Patents by Inventor Tsorng J. Maa

Tsorng J. Maa 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).

  • Gate valve
    Patent number: 4771805
    Abstract: A gate valve having a metal-to-metal seal between the gate (26) and the seat carrier (20) and a metal-to-metal seal between the seat carrier (20) and the valve body (10) with the seat carrier and valve body having complementary spaced frustoconical surfaces (18,22).
    Type: Grant
    Filed: November 16, 1983
    Date of Patent: September 20, 1988
    Assignee: Vetco Gray Inc.
    Inventor: Tsorng J. Maa