Patents by Inventor Stephen T. Chai

Stephen T. Chai 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: 5983064
    Abstract: Simulated photographic prints are created using xerographic imaging. A transparent carrier having a xerographically formed mirror image fused thereto is bonded to a plastic substrate through the use of heat and pressure. The transparent carrier and the plastic substrate passed through a heat pressure fuser to form the finished print.
    Type: Grant
    Filed: July 21, 1993
    Date of Patent: November 9, 1999
    Assignee: Xerox Corporation
    Inventors: Leland D. Green, Thomas A. Hanna, Stephen T. Chai
  • Patent number: 5978630
    Abstract: A system for removing residual contaminants from an image conditioning apparatus that removes excess liquid from a developed image made up of toner particles immersed in a liquid carrier medium on an image bearing member. The system includes a vacuum blotting device that contacts the liquid developed image and absorbs a portion of the liquid carrier and residual contaminants remain thereon. A contact member adapted to be shifted from a non-operative position spaced from the vacuum blotting device, to an operative position in contact with the vacuum blotting device operates to transfer the contaminants therefrom. A scraper removes the transferred contaminants from the contact member. The contact member is pivotally mounted about the pivot point to effect shifting of the contact member between the non-operative and the operative position.
    Type: Grant
    Filed: January 8, 1998
    Date of Patent: November 2, 1999
    Assignee: Xerox Corporation
    Inventors: Shu Chang, John F. Knapp, Lawrence Floyd, Jr., Stephen T. Chai, Robert E. Trott
  • Patent number: 5708936
    Abstract: An apparatus for developing an electrostatic latent image with liquid developing material. The apparatus includes a liquid developing material coating flow applicator for applying a substantially uniform coating of liquid developing material to a moving surface, wherein a housing, situated proximate to the moving surface, includes a fluid transport channel having a relatively narrow-width elongated outlet port for delivering a flow of liquid developing material to the moving surface, and an air flow channel having an elongated inlet aperture located adjacent the moving surface and immediately upstream from said outlet port for applying vacuum pressure to the flow of liquid developing material for varying the profile of the coating flow to provide variation of flow stability as well as thickness. A discussion of the effects of variations in the outlet port geometry, in particular, increasing the dimension between the downstream wall and the surface to be coated, has also been provided.
    Type: Grant
    Filed: September 3, 1996
    Date of Patent: January 13, 1998
    Assignee: Xerox Corporation
    Inventors: Fong-Jen Wang, Gerald A. Domoto, Paul W. Morehouse Jr., John F. Knapp, Thomas A. Hanna, Stephen T. Chai, Joseph F. Lacchia
  • Patent number: 5481341
    Abstract: A roller for controlling the application of carrier liquid to an image bearing member in an electrostatographic reproduction apparatus having a rigid porous electroconductive supportive core, a conformable microporous covering provided around the core, and a pressure controller. The pressure controller is located to provide a positive or negative pressure within the porous core and across a cross section of the core and covering.
    Type: Grant
    Filed: August 18, 1993
    Date of Patent: January 2, 1996
    Assignee: Xerox Corporation
    Inventors: Donald S. Sypula, Santokh S. Badesha, Shu Chang, John F. Knapp, Robert E. Trott, Stephen T. Chai, Henry R. Till, Joseph Mammino
  • Patent number: 5467171
    Abstract: An apparatus for steering a moving web, particularly in an electrophotographic printing machine of the type having an endless photoreceptor belt supported by a plurality of rolls and arranged to move in a predetermined path through a plurality of processing stations disposed therealong the web being of the type which is supported by a plurality of rolls. A web steering roll for supporting the web being adapted for rotational movement about a first axis and tilting movement about a second axis transverse to the first axis is used.
    Type: Grant
    Filed: September 17, 1993
    Date of Patent: November 14, 1995
    Assignee: Xerox Corporation
    Inventors: Vittorio Castelli, Stephen T. Chai
  • Patent number: 5387962
    Abstract: An apparatus for guiding a moving web, particularly in an electrophotographic printing machine of the type having an endless photoreceptor belt supported by a plurality of rolls and arranged to move in a predetermined path through a plurality of processing stations disposed therealong the web being of the type which is supported by a plurality of rolls. A roll for supporting the web and in frictional contact therewith is adapted for rotational movement about a first axis. A roll support in the form of a dead shaft allows the roll laterally move to pivot about a second axis in a direction substantially normal to the predetermined path direction. This is accomplished by supporting the dead shaft on a V-groove roller which rides in a track substantially along the arc of rotation normal to the predetermined path direction.
