A self-contained no-feed-roll computer controlled corrugated board or paperboard sheet feeder apparatus 200 is configured to upgrade an installed corrugated board processing machine (e.g., 10) and includes a feed table surface 210 for boards (e.g., 2) having drive wheels (222W, 224W, 226W) in an initial variable velocity zone 220 which drives the board in a first motion profile through a first vacuum zone, and a second velocity zone 230 which then drives the board in a second motion profile through a second vacuum zone Retrofittable sheet feeder 200 also includes a controller 300 configured to receive predetermined velocity signals from the host machine 10 and generate (i) a first initial variable velocity control signal for initial variable velocity zone 220 and (ii) a second velocity control signal for second velocity zone 230 in response.

A sheet feeder includes a stacker, a sheet feeding member, an aligner, a switcher, a size specifying unit, and circuitry. The sheet feeding member contacts and feeds a sheet stack on the stacker. The aligner is movable to align a position in a sheet width direction of the sheet stack on the stacker. The switcher switches the aligner from a separation state to a contact state without waiting for a feeding start instruction after the sheet stack is stacked on the stacker. The circuitry delays a switching completion time when the size in the sheet width direction of the sheet stack specified by the size specifying unit is smaller than a given size, to be later than the switching completion time when the size in the sheet width direction of the sheet stack is equal to or greater than the given size.

A sheet feeder includes a stacker, a sheet feeding member, an aligner, a switcher, a size specifying unit, and circuitry. The sheet feeding member contacts and feeds a sheet stack on the stacker. The aligner is movable to align a position in a sheet width direction of the sheet stack on the stacker. The switcher switches the aligner from a separation state to a contact state without waiting for a feeding start instruction after the sheet stack is stacked on the stacker. The circuitry delays a switching completion time when the size in the sheet width direction of the sheet stack specified by the size specifying unit is smaller than a given size, to be later than the switching completion time when the size in the sheet width direction of the sheet stack is equal to or greater than the given size.

A medium transport device includes a feeding roller that feeds a recording medium, a transport roller that transports the recording medium toward a recording head, and a transport motor which is a common driving source for the feeding roller and the transport roller. The medium transport device includes a power transmission mechanism that transmits power of the transport motor to the feeding roller, and a control section that controls a current of the transport motor. The control section measures a current value flowing through the transport motor during driving as a measured current value, and adds a predetermined offset value to the measured current value to set a second limit value as a limit value of the current supplied to the transport motor.

A document feeding device includes a document placement unit at which a document is placed, a feeding roller for feeding the document, and a ranging sensor for measuring a distance to the document located most upward on the document placement unit. A control unit stops feeding the document by the feeding roller based on post-processing distance data obtained by statistically processing time series data of the distance measured by the ranging sensor.

A document feeding device includes a document placement unit at which a document is placed, a feeding roller for feeding the document, and a ranging sensor for measuring a distance to the document located most upward on the document placement unit. A control unit stops feeding the document by the feeding roller based on post-processing distance data obtained by statistically processing time series data of the distance measured by the ranging sensor.

An image forming device comprising: a tray in which multiple number of sheets are stored; a feeder that feeds the sheet stored in the tray; and a hardware processor that: measures a carrying speed of the sheet fed by the feeder; determines whether or not the measured carrying speed is affected by the following sheet; corrects the carrying speed upon determining the carrying speed is affected by the following sheet; and detects a wear status on the feeder based on the measured carrying speed or the corrected carrying speed.

An image forming device comprising: a tray in which multiple number of sheets are stored; a feeder that feeds the sheet stored in the tray; and a hardware processor that: measures a carrying speed of the sheet fed by the feeder; determines whether or not the measured carrying speed is affected by the following sheet; corrects the carrying speed upon determining the carrying speed is affected by the following sheet; and detects a wear status on the feeder based on the measured carrying speed or the corrected carrying speed.

A sheet feeding device includes a sheet loading portion which is capable of an elevating operations, and on which a sheet is loaded, a feeding member for feeding the sheet loaded on the sheet loading portion, the feeding member being capable of elevating movement between a contacting position in contact with the sheet, and a distanced position distanced upward from the sheet, and a control portion that controls the elevating operation of the sheet loading portion and the elevating movement of the feeding member. When the feeding member at the contacting position moves to the distanced position, the feeding member is distanced upward from the sheet loaded on the sheet loading portion after the sheet loading portion starts a descending operation.

A singling apparatus and a system for singling sheet material comprises a sheet store for receiving a sheet stack of sheets to be singled. The sheet store includes a singling gap, which is formed and arranged to deliver a sheet out of the sheet store to a transport mechanism. The singling apparatus comprises further a singling device comprising a rotating separation roller wherein the separation roller comprises partially on its rotational surface a contact area to periodically contact and transport the sheet from the sheet store to the transport mechanism. A position control device of the singling apparatus is coupled to the separation roller and comprises an alignment indication being in correlation with an angle position of the contact area of the separation roller and indicates the alignment of the contact area to the singling gap and/or the sheet.