Abstract: A media handling system having an endless belt which carries a media sheet through a print zone achieves improved media advance accuracy by including closed loop feedback control. The position of either a drive shaft which rotates the endless belt or the endless belt itself is monitored to provide feedback to a drive motor. The drive motor is linked to the drive shaft through a gear train. The endless belt is rotated by the drive shaft, either directly, or through rollers mounted to the drive shaft.

Abstract: A platen surface structure construct, particularly useful in a hard copy apparatus for a vacuum holddown, is configured by dimensioning print media platen surface structure channels and ports in order to ensure print media leading edge and trailing edge holddown. Moreover, the vacuum is distributed across the platen surface in accordance with predetermined dye flow characteristics based upon known dye composition and known print medium composition and such that print artifacts are not created by vacuum pulling wet dye through the capillaries of the medium.

Abstract: To maintain a uniform spacing between the print media, such as paper or fabric, and an inkjet printhead having a large print swath, for instance about 25 millimeters (one inch) wide, a new media support system is provided for inkjet printing mechanisms, such as printers or plotters. The support system employs an endless belt (62) driven from the belt interior surface by a roller drive system that uniformly supports the printhead media under the reciprocating printhead (54, 56). The belt may be lined with anti-cockle ribs or it may be foraminous, with a vacuum applied thereunder to pull the media onto the belt. An ink drying system is included for heating the belt and thus the media to avoid ink bleed. A method is also provided for supporting and transporting a large sheet of print media through a printzone of an inkjet printing mechanism having such a large swath inkjet head.

Abstract: Inkjet pens are combined in a printer so that the swaths printed by individual pens are combined into a resultant, wide swath that increases printer throughput. The print medium is carried on a drum and advanced through the printer. In a preferred embodiment, sets of two pens, each set having the same color of ink, are carried near the drum with the two pens arranged such that the swath of one pen is adjacent to the swath of the other pen in a direction that is parallel to the drum axis. Also provided is a carriage assembly for carrying the pens in the just mentioned arrangement for combining the swath widths of the individual pens. The components of the carriage assembly are such that two pens of the same color ink are precisely positioned relative to each other, thereby to meet a very close tolerance requirement for arranging two pens of the same color.

Abstract: Accurate advance of a media sheet is achieved by carrying the media sheet on a belt loop support. An upstream pinch roller holds the media sheet to the belt upstream of the print zone. A downstream pinch roller holds the media sheet to the belt downstream of the print zone. A guide shim extends along the media path from a position upstream of the upstream pinch roller, passed the upstream pinch roller under a printhead adjacent to the print zone. The location of a lead edge of the guide shim relative to the print zone determines the minimum bottom margin for the inkjet printing device. The guide shim presses the media sheet to the belt support and keeps the media sheet flat under the inkjet printhead as the printhead moves over the media sheet.

Abstract: A difference in feed roller diameter from one printer to another causes a media to advance by a different amount for a given rotation of a drive shaft to which the feed roller is coupled. Such variation in advance distance is a linefeed error. Mean linefeed error is determined and corrected by printing a test plot having several areas. Each area is formed of the same image pattern, but is printed at a different linefeed error adjustment to compensate for mean linefeed error. The different adjustments are prescribed and span a typical compensation range for a given print engine model. The different adjustment factors cause banding to occur in some areas. The user picks one of the test pattern areas which has the highest print quality (i.e., least or no banding). The linefeed adjustment factor corresponding to such area is used for normal printing.

Abstract: A media feed apparatus for a printer, with a motorized media pick mechanism and a media support plate movable toward and away from the pick element, so that a stack of media on the plate may be brought into contact with the pick mechanism. A lifter assembly is continuously movable between a first position and a second position, and has a cam surface supportably contacting the media support plate. A first cam surface portion contacts the support plate when the lifter assembly is in the first position, and a second cam surface portion contacts the support plate when the lifter assembly is in the second position. The support plate may have a protrusion over which the cam surface slides, and the cam may pivoted to provide a selectable lever arm, depending on the point of contact.

Abstract: A shifted element printing/scanning routine coordinated with media advance through an interaction zone of hardcopy device is provided for inkjet printing mechanisms, scanners or multi-function hardcopy devices. A method is provided of coordinating operation of a reciprocating head with media advance. The head has plural interaction elements, which may be ink-ejecting nozzles in a printing mechanism, or image receptors in a scanning mechanism, with the interaction elements being arranged in a linear array to selectively interact with media. A hardcopy device has a rotating media advancing member, a reciprocating head carrying the interaction elements, an encoder having indicia to track media advance, and a sensor that interprets the encoder indicia and generated a media position signal.

Abstract: To maintain a uniform spacing between the print media, such as paper, and an inkjet printhead having a large print swath, for instance about 25 millimeters (one inch) wide, a new media support system is provided for inkjet printing mechanisms, such as printers or plotters. The support system employs an endless belt driven from the belt interior surface by a roller drive system that uniformly supports the print media under the reciprocating printhead. The belt may be lined with anti-cockle ribs to support the media when saturated. The belt may also be foraminous, with a vacuum applied thereunder to pull the media onto the belt. A method is also provided for supporting and transporting a large sheet of print media through a printzone of an inkjet printing mechanism, such as an inkjet plotter, that uses such a large swath inkjet printhead.