    Type: Grant
    Filed: December 13, 1993
    Date of Patent: February 7, 1995
    Assignee: Xerox Corporation
    Inventors: Vittorio Castelli, Harold Brown, Stephen T. Chai
  • Patent number: 5200782
    Abstract: A belt receptor module for a color printer isolates disturbances such as impulsive and high-frequency force disturbances caused by entrance of a recording medium into a transfer nip of a transfer station. The belt receptor module includes a belt receptor positioned about a plurality of spaced rollers. A transfer station is located adjacent an area of the belt receptor. A tension roller is located adjacent the belt receptor on either side of the transfer station. The tension rollers each articulate about an appropriate axis to enable the belt receptor to enter a subsequent roller at angle of approximately 90.degree. to its axis without generating lateral forces. Each tension roller is movable along a different line to create a tension level therein, each tension level being different from the other tension level.
    Type: Grant
    Filed: November 1, 1991
    Date of Patent: April 6, 1993
    Assignee: Xerox Corporation
    Inventors: Vittorio R. Castelli, Stephen T. Chai
  • Patent number: 5157443
    Abstract: A method and apparatus is disclosed for an improved liquid development system for a high speed reproducing machine having a movable image retention belt. The liquid development system comprising a moving belt applicator mounted on a drive assembly containing at least one drive roll and a low lateral force roll with a position guide. The belt applicator is located in alignment with the image retention belt and spaced therefrom to form a development zone having a uniform gap with an extended length. The applicator drive roll and a low lateral force roll are positoned to transport the belt applicator in the same or opposite direction as the image retention belt, but at a much faster speed to facilitate an evenly distributed flow of liquid developer and to avoid depletion of toner particles from the liquid developer moved through the development zone.
    Type: Grant
    Filed: September 23, 1991
    Date of Patent: October 20, 1992
    Assignee: Xerox Corporation
    Inventors: Harold M. Anderson, Stephen T. Chai, Vittorio R. Castelli, Gerald A. Domoto
  • Patent number: 5053826
    Abstract: A method and apparatus for synchronizing a transfer loop in a recirculating color printer includes two spaced pairs of pulleys having a conveyor belt positioned thereabout for conveying sheets to a transfer zone for image transfer and an external pair of idler pulleys. A gripper bar on the conveyor belt advances the sheet. A photoconductive drum includes a portion in the transfer zone. A corona generating device is located in the transfer zone to charge the sheet so that it will attract an image from the photoconductive drum. A motion control servo provides ground-referenced control of motion of the conveyor belt as the gripper bar is delivered to the transfer zone. In the transfer zone, control is shifted to a phase detector which maintains constant the initially sensed phase between idler pulleys and a photoconductive drum coaxial therewith.
    Type: Grant
    Filed: December 21, 1990
    Date of Patent: October 1, 1991
    Assignee: Xerox Corporation
    Inventors: Vittorio R. Castelli, Stephen T. Chai
  • Patent number: 4394667
    Abstract: An optical disk recorder in which the optical disk, the drive spindle and the disk drive motor are moved or pivoted in an arcuate path relative to stationary laser optics. When moved in such an arcuate path, the optical disk, spindle and drive motor have a lessened movement of inertia (compared to linear movement thereof) which permits relatively fast accessing of an optical disk without a large drive motor. The accessing system can be naturally statically balanced by placing the spindle and the drive motor or opposite sides of the pivot point.
    Type: Grant
    Filed: March 26, 1982
    Date of Patent: July 19, 1983
    Assignee: Xerox Corporation
    Inventors: David Cheng, Stephen T. Chai
  • Patent number: 4215932
    Abstract: An apparatus and method of use in which a first photoconductive belt arranged to move about an endless operative path in an electrophotographic printing machine is replaced by a second photoconductive belt. The leading marginal region of the second photoconductive belt is secured to the first photoconductive belt. As the first photoconductive belt moves about the operative path, it positions the second photoconductive belt thereabout. After the second photoconductive belt is positioned about the operative path, the first photoconductive belt is removed therefrom and separated from the second photoconductive belt. The leading marginal region of the second photoconductive belt is then secured to the trailing marginal region thereof.
    Type: Grant
    Filed: June 29, 1979
    Date of Patent: August 5, 1980
    Assignee: Xerox Corporation
    Inventors: Vittorio Castelli, Ralph A. Hamaker, Stephen T. Chai
  • Patent number: 4001892
    Abstract: An apparatus for removing contaminant particles from an enclosure containing a rotating magnetic disk by using the air flow created by rotation of the disk. A tacky substance is provided at a point of maximum centrifugal force within the enclosure so that contaminant particles are permanently captured. Means can be provided for refreshing the tacky substance.
    Type: Grant
    Filed: March 17, 1975
    Date of Patent: January 4, 1977
    Assignee: Xerox Corporation
    Inventors: Vittorio Castelli, Stephen T. Chai