Hewlett-packard Company

Hewlett-packard Development Company, L.p.

Rick Minoru Tanaka

Dan Arquilevich

Steven B Elgee

Christopher M Lesniak

Jason Grosse

Brent A Geske

John A Underwood

Algird M Gudaitis

Donald R Bloyer

Charles S Woodruff

Braulio Soto

Alan Shibata

Justin M Roman

Sam Michael Sarmast

Richard Alan Kelley

Anthony Peter Carcia

Ronald A Juve

Edward L Feldhousen

Ernesto A Garay

David K Klaffenbach

Angela Chen Krauskopf

Tanya Schneider

Elmer Samov Cajigas

Matias Negatu

Charles W Singleton, Jr

Shayler M Backlund

Wade Antoine Powell

A system is provided that includes an encoder strip having encoder markings, first and second optical encoders positioned at a fixed distance from one another on a substrate and, responsive to being moved along the encoder strip, configured to generate first and second signals, respectively, that each indicate detection of the encoder markings on the encoder strip and processing circuitry configured to determine a current phase difference between the first and the second signals using a first portion of the first signal that corresponds to a first plurality of encoder markings and a second portion of the second signal that corresponds to a second plurality of encoder markings.

Determining encoder strip expansion

Disclosed are apparatus and methods for compensating for the change in length of an encoder strip due to environmental effects such as temperature and humidity. The apparatus and methods utilize two simple optical sensors spaced apart and mounted on a substrate having a different coefficient of thermal expansion than the encoder strip; the substrate is mounted to the movable component which is to be positioned, such as a printer carriage. Embodiments of the methods utilize information from the two sensors, in conjunction with information from the analog encoder used to position movable component, to compensate for environmental effects.

Apparatus and methods for compensation of thermal and hydroscopic expansion effects in a low cost motion control system

Embodiments of uniquely spaced markings are disclosed.

Uniquely spaced markings

Systems and methods are disclosed for carriage positioning.

Carriage positioning

Various embodiments of a printing system including a vacuum duct are disclosed.

Printing system and method

A lubricating system includes a flexible, nominally planar lubricating structure including first and second end regions and a central region positioned therebetween. The lubricating structure is impregnated with a lubricating fluid and is adapted for securement to a printhead carriage only at said first and second end regions.

Lubricating system including a lubricating structure

Two motors are used to provide motion control in a transport drive system. A primary motor, or a primary and secondary motor, provides primary power for accelerated motion. PWM signals are used to drive the motors according to predetermined fixed functions related to acceleration, deceleration and hold of a load. Alternatively, during onset of large or high speed moves, the primary and secondary motors are on in tandem. During deceleration of a move, the torque provided by the secondary motor is reversed, providing active braking and ensuring the drive train remains loaded wherein backlash is eliminated. During a driver hold phase, the primary and secondary motor push against each other to actively control positioning.

Active damping and backlash control for servo systems

Printing apparatus that employs a media detect switch and a linear optical detector to accurately detect the leading edge or trailing edge of a print medium to modify print data so that printing does not extend off the print medium beyond the leading edge or trailing edge. Also disclosed are techniques for using the media detect switch to control a media advance operation to position the leading edge or trailing edge of the print medium in the field of view of the linear array optical detector.

Techniques for using a linear array to detect media top/bottom edges for full bleed printing

Edge to edge printing techniques for reducing overspray beyond lateral edges of a print medium.

Full bleed printmode to minimize overspray

A method and apparatus for automatic alignment of ink-jet printheads includes fitting measuring constructs to actual print data acquired form a print made using a given, predetermined, test pattern data set. Specific test patterns for use in automated alignment of ink-jet printheads are suited to providing a variety of printhead alignment information in a compact format. The test pattern data set incorporates techniques for avoiding carriage-induced dynamic errors during automated alignment of ink-jet printheads.

Automated ink-jet printhead alignment system

A method and apparatus for automatic alignment of ink-jet printheads includes fitting measuring constructs to actual print data acquired form a print made using a given, predetermined, test pattern data set. Specific test patterns for use in automated alignment of ink-jet printheads are suited to providing a variety of printhead alignment information in a compact format. The test pattern data set location finding algorithm incorporates techniques for avoiding carriage-induced dynamic errors during automated alignment of ink-jet printheads.

Peak-valley finder process for scanned optical relative displacement measurements

Optical encoder system and method for use in printing devices

A method and means for automatic alignment of ink-jet printheads includes fitting measuring constructs to actual print data acquired form a print made using a given, predetermined, test pattern data set. Specific test patterns for use in automated alignment of ink-jet printheads are suited to providing a variety of printhead alignment information in a compact format. The test pattern data set incorporates techniques for avoiding carriage-induced dynamic errors during automated alignment of ink-jet printheads.

A print media ejection system actively pushes a media sheet trailing edge into an output tray. The ejection system includes a movable pivot which supports a media sheet within a print zone during printing. Upon completion of printing the pivot moves downward allowing the current media sheet to slide from the pivot into the output tray. After the pivot completes the downward rotational stroke, the pivot rotates back upward to be in position to support the next media sheet. The upward motion of the pivot mechanism actuates a kicker device to rotate toward an output region. The kicker device drives any remaining portion of the media sheet into the output tray.

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Vancouver, WA, United States of America

Rick Minoru Tanaka