Abstract: A sheet stacking apparatus includes a frame, a round member directly or indirectly connected to the frame, and an arm directly or indirectly connected to the frame. The arm is rotatable to rotate between a first position and a second position. The arm is positioned to bias sheets toward the round member when in the first position, and the arm is positioned to bias the sheets away from the round member when in the second position.

Abstract: A media transport system includes a drum with a plurality of rows of holes, a vacuum plenum, and a shutter. The vacuum plenum is positioned within the drum at a position opposite a printhead and the shutter is configured for movement in a cross-process direction. Each row of holes in the drum includes at least one inter-copy gap. The shutter includes a solid member having at least one aperture in it. The shutter is moved to a position so the aperture is aligned with a row of holes and the solid portion of the shutter prevents a flow of air through the vacuum plenum from the holes in other rows of holes not aligned with the aperture in the shutter and the inter-copy gaps in the row of holes aligned with the aperture selectively prevents air flow to the vacuum plenum.

Abstract: A printhead protection apparatus moves between printheads in a printer between a position where cross-members in a frame block media irregularities from striking the faces of the printheads and a position where the cross-members are retracted between adjacent printheads to enable the faces of the printheads to be wiped. The frame of the apparatus encompasses the printheads and the cross-members connected to the frame move between adjacent printheads.

Abstract: A media transport system includes a belt with a plurality of rows of holes, a vacuum plenum, and a shutter. The belt is positioned over the vacuum plenum carries a plurality of media over the vacuum plenum. A row of holes in the belt includes inter-copy gaps that separate media on the belt and the inter-copy gaps include no holes in the belt. The shutter includes a solid member that prevents a flow of air between the vacuum plenum and a portion of the belt positioned above the first shutter and a first aperture formed through the solid member that is aligned with the row of holes in the belt.

Abstract: A vacuum belt moves between a print head and a manifold. The manifold has manifold chambers, and each of the manifold chambers has manifold openings. Vacuum lines are connected to the manifold chambers. The vacuum lines exert vacuum force upon the manifold chambers, and the manifold openings exert the vacuum force through belt perforations. A cylindrical valve structure is connected to the vacuum lines. The cylindrical valve structure includes a cylindrical sleeve (having sleeve openings connected to the vacuum lines) and an internal valve cylinder positioned within the cylindrical sleeve. The internal valve cylinder has groups of vacuum slots. The internal valve cylinder moves linearly within the cylindrical sleeve (in directions parallel to cylindrical walls of the cylindrical sleeve) to align only one of the groups of vacuum slots with the sleeve openings at a time, so as to control which of the manifold chambers receive the vacuum draw.

Abstract: A sheet transport apparatus includes a first belt having a first pattern of first vacuum holes, and a second belt having a second pattern of second vacuum holes. The first belt is positioned on and contacts the second belt. The first belt contacts sheets to be transported. When transporting the sheets on the first belt separated by spaces between the sheets, the first pulleys and second pulleys rotate together and the first belt and the second belt move together. When not transporting the sheets, a controller controls pulleys to move the first belt relative to the second belt so as to leave blocked-hole regions of the first belt where the spaces between the sheets are located. The blocked-hole regions are locations of the first belt where the first vacuum holes are unaligned with the second vacuum holes and the first vacuum holes are blocked by the second belt.

Abstract: A media transport system provides full vacuum under media as the media traverses an entire print path of an ink jet printer while simultaneously providing for a no-vacuum inter-copy gap that moves along with the media past print heads of the ink jet printer. This is accomplished with a dual vacuum inner/outer vacuum drum system that includes a first drum that has a matrix of holes that allows for full coverage of vacuum with a second underlying drum that is shifted to align a second set of holes to match the sheet pitch. By shifting the second drum in relation to the first drum, a combination set of holes is aligned to provide full vacuum across the media while a column of holes is blocked to provide a non-vacuum inter-copy gap.

Abstract: A printer attenuates banding visual defects arising from a lack of flatness in media as ink is ejected onto the media. The printer includes a detector that generates a signal corresponding to the slope in the media and a controller that modulates a volume of the ink drops ejected by one or more printheads in the vicinity of the slope in the media.

Abstract: A system and method are provided for implementing an automated process that independently manipulates a plurality of span-wise discrete individual pressure actuators in a movable pressure assembly associated with a nip-based drive unit to drive tensioned web continuous feed image receiving media in web-based printing devices. The disclosed process varyingly adjusts a relative pressure of between the opposing rolls to address a detected wrinkling condition. A closed loop detection and control scheme is provided in which, based on a determination that wrinkling is occurring in tensioned web continuous feed image receiving media, and isolation of a spanwise location in which the wrinkling is occurring, differential signals may be sent to one or more of a plurality of span-wise discrete individual pressure actuators in a movable pressure assembly to varyingly adjust a relative pressure of the two opposing rolls across a spanwise pressure nip.

