Hewlett-packard Company

Hewlett-packard Development Company, L.p.

Todd R Medin

Brent W Richtsmeier

William D Meyer

Todd L Russell

John A Underwood

Peter C Morris

Raymond M Cundiff

Steve Orrin Rasmussen

Stephen William Bauer

Geoff Wotton

Richard Alan Kelley

Shelley I Moore

Steven B Elgee

Alan Shibata

Damon W Broder

Le Gia Pham

Kevin L Glassett

Dale R Davis

Craig S Huston

Said Zamani-Kord

Bruce E Mortland

Richard A Becker

Bruce E Mueller

Kenneth J Knight

Mark G Wisnosky

John A Barinaga

Eric Joseph Johnson

William H Schwiebert

Arthur King Wilson

Robert R Giles

Abdolreza Movaghar

James O Beehler

Antoni Murcia

Stephen B Witte

Gary M Nobel

Michael S Millman

Patricia S Brown

Dean A Gaylor

Tanya Vesta Burmeister

Richard M Kemplin

Anthony W Ebersole

John Thomas

Michael Payne

A method of one embodiment of the invention is disclosed that determines a property of air within an image-forming device based on a measured change in air temperature within the device, the power supplied to a heating element of the device, and an air flow generated by an air-moving device. One or more parameters of the image-forming device are adjusted, based on the air density determined.

Property of air determination within image-forming device

A print medium is encoded with information bearing indicia. A transparent layer or substrate which receives the printed information during printing has a first surface, a second surface and a leading edge. A strip of tape is applied to the first surface. A machine readable information bearing indicia is applied to at least one surface of the tape strip. The indicia is formed by a pattern of fluorescent material which upon excitation by radiation of a given spectral excitation range emits radiation in a fluorescent spectral range. The tape reflects radiation in the given excitation spectral range and in the fluorescent spectral range. One type of indicia is a bar code pattern, although other types can also be employed.

Tape indicia on clear film media

A print media preheating method and apparatus uses heat, vacuum, and mechanisms for drying and flattening a sheet prior to ink-jet printing thereon. Pre-shrinking the media, driving out and substantially reducing inherent moisture content prior to depositing wet ink thereon provides greater flatness in the print-zone whereby ink-jet print quality is improved.

Print media heating techniques for a vacuum belt hard copy apparatus

A pick mechanism includes a hinged pick arm which moves between a retracted position and a varying, operating position. The pick arm is anchored about a pivot axis and hinged along its length. Rotation of a pick roller along the arm while in contact with a media sheet induces a moment on the pick arm causing the pick arm to pivot and hinge. A first stop limits the pivoting motion. A second stop limits the hinging motion, Such pivoting and hinging is desirable to create an effective normal force enabling reliable picking of thick media sheets. Such motions are limited to prevent the pick roller from translating too far from a media separation ramp. If the pick roller translates too far, undesirable media buckling may occur during the pick operation.

Hinged-arm pick mechanism

A pick mechanism includes a hinged pick arm which moves between a retracted position and a varying, operative position. The pick arm is anchored about a pivot axis and hinged along its length. Rotation of a pick roller along the arm while in contact with a media sheet induces a moment on the pick arm causing the pick arm to pivot and hinge. A first stop limits the pivoting motion. A second stop limits the hinging motion. Such pivoting and hinging is desirable to create an effective normal force enabling reliable picking of thick media sheets. Such motions are limited to prevent the pick roller from translating too far from a media separation ramp. If the pick roller translates too far, undesirable media buckling may occur during the pick operation.

A method for determining a present air density for an imaging mechanism is presented. During a first time period: in a determining and storing action, a nominal air density is stored. In an increasing action, a fan input is increased until a known pressure in a cavity coupled to a fan receiving the fan input has been reached. In a determining and storing action, a nominal fan parameter is determined and stored after the known pressure is reached. During a second time period: in an increasing action, the fan input is increased until the known pressure in the cavity has been reached. In a determining action, a present fan parameter is determined after the known pressure is reached. In a calculating action, the present air density is calculated from the present fan parameter, the nominal fan parameter, and either the known pressure or the nominal air density.

