Patents by Inventor Joseph H. Robinson

Joseph H. Robinson 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).

  • Valve stem construction
    Patent number: 4916789
    Abstract: A valve stem formed by evaporative pattern (or lost foam) casting a hollow or solid rod member inside of the elongated outer member. Since the stem is thereby cast to near net shape, little machining is required to finish it. The elongated member can have on its outer surface coarse square threads, a thrust ring, a flattened transition and a retaining nut threaded end. The rod member can advantageously be made of a material that is stronger and less expensive than that of the copper base alloy of the elongated member.
    Type: Grant
    Filed: April 13, 1989
    Date of Patent: April 17, 1990
    Assignee: Robinson Foundry, Inc.
    Inventor: Joseph H. Robinson