Patents by Inventor Robert Wilson Cornell

Robert Wilson Cornell 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).

  • Publication number: 20080001993
    Abstract: A substantially planar fluid ejection actuator and methods for manufacturing substantially planar fluid ejection actuators for micro-fluid ejection heads. One such fluid ejection actuator includes a conductive layer adjacent to a substrate that is configured to define an anode segment spaced apart from a cathode segment. A thermal barrier segment is disposed between the anode and cathode segments. A substantially planar surface is defined by the anode segment, and the thermal barrier segment. A resistive layer is applied adjacent to the substantially planar surface.
    Type: Application
    Filed: June 29, 2006
    Publication date: January 3, 2008
    Inventors: Robert Wilson Cornell, Yimin Guan, Burton Lee Joyner
  • Patent number: 6890062
    Abstract: A heater chip has a plurality of heaters each having a length, width and thickness. The length multiplied by the width (heater area) is in a range from about 50 to about 500 micrometers squared while the thickness is in a range from about 500 to about 5000 or 6000 angstroms. The energy required to jet or emit a single drop of ink from the heater during use is in a range from about 0.007 to about 0.99 or 1.19 microjoules. The heater chip is formed as a plurality of thin film layers on a substrate. Energy ranges are taught for all heaters having an area from about 50 to about 4000 micrometers squared and thicknesses ranging from about 500 to about 16,000 angstroms. Printheads containing the heater chip and printers containing the printheads are also disclosed.
    Type: Grant
    Filed: July 15, 2003
    Date of Patent: May 10, 2005
    Assignee: Lexmark International, Inc.
    Inventors: Byron Vencent Bell, Robert Wilson Cornell, Yimin Guan
  • Patent number: 6886921
    Abstract: An improved ink jet printer ejector including a substantially decahedral-donut shaped thin film resistor having a first end, a second end opposite the first end, a major axis having a first length, and a minor axis having a second length less than the first length. The major axis extends between the first end and the second end thereof. Electrical conductors are attached to the first end and to the second end of the resistor for activating the ink ejector on command from the ink jet printer. Decahedral-donut shaped thin film resistors exhibit improved heating characteristics and lower power consumption than conventional heater resistors.
    Type: Grant
    Filed: April 2, 2003
    Date of Patent: May 3, 2005
    Assignee: Lexmark International, Inc.
    Inventor: Robert Wilson Cornell
  • Patent number: 6834941
    Abstract: A heater chip has a plurality of heaters each having a length, width and thickness. The length multiplied by the width (heater area) is in a range from about 50 to about 500 micrometers squared while the thickness is in a range from about 500 to about 5000 or 6000 angstroms. The energy required to jet or emit a single drop of ink from the heater during use is in a range from about 0.007 to about 0.99 or 1.19 microjoules. The heater chip is formed as a plurality of thin film layers on a substrate. Energy ranges are taught for all heaters having an area from about 50 to about 4000 micrometers squared and thicknesses ranging from about 500 to about 16,000 angstroms. Printheads containing the heater chip and printers containing the printheads are also disclosed.
    Type: Grant
    Filed: July 15, 2003
    Date of Patent: December 28, 2004
    Assignee: LExmark International, Inc.
    Inventors: Byron Vencent Bell, Robert Wilson Cornell, Yimin Guan
  • Publication number: 20040196334
    Abstract: An improved ink jet printer ejector including a substantially hexagonal-donut shaped thin film resistor having a first end, a second end opposite the first end, a major axis having a first length, and a minor axis having a second length less than the first length. The major axis extends between the first end and the second end thereof. Electrical conductors are attached to the first end and to the second end of the resistor for activating the ink ejector on command from the ink jet printer. Hexagonl-donut shaped thin film resistors exhibit improved heating characteristics and lower power consumption than conventional heater resistors.
