Patents by Inventor Arthur S. Hedberg

Arthur S. Hedberg 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: 4241492
    Abstract: The present invention concerns a method of manufacture of valve seats which comprises forming a series of vertically stacked molds each having at least one mold cavity with a configuration approximating that of a ring-shaped valve seat insert blank. After the molds are formed, they are stacked and the cavities are connected by a common molten metal passageway in such a way that the passageway connects with an axially facing outer surface of each mold cavity to provide a lap gating relationship. Molten metal is then poured into the lap gated passageway to form a series of valve seat insert blanks each having a gate formed on an axially outer face. The blanks are then removed from the molds. Various grinding operations are then applied to the blanks and the axially outer-facing surfaces of the blanks are ground to remove the gates to form valve seats for use in internal combustion engines.
    Type: Grant
    Filed: December 21, 1978
    Date of Patent: December 30, 1980
    Assignee: Wells Manufacturing Company
    Inventor: Arthur S. Hedberg