Patents by Inventor John P. Richey

John P. Richey has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10001732
    Abstract: A system and method for controlling the fuser assembly of an electrophotographic imaging device, including determining a resistance of the fuser heater at a predetermined temperature that is less than a fusing temperature for performing a fusing operation; calculating a set point heater resistance based on the determined heater resistance, the set point heater resistance being a resistance of the fuser heater at a predetermined set point temperature; reading a line voltage to the electrophotographic imaging device at a first time; calculating heater power based on the line voltage reading and the calculated set point heater resistance; and controlling a speed of a fusing operation based on the calculated heater power.
    Type: Grant
    Filed: February 8, 2017
    Date of Patent: June 19, 2018
    Inventors: Jichang Cao, Christopher E. Rhoads, John P. Richey, David Anthony Schneider, Daniel Steinberg
  • Publication number: 20170192379
    Abstract: A system and method for controlling the fuser assembly of an electrophotographic imaging device, including determining a resistance of the fuser heater at a predetermined temperature that is less than a fusing temperature for performing a fusing operation; calculating a set point heater resistance based on the determined heater resistance, the set point heater resistance being a resistance of the fuser heater at a predetermined set point temperature; reading a line voltage to the electrophotographic imaging device at a first time; calculating heater power based on the line voltage reading and the calculated set point heater resistance; and controlling a speed of a fusing operation based on the calculated heater power.
    Type: Application
    Filed: February 8, 2017
    Publication date: July 6, 2017
    Inventors: Jichang Cao, Christopher E. Rhoads, John P. Richey, David Anthony Schneider, Daniel Steinberg
  • Patent number: 9639038
    Abstract: A system and method for controlling the fuser assembly of an electrophotographic imaging device, including initiating reading line current and line voltage for a plurality of consecutive AC cycles; from the AC cycle readings, identifying heater on cycles in which power is applied to the fuser heater and heater off cycles in which power is not applied to the fuser heater; calculating heater power from the identified heater on cycles and the heater off cycles, the heater power being the power of the fuser heater during a predetermined heater on cycle of the consecutive AC cycles; calculating a fuser heater voltage of the fuser heater during the predetermined heater on cycle based on the voltage readings; calculating a resistance of the fuser heater based on the calculated heater power and the calculated fuser heater voltage; and controlling the fuser assembly based upon the calculated resistance of the fuser heater.
    Type: Grant
    Filed: December 31, 2015
    Date of Patent: May 2, 2017
    Assignee: LEXMARK INTERNATIONAL, INC.
    Inventors: Jichang Cao, Christopher E. Rhoads, John P. Richey, David Anthony Schneider, Daniel Steinberg
  • Patent number: 7515646
    Abstract: An improved data signal electromagnetic emissions system is provided for sending data signals over one or more data pathways. An original data signal is encoded into a set of sideband frequencies that exhibit a lower amplitude than the original data signal; then transmitted over the data pathway and later decoded back into a signal having the original data content. The encoding scheme uses a number of modulation pattern sets that each produce a set of sidebands about the data signal's fundamental and certain harmonic frequencies, in a manner that attempts to make the maximum amplitudes for each set of sidebands substantially equal to one another, although this is also dependent upon the data signal's frequency content.
    Type: Grant
    Filed: February 5, 2004
    Date of Patent: April 7, 2009
    Assignee: Lexmark International, Inc.
    Inventors: Keith B. Hardin, Robert A. Oglesbee, John P. Richey
  • Patent number: 7433630
    Abstract: Drive train motor speed is varied in a manner that compensates for characteristic rotational velocity errors of the associated drive train, such as by modulating a drive train motor speed control signal at a modulation phase and amplitude derived from the characterized rotational velocity error. Characterization can be performed on a test system for each drive train of interest, and the compensation values thus obtained can be saved for later use by systems in which the characterized drive trains are used. Thus, a drive train used in a consumables cartridge for an electrophotographic printing (EP) system can be characterized and the corresponding data saved via a label or memory circuit that is affixed to the cartridge. Such data can be used by the EP system in which the cartridge is installed to more accurately control the velocity of the image forming process members driven by the cartridge's characterized drive train.