    Type: Application
    Filed: April 2, 2003
    Publication date: October 7, 2004
    Inventor: Robert Wilson Cornell
  • Publication number: 20040021718
    Abstract: A heater chip has a plurality of heaters each having a length, width and thickness. The length multiplied by the width (heater area) is in a range from about 50 to about 500 micrometers squared while the thickness is in a range from about 500 to about 5000 or 6000 angstroms. The energy required to jet or emit a single drop of ink from the heater during use is in a range from about 0.007 to about 0.99 or 1.19 microjoules. The heater chip is formed as a plurality of thin film layers on a substrate. Energy ranges are taught for all heaters having an area from about 50 to about 4000 micrometers squared and thicknesses ranging from about 500 to about 16,000 angstroms. Printheads containing the heater chip and printers containing the printheads are also disclosed.
    Type: Application
    Filed: July 15, 2003
    Publication date: February 5, 2004
    Inventors: Byron Vencent Bell, Robert Wilson Cornell, Yimin Guan
  • Publication number: 20040021740
    Abstract: A heater chip has a plurality of heaters each having a length, width and thickness. The length multiplied by the width (heater area) is in a range from about 50 to about 500 micrometers squared while the thickness is in a range from about 500 to about 5000 or 6000 angstroms. The energy required to jet or emit a single drop of ink from the heater during use is in a range from about 0.007 to about 0.99 or 1.19 microjoules. The heater chip is formed as a plurality of thin film layers on a substrate. Energy ranges are taught for all heaters having an area from about 50 to about 4000 micrometers squared and thicknesses ranging from about 500 to about 16,000 angstroms. Printheads containing the heater chip and printers containing the printheads are also disclosed.
    Type: Application
    Filed: July 15, 2003
    Publication date: February 5, 2004
    Inventors: Byron Vencent Bell, Robert Wilson Cornell, Yimin Guan
  • Patent number: 6676246
    Abstract: A heater chip structure having heating elements operable at an energy per unit volume of from about 2.9 GJ/m3 to about 4.0 GJ/m3, a pulse time of less than about 0.73 microseconds, and one or more protective layers having a total thickness of less than about 7200 angstroms.
    Type: Grant
    Filed: November 20, 2002
    Date of Patent: January 13, 2004
    Assignee: Lexmark International, Inc.
    Inventors: Frank Edward Anderson, Robert Wilson Cornell
  • Patent number: 6637866
    Abstract: The present invention is directed toward an improved heater chip for an ink jet printer. The heater chip has a diamond-like-carbon coating that functions as the cavitation and passivation layers of the heating elements on the heater chip. To improve the efficiency of the heater chip, the diamond-like-carbon coating is surrounded by a material that has a lower thermal conductivity than diamond. This surrounding layer limits thermal diffusion from the heating elements into the heater chip. A smoothing layer of tantalum is deposited over the diamond-like-carbon layer to insure that vaporization of the ink occurs at the ink's superheat limit. The diamond-like-carbon layer is preferably less than 8700 Angstroms in thickness such that less than 1 microjoule of energy is required to expel of ink droplet having a mass between 2-4 nanograms.
    Type: Grant
    Filed: June 7, 2002
    Date of Patent: October 28, 2003
    Assignee: Lexmark International, Inc.
    Inventors: Robert Wilson Cornell, George Keith Parish, James Harold Powers
  • Patent number: 6575563
    Abstract: An ink jet printer forms printed images by ejecting droplets of ink onto a print medium at a stable velocity. The printer includes an ink jet print head having nozzles through which the droplets of ink are ejected. The print head includes a heater chip having heating elements, each of which is associated with a corresponding one of the nozzles. Each heating element transfers heat into adjacent ink at a predetermined rate sufficient to maintain the stable velocity of the droplets of ink, where the predetermined rate of heat transfer is accomplished when a predetermined minimum power level is applied to the heating element. Each heating element includes a heater resistor and a protective layer having a protective layer thickness. Each heater resistor has a heater resistor area and a heater resistor thickness, and is operable to provide a predetermined minimum power density per unit area when the predetermined minimum power level is applied.
    Type: Grant
    Filed: August 5, 2002
    Date of Patent: June 10, 2003
    Assignee: Lexmark International, Inc.
