Thomas Edward Fields

US Patent:

7206012, Apr 17, 2007

Filed:

Mar 24, 2004

Appl. No.:

10/808043

Inventors:

William P. Cook - Lexington KY, US
Thomas A. Fields - Winchester KY, US
Allen P. Johnson - Lexington KY, US
Christopher D. Jones - Georgetown KY, US
Gregory L. Ream - Lexington KY, US

Assignee:

Lexmark International, Inc. - Lexington KY

International Classification:

B41J 2/47
B41J 2/435

US Classification:

347234, 347245

Abstract:

An optical scanner is provided having a memory device thereon. The memory device may store operational characteristics of the optical scanner or data that characterizes laser beam scan path and/or laser power requirements by each laser of the optical scanner. The memory device may be used to store historical information such as device temperature, cycles of operation and other historical information of components within a corresponding electrophotographic device. Still further, the electrophotographic device to which the optical scanner is installed may write operational data to the memory device, for example, to store a backup of registration and other operational parameters that are typically stored by the controller of the electrophotographic device.

US Patent:

7349123, Mar 25, 2008

Filed:

Mar 24, 2004

Appl. No.:

10/807870

Inventors:

Cyrus B. Clarke - Lexington KY, US
Thomas A. Fields - Winchester KY, US
Allen P. Johnson - Lexington KY, US
Christopher D. Jones - Georgetown KY, US

Assignee:

Lexmark International, Inc. - Lexington KY

International Classification:

H04N 1/40

US Classification:

358 19, 358504

Abstract:

Systems and methods are provided for characterizing laser beam process direction position errors in an electrophotographic device. Once the process direction position errors of a given beam laser beam system have been characterized, an image is adjusted or warped prior to being processed by the laser beam system to compensate for laser beam process direction position errors, e. g. , bow and skew.

US Patent:

7375738, May 20, 2008

Filed:

Mar 24, 2004

Appl. No.:

10/808155

Inventors:

William P. Corbett - Lexington KY, US
Thomas A. Fields - Winchester KY, US
Allen P. Johnson - Lexington KY, US
Christopoher D. Jones - Georgetown KY, US

Assignee:

Lexmark International, Inc. - Lexington KY

International Classification:

B41J 2/435
B41J 2/47

US Classification:

347234, 347248

Abstract:

Systems and methods are provided for electronically adjusting an image to compensate for laser beam process direction position errors in an electrophotographic device. Initially, a bow profile is defined that characterizes the process direction position errors of a laser beam across a scan line. The device subsequently reads an image to be printed from a first memory location, performs pixel shifts on select columns thereof based upon the bow profile, and temporarily stores the adjusted image data to a second location of memory. The adjusted image data is then communicated to a printhead of the device.

US Patent:

7633256, Dec 15, 2009

Filed:

May 4, 2005

Appl. No.:

11/121576

Inventors:

Brian Anthony Reichert - Lexington KY, US
Steven Michael Turney - Lexington KY, US
Danny Keith Chapman - Sadieville KY, US
Thomas Austin Fields - Winchester KY, US

Assignee:

Lexmark International, Inc. - Lexington KY

International Classification:

G05B 19/29

US Classification:

318602, 318638, 318651

Abstract:

Correction of rotary encoder eccentricity in an image forming device having a motor controller using period and position pulse train feedback signals. A motor includes an encoder disc rotating with the motor and at least two encoder sensors disposed at different circumferential positions about the encoder disc. A controller may use a high speed clock to calculate a corrected speed count based on speed counts determined from the number of clock cycles that elapse per cycle of pulse trains from the encoders. The controller may also calculate a corrected position count based at least partly on one or more position counts determined from the number of clock cycles that elapse between periodic sampling points and transitions of encoder pulse trains. The corrected position count may also be calculated based on a position count and one or more speed counts.

US Patent:

7639407, Dec 29, 2009

Filed:

Mar 24, 2004

Appl. No.:

10/808130

Inventors:

Cyrus B. Clarke - Lexington KY, US
William P. Corbett - Lexington KY, US
Thomas A. Fields - Winchester KY, US
Christopher D. Jones - Georgetown KY, US

Assignee:

Lexmark International, Inc. - Lexington KY

International Classification:

H04N 1/04

US Classification:

358474, 358 19, 358 12, 358 115, 358406, 347132, 347246, 347236

Abstract:

Laser beam scan line nonlinearity is compensated for by providing algorithms for generating linearity profiles which are used by a corresponding registration system in an electrophotographic device to determine the placement of Pels across a scan line.

US Patent:

20090185197, Jul 23, 2009

Filed:

Jan 22, 2008

Appl. No.:

12/017554

Inventors:

Michael Hayes Wilson - Lexington KY, US
William Paul Cook - Lexington KY, US
Thomas Austin Fields - Winchester KY, US
Daniel L. Carter - Georgetown KY, US

International Classification:

G06F 3/12

US Classification:

358 11

Abstract:

The present application is directed to methods and devices for controlling a motor in an image forming device by sensing the amount of current applied to the motor. One embodiment includes a power supply operatively connected to a controller. The power supply provides an electrical current to a motor, and the amount of current is measured. The controller monitors the amount of current and determines an operating condition of the motor based on the current. The controller may then continue to allow the power supply to provide the electrical current to the motor, or may shut off the current based on the operating condition. The controller may also monitor a timer to determine how long the power supply has provided current to the motor. In one embodiment, the controller may use both the signal and monitored time to determine the operating condition of the motor.

US Patent:

20100072938, Mar 25, 2010

Filed:

Nov 30, 2009

Appl. No.:

12/627790

Inventors:

Brian Anthony Reichert - Lexington KY, US
Steven Michael Turney - Lexington KY, US
Danny Keith Chapman - Sadieville KY, US
Thomas Austin Fields - Winchester KY, US

Assignee:

LEXMARK INTERNATIONAL, INC. - Lexington KY

International Classification:

G05B 1/06
G01D 5/30

US Classification:

318640, 25023113

Abstract:

Correction of rotary encoder eccentricity in an image forming device having a motor controller using period and position pulse train feedback signals. A motor includes an encoder disc rotating with the motor and at least two encoder sensors disposed at different circumferential positions about the encoder disc. A controller may use a high speed clock to calculate a corrected speed count based on speed counts determined from the number of clock cycles that elapse per cycle of pulse trains from the encoders. The controller may also calculate a corrected position count based at least partly on one or more position counts determined from the number of clock cycles that elapse between periodic sampling points and transitions of encoder pulse trains. The corrected position count may also be calculated based on a position count and one or more speed counts.