet cut to have a second size larger than the first size is discharged to a second discharge unit provided in the third unit.

Abstract: A frame of an image forming apparatus, includes: a bottom plate having a bottom face whose shape is substantially quadrangular; a first caster; a second caster; a third caster attached near a second side of the bottom face, the third caster being disposed such that a barycenter of the image forming apparatus is located inside a triangle formed by imaginary lines connecting the first caster, the second caster, and the third caster; and a fourth caster attached to a region outside the triangle, the fourth caster being provided closer to the second side than the barycenter, wherein in a case where the image forming apparatus is installed on the installation face which is flat, the first caster, the second caster, and the third caster are installed on the installation face, and the fourth caster is located away from the installation face.

Abstract: An image forming apparatus forms a plurality of images of different colors on an intermediate transfer belt by a plurality of image forming portions. The image forming apparatus detects a color misregistration amount of the image formed on the intermediate transfer belt and performs image formation using a correction value based on the color misregistration amount. If an elapsed time from previous image formation is less than a predetermined time, the image forming apparatus predicts the correction value using the previous correction value and the temperature at that time and performs color misregistration correction. If the elapsed time from the previous image formation is a predetermined time or longer, the image forming apparatus predicts the correction value using the correction value and the temperature at the time when the elapsed time becomes a predetermined time or longer and performs the color misregistration correction.

Abstract: An image forming system includes an image forming apparatus, a cutting apparatus, and a controller. The cutting apparatus includes a conveyance path, a first cutting unit configured to cut, at a cutting position with respect to a conveyance direction of the sheet on the conveyance path, the sheet in a width direction perpendicularly intersecting with the conveyance direction, and a second cutting unit configured to cut, at a cutting position with respect to the width direction, the sheet in the conveyance direction. The controller is configured to control the cutting apparatus such that, in a case where the sheet is cut neither with the first cutting unit nor with the second cutting unit, the sheet is conveyed through the conveyance path with the first cutting unit and the second cutting unit retreated not to contact with the sheet passing through the conveyance path.

Abstract: An image forming apparatus forms a plurality of images of different colors on an intermediate transfer belt by a plurality of image forming portions. The image forming apparatus detects a color misregistration amount of the image formed on the intermediate transfer belt and performs image formation using a correction value based on the color misregistration amount. If an elapsed time from previous image formation is less than a predetermined time, the image forming apparatus predicts the correction value using the previous correction value and the temperature at that time and performs color misregistration correction. If the elapsed time from the previous image formation is a predetermined time or longer, the image forming apparatus predicts the correction value using the correction value and the temperature at the time when the elapsed time becomes a predetermined time or longer and performs the color misregistration correction.

Abstract: When a mechanism enters a first state, an intermediate transfer member separates from a second photosensitive member. When the mechanism enters a second state, the intermediate transfer member contacts the second photosensitive member. When a first monochrome image is formed on a sheet of a first type by using toner of a first color, the mechanism enters the first state. When a second monochrome image is formed on a sheet of a second type by using toner of the first color, the mechanism enters the second state. A rotation speed of the second photosensitive member for forming the second monochrome image on the sheet of the second type is controlled to a predetermined rotation speed. The predetermined rotation speed is slower than a rotation speed of the second photosensitive member for forming the second image.

Abstract: A bearing, for supporting a rotation shaft of a rotatable member, capable of being supported by a supporting portion provided with an engaging hole engageable with the bearing includes positioning projections having contact surfaces and bearing projections having sliding surfaces on which an outer peripheral surface of the rotation shaft slides. The positioning projections project from different positions so that between adjacent positioning projections, an outer peripheral surface of the bearing and the inner wall surface of the engaging hole form a gap therebetween. The bearing projections project from different positions so that between adjacent bearing projections, an inner peripheral surface of the bearing and an outer peripheral surface of the rotation shaft form a gap therebetween. With respect to a circumferential direction of the rotation shaft, the positioning projections and the bearing projections are provided at positions different from each other.

Abstract: An image forming apparatus includes a detection unit, a supporting portion, a shutter, an opposing portion, and a regulating portion. The shutter is configured to move between a first position and a second position with respect to the supporting portion. The second position is a position where an opening portion retracts from a detection surface of the detection unit and the shutter covers the detection surface. The regulating portion comprises a wall portion that protrudes from the opposing portion toward the shutter and that contacts an edge portion of the opening portion when the shutter is positioned at the second position. The wall portion is extending from a first end side to a second end side of the opening portion with respect to a width direction intersecting with an opening and closing direction of the shutter.