    Inventor: Robert Wilson Cornell
  • Patent number: 6467864
    Abstract: A system provides an optimum energy pulse to a resistive heating element in an ink jet print head. The optimum energy pulse provides an optimal energy density at a surface of the heating element to cause optimal nucleation of ink adjacent the surface of the heating element. The system includes storing in memory values related to heating element dimensions, heating element electrical characteristics, and ink characteristics. Also stored in memory are expressions that provide mathematical relationships between the heating element dimensional values, the heating element electrical values, the ink characteristics, and the amplitude and duration of the optimum energy pulse. The system also includes retrieving from memory the stored values and expressions, and determining, based on the expressions, the amplitude and duration of the optimum energy pulse. The system further generates the optimum energy pulse based on the determined amplitude and duration, and provides the optimum energy pulse to the heating element.
    Type: Grant
    Filed: August 8, 2000
    Date of Patent: October 22, 2002
    Assignee: Lexmark International, Inc.
    Inventor: Robert Wilson Cornell
  • Patent number: 6296350
    Abstract: An ink jet printing apparatus is provided comprising a print cartridge including at least one resistive heating element in at least one ink-containing chamber having an orifice. The apparatus further includes a driver circuit, electrically coupled to the print cartridge, for applying to the resistive heating element warming and firing pulses separated by a delay period. The warming pulse causes the resistive heating element to warm a portion of the ink adjacent to the heating element and the firing pulse causes the resistive heating element to produce a vapor bubble in the chamber which causes a droplet of ink to be ejected from the chamber orifice.
    Type: Grant
    Filed: March 25, 1997
    Date of Patent: October 2, 2001
    Assignee: Lexmark International, Inc.
    Inventors: Robert Wilson Cornell, Bruce David Gibson
  • Patent number: 6234612
    Abstract: An ink jet printing apparatus is provided comprising first and second print cartridges. The first print cartridge includes at least one first resistive heating element in at least one first ink-containing chamber having a first orifice. The first heating element has a first surface area. The second print cartridge includes at least one second resistive heating element in at least one second ink-containing chamber having a second orifice. The second heating element has a second surface area which is less than the first surface area. The apparatus further comprises a driver circuit, electrically coupled to the first and second print cartridges, for selectively applying to one of the first and second heating elements via a common drive circuit a firing pulse. The firing pulse to the first heating element causing a vapor bubble to be produced in the first chamber such that a droplet of ink of a first size is ejected from the first chamber orifice.
    Type: Grant
    Filed: March 25, 1997
    Date of Patent: May 22, 2001
    Assignee: Lexmark International, Inc.
    Inventors: Robert Wilson Cornell, James Harold Powers
  • Patent number: 6213579
    Abstract: An apparatus and method is provided for compensating for the effects of thermally induced droplet size variations in ink-jet printers. The apparatus includes a temperature determination unit for determining the temperature of the print head, and a halftone adjustment unit configured to receive the print head temperature from the temperature determination unit and to receive image data in the form of nominal halftone values. The adjustment unit can increase or decrease the number of dots to be printed, and thereby compensate for droplet size variations, either by adjusting the nominal halftone values based upon the temperature or by adjusting a threshold array based upon the temperature. The temperature determination unit can predict the print head temperature by counting the number of dots to be printed by counting the binary halftone values fed to the swath memory.
    Type: Grant
    Filed: November 24, 1998
    Date of Patent: April 10, 2001
    Assignee: Lexmark International, Inc.
    Inventors: Robert Wilson Cornell, Scott Michael Heydinger, James H. Powers
  • Patent number: 6211970
    Abstract: A binary printer for printing halftone color images on a substrate so that the determination of whether to print a dot or to not print a dot of each color ink at each pixel location is based at least in part upon an estimated temperature of the print head. The temperature of the print head may be estimated based upon direct measurement of the ambient temperature and/or direct measurement of temperature of some portion of the print head. Alternatively, the temperature of the print head may be estimated by counting the number of dots fired by the print head.