Method for determining air density

A flipping wiper scraper system for cleaning several inkjet printheads in an inkjet printing mechanism has a wiper support mechanism which moves several elastomeric wipers across the printheads to wipe off accumulations of ink residue. This ink residue is then scraped off of the wipers to ready them for the next wiping stroke using a scraper system. The wiper support mechanism inverts the wipers to engage scraper bars of the scraper system. The scraper bars have scraping heads and capillary channels to draw liquid ink residue away from the heads through capillary forces. The scraper bars are arranged so only one or two wipers are scraped at any given time to reduce noise and quiet overall unit operation. A method of cleaning an inkjet printhead, along with an inkjet printing mechanism having such a flipping wiper scraper system are also provided.

Flipping wiper scraper system for inkjet printheads

An inkjet printhead service station for an inkjet printing mechanism includes a printhead wiping system having a wiper blade with a contoured cross sectional shape selected to impart a lower wiping force along an ink-ejecting nozzle region of the printhead than along side regions of the printhead. In a relaxed state, the blade has opposing leading and trailing surfaces, with each surface having a concave contour running along at least a portion of the length of the blade, preferably from the support sled to the wiping tip. During a wiping stroke, the blade flexes along both the length and width of the blade, with the trailing surface having a greater degree of concavity than when relaxed, and the leading surface having a linear contour at the wiping tip and tapering into the concave contour adjacent the sled. An inkjet printing mechanism having such a wiping system, and a method of cleaning a printhead are provided.

Contoured cross-sectional wiper for cleaning inkjet printheads

An ink-jet hard copy apparatus provides a flow of air across the printing surface of a sheet of print media during printing operations. The airflow scrubs the boundary layer of the printing surface such that paper cockle is reduced by resultant improvement in drying time. A writing instrument deflector is used to prevent substantial interference with ink droplet flight trajectories due to positive airflow through the print zone.

Method and apparatus for ink-jet print zone drying

An ink solvent application system applies an inkjet ink solvent with a wiper to clean ink residue from an inkjet printhead. The solvent is stored in a porous applicator and extracted using capillary forces generated when the wiper is rubbed across the applicator. To retain sufficient amounts of ink solvent on the wiper, the wiper moves away from the applicator in a coordinated motion having both rotational and translational components. This coordinated motion for picking solvent from the applicator is superior to a purely rotational stroke of the wiper, which picks very little solvent. The wiper then wipes the solvent across the printhead to dissolve accumulated ink residue. The wiper then moves across a blotter to remove dissolved ink residue and dirty solvent from the wiper. A method of cleaning ink residue from an inkjet printhead, along with an inkjet printing mechanism having such a solvent application system, are also provided.

Ink solvent application system for inkjet printheads

An approach for managing the thermal stresses introduced into a heated belt of the type used for transporting media through an ink-jet printer so that the portion of the belt that transports the print media through the print zone does not buckle. The temperature of the belt is controlled to ensure that any temperature gradient produced in the belt is not great enough to buckle the belt in the print zone. Put another way, the temperature profile in the belt is substantially flat. As another approach to the present invention, the belt is bent in the print zone to create a force component in the belt for resisting thermal stress and to increase the belt area moment to greatly enhance resistance to buckling of the belt.

Buckling control for a heated belt-type media support of a printer

A replaceable inkjet printhead cleaner service station system has separate replaceable cleaning units for each printhead in an inkjet printing mechanism, which has a pallet that moves the cleaning units translationally to service the printheads. Each cleaning unit has a printhead wiper, a printhead snout wiper, a capping system, a spittoon, and optionally, an ink solvent application system. The application system has a reservoir body impregnated with an ink solvent, and a solvent distribution member including a unitary applicator wick having a ramped portion located to apply the ink solvent to the printhead when an edge of the printhead is brought into contact with the wick. A wick support spring is preloaded to supply a substantially consistent amount of ink solvent to the printhead, regardless of vertical spacing or tolerance variations therebetween. A method is provided for cleaning an inkjet printhead, along with a printing mechanism employing such a system.

Replaceable inkjet ink solvent application system

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Vancouver, WA, United States of America

Todd R Medin