A sheet processing apparatus comprises a roller disposed in a sheet conveyance path; a sheet sensor disposed in the sheet conveyance path and configured to detect conveyance of sheets and generate sensor information indicative of detection; and a controller. The controller is configured to, for each sheet of a predetermined number of sheets of a plurality of sheets conveyed by the roller, use the sensor information to generate an individual sheet-conveyance dataset indicating a sheet passage interval; and store the individual sheet-conveyance dataset in data storage. The controller is further configured to, after the roller conveys the predetermined number of sheets, calculate a summary sheet-conveyance dataset including sheet passage interval statistics for the predetermined number of sheets; store the summary sheet-conveyance dataset in the data storage; discard the individual sheet-conveyance datasets from the data storage; and evaluate the sheet passage interval statistics to determine whether to modify the predetermined number of sheets.

A sheet processing apparatus comprises a roller disposed in a sheet conveyance path; a sheet sensor disposed in the sheet conveyance path and configured to detect conveyance of sheets and generate sensor information indicative of detection; and a controller. The controller is configured to, for each sheet of a predetermined number of sheets of a plurality of sheets conveyed by the roller, use the sensor information to generate an individual sheet-conveyance dataset indicating a sheet passage interval; and store the individual sheet-conveyance dataset in data storage. The controller is further configured to, after the roller conveys the predetermined number of sheets, calculate a summary sheet-conveyance dataset including sheet passage interval statistics for the predetermined number of sheets; store the summary sheet-conveyance dataset in the data storage; discard the individual sheet-conveyance datasets from the data storage; and evaluate the sheet passage interval statistics to determine whether to modify the predetermined number of sheets.

A sheet conveyance apparatus includes a first conveyor, a second conveyor provided downstream of the first conveyor, a first motor configured to drive the first conveyor, a second motor configured to drive the second conveyor, a speed determining unit configured to determine a rotation speed of a rotor of the second motor, a command determining unit configured to determine a command speed representing a target speed of the rotor of the second motor, and a controller configured to control a drive current flowing through a winding of the second motor so that a deviation between the command speed determined by the command determining unit and the rotation speed determined by the speed determining unit is decreased. The command determining unit determines the command speed based on a value corresponding to a rotation speed of a rotor of the first motor.

A sheet conveyance apparatus includes a first conveyor, a second conveyor provided downstream of the first conveyor, a first motor configured to drive the first conveyor, a second motor configured to drive the second conveyor, a speed determining unit configured to determine a rotation speed of a rotor of the second motor, a command determining unit configured to determine a command speed representing a target speed of the rotor of the second motor, and a controller configured to control a drive current flowing through a winding of the second motor so that a deviation between the command speed determined by the command determining unit and the rotation speed determined by the speed determining unit is decreased. The command determining unit determines the command speed based on a value corresponding to a rotation speed of a rotor of the first motor.

A medium feeding mechanism includes a feeder that feeds a medium, a transportation path that is coupled to the feeder and includes a bent portion, a transporter that transports the medium on the transportation path, and a transportation control unit that controls the transporter, wherein the transportation control unit adjusts a transportation velocity of the medium transported by the transporter on the basis of medium information of the medium and a transportation route shape for the medium.

A medium feeding mechanism includes a feeder that feeds a medium, a transportation path that is coupled to the feeder and includes a bent portion, a transporter that transports the medium on the transportation path, and a transportation control unit that controls the transporter, wherein the transportation control unit adjusts a transportation velocity of the medium transported by the transporter on the basis of medium information of the medium and a transportation route shape for the medium.

A medium conveying apparatus includes a storage device, a feed roller to feed a medium, and a processor to determine whether a conveyance abnormality of the medium fed by the feed roller has occurred, store in the storage device that the conveyance abnormality has occurred and stop feeding of the medium when the processor determines that the conveyance abnormality has occurred, and notify a user of a cleaning instruction or a replacement instruction of the feed roller based on an occurrence degree of the conveyance abnormality for a plurality of media fed by the feed roller.

A medium conveying apparatus includes a storage device, a feed roller to feed a medium, and a processor to determine whether a conveyance abnormality of the medium fed by the feed roller has occurred, store in the storage device that the conveyance abnormality has occurred and stop feeding of the medium when the processor determines that the conveyance abnormality has occurred, and notify a user of a cleaning instruction or a replacement instruction of the feed roller based on an occurrence degree of the conveyance abnormality for a plurality of media fed by the feed roller.

The rotation of a lifting and lowering plate 56 is controlled such that, in a case where the height of the sheet loaded in a manual feed tray 50 is maximum, a feed roller 51 abuts the sheet at a first abutment position at a first moving velocity slower than a second moving velocity at a position upstream in the movement direction of the feed roller 51 from the first abutment position, and, in a case where the height of the sheet loaded in the manual feed tray 50 is minimum, the feed roller 51 abuts the sheet at a second abutment position at a third moving velocity slower than the first moving velocity at the first abutment position.

The rotation of a lifting and lowering plate 56 is controlled such that, in a case where the height of the sheet loaded in a manual feed tray 50 is maximum, a feed roller 51 abuts the sheet at a first abutment position at a first moving velocity slower than a second moving velocity at a position upstream in the movement direction of the feed roller 51 from the first abutment position, and, in a case where the height of the sheet loaded in the manual feed tray 50 is minimum, the feed roller 51 abuts the sheet at a second abutment position at a third moving velocity slower than the first moving velocity at the first abutment position.