Patents by Inventor Chan K. Shiu

Chan K. Shiu 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).

  • Flow cut-off device for insertion in a gas duct
    Patent number: 4257448
    Abstract: The device has a gas passage of adjustable flow cross-section through which gas flows in normal use. Inflowing gas also acts on a blocking member, and when the pressure of the inflow gas rises above a certain value, the pressure on the blocking member is sufficient to move the blocking member into the gas passage to block the passage. The blocking member is then retained in position in the passage, blocking the gas flow by the gas pressure. The blocking member can be a ball which is moved against the force of gravity by the pressure of the gas to close the passage.
    Type: Grant
    Filed: December 15, 1978
    Date of Patent: March 24, 1981
    Inventors: Chan K. Shiu, Leung W. Kwong