Abstract: When a mechanism enters a first state, an intermediate transfer member separates from a second photosensitive member. When the mechanism enters a second state, the intermediate transfer member contacts the second photosensitive member. When a first monochrome image is formed on a sheet of a first type by using toner of a first color, the mechanism enters the first state. When a second monochrome image is formed on a sheet of a second type by using toner of the first color, the mechanism enters the second state. A rotation speed of the second photosensitive member for forming the second monochrome image on the sheet of the second type is controlled to a predetermined rotation speed. The predetermined rotation speed is slower than a rotation speed of the second photosensitive member for forming the second image.

Abstract: A bearing, for supporting a rotation shaft of a rotatable member, capable of being supported by a supporting portion provided with an engaging hole engageable with the bearing includes positioning projections having contact surfaces and bearing projections having sliding surfaces on which an outer peripheral surface of the rotation shaft slides. The positioning projections project from different positions so that between adjacent positioning projections, an outer peripheral surface of the bearing and the inner wall surface of the engaging hole form a gap therebetween. The bearing projections project from different positions so that between adjacent bearing projections, an inner peripheral surface of the bearing and an outer peripheral surface of the rotation shaft form a gap therebetween. With respect to a circumferential direction of the rotation shaft, the positioning projections and the bearing projections are provided at positions different from each other.

Abstract: When a mechanism enters a first state, an intermediate transfer member separates from a second photosensitive member. When the mechanism enters a second state, the intermediate transfer member contacts the second photosensitive member. When a first monochrome image is formed on a sheet of a first type by using toner of a first color, the mechanism enters the first state. When a second monochrome image is formed on a sheet of a second type by using toner of the first color, the mechanism enters the second state. A rotation speed of the second photosensitive member for forming the second monochrome image on the sheet of the second type is controlled to a predetermined rotation speed. The predetermined rotation speed is slower than a rotation speed of the second photosensitive member for forming the second image.

Abstract: When a mechanism enters a first state, an intermediate transfer member separates from a second photosensitive member. When the mechanism enters a second state, the intermediate transfer member contacts the second photosensitive member. When a first monochrome image is formed on a sheet of a first type by using toner of a first color, the mechanism enters the first state. When a second monochrome image is formed on a sheet of a second type by using toner of the first color, the mechanism enters the second state. A rotation speed of the second photosensitive member for forming the second monochrome image on the sheet of the second type is controlled to a predetermined rotation speed. The predetermined rotation speed is slower than a rotation speed of the second photosensitive member for forming the second image.

Abstract: An image forming apparatus is designed to be capable of easily suppressing a variation of an inclination of a sensor relative to an endless belt and capable of high accuracy and stabilized sensing operation. The image forming apparatus includes a belt unit having an endless belt supported to be rotatable in a circumferential direction, an image forming unit for forming an image on the belt unit, and an optical sensor for detecting light projected onto the endless belt. The image forming apparatus further includes a sensor supporting member for supporting the sensor, and a positioning portion including, as a unit, a first positioning portion for positioning the belt unit by being contacted by the belt unit and a second positioning portion positioning the sensor supporting member by being contacted by the sensor supporting member.

Abstract: An image forming apparatus includes a transfer portion transferring a toner image onto a sheet, a fixing portion fixing the toner image which has been transferred by the transfer portion onto the sheet by using heat, a discharge path guiding the sheet on which the toner image has been fixed by the fixing portion to a discharge port, a branch path branched from the discharge path, a rotator pair providing on the branch path and conveying the sheet, and a control portion configured to rotate the rotator pair while consecutively discharging the sheets to the discharge port through the discharge path without passing through the branch path.

Abstract: Provided is an image forming apparatus that forms an image on a recording material, the apparatus including: a first helical gear and a second helical gear that are engaged with each other; and a driving portion that applies a driving force to the first helical gear, wherein at least one of the first helical gear and the second helical gear is a helical gear in which torsional rigidity in a tooth width direction of one side end in a width direction of the gear is larger than torsional rigidity in a tooth width direction of the other side end, and wherein a twist direction of helical teeth and a rotational direction of the first helical gear due to the driving portion are set such that the other side end is engaged earlier than the one side end.

Abstract: Provided is an image forming apparatus that forms an image on a recording material, the apparatus including: a first helical gear and a second helical gear that are engaged with each other; and a driving portion that applies a driving force to the first helical gear, wherein at least one of the first helical gear and the second helical gear is a helical gear in which torsional rigidity in a tooth width direction of one side end in a width direction of the gear is larger than torsional rigidity in a tooth width direction of the other side end, and wherein a twist direction of helical teeth and a rotational direction of the first helical gear due to the driving portion are set such that the other side end is engaged earlier than the one side end.