Abstract: A scissor lift apparatus includes a sliding carriage member and a pivoting linkage added to a conventional scissor lift in order to lower the force required to lift a tray holding heavy media during the initial portion of the lifting action where the scissor lift is fully compressed.

Abstract: A method for printing includes the use of a protective guide system that protects a print head nozzle plate from physical contact with objects such as a curled print medium. The print head nozzle plate includes a nozzle array including a plurality of nozzles arranged in a plurality of subarrays. The plurality of subarrays are spaced from each other by a plurality of intranozzle areas devoid of nozzles. The protective guide system includes a frame and a plurality of cross members aligned with the intranozzle areas between the subarrays. The protective guide system thus protects the print head nozzle plate without obstructing the ink during printing.

Abstract: A scissor lift apparatus includes a sliding carriage member and a pivoting linkage added to a conventional scissor lift in order to lower the force required to lift a tray holding heavy media during the initial portion of the lifting action where the scissor lift is fully compressed.

Abstract: A printer attenuates banding visual defects arising from a lack of flatness in media as ink is ejected onto the media. The printer includes a detector that generates a signal corresponding to the slope in the media and a controller that modulates a volume of the ink drops ejected by one or more printheads in the vicinity of the slope in the media.

Abstract: A method for printing includes the use of a protective guide system that protects a print head nozzle plate from physical contact with objects such as a curled print medium. The print head nozzle plate includes a nozzle array including a plurality of nozzles arranged in a plurality of subarrays. The plurality of subarrays are spaced from each other by a plurality of intranozzle areas devoid of nozzles. The protective guide system includes a frame and a plurality of cross members aligned with the intranozzle areas between the subarrays. The protective guide system thus protects the print head nozzle plate without obstructing the ink during printing.

Abstract: A print head protection device is used with an inkjet printer having a print head adapted for elevating. A roller is mounted upstream of the print heads and above the process path a predetermined distance. A cover on the roller outer surface contacts the sheet lead edge if sheet curl exceeds a set curl range. The cover will cause rotation of the roller by engaging the sheet. A rotary encoder is mounted for synchronous rotation with the roller. The rotary encoder generates a signal in response to rotation of the roller, raising the print head to preclude damage. Alternately, the sheet can be discarded.

Abstract: A protective guide system that protects a print head nozzle plate from physical contact with objects such as a curled print medium. The nozzle plate includes a nozzle array including a plurality of nozzles arranged in a plurality of subarrays. The plurality of subarrays are spaced from each other by a plurality of intranozzle areas devoid of nozzles. The protective guide system includes a frame and a plurality of cross members aligned with the intranozzle areas between the subarrays. The protective guide system thus protects the nozzle plate without obstructing the ink during printing.

Abstract: A paddle wheel compiler includes a paddle wheel that accepts sheets from the front of the paddle wheel to form a set, unlike a disk stacker which accepts sheets from the top or back of the disk and flips the sheet. The paddle wheel compiler is unique in that it maintains control of all sheets in a set, except for the top sheet during tamping. The top sheet is registered to the set with side tampers, followed by a scuffing action to register the sheet against a registration wall in the process direction.

Abstract: A printer attenuates curl in media sheets being printing by the printer. The printer includes a moisture ejecting subsystem that ejects a water-containing material in the margins of the media sheet in the cross-process direction to reduce a moisture gradient across the media sheet when the grain of the media is parallel to the process direction of the media moving through the printer.

Abstract: A paddle wheel compiler includes a paddle wheel that accepts sheets from the front of the paddle wheel to form a set, unlike a disk stacker which accepts sheets from the top or back of the disk and flips the sheet. The paddle wheel compiler is unique in that it maintains control of all sheets in a set, except for the top sheet during tamping. The top sheet is registered to the set with side tampers, followed by a scuffing action to register the sheet against a registration wall in the process direction.

Abstract: A method and system for controlling a crown height associated with a nip profile includes adjusting pressure of a pressure roll. This may influence the shape of the pressure roll which may influence the nip profile. This may help prevent wrinkling and extend the life of the pressure roll. The pressure roll may be configured to have a varying wall thickness across a width of the pressure roll. The pressure roll may be used for a web application.