There is provided a sheet feeding apparatus for feeding a sheet. The sheet feeding apparatus includes: a feeding roller that feeds a sheet; and a moving mechanism that moves the feeding roller to a feeding position where the feeding roller contacts the sheet, to a first retracting position where the feeding roller is separated from the sheet, and to a second retracting position lying between the feeding position and the first retracting position.

An image recording apparatus includes a conveyance mechanism conveying a sheet-shaped medium in a conveyance direction, a recorder recording an image on the conveyed sheet-shaped medium, and a controller. The conveyance mechanism selectively conveys a first sheet-shaped medium accommodated in a first accommodation part, and a second sheet-shaped medium accommodated in a second accommodation part and longer than the first sheet-shaped medium in the conveyance direction. The controller causes, based on a recording command, the conveyance mechanism to convey a sheet-shaped medium from one of the first and second accommodation parts, and causes the recorder to record an image on the sheet-shaped medium. In a case where accommodation part information in the recording command indicates the first accommodation part, and medium information in the recording command indicates the second sheet-shaped medium, the controller causes the conveyance mechanism to convey the second sheet-shaped medium from the second accommodation part.

A sheet conveyance apparatus includes a conveyance section, the conveyance section including a roller rotatable in a first rotation direction and a second rotation direction, a guide member configured to move between a first position and a second position, a drive source, a drive switching unit including an input unit, an output unit, and a switching unit, a drive interruption unit configured to transition between a transmission state and a non-transmission state. The roller is configured to rotate by the driving force output from the output unit of the drive switching unit while the guide member moves between the first position and the second position.

A document feeder constituting an image forming apparatus includes a paper feeder to supply a document to a document transport path, a first transporter to transport the document toward image reading positions, and a second transporter to transport the document toward the document discharging tray while supplying the document to the image reading positions. Furthermore, the document feeder includes a motor provided on the first frame, a first driver provided on the first frame and to transmit driving force generated by the motor to the paper feeder and the first transporter, a second driver provided on the second frame and to transmit the driving force generated by the motor to the second transporter, and a second driver to transmit the driving force generated by the motor to the second transporter, and a relay transmission member to transmit the driving force generated by the motor to the second driver.

A sheet conveyance device includes a rotary shaft, a conveyance roller, a driving source, and a gear. The gear rotates integrally with the rotary shaft and transmits a driving force from the driving source to the conveyance roller. The gear includes a tooth portion engaging with another gear, a wall surface forming a hole into which the rotary shaft is inserted, a deformable portion, and a pressing part. The deformable portion has a cantilever shape at least partially provided in an area provided with the tooth portion in a gear rotation axis direction. The pressing part protrudes from the wall surface toward the rotation center of the gear, and is elastically deformed by being pressed by the rotary shaft. The pressing part presses the rotary shaft toward the wall surface on a side opposite to the deformable portion in a state where the gear is attached to the rotary shaft.

A medium conveyor apparatus includes a main body, a first roller that is rotatably supported by the main body, and that receives a rotating force from a driving source, a bearing that is translationally movably supported by the main body, a second roller that is rotatably supported by the bearing, and that presses a medium against the first roller, and a rotation communicator that communicates a rotation from the driving source to the second roller, without communicating a rotation from the second roller to the driving source.

A medium conveying apparatus includes a first roller, a second roller located to face the first roller, to hold and convey a medium with the first roller, a drive shaft to rotate the second roller, a motor to rotate the drive shaft, and a joint to connect the second roller and the drive shaft. The joint is configured to keep connecting the second roller and the drive shaft when the second roller moves in a vertical direction. The drive shaft is located at an intermediate position between a first position where the second roller is in contact with the first roller and a second position where the second roller separates most from the first roller in the vertical direction. A distance between the second position and the intermediate position is greater than a radius on cross section of the second roller in the vertical direction.

A printing apparatus includes a conveyance unit to convey a print medium, a belt, a tensioner, and a control unit. The belt transmits a driving force of a drive unit to the conveyance unit. The tensioner is displaceable and makes pressure contact with the belt to generate tension. The control unit controls driving of the drive unit in a state where the tensioner is in pressure contact with the belt. The control unit performs first control in which the drive unit is driven with a first control value, which is not based on a driving amount detected by a detection unit. Where the detection unit detects the driving amount, the control unit subsequently performs second control in which the drive unit is driven with a second control value, which is based on the driving amount detected by the detection unit.

A drive mechanism that drives a rotator to rotate includes a main motor, an assist motor, and processing circuitry. The main motor drives the rotator. The assist motor drives the rotator and assists a drive of the rotator by the main motor. The processing circuitry controls a speed of the main motor so that a rotational speed of the rotator is constant, and controls a motor voltage of the assist motor so that the motor voltage of the assist motor changes according to a change in a motor current of the main motor.

There is provided a sheet feeding apparatus for feeding a sheet. The sheet feeding apparatus includes: a feeding roller that feeds a sheet; and a moving mechanism that moves the feeding roller to a feeding position where the feeding roller contacts the sheet, to a first retracting position where the feeding roller is separated from the sheet, and to a second retracting position lying between the feeding position and the first retracting position.