An assembly method for a planetary roller speed changer is provided. The planetary roller speed changer includes a plurality of planetary rollers that is in rolling contact with both an input shaft and a fixed ring and an output shaft supported by a housing and rotating along with the planetary rollers. An assembly apparatus includes an adjustment apparatus that enables positions of the fixed ring and the housing to be adjusted and a measurement apparatus that measures irregularity of rotation of the output shaft. In an assembly step, the fixed ring and the housing are fixed at a position where the irregularity of rotation of the output shaft is minimized.

A sheet conveying apparatus includes a conveying member conveying and rotating a sheet, a moving member configured to be movable between a first guiding position and a second guiding position, a first abutting portion configured to stop the moving member at the first guiding position, a second abutting portion configured to stop the moving member at the second guiding position, and a planetary gear mechanism. The planetary gear mechanism includes a first rotating element configured to rotate in a first direction and a second direction which is opposite to the first direction, a second rotating element configured to rotate the conveying member by drivenly rotating with the first rotating element, and a third rotating element configured to move the moving member from the second guiding position to the first guiding position by drivenly rotating with the first rotating element rotating in the first direction, and move the moving member from the first guiding position to the second guiding position by drivenly rotating with the first rotating element rotating in the second direction.

A spring-driven reel is adapted to include a gear assembly, and a reel assembly operatively coupled to at least one gear of the gear assembly. The spring-driven reel can also include at least one spring assembly. The spring assembly can include a screw member and a non-rotatable nut moveably mounted to the screw member.

A sheet discharge apparatus includes first and second discharge trays, a support unit, first and second discharge rollers, and first and second controlling units. The second discharge tray is disposed above the first discharge tray and is detachable from the support unit. The first and second discharge rollers discharge a sheet toward the first and second discharge trays respectively. The first controlling unit executes control such that, in a case that the second discharge tray is detached from the support unit while the first discharge roller and the second discharge roller are halted, the first discharge roller remains halted, and in a case that the second discharge tray is detached from the support unit while the first discharge roller and the second discharge roller are rotating, the first discharge roller is halted after the first discharge roller continues rotating until a sheet has been discharged toward the first discharge tray.

A conveyor includes: a first power transmitting mechanism configured to transmit one of forward rotation and reverse rotation of a motor to a first roller and not to transmit the other from a driven member to the first roller; and a second power transmitting mechanism configured to transmit the other rotation to the first roller and not to transmit the one rotation to the first roller. The first power transmitting mechanism includes a transmission delayer that does not transmit rotation of the motor from the driven member to the first roller until the motor is rotated by a particular amount from a time point at which the motor starts to be rotated in a rotational direction of the one rotation when rotation transmitted from the motor to the driven member is changed from the other rotation to the one rotation.

The apparatus includes a first clutch and a second clutch. The first clutch transmits rotation of the driving unit in a first rotation direction to the first feeding device without transmitting rotation of the driving unit in a second rotation direction that is reverse to the first rotation direction to the first feeding device. The second clutch transmits the rotation of the driving unit in the second rotation direction to the conveyance device and the double-side printing conveyance device and without transmitting the rotation of the driving unit in the first rotation direction to the conveyance device and the double-side printing conveyance device. The third transmission path is configured to transmit the rotation of the driving unit to a conveyance device. The fourth transmission path is configured to transmit the rotation of the driving unit to a double-side printing conveyance device.

The apparatus includes a first clutch and a second clutch. The first clutch transmits rotation of the driving unit in a first rotation direction to the first feeding device without transmitting rotation of the driving unit in a second rotation direction that is reverse to the first rotation direction to the first feeding device. The second clutch transmits the rotation of the driving unit in the second rotation direction to the conveyance device and the double-side printing conveyance device and without transmitting the rotation of the driving unit in the first rotation direction to the conveyance device and the double-side printing conveyance device. The third transmission path is configured to transmit the rotation of the driving unit to a conveyance device. The fourth transmission path is configured to transmit the rotation of the driving unit to a double-side printing conveyance device.

A sheet transport device includes a feeding unit that feeds out a sheet from a sheet stack unit, a driving shaft that rotates the feeding unit, plural bearing members that support the driving shaft rotatably at plural positions in an axial direction and restrict movement of the driving shaft in the axial direction, and a fixing member provided integrally with each of the bearing members to removably fix each of the bearing members to an opening and closing member that is opened and closed relative to the sheet stack unit.

A sheet transport device includes a transport unit that transports a sheet to a reading position by a first transport roller, a driving unit that switches a rotating direction, a rotating unit that rotates the first transport roller in one direction, the rotating unit including a one-direction gear that directly meshes with a first planet gear when the driving unit rotates in a first direction and meshes with a second planet gear when the driving unit rotates in a second direction, a switch unit that switches between states in which rotation of the one-direction gear is or is not transmitted to the first transport roller, and a displacement-force applying part that applies a force for displacing the first planet gear to mesh with the one-direction gear when the first planet gear touches the switch unit.

A sheet transport device includes a transport unit that transports a sheet to a reading position by a first transport roller, a driving unit that switches a rotating direction, a rotating unit that rotates the first transport roller in one direction, the rotating unit including a one-direction gear that directly meshes with a first planet gear when the driving unit rotates in a first direction and meshes with a second planet gear when the driving unit rotates in a second direction, a switch unit that switches between states in which rotation of the one-direction gear is or is not transmitted to the first transport roller, and a displacement-force applying part that applies a force for displacing the first planet gear to mesh with the one-direction gear when the first planet gear touches the switch unit.