A paper feeding device 100 includes a support hook 5 that supports a lower edge of a front side of a bundle of stacked paper sheets X, and a paper trailing edge storing part 32 provided between a lower end of the abutting surface 31 and the paper feeding table 11, and the paper feeding device retracts the lowermost layer paper sheet of the loaded paper sheets so as to store its trailing edge in the paper trailing edge storing part 32 and then advance it.

A sheet aligning mechanism includes first and second conveyance mechanisms disposed on first and second sides of a sheet conveyance path, respectively. A nip is formed between the first and second conveyance mechanisms. The first conveyance mechanism includes a first roller, a second roller, and a first conveyance belt wound around the first and second rollers. The first and second rollers are configured to rotate in a first direction along a sheet conveying direction for sheet conveyance, and stop rotation or rotate in a second direction opposite to the first direction for sheet alignment. The first conveyance belt includes an extended region between the first and second rollers in an extending direction inclined with respect to the sheet conveying direction, such that a width of the sheet conveyance path becomes narrower towards the nip in the sheet conveying direction.

A sheet aligning mechanism includes first and second conveyance mechanisms disposed on first and second sides of a sheet conveyance path, respectively. A nip is formed between the first and second conveyance mechanisms. The first conveyance mechanism includes a first roller, a second roller, and a first conveyance belt wound around the first and second rollers. The first and second rollers are configured to rotate in a first direction along a sheet conveying direction for sheet conveyance, and stop rotation or rotate in a second direction opposite to the first direction for sheet alignment. The first conveyance belt includes an extended region between the first and second rollers in an extending direction inclined with respect to the sheet conveying direction, such that a width of the sheet conveyance path becomes narrower towards the nip in the sheet conveying direction.

A sheet processing system according to an embodiment includes a tray that supports a sheet on opposite sides of the sheet orthogonal to a conveyance direction of the sheet. The tray includes a first adjustable support and second adjustable support positioned opposite the first adjustable support in the direction orthogonal to the conveyance direction of the sheet. A skew sensor detects a skew angle of the sheet conveyed to the tray. A corner sensor detects positions of each corner on a front end in the downstream direction of the sheet conveyed to the tray. A controller controls movement of the first and second adjustable supports based on the detected skew angle and the detected positions of each corner on the front end of the sheet conveyed to the tray so that the sheet is conveyed to the tray without jamming.

A sheet feeder including a tray, a feeder roller, a guide, a separator, a motor, a controller, and a sensor, is provided. The sheet feeder separates an object sheet from other sheets in the tray and feed the object sheet through the guide and the separator by rotation of the feeder roller. The controller determines a remaining volume of the sheets in the tray based on a signal from the sensor; generate a velocity profile so that the object sheet is fed at a lower velocity in an earlier first period than a velocity in a later second period; based on the determined remaining volume of the plurality of sheets, modify at least one of a length of the first period and the target velocity in the first period of the velocity profile; and after modification of the velocity profile, control the motor in compliance with the modified velocity profile.

A sheet feeder including a tray, a feeder roller, a guide, a separator, a motor, a controller, and a sensor, is provided. The sheet feeder separates an object sheet from other sheets in the tray and feed the object sheet through the guide and the separator by rotation of the feeder roller. The controller determines a remaining volume of the sheets in the tray based on a signal from the sensor; generate a velocity profile so that the object sheet is fed at a lower velocity in an earlier first period than a velocity in a later second period; based on the determined remaining volume of the plurality of sheets, modify at least one of a length of the first period and the target velocity in the first period of the velocity profile; and after modification of the velocity profile, control the motor in compliance with the modified velocity profile.

A sheet alignment device includes a driven roller, a drive roller, a displacement driving device, an information acquisition portion, and a displacement control portion. The drive roller is configured to rotate in a first rotation direction and in contact with an upper surface of each of sheets conveyed onto a tilt tray, to feed the sheets toward a base end portion of the tilt tray. The drive roller is configured to rotate in a second rotation direction and in contact with an uppermost surface of the sheets, to discharge the sheets from the tilt tray. The displacement control portion is configured to, when the drive roller rotates in the first rotation direction, control a holding position of the drive roller in accordance with the number of the sheets on the tilt tray and thickness information of each of the sheets acquired by the information acquisition portion.

A sheet alignment device includes a driven roller, a drive roller, a displacement driving device, an information acquisition portion, and a displacement control portion. The drive roller is configured to rotate in a first rotation direction and in contact with an upper surface of each of sheets conveyed onto a tilt tray, to feed the sheets toward a base end portion of the tilt tray. The drive roller is configured to rotate in a second rotation direction and in contact with an uppermost surface of the sheets, to discharge the sheets from the tilt tray. The displacement control portion is configured to, when the drive roller rotates in the first rotation direction, control a holding position of the drive roller in accordance with the number of the sheets on the tilt tray and thickness information of each of the sheets acquired by the information acquisition portion.

A sheet aligning mechanism includes first and second conveyance mechanisms disposed on first and second sides of a sheet conveyance path, respectively. A nip is formed between the first and second conveyance mechanisms. The first conveyance mechanism includes a first roller, a second roller, and a first conveyance belt wound around the first and second rollers. The first and second rollers are configured to rotate in a first direction along a sheet conveying direction for sheet conveyance, and stop rotation or rotate in a second direction opposite to the first direction for sheet alignment. The first conveyance belt includes an extended region between the first and second rollers in an extending direction inclined with respect to the sheet conveying direction, such that a width of the sheet conveyance path becomes narrower towards the nip in the sheet conveying direction.

A sheet aligning mechanism includes first and second conveyance mechanisms disposed on first and second sides of a sheet conveyance path, respectively. A nip is formed between the first and second conveyance mechanisms. The first conveyance mechanism includes a first roller, a second roller, and a first conveyance belt wound around the first and second rollers. The first and second rollers are configured to rotate in a first direction along a sheet conveying direction for sheet conveyance, and stop rotation or rotate in a second direction opposite to the first direction for sheet alignment. The first conveyance belt includes an extended region between the first and second rollers in an extending direction inclined with respect to the sheet conveying direction, such that a width of the sheet conveyance path becomes narrower towards the nip in the sheet conveying direction.