A correction structure arranged in a feeding path of a document processing device, comprising: a transmitting means consisted of at least a pair of roller sets which are arranged symmetrically on the two sides of the feeding path for transmitting the card evenly, a correcting means consisted of a platform movably arranged at the downstream to the roller set, a receptacle formed on the platform, an elastic object arranged in the receptacle for returning the platform to a predefined location, a back wall extended from the platform toward the feeding path, an opening formed on the back wall to let a card go through, and a friction pad arranged at the bottom of the opening to partly jam the opening, wherein the width of the friction pad is less than the width of the feeding path so the friction pad only contacts the center of the card while transmitting the card.

Example implementations relate to print media stacks. In some examples, a device may include a sheet channel to guide a sheet of print media within the sheet channel above and separated in a vertical direction from a stack of printed media when the sheet of print media exits a print path of a printer. The device may include a plurality of clamps to control alignment of the sheet of print media on the stack of printed media when the sheet channel moves outboard from the sheet of print media to allow the sheet of print media to fall onto the stack of printed media, wherein the plurality of clamps sequentially pin the sheet of print media to the stack of printed media from a middle portion of the sheet of print media outward.

Example printer finishing apparatus are described herein. An example printer disclosed herein includes an alignment guide, a track to align a sheet relative to the alignment guide, a clamp to move between a raised position and a lowered position relative to the sheet, and a force applicator coupled to the clamp. The force applicator is to cause the sheet to engage the alignment guide when the clamp is in the lowered position.

Example printer finishing apparatus are described herein. An example printer disclosed herein includes an alignment guide, a track to align a sheet relative to the alignment guide, a clamp to move between a raised position and a lowered position relative to the sheet, and a force applicator coupled to the clamp. The force applicator is to cause the sheet to engage the alignment guide when the clamp is in the lowered position.

A sheet stacker includes a pair of sheet holders, a sheet leading-edge aligner, a sheet stacking member, and control circuitry. A downstream side of the pair of sheet holders in a conveyance direction of a conveyed sheet is lowered along the conveyance direction. Each one of the pair of sheet holders is movable in an orthogonal direction to the conveyance direction. The pair of sheet holders hold both side-end portions of the sheet in the orthogonal direction. The sheet stacking member is disposed below the pair of sheet holders. A downstream side of the sheet stacking member in the conveyance direction is lowered along the conveyance direction. The sheet stacking member stacks the sheet dropped from the pair of sheet holders after a leading edge of the sheet is aligned by the leading-edge aligner. The control circuitry controls operations of the leading-edge aligner and the pair of sheet holders.

A printing device is provided comprising a camera to capture an image of at least a portion of a print substrate; a controller to determine a location of a portion of a side edge of the substrate from the image to determine a distance of the print substrate from a predetermined location; and adjustment apparatus to adjust the entire substrate laterally, relative to the direction of transport of the substrate, based on the determined location.

A device for laterally guiding (1) a metal strip (2) running over a metal strip conveyor device. The device has at least one main part module (3) with a guiding plane (4) and at least one grinding body with a grinding surface (5a, 5b, 5c) for contacting the metal strip (2) to be guided for guiding purposes. The grinding body (6) is attached to a support element (7), or the grinding body (6) includes the support element (7). The support element (7) is mounted in the main part module (3) in a movable manner in the direction of the rotational axis (10) and in a rotatable manner. The position of the grinding body in relation to the guiding plane (4) is modified by moving the support element (7) prior to or while laterally guiding metal strips running over a metal strip conveyor device, prior to contacting a first metal strip for guiding purposes, and/or while contacting a first metal strip for guiding purposes.

Example implementations relate to print media stacks. In some examples, a device may include a sheet channel to guide a sheet of print media within the sheet channel above and separated in a vertical direction from a stack of printed media when the sheet of print media exits a print path of a printer. The device may include a plurality of clamps to control alignment of the sheet of print media on the stack of printed media when the sheet channel moves outboard from the sheet of print media to allow the sheet of print media to fall onto the stack of printed media, wherein the plurality of clamps sequentially pin the sheet of print media to the stack of printed media from a middle portion of the sheet of print media outward.

Unwinder of a thin ply product wound on a roll, comprising a first roll-holder assembly equipped with a first unwinding rod for a respective roll, on which the roll is adapted to be supported, and which has an axis of rotation transversal to the direction of movement of the ply unwound from the roll, a second roll-holder assembly equipped with a second unwinding rod of a respective roll, on which the roll is adapted to be supported, said second rod being parallel to said first unwinding rod of the first roll-holder assembly, said second roll-holder assembly facing said first roll-holder assembly in an unwinding zone, a ply splicing assembly placed above said first and second facing roll-holder assemblies, a ply accumulation unit to allow automatic switching between a roll being unwound in one said roll-holder assembly and a spare roll provided in the other roll-holder assembly, a system for the lateral movement of each of said unwinding rods with respect to said unwinding zone, from said unwinding zone to a loading zone wherein said rolls are outside said winding zone to facilitate loading the rolls into the respective roll-holder assemblies, wherein said splicing assembly can be moved from a working position above the two said roll-holder assemblies in said unwinding zone, to a working position above an extracted roll assembly in the loading zone, to allow preparation for splicing of the leading edge of the ply wound on the spare roll.

An apparatus and method for determining sheet material edges on a surface including a sensor configured to detect an outer edge and a usable edge of the sheet material and a controller in communication with the sensor. The sensor comprises a first color optical sensor producing a first signal representing a first physical attribute of the sheet material and a second color optical sensor producing a second signal representing a second physical attribute of the sheet material. The controller comprises a processor, a memory, and a communications adapter, controls dispensing and spreading of the sheet material for detection by the sensor, and signals to a user a presence of the usable edge in the sheet material upon detection by the sensor.