Abstract: A sheet media handling system is provided for use in a sheet processor (e.g., a printer). Such system incorporates an input tray for storing one or more sheet media prior to input through the printer's input port with the input tray vertically stacked with the printer's output support structure or tray. The system also has a single sheet medium guide mechanism adjacent the printer's output support structure, where the medium guide mechanism routes a single medium to the input port when the single medium is inserted therein. The single sheet medium guide mechanism includes a skew-abatement substructure and a deflection mechanism. The skew-abatement substructure is designed to facilitate alignment of and routing of a single medium towards the input port by contacting a first edge of the single medium and an opposite second edge of the single medium.

Abstract: Described herein is a printer having a printhead which traverses laterally across a sheetlike print medium and which thereby defines a laterally-extending print zone across the print medium. A paper transport mechanism in the printer has drive rollers and associated pinch wheels to drive the print medium through the printer's print zone. The paper transport mechanism further includes an upper print media guide and a lower print medium guide. The two print medium guides are shaped at their transverse ends to bow the transverse edges of the print medium downwardly to reduce its tendency to buckle upwardly into the printhead. In order to fit the upper print medium guide into the limited available space above the drive rollers, it is made of a lower molded portion for paper contact and an upper backing portion for rigidity. A pinch finger extends toward the printer's print zone beyond the pinch wheels to establish a pinch point against the drive roller in near proximity to the print zone.

Abstract: Described herein is a print medium support mechanism for supporting a print medium such as paper in a print zone adjacent a printer's printhead. The print medium support mechanism includes at least one drive roller positioned upstream from the print zone of the printer to feed paper into the print zone. An upper print media guide is positioned adjacent the drive roller between the drive roller and the print zone to contact and support the paper from above. A lower print media guide is mounted downstream from the upper print media guide to pivot between retracted and non-retracted positions relative to the print zone. When in its non-retracted position, the lower print media guide contacts and supports the paper from below. The support of the upper and lower print media guides against opposite sides of the paper is primarily responsible for establishing the shape and angle of the paper as it passes through the print zone.

Abstract: A sheet stacking system is provided which includes mechanism designed to compensate for the aerodynamic forces which act on a sheet as it passes from the printer's output port to the floor of the printer's output tray. The system includes a pair of spaced, anti-sail wings which are positioned adjacent the printer's output port so as to controlledly receive just-expelled sheets. The wings are operatively associated with the output tray's floor, and are arranged so that opposite movement thereof results in rear-to-front sequential release of a supported sheet, directing substantially vertical passage of such sheet to the top of an output stack.

Abstract: An improved printer paper stack-handling device is described. In its preferred embodiment, the stack-handling device includes a pivot member with a downwardly inclining paper top-of-stack contact surface. The device also includes a force mechanism, e.g. a leaf spring, to pivot the member into contact with the top sheet of a paper stack. The spring and the pivot member's inclined contact surface produce a variable top sheet bias for corresponding variable paper stack heights, to properly laterally align the top sheet against a fixed, opposing guide rail, for feeding to a printer input port.

Abstract: An improved printer paper pullout apparatus is described. In its preferred embodiment, the pullout apparatus includes a grasping mechanism, a capture mechanism and a securing mechanism. The grasping mechanism facilitates concurrent paper tray and paper stack movement from a printer feed zone. The securing mechanism ensures proper paper gripping before the paper tray can be released and extended from the printer feed zone. In addition, the grasping mechanism is shaped and positioned on the paper tray for ease of operator grip when manually extending the paper tray from the printer feed zone.

Abstract: A separator is provided for use in a sheet pick-up system, the separator including a rigid body having a base portion and a wear-resistant upstanding portion. The separator is mounted adjacent the printer's input port and is biased toward a motor-driven roller, pinching input sheets between the roller and the separator's upstanding portion so that the roller may pull the top sheet across the second sheet and the upstanding portion. A frictionally adherent pad is formed in operative association with the body so as to extend in a region forward of the upstanding portion and contact the second sheet to oppose intake thereof.

Abstract: A paper handling system is provided which allows for controlled passage of a pivot between a normally biased initial position and a task-performing position. The pivot includes a sheet-directing member and a track which is fixed relative to the sheet-directing member and is movable to the task-performing position in opposition to pivot bias. A follower, which is configured for selected travel along the track, selectively applies a force against the track in opposition to biased sheet-directing member movement. A processor-controlled printhead carriage is used to trigger and then to regulate pivot rotation.

Abstract: The invented printer includes a paper drive and mechanisms which hold paper in proper alignment in the drive. Specifically, it includes a pressure plate capable of bringing a sheet of paper into contact with a drive roller so that the paper is properly aligned, a wrapper which keeps paper in proper contact with the drive roller, a media edge contactor that presses against paper, a carriage guide support which helps to insure proper alignment of the paper during printing, and a back-out restraint to prevent paper from backing out of the printer.

Abstract: An improved paper feed arrangement wherein a low vertical profile is attained through utilizing trained driven belts for picking paper from a hopper, and wherein picking reliability is enhanced both by the broad-expanse area contact offered by such belts, and by a unique coefficient to friction differential area downstream from a hopper wherein inadvertently plural picked paper sheets are easily separated.