Lexmark International, Inc.

Jay William Vessels

Michael Anthony Marra, Iii

Christopher Alan Adkins

Barry Baxter Stout

John Thomas Writt

Michael William Lawrence

Adam Jude Ahne

Randall David Mayo

Patrick Laurence Kroger

Alexander Lloyd Chapman

A method for controlling the media feed of a print media sheet in an imaging apparatus having a media feed roller includes selecting between using absolute positioning of the media feed roller and relative positioning of the media feed roller for various media feed roller moves.

Method for controlling media feed in an imaging apparatus

An encoder and related methods for use in a printing device indexing system are provided. In some embodiments, the system comprises a feedroller or other component configured to index media through a printing device, and an encoder disk is coupled to the feedroller. In these embodiments, the system includes a reflective optical detector having a transmitter and a receiver provided adjacent a first surface of the encoder disk, the reflective optical detector being configured to detect the passage of the home position mark as the encoder disk rotates by the reflection of radiation off of the first surface. Also provided in some embodiments are methods for setting a counter to correspond with the home position of a rotatable element by utilizing threshold signal levels.

Methods and apparatuses for sensing rotational position of a component in a printing device

Methods and systems are provided for compensating for media indexing errors in a printing device. In one embodiment, the method comprises identifying a desired amount by which the print receiving medium should be indexed in order to print at the next location for the image being printed. The method further comprises determining an ideal indexing command for causing the indexing command based upon a compensation factor in order to compensate for imperfections in the indexing system. In this embodiment, the ideal indexing command is adjusted only once per indexing of the print receiving medium by the desired amount, and the adjusted ideal indexing command is utilized to move a roller and to index the receiving medium by the desired amount in order to print at the next location for the image being printed.

Methods and systems for compensation of media indexing errors in a printing device

In one aspect, in a device such as a printer, an encoder system method initializes the system to produce analog output signals that fall outside the detection range of an A/D converter of the system. In another aspect, in a device such as a printer, an encoder system method initializes the system without converting analog signal levels into corresponding digital values.

Encoder initialization methods and related systems

One method operates a pick motor and a separate feed motor to pick and feed a sheet for printing. Desired pick and feed motor velocities are obtained from respective first and second functions of sheet position. Sheet position for obtaining both desired motor velocities is determined by the pick system until a predetermined event. The feed-system sheet position is synchronized to the pick-system sheet position upon the happening of the event. Sheet position for obtaining both desired motor velocities is determined by the feed system after the event. Another method operates a printer pick motor and includes starting picking by driving the pick motor in a first direction, to move a sheet forward, with an input sufficient to prevent any teetering transitions between peaks and valleys of an encoder sensor output which would be falsely counted as forward motion by a single-channel encoder. A further method operates a printer DC pick motor and includes driving the pick motor with a PWM signal which does not change polarity during picking of a sheet.

Method for operating sheet pick and feed systems for printing

A method of analog encoder initialization involves repeatedly adjusting an encoder light element energization level and dc offsets of the encoder channels to produce desired signals.

Growing community of inventors

Lexington, KY, United States of America

Jay William Vessels