Hewlett-packard Company

Larry A Jackson

Steve Orrin Rasmussen

Kieran B Kelly

J P Harmon

David W Pinkernell

Thomas E McCue, Jr

John D Rhodes

Thomas W Ruhe

Kevin D O'Hara

Jeffrey R Blackman

William Richard Huseby

Larry G Neubauer

Kevin Loren Moon

Henry Young Chin

Jan Hippen

Daniel R Dwyer

Alan Shibata

Richard Alan Kelley

Bruce Alan McFadden

Donald R McClelland

Donald R Bloyer

David M Thorpe

Craig D Sunada

John A Christianson

Richard E Berriman

Sandra Y Okazaki

Jeffrey G Patrick

David W Pinkerpell

Juli K Noble

Stephen D Dorow

Stephen C Brown

A modular duplex media handling system is installable for use with a print recording system having a simplex media handling system. During first side printing a media sheet is fed along a first media path in the simplex system from feed rollers to metering rollers and into a print zone. After first side printing and prior to releasing the media sheet, the metering rollers feed the media sheet back along the first media path to the feed rollers. The feed rollers in turn feed the media sheet completely into the duplex module where the media moves along a loop path (in effect flipping the media sheet). The media sheet then is fed back to the feed rollers and along the first media path for second side printing. A humidity sensor in the duplex module signals to the print recording system whether the duplex handling system is installed.

Print recording apparatus having modular autoduplex mechanism

A sheet media handling system is provided for use in supporting a sheet ejected from a wet-ink hard copy apparatus output port while ink on a preceding sheet ink an output tray is allowed time to dry before depositing the succeeding on top thereof. The system employs a pair of guides having an elongate channel therebetween which receives a predetermined side edge of an ejected sheet. The channel bends the sheet in order to stiffen the sheet along its longitudinal axis such that only one edge need be supported. Once a trailing edge of an advancing sheet is ejected from the output port, a lower guide is retracted whereby the sheet falls under the force of gravity onto the output media stack in the output tray. Several advantageous lower guide upper surface constructs are disclosed. The advantages of the use of a guide mechanism on each side of the advancing output sheets is discussed.

Wet-print cut-sheet media handling system

A media handling system includes a drive roller, an elongated pinch roller and a contoured support. The pinch roller extends across the print medium near the print zone to control the localized shape of the print medium. The support underlies the print medium in the print zone and includes first and second underlying pivotal inclines. The pinch rollers push the print medium onto the first pivotal incline adjacent to the drive roller. The second underlying incline is located downstream toward the print zone exit. As the print medium is fed through the print zone, a portion of the print medium within the print zone between the pivotal inclines is suspended exhibiting a reverse bowing. Beyond the second pivotal incline the print medium droops. The presence of the two underlying inclines more uniformly distributes the stress accompanying the bowing of the print medium within the print zone.

Print media handling system including dual incline support for

A method and apparatus for advancing a sheet of print media through a printer mechanism having a print zone. The apparatus includes a roller assembly for advancing a sheet of media through the print zone, a printing assembly for recording information on a surface of the sheet of media and an assembly for receiving the sheet of media once information has been recorded on the sheet of media. The apparatus includes a kicker which is movable in the forward direction to engage an edge of the sheet of media to urge the sheet in a forwardly direction from the print zone to the receiving assembly. The method of this invention includes the step of pushing the edge of the sheet of media towards the receiving assembly.

Method and apparatus for paper control including kickers

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. To facilitate ejection of printed pages, the upper print medium guide is formed with a series of ribs which contact the paper. The ribs reduce friction and static buildup, and make it easier to push the paper from the paper transport mechanism.

Media handling in an ink-jet printer having guide ribs

Color inkjet printer

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.

Media handling in an ink-jet printer

A method for correcting the skew between the leading edge of a sheet of paper and the nip of a roller assembly in a printing mechanism includes the steps of advancing a sheet of paper into the nip and slightly therebeyond. The rollers are then rotated in reverse, causing the paper to retract from the roller assembly, with the angle and weight of the paper maintaining the leading edge within the nip. As the rollers continue to rotate backwards, the paper jiggles or dances allowing the leading edge to settle parallel with the nip under its own weight. The paper is then readvanced through the roller assembly with its leading edge parallel to the nip. A mechanism applies a drag force to the paper when the paper is being retracted from the roller assembly to keep the leading edge of the paper in the nip. A single motor control apparatus includes a processor-controlled drive motor, a drive roller assembly, a pick roller assembly and a gearing arrangement coupling the drive motor to the roller assemblies, for selective control of the timing, speed and rotational direction thereof to achieve the above described method.

