Patents by Inventor Robert F. Dunham

Robert F. Dunham 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: 6863730
    Abstract: An apparatus including: a movement device that moves an object to be coated; a slot die coater equipped with a position sensor mounted on at least one end of the slot die coater and which slot die coater controllably dispenses coating material onto the moving object; and at least one servor motor-controller system in electrical contact with the position sensor, wherein the position sensor senses the position of the slot die coater relative to the object and wherein the at least one servor motor-controller system adjusts the position of the slot die coater relative to the object if the position of the slot die coater relative to the moving substrate deviates from a set of predetermined coordinates.
    Type: Grant
    Filed: February 19, 2003
    Date of Patent: March 8, 2005
    Assignee: Xerox Corporation
    Inventors: Thomas A. Trabold, Robert F. Dunham, John M. Hammond
  • Patent number: 6706315
    Abstract: A process comprising: providing a moving substrate; applying at least one coating layer wherein the at least one coating Is a photoconductive material, an electrically insulating material, a hole transport material, an anti-curl material, or an adhesive material onto the moving substrate with a slot die coater equipped with at least one position sensor mounted on at least one end of the slot die coater, and for example, applying from one to about five coating layers on the substrate; sensing the position of the slot die coater relative to the moving substrate with at least one position sensor; and, when the position of the slot die coater relative to the moving substrate deviates from a set of predetermined coordinates, iteratively adjusting the position of the die coater relative to the surface of the substrate to return to the set of predetermined coordinates.
    Type: Grant
    Filed: September 17, 2001
    Date of Patent: March 16, 2004
    Assignee: Xerox Corporation
    Inventors: Thomas A. Trabold, Robert F. Dunham, John M. Hammond
  • Publication number: 20030157243
    Abstract: An apparatus including: a movement device that moves an object to be coated; a slot die coater equipped with a position sensor mounted on at least one end of the slot die coater and which slot die coater controllably dispenses coating material onto the moving object; and at least one servor motor-controller system in electrical contact with the position sensor, wherein the position sensor senses the position of the slot die coater relative to the object and wherein the at least one servor motor-controller system adjusts the position of the slot die coater relative to the object if the position of the slot die coater relative to the moving substrate deviates from a set of predetermined coordinates.
    Type: Application
    Filed: February 19, 2003
    Publication date: August 21, 2003
    Applicant: Xerox Corporation
    Inventors: Thomas A. Trabold, Robert F. Dunham, John M. Hammond
  • Publication number: 20030054107
    Abstract: An apparatus including: a movement device that moves an object to be coated; a slot die coater equipped with a position sensor mounted on at least one end of the slot die coater and which slot die coater controllably dispenses coating material onto the moving object; and at least one servor motor-controller system in electrical contact with the position sensor, wherein the position sensor senses the position of the slot die coater relative to the object and wherein the at least one servor motor-controller system adjusts the position of the slot die coater relative to the object if the position of the slot die coater relative to the moving substrate deviates from a set of predetermined coordinates.
    Type: Application
    Filed: September 17, 2001
    Publication date: March 20, 2003
    Applicant: Xerox Corporation
    Inventors: Thomas A. Trabold, Robert F. Dunham, John M. Hammond
  • Patent number: 6270850
    Abstract: A method for improving the quality of a dip coated layer that is deposited by flowing a solution along a substrate in a gap between the substrate and a wall, including: (a) determining a yield stress, a viscosity, a density, and a surface tension of the solution, and selecting a wet thickness of the coated layer; (b) determining a coating speed based on the determined viscosity, the determined density, the determined surface tension of the solution, and the selected wet layer thickness; and (c) selecting a distance for the gap and calculating the shear stress of the solution in the gap based on the gap distance, wherein the shear stress is greater than the yield stress.
    Type: Grant
    Filed: June 10, 1999
    Date of Patent: August 7, 2001
    Assignee: Xerox Corporation
    Inventors: Jian Cai, Huoy-Jen Yuh, Merlin E. Scharfe, Robert F. Dunham
  • Patent number: 6245475
    Abstract: A method of forming one or more polymer containing layers on a substrate using ink jet nozzles. The method is particularly suited to forming one or more polymer containing layers of a photoreceptor. The polymer containing layers may be formed by moving a substrate, in particular a cylindrical substrate, past the ink jet nozzles, by moving the ink jet nozzles over the substrate, or both. The ink jet nozzles are capable of being independently controlled in order to permit precise location of the coating on the substrate.
    Type: Grant
    Filed: December 16, 1999
    Date of Patent: June 12, 2001
    Assignee: Xerox Corporation
    Inventors: Merlin E. Scharfe, John M. Hammond, Robert F. Dunham, Jian Cai, Kenny Tuan Dinh, Roger T. Janezic
  • Patent number: 6214513
    Abstract: A coating process for the fabrication of organic photoreceptors employs an electrically conductive single slot die biased to allow an electric field between the die and the ground plane on the photoreceptor substrate. The homogenous coating dispersion is fed through the die at a predetermined gap and rate to control coating thickness at the same time that an electric field is applied. The formulation, rheology, particle mobility, coating speed, electric field and the like are controlled so that the photogenerator particles migrate to the substrate in the dwell time defined by the coating die region.
