Patents by Inventor David Vejtasa

David Vejtasa 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: 8824931
    Abstract: Liquid marking agent development assemblies and liquid marking agent hard imaging methods are described. According to one aspect, a liquid marking agent development assembly includes a developer member comprising an outer surface and a charging assembly adjacent to the outer surface of the developer member, and wherein the charging assembly comprises at least one roller member configured to provide substantially an entirety of an electrical field relative to the developer member which electrical field is used to direct a plurality of ink particles of a liquid marking agent to the outer surface of the developer member and which ink particles upon the outer surface of the developer member are used to develop latent images upon an imaging member.
    Type: Grant
    Filed: May 29, 2009
    Date of Patent: September 2, 2014
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Eric G. Nelson, David Sabo, David Vejtasa
  • Patent number: 8626038
    Abstract: A developer unit usable with a liquid electrophotographic printing apparatus having a photosensitive drum includes a developer roller configured to receive ink, and to selectively engage and rotatably transfer the ink to the photosensitive drum, the developer roller configured to switch between a contact mode when the developer roller is rotating and a non-contact mode when the developer roller is not rotating, a squeegee roller selectively in contact with the developer roller, the squeegee roller configured to at least condense the received ink on the developer roller in the contact mode, and configured to be apart from the developer roller in the non-contact mode, and a cleaner roller selectively in contact with the developer roller, the cleaner roller configured to remove remaining ink from the developer roller not transferred to the photosensitive drum in the contact mode, and to be apart from the developer roller in the non-contact mode, wherein at least one of the squeegee roller, the cleaner roller and
    Type: Grant
    Filed: June 8, 2009
    Date of Patent: January 7, 2014
    Assignee: Hewlett-Packard Development Company, L. P.
    Inventors: Eric Nelson, David Vejtasa, Alexander Karp, Christopher S Tanner
  • Patent number: 8322824
    Abstract: A method and apparatus for printing fluid on a substrate is provided. The method includes providing drops of the fluid on the substrate and spreading the drops of fluid to increase the surface area covered by those drops. The apparatus includes a printer having a print head for printing drops of fluid on the substrate and a spreader for spreading the fluid drops on the substrate.
    Type: Grant
    Filed: April 30, 2007
    Date of Patent: December 4, 2012
    Assignee: Hewlett-Packard Development Company, L. P.
    Inventors: Eyal Peleg, Benji Ruhm, Thomas M Sabo, Clayton L Holstun, Ronald A Askeland, Ran Vilk, David Vejtasa, Omer Markovsky
  • Publication number: 20120148311
    Abstract: Liquid marking agent development assemblies and liquid marking agent hard imaging methods are described. According to one aspect, a liquid marking agent development assembly includes a developer member comprising an outer surface and a charging assembly adjacent to the outer surface of the developer member, and wherein the charging assembly comprises at least one roller member configured to provide substantially an entirety of an electrical field relative to the developer member which electrical field is used to direct a plurality of ink particles of a liquid marking agent to the outer surface of the developer member and which ink particles upon the outer surface of the developer member are used to develop latent images upon an imaging member.
    Type: Application
    Filed: May 29, 2009
    Publication date: June 14, 2012
    Applicant: Hewlett-Packard Development Company, L.P.
    Inventors: Eric G. Nelson, David Sabo, David Vejtasa
  • Publication number: 20120027468
    Abstract: A developer unit usable with a liquid electrophotographic printing apparatus having a photosensitive drum includes a developer roller configured to receive ink, and to selectively engage and rotatably transfer the ink to the photosensitive drum, the developer roller configured to switch between a contact mode when the developer roller is rotating and a non-contact mode when the developer roller is not rotating, a squeegee roller selectively in contact with the developer roller, the squeegee roller configured to at least condense the received ink on the developer roller in the contact mode, and configured to be apart from the developer roller in the non-contact mode, and a cleaner roller selectively in contact with the developer roller, the cleaner roller configured to remove remaining ink from the developer roller not transferred to the photosensitive drum in the contact mode, and to be apart from the developer roller in the non-contact mode, wherein at least one of the squeegee roller, the cleaner roller and
    Type: Application
    Filed: June 8, 2009
    Publication date: February 2, 2012
    Inventors: Eric Nelson, David Vejtasa, Alexander Karp, Christopher S. Tanner
  • Publication number: 20050095035
    Abstract: Aspects of the invention relate to hard imaging device charging systems, liquid electrophotography charging systems, hard imaging apparatuses, and hard imaging device electrophotography charging methods. In one embodiment, a hard imaging device charging system is described. The charging system may include a first charging device configured to charge a respective first region of a cylindrical image bearing member used to form latent images during hard imaging operations of the hard imaging device. The charging system may also include a second charging device configured to charge a respective second region of the cylindrical image bearing member used to form latent images during hard imaging operations of the hard imaging device. The first and second regions may have different radii from a central axis of the cylindrical image bearing member.
    Type: Application
    Filed: October 31, 2003
    Publication date: May 5, 2005
    Inventors: David Vejtasa, Omer Gila, Gregory Ellis, Thomas Camis, Peter Gysling
  • Publication number: 20050095036
    Abstract: Aspects of the invention relate to hard imaging apparatus charging devices, imaging assemblies, imaging assemblies charging methods, and hard imaging device image bearing member charging methods. In one aspect, a hard imaging apparatus charging device is disclosed. The charging device includes first and second end members, and an intermediate member connecting the first and second end members. The intermediate member may have a length corresponding to an imaging area of the image bearing member of the hard imaging apparatus. The intermediate member may be configured to charge the imaging area used to form latent images on the image bearing member during hard imaging operations of the hard imaging apparatus. The first and second end members of the charging device may be configured to maintain a predetermined spaced charging clearance between the intermediate member and the imaging area of the image bearing member.
    Type: Application
    Filed: October 31, 2003
    Publication date: May 5, 2005
    Inventors: Omer Gila, David Vejtasa, Michael Lee, Thomas Camis, Peter Gysling