Patents by Inventor Patrick C. P. Cheung

Patrick C. P. Cheung 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: 6032923
    Abstract: A cantilever valve useful for paper handling applications is disclosed. The valve can be batch fabricated in two dimensional valve arrays, with each valve in the array being controlled by passive matrix addressing. Typically, each valve includes a valve housing having an aperture plate defining an aperture therethrough, and an opposing port plate positioned in spaced apart relationship to the aperture plate. A flexible film or strip is attached at its first end between the aperture and port plates and is unattached so that it is free to move between the aperture and port plates at its second end. Valve action is provided by use of a single switching electrode for moving the flexible film between an aperture blocking position and an aperture open position, with the switching electrodes positioned adjacent to the port plate.
    Type: Grant
    Filed: January 8, 1998
    Date of Patent: March 7, 2000
    Assignee: Xerox Corporation
    Inventors: David K. Biegelsen, Warren B. Jackson, Patrick C. P. Cheung
  • Patent number: 6004395
    Abstract: A valve array for supporting objects such as paper with controlled fluid flow is disclosed. Optional valve arrays can be used to controllably eject marking agents for marking or coating a paper or other suitable substrate. Each valve in the valve array has one or more flap elements positioned in a valve chamber. These flap elements are movable to alternatively block the fluid flow through valve chamber outlets with the aid of various catch mechanisms for controllably latching the flap elements. The catch mechanisms have a disabled state and an activated state for holding and allowing release of the flap elements. Once the catch mechanism are disabled, the flap elements are free to move to another position, provided they can overcome the mechanical fluid flow forces that tend to hold it in position. To counter and utilize such forces for moving the flap elements, an impulse mechanism kicks the flap element into the valve chamber, away from the catch mechanisms.
    Type: Grant
    Filed: December 19, 1997
    Date of Patent: December 21, 1999
    Assignee: Xerox Coporation
    Inventors: Mark H. Yim, Warren B. Jackson, James G. Chase, David K. Biegelsen, Patrick C. P. Cheung, Andrew A. Berlin, Kenneth N. Horne
  • Patent number: 5971355
    Abstract: A valve array system including microelectromechanical valves embedded in a dielectric substrate is disclosed. These microelectromechanical valves can be batch fabricated using resin impregnated dielectric laminates having photolithographically formed circuitry for electrical connections. Movable components of valves, including electromagnetic or electrostatically actuated membranes, flaps, or beams, can be formed from laminate material using sacrifice layers and etching.
    Type: Grant
    Filed: November 27, 1996
    Date of Patent: October 26, 1999
    Assignee: Xerox Corporation
    Inventors: David K. Biegelsen, Warren B. Jackson, Patrick C. P. Cheung, Mark H. Yim, Andrew A. Berlin
  • Patent number: 5941501
    Abstract: A bistable valve useful for paper handling applications is disclosed. The valve can be batch fabricated in two dimensional valve arrays, with each valve in the array being controlled by passive matrix addressing. Typically, each valve includes a valve housing an electrically conductive movable element such as cantilever beam, diaphragm or film. Valve action is provided by use of housing embedded switching electrodes for moving the movable element between an aperture blocking position and an aperture open position. To reduce unswitched movement when the switching electrode bias is reduced or not present, electrostatic or mechanical catches can be used.
    Type: Grant
    Filed: September 6, 1996
    Date of Patent: August 24, 1999
    Assignee: Xerox Corporation
    Inventors: David K. Biegelsen, Patrick C. P. Cheung, Andrew A. Berlin, Warren B. Jackson, Lars-Erik Swartz, Raj B. Apte, Richard H. Bruce
  • Patent number: 5897097
    Abstract: A bistable valve useful for paper handling applications is disclosed. The valve can be batch fabricated in two dimensional valve arrays, with each valve in the array being controlled by passive matrix addressing. Typically, each valve includes a valve housing having an aperture plate defining an aperture therethrough, and an opposing plate positioned in spaced apart relationship to the aperture plate. A flexible film or strip is attached at its first end to the aperture plate and at its second end to the opposing plate. Valve action is provided by use of at least two switching electrodes for moving the flexible film between an aperture blocking position and an aperture open position, with at least one of the switching electrodes positioned adjacent to the aperture plate and at least one of the switching electrodes positioned adjacent to the opposing plate. To reduce unswitched movement when the switching electrode bias is reduced or not present, at least two electrostatic or mechanical catches are used.
    Type: Grant
    Filed: September 6, 1996
    Date of Patent: April 27, 1999
    Assignee: Xerox Corporation
    Inventors: David K. Biegelsen, Patrick C. P. Cheung, Andrew A. Berlin, Warren B. Jackson, Lars-Erik Swartz, Raj B. Apte, Richard H. Bruce
  • Patent number: 5839722
    Abstract: A paper handling system for air mediated transport of sheets or pages of paper is disclosed. Microelectromechanical valves and sensors are embedded in a dielectric substrate for tracking and controlling paper transport. These microelectromechanical systems can be batch fabricated using resin impregnated dielectric laminates having photolithographically formed circuitry for electrical connections. Use of high speed sensor and valve control systems permit dynamic adjustments to paper trajectory during paper transport.
    Type: Grant
    Filed: November 26, 1996
    Date of Patent: November 24, 1998
    Assignee: Xerox Corporation
    Inventors: Andrew A. Berlin, Patrick C. P. Cheung, David K. Biegelsen, Warren B. Jackson, Mark H. Yim