Patents by Inventor Dong D. Nguyen

Dong D. Nguyen 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).

  • Method and apparatus for detecting amplitude and frequency of web flutter using infrared optical sensor
    Patent number: 5073714
    Abstract: Web flutter in a papermaking machine is monitored by a device which illuminates a portion of the web with infrared light and uses an infrared sensor to monitor the resulting infrared light scattered back from the web. Preferably two infrared light transmitters are used which are angled from each other to insure that light is scattered to the sensor independently of the orientation of the web.
    Type: Grant
    Filed: May 22, 1990
    Date of Patent: December 17, 1991
    Assignee: Union Camp Corporation
    Inventor: Dong D. Nguyen
  • Flutter suppression air foils
    Patent number: 5022166
    Abstract: Apparatus and methods for reducing the amplitude and frequency of web-edge flutter associated with drawing web materials are provided. The apparatus includes a pair of air foils disposed proximate to a pair of opposing planar surfaces of the web. Each of the air foils includes a first convex surface facing the web and disposed in contact with air flowing on the web for producing a venturi effect which reduces at least the flutter amplitude in the open draw.
    Type: Grant
    Filed: June 7, 1990
    Date of Patent: June 11, 1991
    Assignee: Union Camp Corporation
    Inventors: Dong D. Nguyen, Marvin L. Harris
  • Method for determining amplitude and frequency of web flutter
    Patent number: 4992142
    Abstract: An apparatus and method for determining the frequency and amplitude of flutter of a moving web in a web manufacturing operation, is shown to include a sensor for sensing the pressure of air in a region proximate the web and for generating a pressure signal reflective of the air pressure and a signal processor, connected to receive the pressure signal, for determining the amplitudes and frequencies of the flutter from the pressure signal and for generating an indication signal representative of the flutter amplitude and frequency.
    Type: Grant
    Filed: April 2, 1990
    Date of Patent: February 12, 1991
    Assignee: Union Camp Corporation
    Inventor: Dong D. Nguyen
  • Apparatus for determining amplitude and frequency of web flutter
    Patent number: 4968386
    Abstract: An apparatus and method for determining the frequency and amplitude of flutter of a moving web in a web manufacturing operation, is shown to include a sensor for sensing the pressure of air in a region proximate the web and for generating a pressure signal reflective of the air pressure and a signal processor, connected to receive the pressure signal, for determining the amplitudes and frequencies of the flutter from the pressure signal and for generating an indication signal representative of the flutter amplitude and frequency.
    Type: Grant
    Filed: May 10, 1988
    Date of Patent: November 6, 1990
    Assignee: Union Camp Corporation
    Inventor: Dong D. Nguyen