Patents by Inventor Chuong C. Ta

Chuong C. Ta 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: 5880757
    Abstract: A swath type printer including a print carriage supported printhead and a printhead positioning mechanism for adjusting the position of the printhead relative to the media axis at the end of each scan of the carriage along a carriage axis, such that dots printed by printing elements of the printhead in a sequence of a first scan and a second scan of the print carriage are interleaved along the media axis and are separated along the media axis by one-half of the predetermined printing element dot pitch.
    Type: Grant
    Filed: September 10, 1996
    Date of Patent: March 9, 1999
    Assignee: Hewlett-Packard Company
    Inventor: Chuong C. Ta
  • Patent number: 5861899
    Abstract: Greater throughput is possible by using wider print swaths in each traverse across printing media. Multiple print cartridges are mounted to be offset from each other in the media scan direction (X-axis). The amount of offset is adjustably varied by selective on/off control of individual printing elements as well as by relative mechanical movement of the print cartridges.
    Type: Grant
    Filed: November 13, 1995
    Date of Patent: January 19, 1999
    Assignee: Hewlett-Packard Company
    Inventors: Michael A. Nguyen, Lowell J. Stewart, Daniel S. Kline, Robert A. Boeller, Chuong C. Ta, Robert D. Haselby
  • Patent number: 5691754
    Abstract: An ink jet printer that including a movable print carriage, an ink jet printhead cartridge removably supported by the movable print carriage, a stationary ink reservoir located remotely from the ink jet printhead cartridge, a movable ink conveying coupler fluidically coupled to the stationary ink reservoir, and a rigid ink conveying tube connected between the movable ink conveying coupler and the ink jet printhead cartridge, wherein the movable ink conveying coupler moves relative to the stationary ink reservoir as the movable carriage moves along a carriage axis. A ink pump can be driven by the reciprocating motion of the movable ink conveying coupler, and another rigid ink conveying tube be provided to achieve ink recirculation for printhead cooling.
    Type: Grant
    Filed: August 19, 1996
    Date of Patent: November 25, 1997
    Assignee: Hewlett-Packard Company
    Inventor: Chuong C. Ta
  • Patent number: 5537227
    Abstract: A facsimile machine containing an improved paper separator system is described where, instead of a symmetrical, cylindrical paper-feed roller, an asymmetrical feed roller (or stripper roller) is used to separate a bottommost sheet from a stack of sheets. Eccentric portions of the feed roller are located at both ends of the roller, and the middle portion of the roller is cylindrical. Paper-feed springs oppose the eccentric portions of the feed roller, while a centrally located separator pad opposes the cylindrical middle portion of the feed roller. The extended radius at the apogee of the eccentric portions allows the eccentric portions to effectively reach out and grab the bottommost sheet even if the stack of sheets were only initially lightly contacting the roller. The eccentric portions of the feed roller also provide surges in the frictional force urging the bottommost sheets toward the separator pad.
    Type: Grant
    Filed: October 14, 1994
    Date of Patent: July 16, 1996
    Assignee: Hewlett-Packard Company
    Inventors: Morad M. Samii, Chuong C. Ta
  • Patent number: 5488397
    Abstract: Greater throughput is possible by using wider print swaths in each traverse across printing media. Multiple print cartridges are mounted to be offset from each other in the media scan direction (X-axis). The amount of offset is adjustably varied by selective on/off control of individual printing elements as well as by relative mechanical movement of the print cartridges.
    Type: Grant
    Filed: November 4, 1991
    Date of Patent: January 30, 1996
    Assignee: Hewlett-Packard Company
    Inventors: Michael A. Nguyen, Lowell J. Stewart, Daniel S. Kline, Robert A. Boeller, Chuong C. Ta, Robert D. Haselby
  • Patent number: 5034758
    Abstract: A dust shield for preventing paper dust from fouling a printer and printhead mechanism is disclosed. In a sprocket-wheel paper drive printer, the sprockets are at least partially encased as they enter and exit the holes in the paper. Paper particles are trapped and then channelled away from mechanisms, such as a thermal ink jet cartridge printhead, whose operation may be detrimentally affected by such dust.
    Type: Grant
    Filed: October 17, 1989
    Date of Patent: July 23, 1991
    Assignee: Hewlett-Packard Company
    Inventors: Anthony W. Ebersole, Robert W. Beauchamp, Chuong C. Ta
  • Patent number: 4786803
    Abstract: The single channel encoder comprises a transparent scale in which the scale divisions are defined by transverse opaque lines having a width greater than the width between the opaque lines. An emitter holder and a detector holder snap together, clamping an aperture plate there between. The aperture plate has a slit therein which is disposed in the optical path between the emitter and the detector. Projections functioning as scale supports on the opposite sides of the emitter holder and the detector holder are disposed in longitudinally spaced positions and define a gap therebetween for engaging the outside edges of the encoder scale outside of the opaque transverse lines to precisely position the scale in the optical path for maintaining a constant gap between the encoder scale and the aperture plate.
    Type: Grant
    Filed: June 1, 1987
    Date of Patent: November 22, 1988
    Assignee: Hewlett-Packard Company
    Inventors: Mark W. Majette, Hatem E. Mostafa, Chuong C. Ta
  • Patent number: 4755836
    Abstract: A printhead cartridge and carriage assembly (10) for use with ink-jet printers is disclosed. The assembly is provided with means (56) for ensuring that an ink-jet cartridge (20) is securely locked in place in a cartridge carrier (12), means (78, 78a, 80, 80a, 82, 82a) for ensuring that cartridge is registered in a given, fixed, repeatable position each time, means (128) for ensuring that the cartridge is spaced from the printing medium (40) a minimum, fixed distance, means (100) on the carriage for maintaining this fixed distance, and interconnect means (84) for connecting a printhead assembly (34) on the cartridge with a microprocessor for controlling the pattern of ink drop ejection. The assembly further includes a preloader assembly (106) for preventing backward rotational pivoting of the carriage about a slider rod (44) associated with a platen (46) of the printer and for urging the carriage toward the medium on the platen.
    Type: Grant
    Filed: May 5, 1987
    Date of Patent: July 5, 1988
    Assignee: Hewlett-Packard Company
    Inventors: Chuong C. Ta, Todd L. Russell, Anthony W. Ebersole
  • Patent number: D581456
    Type: Grant
    Filed: November 15, 2007
    Date of Patent: November 25, 2008
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Christopher L. Whittall, Todd Haseyama, Catherine Moana Huneke Harriss, Chuong C. Ta, Allen Zadeh, Gina L Reimann, Dario Giovanni Miticocchio, Anthony A. Di Bitonto