An image forming apparatus includes a reverse roller pair including a drive roller and a driven roller by which a recording medium is nipped and conveyed reversibly, a motor configured to rotate the drive roller reversibly, a conveyance roller pair, a detection unit configured to detect the recording medium conveyed by the conveyance roller pair, and a controller configured to control the motor, in a case in which the recording medium is detected by the detection unit, to cause the drive roller to rotate in a first rotation direction by a first rotation amount, thereafter to cause the drive motor to rotate in a second rotation direction by a second rotation amount. A difference between the first rotation amount and the second rotation amount is set to an integer multiple of a predetermined rotation amount of the motor, the predetermined rotation amount making the drive roller one rotation.

An edge position detecting apparatus includes a light emitting device, a detecting device, and a calculating circuit. The light emitting device includes a plurality of light sources with different emission wavelengths. The light emitting device irradiates a conveyed object with linear light along a width direction of the conveyed object, the width direction being perpendicular to a conveying direction of the conveyed object. The detecting device detects, at a plurality of positions in the width direction of the conveyed object, intensity of reflected light of light emitted by the light emitting device. The calculating circuit calculates, based on a detection result of the detecting device, a position of an edge of the conveyed object in the width direction.

An image forming apparatus for forming an image on a sheet, includes an image forming unit configured to form the image on the sheet, a double-sided conveyance path through which the sheet with the image formed on a first surface passes before the image forming unit forms an image on a second surface opposite to the first surface, a guide member having a contact portion configured to contact one end of the sheet in the width direction of the sheet, the guide member being provided on the double-sided conveyance path, and a reversing roller pair forwardly and reversely rotatable, configured to convey the sheet to the double-sided conveyance path during a reverse rotation, the reversing roller pair having a drive shaft, and a first roller and a second roller coaxially disposed on the shaft, rotatable with the shaft, wherein the second roller is disposed at a position more away from the contact portion than the first roller in the axial direction of the shaft, the second roller having a larger outer diameter than the first roller.

A sheet conveying device includes a sheet loader, a sheet feeder, an optical sensor, and a rotary member. The sheet loader is configured to load a sheet. The sheet feeder is configured to feed the sheet loaded on the sheet loader. The optical sensor is configured to detect the sheet at a predetermined position on the sheet loader in a width direction of the sheet and at a predetermined position in a sheet conveyance passage in the width direction of the sheet. The rotary member is configured to rotate to a first position when the sheet is not at the predetermined position on the sheet loader and a second position when the sheet is at the predetermined position. The rotary member has a detection target portion configured to be detected by the optical sensor when the rotary member is located at the first or second position.

A sheet transport device includes a transport guide for guiding, along its transport surface, a sheet in a transport direction, a first transport roller pair, a second transport roller pair, a skew roller pair, a reference wall, and an actuator. The skew roller pair alone transports, in a skewed manner toward an end of the transport surface in a width direction orthogonal to the transport direction, the sheet spaced from the first transport roller and the second transport roller. The reference wall is positioned at the end of the transport surface in the width direction and extends along the transport direction. The actuator is disposed downstream of the skew roller pair and upstream of the second transport roller pair in the transport direction and between the end and a center of the transport surface in the width direction.

An image forming apparatus includes an engine to form an image on an image forming medium, a paper transfer device to pick up a printing paper and transfer the paper to a transfer path, a sensor to sense a printing paper at a predetermined position on the transfer path, and a processor to determine whether a transfer delay occurs, when the printing paper is sensed, and adjust a pickup timing to advance a pickup of a printing paper of a next page.

To provide an image forming apparatus capable of sufficiently correcting deviation of a recording material by an oscillation operation of a registration roller.

Configuring an image forming apparatus including: a conveyor that conveys a recording material; a transferer that includes a transfer roller that transfers a toner image onto the recording material; a fixer that includes a fixing roller that fixes the toner image formed on the recording material; a deviation detector that detects a position of the recording material in a conveyance intersecting direction; a deviation corrector that is located on an upstream side of the transferer and moves the recording material in the conveyance intersecting direction to correct deviation of the recording material; and a controller that controls a drive amount of the deviation corrector on the basis of a detection result of the deviation detector and the pressure contact force of a nipper nipping the recording material being conveyed.

An imaging system includes: a steering roller located between a first belt roller and a second belt roller, that is inclinable around a fulcrum; and a sensor to detect an amount of displacement of the steering roller due to an inclination of the steering roller. A controller may output a command signal when the amount of displacement of the steering roller exceeds a reference value.

According to some examples, a skew detection device comprises a first roller rotatable around a first axis, a second roller rotatable around a second axis, a first sensor, and a second sensor. The first sensor measures a first rotation parameter from the first roller and the second sensor measures a second rotation parameter from the second roller. A movement of a print media over the device rotates the first contact roller and the second roller, and a controller determines a skew of the print media based on the first and second rotation parameters captured by the first sensor and the second sensor.

An image forming apparatus includes an image forming portion to form an image on an image bearing member, and a transfer portion to transfer the image on a first image position on the image bearing member to a sheet. In addition, a controller determines a second image position, on the image bearing member, of an image to be transferred onto a second surface of a sheet re-conveyed to an adjustment portion by a reverse and re-conveyance portion based on a detected side edge position, of a trailing part of the sheet being conveyed with a first end as the leading edge. The trailing part of the sheet is positioned on a trailing edge side further than a center position, in the sheet conveyance direction, of the sheet, and the controller determines a shift amount based on the second image position and detected side edge position of the sheet, which has been re-conveyed, being conveyed with the second end as the leading edge.