A first transport path is put into a first state capable of transporting a paper sheet when a first portion and a second portion engage with each other, and put into a second state in which the second portion is swingable with respect to the first portion about a first swing axis extending in a direction orthogonal to a first direction and horizontal when engagement between the first portion and the second portion is released. A contact portion comes into contact with the second portion, thereby engaging the second portion with the first portion when a second unit in which the first transport path is in the second state is moved in a second direction opposite to the first direction.

A medium supply device is provided that includes a single sheet paper accommodating unit at which media are stacked and placed, and a feeding roller configured to feed the media by rotating in contact with a top surface of the placed media. The feeding roller includes a contact portion configured to contact the single sheet paper and a non-contact portion configured to not contact the single sheet paper in a rotational direction, and a plurality of the contact portions and the non-contact portions are provided in a first direction that is an extending direction of a rotation axis of the feeding roller, and the contact portions adjacent to each other in the first direction are out of phase in the rotational direction.

A sheet feeding device includes a tray, a feeding member, a conveying member, a separation member, a transmission unit, and a biasing member. The separation member abuts the conveying member and separates a single sheet from sheets fed by the feeding member. The transmission unit includes first and second portions respectively having first and second transmission surfaces. Where the first and second transmission surfaces abut each other, the first portion drives the second portion that drives the feeding member. The biasing member biases either of the first and second portions so that the first and second transmission surfaces move away from each other. The conveying member is driven in a state where the separation member abuts the conveying member and the feeding member abuts the sheet stacked on the tray and is stopped. Thereafter, the first and second transmission surfaces abut each other, and the feeding member is driven.

A sheet feeding apparatus includes a sheet supporting portion, a feeding portion, a conveying portion configured to convey the sheet fed by the feeding portion, a separation member, a returning portion, the returning portion pushing the sheet back toward the sheet supporting portion by moving from a retracting position to a protruding position, and a pressing portion including a contact portion configured to contact the sheet. The pressing portion is configured to press the sheet from above via the contact portion such that the sheet is pushed toward the returning portion in a state where the returning portion is positioned at the protruding position and below the sheet.

A sheet conveyer having a sheet tray, a tray-driving mechanism, a conveyance guide, a feed roller, a separator, a conveyer, a conveyer-driving mechanism, a controller, and a sheet sensor to detect sheets on the sheet tray, is provided. The conveyer-driving mechanism includes a transmission-active portion and a transmission-passive portion. A conveying velocity to convey the sheets by the conveyer is higher than a conveying velocity to convey the sheets by the feed roller and the separator. The transmission-active portion and the transmission-passive portion are rotatable about a transmission axis. The transmission-passive portion rotates passively by being pushed by the transmission-active portion. After the sheet sensor detects absence of the sheets, and before the transmission-passive portion starts rotating passively, the controller conducts a specific action to move the sheet tray downward by controlling the tray-driving mechanism.

Provided is a document conveying apparatus that properly discharges documents regardless of the amount of documents stacked on a discharge tray without complicated construction of a transmission mechanism for transmitting a driving force to conveying rollers. A conveying roller pair is provided at an end portion on an upstream side. A swing mechanism swings a discharge mechanism centered around a drive shaft of the conveying roller pair. An upper surface height measuring unit measures the height of the upper surface of documents stacked on the discharge tray. A control unit, by causing the swing mechanism to swing the discharge mechanism according to the height measured by the upper surface height measuring unit, performs control so that the difference between a discharge port and the upper surface of the documents stacked on the discharge tray is within a specified range.

According to one embodiment, a sheet conveying device includes a roller, a motor, a clutch, and a torque generator. The roller conveys a sheet. The motor is a driving source. The clutch connects or disconnects drive of the motor with respect to the roller. The torque generator applies a torque to the roller.

A sheet alignment apparatus includes a supporting portion configured to support a sheet, a first alignment member configured to abut an end portion in a first direction of the sheet supported by the supporting portion and align a position of the sheet in the first direction, a first moving unit configured to move the first alignment member in the first direction, a second alignment member configured to abut an end portion in a second direction of the sheet supported by the supporting portion and align a position of the sheet in the second direction, the second direction being perpendicular to the first direction, and a second moving unit configured to move the second alignment member in the second direction, wherein the first moving unit is disposed below the supporting portion, and wherein the second moving unit is disposed above the supporting portion.

A sheet processing apparatus for processing sheets includes: a stack tray on which a sheet is stacked; a discharge roller pair composed of first and second rollers and configured to discharge a sheet onto the stack tray, the second roller being configured to be movable between a pressure contact position to contact with the first roller and a retracting position to separate from the first roller; and a pressure contact/separation mechanism for moving the second roller from the retracting position to the pressure contact position. The pressure contact/separation mechanism changes the timing at which the second roller reaches the pressure contact position according to the type of a sheet to be discharged.

A medium discharging device includes a first tray, a second tray receiving a medium from the first tray, a supporter which is configured to be displaced from a retreat position in the first tray and an advance position above the second tray and which supports the medium, an aligner which is provided in the supporter and that aligns a first end portion which is an upstream end portion in a discharge direction of the medium supported by the supporter, to be displaced together with the supporter, and a restrictor configured to be displaced between a restriction position where an upstream movement of the first end portion of the medium in a position of the aligner in the discharge direction and a non-restriction position where the movement is not restricted, when the supporter is in the advance position.