Lexmark International, Inc.

Ryan David Brockman

Kerry Leland Embry

Robert Reed Booth

Claudia Alexandra Marin

Paul Wesley Etter

Travis Alan Riggs

William Paul Cook

Gregory Lawrence Ream

Larry Steven Foster

Jeffrey Lawrence Tonges

Pramod K Sharma

Kermit Arnold Meece

Michael Hayes Wilson

The present application is directed to methods of controlling the transfer voltage in a transfer nip formed between the photoconductive member and the transfer member. The methods offset the effects of large transfer current spikes caused when a media sheet enters and exits the transfer nip and account for temperature and humidity operating parameters using wet-bulb temperature measurements to adjust the transfer voltage. The control may include either ramping up or ramping down the transfer voltage. The ramped transfer voltage may include a series of alternating positive and negative steps that generally trend to ramp up or down. The size of the steps may further be adjusted to provide a smooth transition.

Method for adjusting transfer voltage controls based on environmental conditions to improve print quality in a direct transfer image forming device

The present application is directed to methods for transitioning between color printing and black-only printing in an image forming device. A cartridge is moved between a first position in which color printing may occur and a second position in which black-only printing may occur. In the first position, a color developer unit may be in contact with a color photoconductor unit. The color developer unit may be spaced from the color photoconductor unit in the second position. During the transition, a voltage supplied to the cartridge and a speed of a drive motor driving the cartridge may be adjusted.

Methods to control transitions between color printing and black-only printing in an image forming device

A system for adjusting selected operating parameters of an image forming device to improve color registration based on selected environmental conditions includes a first image forming station to print a first registration mark on a substrate, a second image forming station to at least partially erase the first registration mark to form a registration pattern in a reverse transfer process of the color registration, and a control mechanism to adjust voltage biases of charge and developer rolls of the second image forming station based on wet-bulb temperature values determined from measured dry-bulb temperature and relative humidity values and stored in a lookup table so as to maintain a predetermined potential difference between charged and uncharged areas of a PC drum of the second image forming station that avoids Paschen breakdown and the development of toner at charged areas of the PC drum during the reverse transfer process of the color registration.

System and method for adjusting selected operating parameters of image forming device based on selected environmental conditions to improve color registration

The present application is directed to methods of controlling the transfer voltage in a transfer nip formed between the photoconductive member and the transfer member. The methods offset the effects of large transfer current spikes caused when a media sheet enters and exits the transfer nip. The control may include either ramping up or ramping down the transfer voltage. The ramped transfer voltage may include a series of alternating positive and negative steps that generally trend to ramp up or down. The size of the steps may further be adjusted to provide a smooth transition.

Methods for transfering toner in direct transfer image forming

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Lexington, KY, United States of America

Ryan David Brockman