An image forming apparatus includes an image bearing member, a transfer portion configured to transfer an image borne on the image bearing member to a sheet, a current detection portion configured to detect a current flowing through the transfer portion, a conveyance portion configured to convey the sheet to the transfer portion, a driving portion configured to drive the conveyance portion, and a controller configured to acquire an arrival timing at which a leading edge of a preceding sheet has arrived at the transfer portion based on a detection result of the current detection portion, and control the driving portion in response to the arrival timing in a state where a succeeding sheet that follows the preceding sheet is conveyed by the conveyance portion.

Provided is an image forming apparatus including a positioning portion provided upstream of a transfer portion in a transport direction of a recording medium. The positioning portion positions the medium using a leading end of the medium. Additionally included is a detector that is disposed downstream of the positioning portion in the transport direction, and that detects passage of the leading end of the medium; and a controller that controls a transport speed in a period from when the leading end of the medium passes through the detector to when the leading end of the medium passes through a target position situated downstream of the detector in the transport direction, in accordance with a time since transport of the medium is started from the positioning portion until the leading end of the medium passes through the detector.

An image-forming apparatus includes a photosensitive drum, a developing roller, a cam, a switching mechanism, a sheet tray, a sheet feed mechanism, a sheet sensor, and a controller. The switching mechanism rotates the cam to move the developing roller from a contact position in contact with the photosensitive drum to a separated position away from the photosensitive drum after development for the first sheet, if feeding of a second sheet is not started after elapse of a prescribed time period since detection of a first sheet. If image data for the second sheet is ready and upon elapse of a predetermined standby time period from elapse of the prescribed time period, the sheet feed mechanism starts feeding the second sheet toward the photosensitive drum and the switching mechanism rotates the cam to move the developing roller to the separated position in accordance with conveyance of the second sheet.

The present invention provides an image forming apparatus that reduces image artifacts caused by the back tension of a separating unit. A control unit decreases the number of rotations (the rotational speed) of a resist roller pair after the leading edge of a sheet reaches a transfer position.

An image forming unit forms an image based on image data. A roller conveys the sheet from a tray. A reading unit reads the sheet. A controller controls the image forming unit to form a test image on one side of the sheet, controls the roller to convey the sheet on which the test image has been formed, obtains first read data relating to a read result of a first surface of the sheet on which the test image is formed, obtains second read data relating to a read result of a second surface from the first read data and the second read data, selects read data relating to a read result relating to the test image, controls, based on the selected read data, a density of an output image to be formed by the image forming unit.

An image forming apparatus includes an image forming unit to form an image on a sheet conveyed from a sheet storing unit by a sheet conveying unit, and a registering unit that registers detected sheet thickness information and detected sheet surface characteristics information. Based on information, distinct front and back surfaces of a conveyed predetermined sheet and a type of the conveyed predetermined sheet is determined. If the predetermined sheet type matches a type of an upcoming sheet on which the image will be formed and the determined front and back surfaces matches front and back surfaces of the upcoming sheet, an image is formed on the predetermined sheet. If the predetermined sheet type matches the upcoming sheet type and the determined front and back surfaces do not match the upcoming sheet front and back surfaces, information is displayed conveying that the predetermined sheet front and back surfaces are inverted.

Provided is an image forming apparatus including a positioning portion provided upstream of a transfer portion in a transport direction of a recording medium. The positioning portion positions the medium using a leading end of the medium. Additionally included is a detector that is disposed downstream of the positioning portion in the transport direction, and that detects passage of the leading end of the medium; and a controller that controls a transport speed in a period from when the leading end of the medium passes through the detector to when the leading end of the medium passes through a target position situated downstream of the detector in the transport direction, in accordance with a time since transport of the medium is started from the positioning portion until the leading end of the medium passes through the detector.

A paper guide member includes plural thread-shaped protrusions extending in a passing direction of paper to guide the paper after a toner image is transferred so that the paper passes with a distance secured from a static eliminator that eliminates static electricity in proximity to the paper in a width direction of the paper. The plural thread-shaped protrusions adjoin each other across a slit in the width direction of the paper. The plural thread-shaped protrusions include first thread-shaped protrusions each having a height at which the paper is supported and guided, and second thread-shaped protrusions each having a height smaller than the height of each of the first thread-shaped protrusions and present in regions on an outer side of both ends in the width direction of each passing region where paper having each width passes.

An image forming apparatus includes a controller that receives a print job, which includes the sheet type and print settings of simplex printing or duplex printing. A sheet stacked on a feeding unit is discharged to a discharge portion with an upper surface of the sheet facing different directions in duplex printing and in simplex printing in a first mode, and the sheet stacked on the feeding unit is discharged to the discharge portion with the upper surface of the sheet facing the same direction in the duplex printing and in the simplex printing in a second mode.

An image forming apparatus includes an image bearing member, a transfer portion configured to transfer an image borne on the image bearing member to a sheet, a current detection portion configured to detect a current flowing through the transfer portion, a conveyance portion configured to convey the sheet to the transfer portion, a driving portion configured to drive the conveyance portion, and a controller configured to acquire an arrival timing at which a leading edge of a preceding sheet has arrived at the transfer portion based on a detection result of the current detection portion, and control the driving portion in response to the arrival timing in a state where a succeeding sheet that follows the preceding sheet is conveyed by the conveyance portion.