    Type: Grant
    Filed: December 14, 2004
    Date of Patent: October 7, 2008
    Inventors: Stacy M. Pargett, Mark A. Omelchenko, John P. Richey, John Spicer, Adrian J. Lee
  • Patent number: 7277111
    Abstract: An electrophotographic device comprises a printhead having at least one laser associated with a corresponding photoconductive surface. Where multiple laser beams are associated with the same photoconductive surface, the laser beams are spaced a predetermined distance from one another in a process direction, which is orthogonal to a scan direction in which the laser beams are swept. The electrophotographic device operates at one of at least two image transfer rates. A controller in the electrophotographic device selectively directs image data to the printhead based, at least in part, upon the selected image transfer rate, the facet resolution, and/or the desired output image resolution. The print speed can thus be adjusted over a relatively wide range.
    Type: Grant
    Filed: January 28, 2005
    Date of Patent: October 2, 2007
    Assignee: Lexmark International, Inc.
    Inventors: Alan S. Campbell, Cary P. Ravitz, John P. Richey
  • Patent number: 6661981
    Abstract: Transfer belt subassembly for a color printer includes a transfer belt, home position indicator, temperature sensor, and memory. The transfer belt subassembly is measured and characterized after fabrication, before being installed in a printer. Measurement and calibration data for the transfer belt is stored in memory as part of the subassembly, including data representing velocity characteristics of the transfer belt and temperature compensation factors used by an engine-controller in a method to govern the speed of the drive motor. When the transfer belt subassembly is inserted into a printer, the engine-controller is operative in response to data stored in the memory and sensed belt velocity and temperature data, providing adjustment of belt velocity and compensation for variations in the transfer belt speed. Using the predetermined characterizing data, precise alignment of the color planes with respect to one another is achieved for accurate color printing.
    Type: Grant
    Filed: October 15, 2001
    Date of Patent: December 9, 2003
    Assignee: Lexmark International, Inc.
    Inventors: Richard M. Boothe, Danny K. Chapman, Mark A. Omelchenko, Gregory L. Ream, John P. Richey
  • Publication number: 20030072578
    Abstract: A transfer belt subassembly for a color printer includes a transfer belt, a home position indicator, a temperature sensor and a memory. The transfer belt subassembly is measured and characterized after it fabrication and before being installed in a printer. The measurement and calibration data for the transfer belt is stored in the memory that is part of the subassembly. The memory stores data representing the velocity characteristics of the transfer belt and temperature compensation factors for use by a engine-controller of the printer to govern the speed of the drive motor. When the transfer belt subassembly is inserted into a printer, the engine-controller is operative in response to data stored in the memory and sensed belt velocity and temperature data to provide adjustment of belt velocity and compensation for variations in the transfer belt speed. By use of the predetermined characterizing data, precise alignment of the color planes with respect to one another is achieved for accurate color printing.
    Type: Application
    Filed: October 15, 2001
    Publication date: April 17, 2003
    Inventors: Richard M. Boothe, Danny K. Chapman, Mark A. Omelchenko, Gregory L. Ream, John P. Richey
  • Patent number: 6366174
    Abstract: An improved clock generation circuit is provided that operates with a single input clock frequency, and includes a Phase Locked Loop circuit (PLL) with a digital accumulator in the feedback loop, in which either the Most Significant Bit or the Carry Bit of the binary adder is used as the modulated feedback clock to the phase/frequency detector of the PLL. In one embodiment, a fixed add/phase amount is used to drive one of the inputs of the binary adder to generate a fixed output frequency. If it is desired to modulate the output frequency, then an Add Amount Modulator circuit can be provided that presents a varying numeric value to one of the inputs of the binary adder. The MSB or Carry Bit is communicated to an address look-up table, which then outputs an address to a memory circuit, which in turn presents a different add amount to the binary adder.
    Type: Grant
    Filed: February 21, 2000
    Date of Patent: April 2, 2002
    Assignee: Lexmark International, Inc.
    Inventors: John B. Berry, James R. Booth, Keith B. Hardin, John P. Richey