    Type: Grant
    Filed: November 24, 1999
    Date of Patent: April 10, 2001
    Assignee: Xerox Corporation
    Inventors: Jian Cai, Robert F. Dunham, Merle Emil Scharfe, Ian D. Morrison
  • Patent number: 6195443
    Abstract: A manufacturing system including: (a) a vessel for holding a liquid; (b) a first member and a second member, each having a flat surface, wherein the flat surface of the first member faces and is spaced from the flat surface of the second member, thereby defining a gap region between the two flat surfaces, wherein a section of the first member is transparent through the thickness of the first member; (c) a liquid delivery system connected to the vessel and the gap region which delivers the liquid to the gap region and the liquid flows in the gap region in view of the transparent section of the first member; (d) a camera positioned to view through the transparent section of the first member; (e) image processing means coupled to the camera for determining the homogeneity of the liquid in the gap region; and (f) liquid dispensing equipment connected to the liquid delivery system.
    Type: Grant
    Filed: May 15, 1998
    Date of Patent: February 27, 2001
    Assignee: Xerox Corporation
    Inventors: John M. Hammond, Jian Cai, Kent J. Evans, John G. Matta, Robert F. Dunham, Mario Errico, Julie A. Cady, Mark C. Petropoulos, Stanley J. Pietrzykowski, Jr., Mark S. Thomas
  • Patent number: 6048658
    Abstract: A process for fabricating electrophotographic imaging members comprising providing a substrate with an exposed surface, simultaneously applying, from a coating die, two wet coatings to the surface, the wet coatings comprising a first coating in contact with the surface, the first coating comprising photoconductive particles dispersed in a solution of a film forming binder and a predetermined amount of solvent for the binder and a second coating in contact with the first coating, the second coating comprising a solution of a charge transporting small molecule and a film forming binder dissolved in a predetermined amount of solvent for the transport molecule and the binder, drying the two wet coatings to remove substantially all of the solvents to form a dry first coating having a thickness between about 0.
    Type: Grant
    Filed: September 29, 1999
    Date of Patent: April 11, 2000
    Assignee: Xerox Corporation
    Inventors: Kent J. Evans, Robert F. Dunham, Alfred H. Willnow
  • Patent number: 5394622
    Abstract: A dryer with zone temperature controls for drying thick polymer-solvent layers on a substrate. The dryer is formed with several heating elements located in an air duct. The cool air is heated a specific amount as it passes each heating element. The heated air is then applied to the polymer-solvent solution on the substrate in a continuous fashion so that the polymer-solvent solution slowly heats up as it passes through the drying apparatus. The preferred design is to ensure a zone residence time of less than 10 seconds and a web heating rate of 10.degree. F./second or less. Most preferred design is a zone residence time less than 5 seconds and a heating rate less that 5.degree. F./second. The dryer is designed to have a continuous temperature gradient, especially in the critical later stages of drying when the solvent content of the film is less than 20%.
    Type: Grant
    Filed: June 15, 1993
    Date of Patent: March 7, 1995
    Assignee: Xerox Corporation
    Inventors: Kent J. Evans, Warren R. Smith, Robert F. Dunham, Timothy J. Leenhouts, Barbara D. Ceglinski, Richard A. Cairncross
  • Patent number: 5273583
    Abstract: Apparatus for the continuous coating of charge transport solutions onto a substrate to form an electrophotographic imaging member, including a pump to a flow of a first highly doped charge transport solution and a pump to a flow of a second undoped or lowly doped charge transport solution at predetermined rates to a common junction at which the flows intermix into a common flow upon contacting each other; piping connecting the pumping means to the common junction; and mixing device associated with the junction for continuously mixing the common flow during its movement through the mixing device, the mixing device having a short spiral flow path of less than about 200 cm for the solutions sufficient to substantially complete mix the common flow during its movement through the mixing means.
    Type: Grant
    Filed: May 1, 1992
    Date of Patent: December 28, 1993
    Assignee: Xerox Corporation
    Inventors: Edouard E. Langlois, Kathryn T. Kehoe, Warren R. Smith, Mark Muscato, Barbara D. Ceglinski, Alan C. Kirchoff, Robert F. Dunham, Michael D. Stair
  • Patent number: 5149612
    Abstract: Processes and apparatus for fabricating an electrophotographic imaging member in which a web coated with a charge generation layer is coated with a charge transport layer comprising a dopant, the improvement comprising detecting the change in dopant concentration required, determining the amount of highly doped charge transport composition and amount of undoped or lowly doped charge transport composition required to achieve the change in dopant concentration, feeding the determined amounts of highly doped charge transport composition and undoped or lowly doped charge transport composition into a mixing zone, rapidly mixing the amounts of highly doped charge transport composition and undoped or lowly doped charge transport composition to form a uniformly doped charge transport composition, and applying the uniformly doped charge transport composition to the charge generation layer.
    Type: Grant
    Filed: July 2, 1990
    Date of Patent: September 22, 1992
    Assignee: Xerox Corporation
    Inventors: Edouard E. Langlois, Kathryn T. Kehoe, Warren R. Smith, Mark Muscato, Barbara D. Ceglinski, Alan C. Kirchoff, Robert F. Dunham, Michael D. Stair