Patents by Inventor David T. Shadwick

David T. Shadwick 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: 7245378
    Abstract: Methods for measuring laser light transmissivity of a specific position in a work piece prior to the work piece undergoing laser welding at the specific position with a laser beam having a specific welding wavelength. To obtain a baseline measurement reading, a laser light source projects a laser beam at the welding wavelength directly into a detector. Thereafter, the work piece becomes suspended between the laser light source and detector whereby an output of the detector now corresponds to a work piece measurement reading. Differences between the two readings reveal whether the work piece will yield a satisfactory weld at the specific position when later welded by a laser beam at the welding wavelength. Preferred work pieces include inkjet printhead lids and bodies.
    Type: Grant
    Filed: September 16, 2005
    Date of Patent: July 17, 2007
    Assignee: Lexmark International, Inc.
    Inventors: Kin-Ming Kwan, Jonathan H. Laurer, David T. Shadwick, Audrey D. Rodgers
  • Patent number: 6998008
    Abstract: An apparatus for a laser transmission welding process for attaching a synthetic filter material to a filter tower frame in an ink jet printer cartridge. The apparatus includes a laser beam source and a filter clamping fixture containing a base, slide rods attached on first ends thereof to the base, an optics support plate attached to second ends of the slide rods, a movable platform for holding an ink cartridge slidably disposed on the slide rods between the base and the optics support plate, a platform moving device for translating the platform to and from a laser welding position, a laser beam transparent plate suspended by support legs from the optics support plate to a position between the movable platform and the optics support plate. The apparatus greatly improves synthetic filter attachment to a filter tower frame in an ink cartridge.
    Type: Grant
    Filed: July 15, 2003
    Date of Patent: February 14, 2006
    Assignee: Lexmark International, Inc.
    Inventors: Kin Ming Kwan, David T. Shadwick, Jeanne M. Saldanha, Paul T. Spivey, Jon B. Whitney, Julie A. Gordon Whitney
  • Patent number: 6980296
    Abstract: Methods for measuring laser light transmissivity of a specific position in a work piece prior to the work piece undergoing laser welding at the specific position with a laser beam having a specific welding wavelength. To obtain a baseline measurement reading, a laser light source projects a laser beam at the welding wavelength directly into a detector. Thereafter, the work piece becomes suspended between the laser light source and detector whereby an output of the detector now corresponds to a work piece measurement reading. Differences between the two readings reveal whether the work piece will yield a satisfactory weld at the specific position when later welded by a laser beam at the welding wavelength. Preferred work pieces include inkjet printhead lids and bodies.
    Type: Grant
    Filed: March 30, 2005
    Date of Patent: December 27, 2005
    Assignee: Lexmark International, Inc.
    Inventors: Kin-Ming Kwan, Jonathan H. Laurer, David T. Shadwick, Audrey D. Rodgers
  • Patent number: 6796644
    Abstract: A regulator adapted to regulate the throughput of an ink between an ink source and a print head includes: (a) a pressurized chamber including an ink inlet in fluid communication with and ink source, an ink outlet in fluid communication with a print head, and at least one flexible wall; and (b) a lever including a flexible arm extending along a portion of the flexible wall and an opposing arm operatively coupled to a seal biased to close the ink inlet when the lever is in a first position and to open the ink inlet to allow fluid communication between the ink inlet and the pressurized chamber when the lever is pivoted to a second position; where a lower pressure differential across the flexible wall causes the flexible wall to actuate the flexible arm, pivoting the lever to the first position (inlet closed), where a higher pressure differential across the flexible wall causes the flexible wall to actuate the flexible arm to pivot the lever to the second position (inlet open), and where a pressure change from th
    Type: Grant
    Filed: June 18, 2003
    Date of Patent: September 28, 2004
    Assignee: Lexmark International, Inc.
    Inventors: James D. Anderson, Jr., Gerald F. Davis, John R. Fowler, David E. Greer, Trevor D. Gray, Timothy L. Howard, Steven R. Komplin, Matthew J. Russell, David T. Shadwick
  • Publication number: 20040150688
    Abstract: Methods for measuring laser light transmissivity of a specific position in a work piece prior to the work piece undergoing laser welding at the specific position with a laser beam having a specific welding wavelength. To obtain a baseline measurement reading, a laser light source projects a laser beam at the welding wavelength directly into a detector. Thereafter, the work piece becomes suspended between the laser light source and detector whereby an output of the detector now corresponds to a work piece measurement reading. Differences between the two readings reveal whether the work piece will yield a satisfactory weld at the specific position when later welded by a laser beam at the welding wavelength. Preferred work pieces include inkjet printhead lids and bodies.
    Type: Application
    Filed: January 30, 2003
    Publication date: August 5, 2004
    Inventors: Kin-Ming Kwan, Jonathan H. Laurer, David T. Shadwick, Audrey D. Rodgers
  • Patent number: 4840503
    Abstract: A fabric ribbon (13) is stuffed in a cartridge chamber (11). Two pinch rollers (35 and 39) are driven by a third roller (29). The direction for forces from the pinch rollers is toward a wall portion (9a), which is near an opening having a dam (ridge 67) which leads to chamber (74) have an exit slot (71) located near the wall portion (9a). The drive roller (29) is positioned to be located where the drive roller of an existing cartridge was located, making this cartridge interchangeable with a cartridge for a spool-to-spool ribbon.
    Type: Grant
    Filed: March 31, 1988
    Date of Patent: June 20, 1989
    Assignee: International Business Machine Corporation
    Inventors: Sheldon D. Roberts, Louann B. Samuels, David T. Shadwick
  • Patent number: 4523868
    Abstract: The feeding of typewriter ribbons is improved by utilizing a cartridge carried driving element engaging the periphery of a translatable take-up spool where the driving element is driven by an interface connection with a driving member connected either directly or through a gear reduction train to a stepper motor. The simplified ribbon feed mechanism provides control over the increment of feed electronically as well as each ribbon cartridge carrying the appropriate gear reductions, if necessary, for different types of ribbons.
    Type: Grant
    Filed: July 18, 1983
    Date of Patent: June 18, 1985
    Assignee: International Business Machines Corporation
    Inventor: David T. Shadwick
  • Patent number: D309323
    Type: Grant
    Filed: February 6, 1989
    Date of Patent: July 17, 1990
    Assignee: International Business Machines Corporation
    Inventors: James A. Craft, William D. Freeman, James J. Molloy, David T. Shadwick, Thomas G. Twardeck, James P. Wang