Method and apparatus for paper control and skew correction in a printer

An apparatus for control of a sheet of paper in a printer mechanism includes a single motor drive mechanism, a frame, a platen, a roller assembly for advancing the sheet of paper over the platen, and a kicker element for selectively contacting only an edge of a sheet of paper and for urging the sheet of paper in a forward direction once it is forwardly disengaged from the roller assembly.

Method and apparatus for paper control in a printer

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.

Paper feed arrangement

A printhead cartridge and carriage assembly (10) is provided comprising: a carriage (12); a snap-spring (62) for securing a printing cartridge (14) in postion on the carriage; and an interconnect strip (16) for supplying electrical signals to the cartridge, including a force loading spring pad (24) for urging a portion of the interconnect strip against a portion of the cartridge. The cartridge has top (32), bottom (34), sides (36, 38), front (40) and rear (42) surfaces and includes a printhead (44) on the bottom surface, an electrical contact strip (46) on the back surface connected to the printhead, referencing pads (56) on the side surface, and a lip (64) on the back surface for accepting the snap-spring. Referencing surface (60) are provided for receiving the referencing pads on the cartridge. The spring pad urges the interconnect strip against the electrical contact of the cartridge. The printhead cartridge/carriage assembly of the invention requires only one hand of the operator to both insert and lock the cartridge in position. Further, the cartridge/carriage assembly provides simultaneous alignment of the printhead in the X, Y, and Z directions. Finally, contact between the printhead and the interconnect strip is reliably made each time the cartridge is inserted and locked in position, thereby ensuring proper nozzle firing each time.

Printhead-carriage alignment and electrical interconnect lock-in

A novel ink-jet printer (10) is provided. The print provides both paper supply tray (12) and paper collection tray (18) in the front (14) of the printer for ease of paper handling and reduced footprint. The paper collection tray is provided with a pair of opposed output rails (22) which support a sheet of paper (16c) during printing to permit ink on a sheet of paper (16b) previously printed to dry. A paper handling mechanism is provided which eliminates a sheet pickup motor and associated elements. The paper handling mechanism is configured to pick off a sheet of paper from a stack of input paper, bring it around paper drive rollers (24) onto a platen (26), where the printing operation, employing a printhead cartridge (32), occurs. The printer further includes a service station (230) for clearing clogged nozzles in the printhead (33) and removing bubbles therefrom, for covering the nozzles with a protective cap (266), and for wiping contaminants off the nozzles. Reference pads (200) are provided for aligning and securing the printing cartridge in a carriage (35). The carriage is associated with a carriage guide (27), to which the carriage and print medium are referenced. The resulting printer is easy to manufacture, has reduced complexity by eliminating components in the paper drive mechanism and is lower in cost.

Ink-jet printer with printhead carriage alignment mechanism

Several problems of alignment associated with ink-jet printers are alleviated by four aspects. In the first, a reverse bow (B) in the paper (12) is created for printing on single sheets of paper. The reverse bow, which in the transverse axis of the paper, forces the paper flat against the platen (14) by using the paper's own stiffness. In the second aspect, the paper and the carriage (30) are referenced to the same part (the carriage guide (10)). In this configuration, the paper is urged against the underside of the carriage guide off of drive rollers (18), through the reverse bow, and onto the platen, where it is printed. The carriage is referenced to the carriage guide through a slider bump by means of a carriage shaft and gravity. The carraige guide comprises stiff thin sheet metal, which is closely-toleranced and has well-controlled dimensions. Thus, this part is good to reference to, rather than molded-in parts, which are not stiff enough at the required thickness. Straightness is also difficult to achieve at the required thickness with plastic parts. In the third aspect, the platen is allowed to move substantially perpendicular to the plane of the paper to accommodate thicker print media. In the fourth aspect, the platen is maintained a minimum fixed distance from the carriage guide by bumps (38) to ensure that the paper is not pinched between the carriage guide and the platen.

Ink-set printhead-to-paper referencing system

An active paper drop mechanism (20) for ink-jet printers is provided. The mechanism comprises a pair of opposed, movable rail members (22) associated with opposed walls (14) of a horizontal-disposed output collection tray (12) for receiving sheets (10) of printed media. In particular, each rail member is provided with return spring (26) that act to maintain the rails in a closed position. In that position, the rails support a sheet of the print medium during the printing operation, thus giving the ink on the previously printed-on sheet (10') time to dry. The rails are provided with a wing member (32) and are pivotally secured (38) in the floor of the output tray, with the pivot point spaced inwardly from the wing member. Downward pressure against the wing member thus causes the rail to rotate outward from its closed position, into a recess (24) provided in the side of the output tray. This provides sufficient clearance for the sheet to drop into the output stack. Upon release of the downward pressure, the spring causes the rail member to return to its original closed position.

Growing community of inventors

Vancouver, WA, United States of America

Larry A Jackson