    Type: Grant
    Filed: November 24, 1998
    Date of Patent: April 3, 2001
    Assignee: Lexmark International, Inc.
    Inventors: Robert Wilson Cornell, Scott Michael Heydinger, James H. Powers
  • Patent number: 6193349
    Abstract: An ink jet print cartridge is provided for use in an ink jet printer. The cartridge comprises a printhead including a heater chip. The printhead is adapted to generate ink droplets in response to the heater chip receiving energy pulses from a printer energy supply circuit. A peltier effect cooling cell is associated with the heater chip for cooling the heater chip. The cooling cell receives current from the printer energy supply circuit as a function of energy flow to the heater chip.
    Type: Grant
    Filed: June 18, 1997
    Date of Patent: February 27, 2001
    Assignee: Lexmark International, Inc.
    Inventors: Robert Wilson Cornell, William Paul Cook, Gary Allen Denton, James Harold Powers
  • Patent number: 6158843
    Abstract: A nozzle plate for a printhead of a thermal inkjet printer having a thickness sufficient to provide a plurality of nozzle holes above a plurality of firing chambers. Ink supply channels, for feeding ink to the firing chambers, are connected to an ink supply region and the nozzle plate has a plurality of projections sufficient to filter ink entering the supply channels from the supply region.
    Type: Grant
    Filed: March 28, 1997
    Date of Patent: December 12, 2000
    Assignee: Lexmark International, Inc.
    Inventors: Ashok Murthy, Steven Robert Komplin, Robert Wilson Cornell, James Harold Powers, Bruce David Gibson
  • Patent number: 6137502
    Abstract: An ink jet print head has first nozzles of a first diameter for ejecting droplets of ink having a first mass, and second nozzles of a second diameter for ejecting droplets of ink having a second mass. The first diameter is larger than the second diameter, and the first mass is larger than the second mass. First and second heater-switch pairs are connected in parallel on a substrate of the print head. The first heater-switch pairs include first heaters adjacent corresponding first nozzles, and the second heater-switch pairs include second heaters adjacent corresponding second nozzles. The first and second heaters are composed of electrically resistive material occupying first and second heater areas on the substrate. The first heater-switch pairs also include first switching devices connected in series with the first heaters, with each first switching device developing a first switching device voltage drop as a first electrical current flows through.
    Type: Grant
    Filed: August 27, 1999
    Date of Patent: October 24, 2000
    Assignee: Lexmark International, Inc.
    Inventors: Frank Edward Anderson, John Philip Bolash, Robert Wilson Cornell, George Keith Parish
  • Patent number: 6132030
    Abstract: The invention described herein relates to a method for printing with a thermal ink jet printer. A thermal ink jet print head containing a plurality of resistance heaters is provided. To each resistance heater there is an electrical current path, and each resistance heater also has a surface for heating the ink adjacent the surface. By providing an electrical current to the heaters to heat the ink such that a heater power density of at least about two gigawatts per square meter is obtained, print quality may be dramatically improved.
    Type: Grant
    Filed: April 19, 1996
    Date of Patent: October 17, 2000
    Assignee: Lexmark International, Inc.
    Inventor: Robert Wilson Cornell
  • Patent number: 6109719
    Abstract: The invention described in the specification relates to an apparatus and method for cooling a printhead containing multiple semiconductor substrates. The substrates which contain a plurality of energy imparting devices for energizing ink are attached to a metal substrate carrier for providing efficient heat transfer from the substrates. A temperature sensing device is attached to the carrier for measuring a temperature of the substrate carrier during a printing operation and for generating an input signal to a controller. The controller, in turn, sends an output signal to the printhead to selectively energize one or more of the energy imparting devices on each substrate in response to the input signal and a thermal expansion value based on the temperature of the heat transfer member. Because the timing of energization of the energy imparting devices is controlled in response to the carrier temperature and its expansion characteristics, more cost effective materials for the carrier can be used.
    Type: Grant
    Filed: June 3, 1998
    Date of Patent: August 29, 2000
    Assignee: Lexmark International, Inc.
    Inventor: Robert Wilson Cornell