Patents by Inventor De Fu Chen

De Fu Chen 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: 6808159
    Abstract: A nonrefillable valve is provided that allows for an initial filling of a container, but prevents subsequent refilling of the container. The valve operating assembly includes a valve stem and a valve core which is slidably received in the distal end of the valve stem. In a first position, the valve core resides above a rim or protrusion within the chamber. After filling of the container, a second position is defined when the valve stem is operated to force the valve core beyond the protrusion and in seating engagement with a valve seat, thus sealing the container. The valve is then selectively operated in a third or open position to discharge the container as desired. Subsequent refilling of the container is prevented by the force of fluid reentering the valve which forces the valve core to its seated engagement with the valve seat.
    Type: Grant
    Filed: July 16, 2003
    Date of Patent: October 26, 2004
    Assignee: Discount Refrigerants, Inc.
    Inventor: De Fu Chen
  • Patent number: 6595486
    Abstract: A nonrefillable valve is provided that allows for an initial filling of a container, but prevents subsequent refilling of the container. The valve operating assembly includes a valve stem and a valve core which is slidably received in the distal end of the valve stem. In a first position, the valve core resides above a rim or protrusion within the chamber. After filling of the container, a second position is defined when the valve stem is operated to force the valve core beyond the protrusion and in seating engagement with a valve seat, thus sealing the container. The valve is then selectively operated in a third or open position to discharge the container as desired. Subsequent refilling of the container is prevented by the force of fluid reentering the valve which forces the valve core to its seated engagement with the valve seat.
    Type: Grant
    Filed: September 6, 2001
    Date of Patent: July 22, 2003
    Assignee: Discount Refrigerants, Inc.
    Inventor: De Fu Chen
  • Publication number: 20030042447
    Abstract: A nonrefillable valve is especially adapted for an initial charge or fill of a pressurized container, and selective discharge of the container, but prevents subsequent refill of the container. The valve is characterized by a valve body which receives a valve operating assembly. The valve operating assembly includes a valve stem which is raised or lowered within the chamber of the valve, and a valve core which is slidably received in the distal end of the valve stem. In a first or pre-position, the valve core resides above a rim or protrusion within the chamber. After filling of the container, the valve stem is operated to force the valve core beyond the protrusion, and in seating engagement with a valve seat thus sealing the container. A second or closed position of the valve is defined when the valve stem forces the valve core against the valve seat. The valve is then selectively operated in a third or open position to discharge the container as desired.
    Type: Application
    Filed: September 6, 2001
    Publication date: March 6, 2003
    Inventor: De Fu Chen